Surgical Neurology

2009-12-01

In this issue…

James I. Ausman — 2009-12-01

Don't let the phrase “Fuzzy Logic” discourage you from reading the article by Shamin et al from Pakistan and Qatar on the subject. The concept makes common sense. Here is the story: we have all grown up and learned a statistical system, the Aristotelian system, in which the world is black or white; the event either happened or it did not happen. Either a patient has cancer or he or she does not; either they have diabetes or they do not. In this system there is no room for mild diabetes. Either you have it or you don't. On that basis the statistics are calculated. That is Aristotelian logic. But the world we live in is not black or white, it is gray. You can have a limited form of cancer or mild diabetes. A grading system can be applied to the degree of presence of such diseases to make statistical calculations. This is “Fuzzy Logic.” It is used in most branches of science except medicine. The authors apply Fuzzy Logic to predict those who will have a good or poor result from surgery of the lumbar disk. They found a highly predictive relationship using Fuzzy Logic among some of the variables they chose to predict outcome and the final result. This is a terrific article. We wrote about Fuzzy Logic in this journal 8 years ago. Fuzzy Logic will become common in medical practice because it makes sense. Randomized studies will also disappear because the data of the future will be based on each individual's parameters from his or her imaging and biology. Read the Discussion first. The Abstract is too confusing to read first. Then, read the article for more information.

A note of respect

James I. Ausman — 2009-12-01

Surgical Neurology was founded by Dr Paul Bucy in 1973. Dr Bucy was the long-time Editor of the Journal of Neurosurgery and, after some differences with the AANS, sought to begin an independent journal. Dr Bucy was a stout man who had a booming voice and was an eloquent speaker. He was worldly and played an important role in the development of the World Federation of Neurosurgical Societies. He was very controversial because he was innovative, creative, and an independent thinker. His peers were people who have made a huge impact on neurology and neurosurgery—Percival Bailey and A. Earl Walker, among others. He was well-read and was part of a regular “salon,” or meeting of educated people from all disciplines outside of medicine, so he was broadly educated. He broke with tradition in writing Editorials in Surgical Neurology that discussed controversial topics. He exhorted neurosurgeons to think of new ideas and questioned the practices that were widely adopted but that did not make sense. He was not elected to any leadership position in neurosurgery, most likely because he was willing to say what he believed and not be a part of the “neuropolitical” game. To me he was an inspiring person who affected my life particularly as Editor of the journal he founded. He was Editor of Surgical Neurology from 1973 to 1985.

A note of appreciation to the editorial board

James I. Ausman — 2009-12-01

Editing a medical journal is not a one-person job. Without the advice of many wise people with good judgment offering constructive suggestions about the direction of the journal and other matters, the Editor cannot select the right papers. I was privileged to have an outstanding Editorial Board. These people, from all over the world, were picked because of their good judgment. I am especially appreciative of the help of Associate Editors Ezio Di Rocco (Italy), Nancy Epstein (USA), Bernard George (France), Bob Goodkin (USA), Jens Hasse (Denmark), Juha Hernesniemi (Finland), Yucel Kanpolat (Turkey), Ming-Chien Kao (Taiwan), Namio Kodama (Japan), Ben Roitberg (USA), Julio Sotelo (Mexico), Atos de Sousa (Brazil), and Jizong Zhao (China), who I called on frequently for advice and opinions about scientific papers. Each of them are individually outstanding and highly accomplished in their own fields.

A note of gratitude to the readers of Surgical Neurology

James I. Ausman — 2009-12-01

As people have learned that Surgical Neurology as a journal will end, I have received many notes and comments from our readers about how much the journal has meant to them. I am overwhelmed by these comments and most appreciative.

Power: how to get it and how to use it for the future

James I. Ausman — 2009-12-01

Neurosurgeons represent 1% or less of all physicians; thus, as a group, the specialty has little power. In the 21st century, we will see a continuation of power becoming localized in large groups. Multinational corporations will have power as they will control large segments of their markets. It is for this reason that businesses merged in the 20th century and it is the reason this trend will continue in the 21st century. Governments will also become more powerful as can be seen in the trend in the United States toward socialism.

Technology or judgment?

James I. Ausman — 2009-12-01

I remember a meeting in Columbia I attended some years ago when speakers presented their talks to the audience. Each speaker talked about the fantastic operations they were doing and the technology they were using. The neurosurgeons in the audience, who could not afford this technology, were made to feel inferior and inadequate. I was so angry that I tore up my planned lecture and compared the behavior of the visiting speakers to a rich person who opens his home for 1 day to the poor people in the surrounding area inviting them to see his luxurious home and eat foods they could never have. Then, they were sent home to live their daily lives. To me this behavior shows a total lack of understanding of the needs of the people and the community.

Fuzzy Logic in neurosurgery: predicting poor outcomes after lumbar disk surgery in 501 consecutive patients

Muhammad Shahzad Shamim, Syed Ather Enam, Uvais Qidwai — 2009-12-01

Abstract: Background: Despite a lot of research into patient selection, a significant number of patients fail to benefit from surgery for symptomatic lumbar disk herniation. We have used Fuzzy Logic-based fuzzy inference system (FIS) for identifying patients unlikely to improve after disk surgery and explored FIS as a tool for surgical outcome prediction.Methods: Data of 501 patients were retrospectively reviewed for 54 independent variables. Sixteen variables were short-listed based on heuristics and were further classified into memberships with degrees of membership within each. A set of 11 rules was formed, and the rule base used individual membership degrees and their values mapped from the membership functions to perform Boolean Logical inference for a particular set of inputs. For each rule, a decision bar was generated that, when combined with the other rules in a similar way, constituted a decision surface. The FIS decisions were then based on calculating the centroid for the resulting decision surfaces and thresholding of actual centroid values. The results of FIS were then compared with eventual postoperative patient outcomes based on clinical follow-ups at 6 months to evaluate FIS as a predictor of poor outcome.Results: Fuzzy inference system has a sensitivity of 88% and specificity of 86% in the prediction of patients most likely to have poor outcome after lumbosacral miscrodiskectomy. The test thus has a positive predictive value of 0.36 and a negative predictive value of 0.98.Conclusion: Fuzzy inference system is a sensitive method of predicting patients who will fail to improve with surgical intervention.

Commentary

Phillip Dickey — 2009-12-01

The authors have presented an interesting clinical application of Fuzzy Logic to the problem of selecting patients for lumbar diskectomy. Although the method cannot substitute for clinical judgment, it certainly can be used as a tool for teaching residents and junior surgeons how to select patients. The use of Fuzzy Logic in other clinical problems has been well discussed by the authors, and they present a good simplification of the mathematics that most clinicians likely can appreciate.

Neuromodulation of the superior hypogastric plexus: a new option to treat bladder atonia secondary to radical pelvic surgery?

Marc Possover, Vito Chiantera — 2009-12-01

Abstract: Background: The aim of this study is to report on the impact of neuromodulation to the superior hypogastric plexus in patients with bladder atonia secondary to pelvic surgery.Methods: In 4 consecutive patients with bladder atonia secondary to pelvic surgery, we performed a laparoscopic implantation of a neurostimulator—LION procedure—to the entire superior hypogastric plexus.Results: Of the 4 reported patients, 3 are able to partially void or empty their bladder.Conclusions: If the presented results could be obtained in further patients and maintained in long-term follow-up, the LION procedure to the superior hypogastric plexus could change the management of bladder function in patients with bladder atonia.

Preparing the ethical future of deep brain stimulation

Emily Bell, Ghislaine Mathieu, Eric Racine — 2009-07-16

Abstract: Background: Deep brain stimulation is an approved and effective neurosurgical intervention for motor disorders such as PD and ET. Deep brain stimulation may also be effective in treating a number of psychiatric disorders, including treatment refractory depression and OCD. Although DBS is a widely accepted therapy in motor disorders, it remains an invasive and expensive procedure. The ethical and social challenges of DBS need further examination, and discussion and emerging applications of DBS in psychiatry may also complicate the ethical landscape of DBS.Methods: To identify and characterize current and emerging issues in the use of DBS, we reviewed the neurosurgical literature on DBS as well as the interdisciplinary medical ethics and relevant psychological and sociological literatures. We also consulted the USPTO database, FDA regulations and report decisions, and the business reports of key DBS manufacturers.Results: Important ethical and social challenges exist in the current and extending practice of DBS, notably in patient selection, informed consent, resource allocation, and in public understanding. These challenges are likely to be amplified if emerging uses of DBS in psychiatry are approved.Conclusions: Our review of ethical and social issues related to DBS highlights that several significant challenges, although not insurmountable, need much closer attention. A combination of approaches previously used in neuroethics, such as expert consensus workshops to establish ethical guidelines and public engagement to improve public understanding, may be fruitful to explore.

Commentary

Konstantin V. Slavin — 2009-07-16

Widespread acceptance of deep brain stimulation and constant introduction of new indications for this fascinating procedure bring up some rather unexpected challenges that have to do with a variety of social, economic, legal, and medical issues. In addition to approved use in tremor and PD, DBS today is used for dystonia and Tourette syndrome, cluster headaches and aggressive behavior, major depression, and obsessive-compulsive disorder. Other conditions such as obesity, anorexia, minimally conscious state, and Alzheimer disease are becoming subjects of clinical investigations.

Psychiatric symptom changes after corticoamygdalohippocampectomy in patients with medial temporal lobe epilepsy through Symptom Checklist 90 Revised

2009-07-16

Abstract: Background: Corticoamygdalohippocampectomy (anterior temporal lobe resection plus amygdalohippocampectomy) is common in epilepsy surgery. Pre- and postoperative psychiatric disorders occurred sometimes in patients with refractory medial TLE. We want to know if CAH has an affirmative effect on the psychiatric symptom of patients with medial TLE through a quantitative method.Methods: Sixty-two patients with medial TLE who had CAH accomplished SCL-90-R questionnaires thrice (presurgical and postsurgical 1 and 2 years). Average GSI scores in SCL-90-R were calculated and statistically analyzed.Results: There was no statistical difference in the presurgical average GSI scores between Engel I and Engel II to IV subgroup. Postoperative 1 and 2 years' average GSI scores of Engel II to IV subgroup were both statistically higher than those of Engel I subgroup. There were no statistical differences between other subgroups in different time. Postsurgical 1 and 2 years' average GSI scores of the whole group and Engel I subgroup were statistically lower than those of presurgery. Postoperative 2 years' average GSI scores of the whole group and Engel I subgroup were statistically lower than those of postsurgical 1 year. For Engel II to IV subgroup, there were no statistical differences among the average GSI scores in different time.Conclusion: Corticoamygdalohippocampectomy could improve the psychiatric symptoms of patients with TLE as assessed by the SCL-90-R. This improvement was related to the therapeutic effect and was not related to sex, lateralization, and MRI abnormality.

Commentary

Gary W. Mathern — 2009-07-16

Guangming et al present a study where they administered the SCL-90-R to patients with TLE undergoing CAH. The SCL-90-R was filled out presurgery and 1 and 2 years post-CAH. The authors found that there were improved scores only for patients who were seizure free (Engel class I) 1 and 2 years after surgery. Patients who were Engel II to IV were not improved, nor were there differences pre- and post-CAH based on sex, side removed, or presence of MRI lesion.

Comparison of postoperative cognitive function in patients undergoing surgery for ruptured and unruptured intracranial aneurysm

2009-12-01

Abstract: Background: Patients with SAH often experience cognitive decline. Previous studies used normal volunteers, published normal test values, and orthopedic patients as controls to identify factors for postoperative cognitive decline. The present study excluded the effects of surgery by comparing cognitive function after surgical repair in patients with aneurysmal SAH and patients with unruptured intracranial aneurysm.Methods: This study recruited 117 patients with SAH due to ruptured aneurysm and 39 patients with incidentally found unruptured intracranial aneurysms. The cognitive test battery consisted of the Japanese translation of the WAIS-R, the Japanese translation of the WMS, and the recall trial of the ROCF. Postoperative neuropsychological test scores for the patients with SAH and control subjects were compared using group-rate and event-rate analysis. The relationship between clinical variable and postoperative cognitive decline in the patients with SAH was evaluated by univariate analysis using the Mann-Whitney U test or χ2 test.Results: Group-rate analysis showed that the WAIS-R and ROCF scores were significantly lower in the SAH group than in the control group. Event-rate analysis demonstrated that the incidence of cognitive decline in the patients with SAH (73 [62.4%] of the 117 patients) was significantly higher than that in the control subjects (12 [30.8%] of 39 patients). The Hunt and Hess grade was significantly higher in patients with postoperative cognitive decline.Conclusion: The cognitive function after SAH was significantly correlated with Hunt and Hess grade on admission when using patients with postoperative unruptured intracranial aneurysm as the control group.

Commentary

Moises Gaviria — 2009-12-01

This article compares postoperative cognitive functions of patients undergoing surgery for ruptured and unruptured intracranial aneurysms; the study included 117 patients with SAH due to ruptured aneurysm and 39 patients with incidentally found unruptured intracranial aneurysms. Cognitive functions after SAH were significantly correlated with Hunt and Hess grade on admission when using patients with postoperative unruptured intracranial aneurysms as the control group.

The combined approach to intracranial aneurysm treatment

Brian L. Alexander, Howard A. Riina — 2009-10-12

Abstract: Background: A consecutive series of patients with intracranial aneurysms in the practice of one neurovascular surgeon was retrospectively reviewed to illustrate that one physician can become proficient in microneurosurgery as well as endovascular surgery and achieve favorable outcomes in both disciplines. This supports one model of training for cerebrovascular surgeons that includes the complimentary practice of open microneurovascular surgery with endovascular surgery.Methods: The senior author (HAR) treated 351 patients with 413 aneurysms between July 2001 and March 2007. Of these, 172 patients (216 aneurysms) were treated with open microneurosurgical techniques and 179 patients (197 aneurysms) were treated using endovascular techniques.Results: Complete obliteration was attained in 94.3% of clipped aneurysms, and 61.9% and 65.9% of coiled aneurysms immediately and after at least 6 months of follow-up, respectively. At latest evaluation, 93% of endovascular patients and 90% of microneurosurgical patients had good clinical outcomes (GOS, 4 or 5; mean follow-up, 23 months; combines ruptured and unruptured cohorts). Procedure-related mortality included 1 surgical patient and 2 endovascular patients.Conclusions: Because the fields of microvascular and endovascular surgeries are both technically complex, there has been concern that hybrid cerebrovascular surgeons cannot perform each technique with the skill necessary to achieve good outcomes. When compared to clipping and coiling reviews in the neurosurgical literature, we illustrate that one hybrid neurovascular surgeon is capable of attaining great facility in both techniques and that this type of physician will represent one practice model of cerebrovascular specialist in the future. This has potential implications for the training of hybrid cerebrovascular surgeons.

Commentary

Elad I. Levy, L. Nelson Hopkins — 2009-10-12

The article by Alexander and Riina highlights the important reality that the management of aneurysms requires multiple tools. Coiling and clipping of aneurysms are 2 distinct strategies that are complementary, not adversarial. Only with proper understanding of the limitations and effectiveness of each treatment modality can clinicians hope to achieve optimal outcomes while minimizing morbidity risk.

Intracranial angioplasty with Gateway-Wingspan system for symptomatic atherosclerotic stenosis: preliminary results of 27 Chinese patients

Zhen-Wei Zhao, Jian-Ping Deng, Shi-Ming He, Huai-Zhou Qin, Li Gao, Guo-Dong Gao — 2009-12-01

Abstract: Background: We investigated the safety of treatment of symptomatic intracranial atherosclerotic stenoses with the Gateway-Wingspan system and its initial effect on prevention of ischemic events.Methods: Twenty-seven cases of symptomatic intracranial atherosclerotic stenoses were treated with angioplasty with a Wingspan stent. Location of stenoses, extent of stenoses before and after angioplasty, success rate of treatment, occurrence of procedural complications, and changes in recurrence of symptoms of ischemic events 30 days after treatment were recorded.Results: Twenty-nine angioplasties with the Wingspan system were successfully carried out in 29 stenoses in 27 patients. Of 29 stenoses, 17 were in the posterior circulation, and 12, in the anterior circulation. The degree of stenoses was reduced from baseline 71.8% (56%-87.8%) to 24.9% (0%-45%) after stenting. Complications were seen in four patients (14.8%), 3 of which were lesion-related infarction of a perforated artery, and 1 was a non-lesion-related infarction. Two complications led to transient neurologic dysfunction, one led to defect of the visual field, and one led to hemiplegia. The prevalence of morbidity and serious morbidity were 7.4% and 3.7%, respectively, and no death occurred. No new ischemic events happened during 30 days after stenting.Conclusion: Angioplasty with the Wingspan system to treat symptomatic intracranial atherosclerotic stenoses appears to be safe. Its initial effect on prevention of ischemic events is acceptable.

Commentary

Y. Pierre Gobin — 2009-12-01

This is an interesting series from a large Chinese center confirming the safety and short-term efficacy of intracranial stenting with the Wingspan system. This article does not report on long-term follow-up of stented patients, although this is a potential problem because of the high rate of restenosis observed with bare stents. The ongoing Sammpris trial—which is randomizing patients with severe symptomatic intracranial stenosis to stenting versus medical management—will answer many of the questions we have about the long-term benefit of intracranial stenting.

Single-center experience with the Neuroform stent for endovascular treatment of wide-necked intracranial aneurysms

2009-07-15

Abstract: Background: Stent-assisted coiling is an accepted endovascular treatment (EVT) for wide-necked intracranial aneurysms. The Neuroform stent (Target Therapeutics, Fremont, Calif) is a flexible nitinol self-expandable stent that was designed to potentially overcome the limitations of balloon expandable coronary stents in the intracranial circulation. The aim of this study was to reenforce the use of this stent for EVT of wide-necked cerebral aneurysms.Methods: Between March 2005 and March 2008, 24 patients harboring wide-necked cerebral aneurysms were treated with stent reconstruction of the aneurysm neck. Inclusion criteria restricted the group to adult patients with wide-necked intracranial aneurysms (ruptured and unruptured lesions). Immediate postprocedure angiography studies were performed to determine successful coil occlusion of the aneurysm as well as patency of the parent vessel. We assessed the clinical history, aneurysm dimensions, and technical detail of the procedures, including any difficulties with stent placement and deployment, degree of aneurysm occlusion, and complications. Clinical outcome was assessed with the Glasgow Outcome Scale (GOS).Results: The stent was easily navigated and precisely positioned in 24 of 26 cases. However, technical difficulties occurred in 9 patients, including difficulties in crossing the stents interstice in 6 cases, inadvertent stent delivery (n = 1), and incapacity of stent delivery (n = 1) and incapacity of crossing the neck (n = 1). These latter 2 cases were classified as failures of the stent-assisted technique. A single procedural complication occurred, involving transient nonocclusive intrastent thrombus formation, which was treated uneventfully with abciximab. Seventeen patients experienced excellent clinical outcomes (GOS 5), with good outcomes (GOS 4) in 5 patients and a poor outcome (GOS 3) in 2 patients. There were no treatment-related deaths or neurologic complications (mean clinical follow-up, 12 months). Angiographic results consisted of 17 complete occlusions, 4 neck remnants, and 3 incomplete occlusions.Conclusions: The Neuroform stent is very useful for EVT of wide-necked intracranial aneurysms because it is easy to navigate and to deploy accurately. In most cases, the stent can be deployed precisely, even in very tortuous carotid siphons. Although in some cases delivery and deployment was challenging, clinically significant complications were not observed.

A rabbit model for efficacy evaluation of endovascular coil materials

2009-12-01

Abstract: Background: To investigate biomaterials seeking for their possible use for aneurysm treatment, in vivo screening tests using a number of potential materials are required. However, there is no established animal model that is suitable for such purpose. Some models require special preparation of tested materials for transcatheter delivery and others are inappropriate in view of their cost-effectiveness. The purpose of this study is to establish an animal model that overcomes these limitations and help us select potential materials before the preclinical evaluation.Methods: Bilateral CCAs in a rabbit were surgically ligated, and a 2-cm segment of either a bare platinum coil or a polymeric coil (a platinum coil coated with PLGA 10/90) was implanted into each blind-ended arterial segment (n = 26). They were harvested at day 1, 7, 10, 14, or 30, respectively. Angiographic and histologic evaluations as well as quantitative analysis on the development of the organized thrombus were performed.Results: One day after the implantation, both platinum and PLGA coils were surrounded by immature thrombus that was induced by blood flow stagnation in the arterial segment. At day 7, minimal thrombus organization was observed around both types of materials. At postimplantation days 10 and 14, fibrocellular responses, the early findings of the thrombus organization process, were observed in both material groups. Such histologic findings were more prominent in the PLGA coil group as compared to the platinum coil group (day 10, P = .051; day 14, P = .011). Well-organized thrombus was observed in both material groups at day 30 without showing statistical difference (P = .12).Conclusion: Given the cost-effectiveness, the simple material preparation process, and its feasible histologic evaluation methods, this new animal model can be useful in screening other potential biomaterials for the development of new coil devices.

Commentary

Karel G. TerBrugge — 2009-12-01

Research into embolic materials is to be encouraged. So far, the clinical impact of modified coil materials has not been very impressive, and even their need remains controversial. Long-term studies have not shown a proven need for complete obliteration of aneurysm lumen or neck, as subjective and industry thinking would lead us to believe. To create models allowing us to compare objectively the impact of various embolic factors is important and may help to prevent the release of products without proven evidence of their proposed benefits. Of course, the differences in extracranial vs intracranial environments will also have to be addressed.

Do we need a neurosurgical Interpol?

Ibrahim Sbeih — 2009-10-12

Interpol is an international organization of police and law enforcement authorities spanning 140 countries. It was founded in 1923 and works to ensure coordination and cooperation among police departments and its member authorities.

Wound-peritoneal shunts: part of the complex management of anterior dural lacerations in patients with ossification of the posterior longitudinal ligament

Nancy E. Epstein — 2009-08-10

Abstract: Background: The complex management of dural lacerations occurring after the resection of multilevel ossification of the posterior longitudinal ligament (OPLL) requires further clarification.Methods: Both preoperative MR and CT studies documented multilevel ventral cord compression attributed to OPLL with kyphosis in 82 patients requiring multilevel anterior corpectomy/fusion (ACF) (average, 2.6 levels) followed by posterior fusion (PF) (average, 6.6 levels) under the same anesthetic. The 5 patients who developed intraoperative dural lacerations/penetration demonstrated the single-layer sign (2 patients: large central mass) or the double-layer sign (3 patients: hyperdense/hypodense/hyperdense layers) on preoperative 2-dimensional CT studies. All 5 patients were managed with complex dural repair (sheep pericardial grafts, fibrin sealant, microfibrillar collagen) and had shunts placed (wound-peritoneal and lumboperitoneal).Results: After complex dural repair/shunting, all 5 intraoperative dural lacerations (DLs) resolved. The application of low-pressure wound-peritoneal shunts was unique to this study (Uni-Shunts, Codman, Johnson and Johnson, Dorchester, Mass). The proximal end is placed lateral/parallel to the fibula strut graft/plate complex, whereas the distal catheter is tunneled into the peritoneum in the right upper quadrant (always prepared and draped in anticipation of the need for a shunt).Conclusions: Of 82 patients undergoing multilevel anterior corpectomy for OPLL/kyphosis, 5 developed intraoperative DLs successfully managed with a complex dural repair, wound-peritoneal, and lumboperitoneal shunting procedures.

Commentary

Howard Morgan — 2009-08-10

Dr Epstein presents a logical method for dealing with a complicated neurosurgical problem—that of the impossibility of maintaining the integrity of the dura after resection of OPLL in certain patients with cervical myelopathy and kyphosis. Shunting the CSF into the abdominal cavity maintains a closed system and has obvious advantages over multiple percutaneous aspirations or temporary lumbar external drainage, that is, the risks of infection and repeated draining should be substantially lower with an indwelling shunt. These patients are usually older and have significant comorbidities, making their surgical care more complicated and their risks relatively high, as Dr Epstein notes. The use of posterior instrumentation and fusion to buttress the anterior construct is well-reasoned and illustrated, although some surgeons likely would have used lateral mass/pedicle screws and rods instead of rods, eyelets, and cables.

Commentary

Hiroshi Nakagawa — 2009-08-10

Anterior corpectomy with direct removal of prominent OPLL and fixation is one of the most difficult and challenging procedures in cervical spine surgery. Wound-peritoneal shunt with LP shunt reported by the author is one way to deal with dural tear with CSF leakage, which is one of the annoying complications of this procedure. In my personal series of 185 cases of cervical OPLL for the last decade, only 4 cases (2.1%) needed a combined approach—which consisted of multilevel corpectomy for removal of prominent OPLL and fixation after expansive laminoplasty because of neurologic deterioration in follow-ups. Therefore, expansive laminoplasty, either open-door or double-door, is an effective and less invasive procedure with a few complications for extensive OPLL of continuous or mixed type. However, the choice of the procedure may be affected by the surgeon's experience, philosophy, and the differences in medical and socioeconomic systems in each country and region.

Attempting homicide by inserting sewing needle into the brain: Report of 6 cases and review of literature

Abbas Amirjamshidi, Arman Rakan Ghasvini, Maysam Alimohammadi, Kazem Abbassioun — 2009-08-10

Abstract: Background and objectives: Child abuse with sewing needle is a rare but well-known homicide attempt threatening the life of victims. Information about diagnosis and treatment of such cases either in the acute or chronic phases is lacking and ambiguous in the literature. This study intends to report the experience of 6 victims of homicide attempt who presented to the authors in different decades of life and were managed in different ways. This may deliver some evidences to the literature regarding management of further cases encountered by neurosurgeons.Material and methods: The authors had the chance of managing 6 patients referred to their trauma center harboring one or more sewing needles within their cranium. There were 3 male and 3 female patients, with 2 patients in their first decade of life, and the others, each in either decade of life. The youngest was 6, and the eldest 51 year old. The elder patients were having vague headaches, for which a plain skull x-ray or CT of the brain lead to the diagnosis of persisting intracranial foreign bodies. Chronic headache was the main complaint of the patients. Four patients underwent surgical removal of the sewing needle, and 2 are being followed.Results: Among the 4 patients who underwent surgery, 1 died after a short period of ‘akinetic mutism.’ Headache and limb paresthesia improved 6 months after the operation in 2 cases, and the other 1 remained unchanged. The cases under observation have been doing well. Biochemical analysis of the rusted needle showed a composite of oxidant form of some of the elements of needle such as Fe, Mn, and Cr.Conclusion: In spite of standard algorithms proposed for management of penetrating head wounds, selection of the best treatment in the victims harboring sewing needles in their brain needs close cooperation between neurosurgeons, pediatricians, psychiatrists, and social workers. Furthermore, there is no absolute indication for removing sewing intracranial needles detected in the later decades of life.

Commentary

Jorge Lazareff — 2009-08-10

Many clinical pearls can be drawn from Professor Amirjamshidi article; the interested reader will discern them according to his or her practice and experience. I personally profited from what I found under: “there may be a question about how the brain deals with such foreign bodies?”.

What will you do with the rest of your life?

James I. Ausman — 2009-12-01

By the year 2030, 20% of the United States (US) population (representing 71 million people) will be older than 65 years. Similarly, in China, Japan, and Europe, aging populations will begin to overwhelm societies, placing more burden on the younger for their support. There is a prevailing philosophy that all people should become retired in Japan at 60 years of age and in the US at 65 to 70 years. Yet when these ideas occurred, first developed by Bismarck in the late 1800s, no one suspected that people would live that long. Now people are living 20, 30, and 40 years longer than they expected—yet many have retired. For many, there are financial challenges of how they can support themselves for the rest of their life. For others, boredom from lack of any meaningful activity produces depression and changes in the relationship of husband and wife who were used to the husband being the working provider, while after retirement he has become a homebody.

Transcranial/transnasal approach for nonpituitary sellar lesions

Manas Panigrahi, Gangumolu Varaprasad — 2009-12-01

We read the article “Pituitary function after endonasal surgery for nonadenomatous tumors: Rathke's cleft cysts, craniopharyngiomas, and meningiomas’’ published in Surgical Neurology [70(2008)482-491]. It discussed endonasal approach to nonadenomatous parasellar tumors. The 3 pathologies studied are Rathke cleft cyst, craniopharyngioma, and parasellar meningiomas. The main aspect discussed is the pituitary function after endonasal surgery (the rates and risk factors of new hormonal failure and recovery).

Response

Daniel F. Kelly, Josh Dusick, Nasrin Fatemi — 2009-08-13

We appreciate the comments from Drs Panigrahi and Varaprasad regarding the relative merit of transcranial vs endonasal removal of Rathke’s cleft cysts, craniopharyngiomas, and tuberculum sellae meningiomas. They suggest that endonasal removal of Rathke cleft cysts is appropriate. However, they recommend removal of craniopharyngiomas and tuberculum sella meningiomas through a transcranial approach because subtotal removal, new endocrine deficits, visual loss, and CSF leaks are more frequent with the transsphenoidal route.

RE: Transcranial/transnasal for nonpituitary sellar lesions

Manas Panigrahi — 2009-12-01

I thank the authors of the article for the reply. It appears in conclusion that they agree to the concept of using the transcranial route for intracranial lesions such as meningiomas and craniopharyngiomas; where we differ, however, is with the advantages of using the endonasal route for smaller tumors with limited extension.

Anterior interosseous syndrome vs flexor pollicis longus tendon rupture: electrodiagnosis or sonography?

Murat Kara, Fevziye Ünsal Malas, Bayram Kaymak, Levent Özçakar — 2009-12-01

A 56-year-old woman, with a likely diagnosis of right anterior interosseous nerve (AIN) entrapment, was admitted for electrodiagnostic evaluations. On detailed questioning, she declared that she was unable to flex her right thumb at the interphalangeal joint (IJ). Furthermore, she could not write or hold an object properly in the last 2 months. She also described a swelling 2 months ago in the right thenar region where she had had intermittent pain for about 2 years. Her medical history was noncontributory except hypertensive nephropathy. On physical examination, there was no active flexion at the IJ of the right thumb, and the phalanx was in extended position. She was able to flex the distal IJ of the second and third digits though. A pathologic condition of the flexor pollicis longus (FPL) rather than an AIN palsy was considered, and sonographic evaluation was performed accordingly. Right thenar area muscles were normal, but FPL tendon could not be visualized proximal to the one half of the thenar region (). Electrophysiologic testing was normal. The patient was referred to orthopedic surgery with a diagnosis of complete FPL tendon rupture.

Re: The neuroprotective effect of dexmedetomidine in the hippocampus of rabbits after subarachnoid hemorrhage (Cosar et al. Surg Neurol 2009;71:54-59)

Paul S. Slosberg — 2009-07-16

I read with great interest this important article. More than 50 years ago , the catecholamine-depleter reserpine was included as a major hypotensive medication in the introduction (1956) of the medical-hypotensive program for intracranial bleeding with special emphasis on subarachnoid hemorrhage due to ruptured aneurysm(s). No difficulties with reserpine were encountered despite its usage over many years, very likely because of intensive monitoring, since this form of treatment had not been attempted before. In 1964, Dr Arthur Ecker, the neurosurgeon, who, with Dr Paul Riemenschneider, were the first to describe cerebral vasospasm , wrote to me concerning this medical approach, was kind enough to visit and review angiograms of my patients so treated and confirmed the frequent presence of vasospasm. I discussed his consultation along with the possibly protective role of reserpine in a presentation at the American Neurological Association Meeting in 1979, and this was published subsequently in the Transactions . Reserpine parenterally was a potent drug but, it is emphasized, when monitored closely caused no problems at all and, despite the presence of vasospasm (sometimes marked), the patients made, and maintained, long-term excellent recoveries .

James I. Ausman — 2009-10-16

Alberstone and colleagues have written an outstanding clinical anatomical text that is easy to read, excellently illustrated, succinct, and practical. It is one of the best clinical neuroscience texts I know. All neurologists and neurosurgeons should own one.

Addendum to “In this issue…”

James I. Ausman — 2009-12-01

On November 17, 2009 I received this note from the publisher:“Please note that a number of articles that you accepted for publication in Surgical Neurology will need to be published in the December issue. These are in addition to the articles you previously assigned to the issue.”

Quantitative analysis of motor neurons of the levator ani muscle in fetal rats with spina bifida occulta

Yong Li, Xiang-Yu Hou, Zheng-Wei Yuan, Wei-Lin Wang — 2009-03-31

Abstract: Background: With the combination of microsurgery and microinjection techniques, we investigated the development of motor neurons in the spinal cord of fetal rats with spina bifida occulta by injecting the retrograde trace FG into the levator ani muscle.Methods: The fetal rats were divided into 3 groups. On the day 9 of gestation, 6 mature Wistar rats (weighing 250-300 g) in the control group (group 1) were subcutaneously injected with 0.5 mL of normal saline at their hind limbs at 9:00 am and 4:00 pm. At these 2 time points, 15 rats in the treatment group (group 2 and group 3) were subcutaneously injected with 20% sodium valproate solution (400 mg/kg of body weight) at their hind limbs, too. On the day 20 of gestation, pregnant rats were anesthetized with 10% chloral hydrate (300 mg/kg of body weight) intraperitoneally, and then fetal microsurgery and microinjection were performed to expose the levator ani muscle, whereas 5% FG was administered with microinjector. Twenty-four hours later, transcardial perfusion of 4% paraformaldehyde in phosphate-buffered saline (PBS) was given to the operated fetus. After the spine sample was stained with Alcian blue GX, the image of stained spine was measured using a computer system for the distance of the 2 cartilaginous ends of the vertebra arch. Then, the lumbosacral spinal cord was cryopreserved in 20% sucrose in PBS for a later serial transverse cryosection after 24 hours. The FG-labeled motor neurons were visualized with a wide-band ultraviolet-fluorescent filter, and the number of the FG-labeled motor neurons was recorded. Nine fetal rats survived in group 1. Eighteen fetal rats survived in the treatment group, including 7 (with no malformation) of 18 fetuses in group 2 and 11 fetuses with spina bifida occulta in group 3.Results: The FG-labeled motor neurons in the ventral horn of normal spinal cord clustered at the dorsolateral and dorsomedial corner of the ventral horn. The FG-labeled motor neurons in the ventral horn of deformed spinal cord were less than that of normal spinal cord, and the motor neurons were scattered around the space between the dorsomedial and dorsolateral corners. The number of FG-labeled motor neurons was 244 ± 41 in group 3, 426 ± 36 in group 1, and 397 ± 20 in group 2. The data were stastistically significant if P < .05.Conclusion: The motor neurons that innervate the levator ani muscle in fetal rats with spina bifida occulta are fewer than the normal fetal rats, and they are arranged in abnormal distribution.

Commentary

Frank Van Calenbergh — 2009-03-31

The authors have made a nice experimental study of motor neuron development in the spinal cord of fetal rats with spina bifida. This is important information for all pediatric neurosurgeons and pediatric neurologists working in the field of spina bifida and tethered cord. The study may have clinical relevance for patients with tethered cord and lumbosacral lipoma; if the findings can be extended to humans, an abnormally low number of motor neurons probably partially explains why normalization of motor function does not occur often after untethering.

Commentary

Graciela N. Zuccaro — 2009-03-31

Many articles have been published that investigate the motoneuron development of the spinal cord in animal fetuses with spina bifida aperta. However, studies on motoneuron development in spina bifida occulta are scarce.

Resolution of syringomyelia after release of tethered cord

Andrew R. Hsu, Lewis C. Hou, Anand Veeravagu, Patrick D. Barnes, Stephen L. Huhn — 2009-07-16

Abstract: Background: Syringomyelia is an abnormal cystic dilatation of the spinal cord caused by excessive accumulation of CSF. Patients can develop various neurologic deficits secondary to untreated syringomyelia, some of which can be permanent despite surgical intervention.Case Description: The authors present a patient with syringomyelia, aortic coarctation, and tethered cord syndrome. Serial radiographic imaging demonstrated initial significant reduction of the thoracic syrinx after coarctation repair and release of tethered cord. However, subsequent follow-up imaging revealed partial recurrence.Conclusion: This case provides evidence of a possible cause-effect relationship between syringomyelia and tethered cord. It demonstrates the indication of surveillance imaging of the entire spine to ensure that all potential etiologies of syringomyelia are identified and treated. Furthermore, it illustrates the complex dynamic nature of syrinx physiology and reinforces the importance of serial follow-up studies after surgical intervention.

Acute surgical removal of low-grade (Spetzler-Martin I-II) bleeding arteriovenous malformations

2009-07-15

Abstract: Background: Early surgical removal of cerebral AVMs is a relatively infrequent therapeutic option when dealing with a cerebral hemorrhage caused by AVM rupture: even in the case of low-grade AVMs, delayed treatment is, if possible, preferred because it is considered safer for patients and more comfortable for surgeons. To assess whether acute surgery may be a safe and effective management, we conducted a retrospective analysis of our early surgery strategy for ruptured low-grade AVMs.Methods: We reviewed 27 patients with SM grade I-II AVM treated during 2004 to 2008 in the acute stage of bleeding (within the first 6 days after bleed). All patients showed a cerebral AVM on DSA at admission, and surgical removal was controlled by postoperative angiography. Neurological outcomes were assessed with GOS. The average length of follow-up was 22 months (48-3 months).Results: Before surgery, 16 (59%) patients showed a GCS of 8 or less, 2 of them presenting an acute rebleeding after first hemorrhage. All patients underwent radical AVM surgical removal and hematoma evacuation in a single-stage procedure. Most patients (78%) were operated within the first day of hemorrhage. A favorable functional outcome (GOS: good recovery or moderate disability) was observed in 23 patients (85%). Mortality was 7.4%. Outcome was not significantly correlated with GCS at presentation and with presence of preoperative anisocoria.Conclusions: Early surgery for grade I-II AVMs is a safe and definitive treatment, achieving both immediate cerebral decompression and patient protection against rebleeding, reducing time of hospital stay and allowing a more rapid rehabilitative course whenever necessary.

Initial clinical experience with image-guided linear accelerator-based spinal radiosurgery for treatment of benign nerve sheath tumors

2009-07-16

Abstract: Background: Stereotactic radiosurgery has proven a safe and effective treatment of cranial nerve sheath tumors. A similar approach should be successful for histologically identical spinal nerve sheath tumors.Methods: The preliminary results of linear accelerator–based spinal radiosurgery were retrospectively reviewed for a group of 25 nerve sheath tumors. Tumor location was cervical 11, lumbar 10, and thoracic 4. Thirteen tumors caused sensory disturbance, 12 pain, and 9 weakness. Tumor size varied from 0.9 to 4.1 cm (median, 2.1 cm). Radiosurgery was performed with a 60-MV linear accelerator equipped with a micro-multileaf collimator. Median peripheral dose and prescription isodose were 12 Gy and 90%, respectively. Image guidance involved optical tracking of infrared reflectors, fusion of amorphous silicon radiographs with dynamically reconstructed digital radiographs, and automatic patient positioning. Follow-up varied from 12 to 58 months (median, 18).Results: There have been no local failures. Tumor size remained stable in 18 cases, and 7 (28%) demonstrated more than 2 mm reduction in tumor size. Of 34 neurologic symptoms, 4 improved. There has been no clinical or imaging evidence for spinal cord injury. One patient had transient increase in pain and one transient increase in numbness.Conclusions: Results of this limited experience indicate linear accelerator–based spinal radiosurgery is feasible for treatment of benign nerve sheath tumors. Further follow-up is necessary, but our results imply spinal radiosurgery may represent a therapeutic alternative to surgery for nerve sheath tumors. Symptom resolution may require a prescribed dose of more than 12 Gy.

Commentary

Robert Goodkin — 2009-07-16

Advancements in radiosurgery have led to its use for the treatment of benign nerve sheath tumors and meningiomas in the spinal area, and literature regarding its use is beginning to be seen in the journals. Selch et al, in their article entitled “Image-Guided Linear Accelerator–Based Spinal Radiosurgery for Treatment of Benign Nerve Sheath Tumors,” present their experience regarding 20 patients with 25 nerve sheath tumors that were treated with spinal radiosurgery. The indications for spinal radiosurgery as noted by the authors included patients who refused surgical intervention or had recurrent or residual disease after surgery or were judged to be inoperable due to comorbid conditions.

Freehand C1 lateral mass screw fixation technique: our experience

2009-10-12

Abstract: Background: Although C1 lateral mass fixation technique is frequently performed in upper cervical instabilities, it requires the guidance of fluoroscopic imaging. The fluoroscopy guidance is time-consuming and has the risks of accumulative radiation. Biplane fluoroscopy is also difficult in upper cervical pathologic conditions because of the use of cranial fixations. This study aimed to demonstrate that unicortical C1 lateral mass screws could be placed safely and rapidly without fluoroscopy guidance.Methods: Between 2002 and 2008, 32 C1 lateral mass screws were inserted in 17 consecutive patients with various pathologic conditions involving either atlantoaxial or occipitocervical instability.Results: C1 screw lengths ranged from 18 to 32 mm. The atlantoaxial fixation was performed in 13 patients, and C1 lateral mass screws were added to the occipitocervical construct in 3 patients, to the posterior cervical construct in 2 patients, and to the cervicothoracic construct in 1 patient. In 2 patients, because C1 lateral mass screws could not be inserted unilaterally, C1 pedicle screw analogs were inserted. There were no screw malpositions or neurovascular complications related to screw insertion. Operation time and intraoperative bleeding of the isolated atlantoaxial fixations were retrospectively evaluated. The mean follow-up was 32.3 months (range, 7-59 months). No screw loosening or construct failure was observed within this period. Postoperatively, 4 patients complained of hypoesthesia, whereas one patient had superficial wound infection.Conclusion: C1 lateral mass screws may be used safely and rapidly in upper cervical instabilities without intraoperative fluoroscopy guidance and the use of the spinal navigation systems. Preoperative planning and determining the ideal screw insertion point, the ideal trajections, and the lengths of the screws are the most important points.

Clinical evaluation and follow-up outcome of presurgical plan by Dextroscope: a prospective controlled study in patients with skull base tumors

De L. Yang, Qi W. Xu, Xiao M. Che, Jin S. Wu, Bin Sun — 2009-10-22

Abstract: Background: Patient-specific approach design, comprehensive evaluation on perioperative data, and follow-up of postoperative life quality (KPS) were carried out to evaluate the application of VR technology of Dextroscope in procedures of patients with skull base tumors.Methods: Eighty-four patients with skull base tumors involved in this research were randomized into 2 groups (test group and control group), each with 42 patients. Before operation, image data such as MR, MRA, or CTA of head were collected and imported into the Dextroscope workstation. The detailed preoperative plans were made in the test group, but no Dextroscope plans in control group. The resection rate of tumors, preoperative evaluation including the duration of operation, total blood loss, the postoperative LOS, the number of cases with cerebrovascular injury complications in operation, and postoperative KPS of patients on discharge and the sixth month follow-up in the 2 groups were recorded and compared.Results: The total resection rate of tumors was 83.33% in test group and 71.42% in the control group (P > .05). The total resection rate of meningioma was 86.67% in test group and 76.47% in control group. The total resection rates of trigeminal Schwannoma in the 2 groups were all 100% (P > .05). The duration of operation and the postoperative LOS of each patient were 5.25 ± 0.64 hours and 8.50 ± 1.10 days in the test group and 7.36 ± 0.87 hours and 12.50 ± 1.52 days in the control group, respectively (P < .05). Total blood loss of each patient was 456.75 ± 55.76 mL in the test group and 523.85 ± 66.78 mL in the control group (P > 05). There were 3 cases with complications of cerebral vessels injury in the test group and 7 cases in the control group (P < .05). During follow-up, KPS of patients in the test group on discharge (85.75 ± 9.68) was significantly superior to that in the control group (81.66 ± 9.24; P < .05). The KPS of patients on the sixth-month follow-up in the test group was 92.35 ± 9.95, which was significantly superior to that in the control group (85.6 ± 9.34; P < .05). Karnofsky performance scores of patients in the test group improved significantly from discharge to the sixth month after procedure (P < .05), whereas there were adverse results in the test group (P < .05). The 2 cases with CSF leakage were cured completely.Conclusion: The preoperative plans with VR technology in patients with skull base tumor or CSF leakage operations can help certain the diagnosis, individually locate the position of skull base lesions, and design patient-specific approach, which also facilitate to shorten operation duration and the postoperative LOS, reduce total blood loss and injury of vessels in operation, and improve the postoperative KPS.

Commentary

Johnny B. Delashaw — 2009-10-23

This article emphasizes that preoperative planning can assist the surgeon in the operative approach and the abnormal anatomy that will be encountered. Although I think outcome is frequently determined by the experience of the surgeon, planning of potential anatomical variants can only help the surgeon improve outcome. This article emphasizes that VR with surgical planning can be very helpful.

Extracranial-intracranial bypass surgery at high magnification using a new high-resolution operating microscope: technical note

Nobuhisa Matsumura, Takashi Shibata, Kimiko Umemura, Seiya Nagao, Yukio Horie — 2009-10-15

Abstract: Background: We report a precise technique for EC-IC bypass surgery using a stereoscopic high-resolution microscope at magnifications of 40× and 50×.Methods: A stereoscopic operating microscope (Mitaka MM50 Surgical Microscope; Mitaka Kohoki Co, Tokyo, Japan) was used in STA-MCA anastomosis. This microscope has 2 optical systems, a standard zooming system, a newly developed high-magnification system, and 4 fixed working distances of 200, 250, 300 and 350 mm, with highest magnifications of 50.4× at 200 mm and 40.3× at 250 mm. High resolution is achieved by a new lens design in the optical system, which makes the image of the object very clear at high magnification. The magnification can be changed depending on the circumstances in a given procedure. The STA-MCA anastomoses were performed using this microscope.Results: Very small vessels were observable, and arterial anastomosis could be performed precisely at high magnification. All anastomoses were patent on postoperative angiograms.Conclusions: Use of the new microscope allows visualization and manipulation of small vessels at high magnification and high resolution and may be very useful in EC-IC bypass surgery.

Microsurgical training on an in vitro chicken wing infusion model

Jon Olabe, Javier Olabe — 2009-03-31

Abstract: Background: Microneurovascular anastomosis and aneurysm clipping require extensive training before mastering the technique and are a surgical challenge. We developed the “infused chicken wing method” to provide a simple but realistic training method minimizing animal use and need for special facilities for animal care and anesthesia.Methods: Fresh chicken wings were used in this model. The main brachial artery was cannulated, and water was infused at 140 mm Hg followed by anatomical neurovascular dissection. Multiple microsurgical training exercises were performed under microscope vision including terminoterminal, lateroterminal, laterolateral vascular anastomosis, and nerve anastomosis. Different complexity aneurysms were created using venous patches, clipping, rupture, and vascular reconstruction techniques were performed.Results: This novel training model is inexpensive, easily obtainable, and no live animals are required. The diameter and characteristics of arteries and veins used are similar to those of the human brain. Great microsurgical technique progress may be obtained.Conclusions: The infused chicken wing artery model presents a realistic microvascular training method. It is inexpensive and easy to set up. Such simplicity provides the adequate environment for developing microsurgical technique.

Human cadaver brain infusion model for neurosurgical training

Jon Olabe, Javier Olabe, Vidal Sancho — 2009-08-07

Abstract: Background: Microneurosurgical technique and anatomical knowledge require extensive laboratory training before mastering these skills. There are diverse training models based on synthetic materials, anesthetized animals, cadaver animals, or human cadaver. Human cadaver models are especially beneficial because they are the closest to live surgery with the greatest disadvantage of lacking hemodynamic factors. We developed the “brain infusion model” to provide a simple but realistic training method minimizing animal use or needs for special facilities.Methods: Four human cadaveric brains donated for educational purposes were explanted at autopsy. Carotids and vertebral arteries were cannulated with plastic tubes and fixed with suture. Water was flushed through the tubings until the whole arterial vasculature was observed as clean. The cannulated specimens were fixed with formaldehyde. Tap water infusion at a flow rate of 10 L/h was infused through the arterial tubings controlled with a drip regulator filling the arterial tree and leaking into the interstitial and cisternal space.Results: Multiple microneurosurgical procedures were performed by 4 trainees. Cisternal and vascular dissection was executed in a very realistic fashion. Bypass anastomosis was created as well as aneurysm simulation with venous pouches. Vessel and aneurysm clipping and rupture situations were emulated and solution techniques were trained.Conclusion: Standard microsurgical laboratories regularly have scarce opportunities for working with decapitated human cadaver heads but could have human brains readily available. The human brain infusion model presents a realistic microneurosurgical training method. It is inexpensive and easy to set up. Such simplicity provides the adequate environment for developing microsurgical techniques.

Surgical technique for a cystic-type metastatic brain tumor: transformation to a solid-type tumor using hydrofiber dressing

Takeshi Okuda, Yoshifumi Teramoto, Haruki Yugami, Kazuo Kataoka, Amami Kato — 2009-10-16

Abstract: Background: Many metastatic brain tumors have a distinct border with normal brain tissue, which facilitates tumor removal. However, residual tumor tissue may be present after surgery when metastatic brain tumors are of cystic type. We have developed a method using hydrofiber dressing to transform cystic-type into solid-type tumors.Methods: Hydrofiber dressing is a sodium carboxymethylcellulose hydrocolloid polymer with high fluid-absorptive capacity. This material was originally used as a dressing for exudative wounds. Hydrofiber dressing was used for 8 patients with cystic-type metastatic brain tumor. Tumor removal was performed after hydrofiber dressing was inserted into the cyst cavity to transform the tumor into a solid-type tumor.Results: Transformation of cystic-type metastatic brain tumors into smaller solid-type tumors using hydrofiber dressing facilitated en bloc resection of tumor. The dressing also absorbed residual cyst fluid and was thus also effective in preventing intraoperative dissemination of tumor cells. This approach enabled ideal en bloc resection in all patients. There were no adverse events.Conclusions: These findings suggest hydrofiber dressing may be useful in surgery for cystic-type metastatic brain tumors.

Commentary

Kazuo Yamada — 2009-10-16

This article provides a new technical idea for the removal of cystic brain metastasis. For removal of cystic tumors, dissection from the surrounding brain is often difficult due to collapse of the tumor wall. Insertion of hydrogel into the tumor cavity is an attractive and reasonable idea to overcome this difficulty. The size and consistency of the mass can be controlled by the amount of hydrogel inserted along with applying saline, so that the surrounding brain has no additional injury during dissection. This technique can be applied to cystic tumors beyond metastasis.

Factors affecting the outcome after treatment for metastatic melanoma to the brain

Christopher J. Carrubba, Todd W. Vitaz — 2009-07-15

Abstract: Background: Because of the difficulties inherent to the treatment of metastatic melanoma to the brain including high rates of disease progression and local treatment failure, we attempted to determine the prognostic factors that impacted the outcome of these patients, and reviewed patient outcome based on primary treatment with either surgical resection or SRS.Methods: A retrospective review identified 37 patients treated for metastatic melanoma between July 2002 and April 2007. Information was obtained documenting systemic disease, preoperative symptoms, tumor size and location, disease recurrence, primary and secondary treatments, and survival time.Results: Two patients were alive as of March 2008. The median survival time for patients primarily treated with surgical resection was 9.7 months compared to 7.9 months for patients initially treated with SRS. Solitary brain metastases and the absence of both preoperative hemorrhage and lung metastases served as prognostic factors increasing survival in both groups. Four patients undergoing primary treatment with SRS required subsequent surgical intervention secondary to radiation necrosis (3 patients) or local recurrence (1 patient). All 4 had lesions greater than 1.5 cm. For surgical patients, planned postoperative treatment with either radiosurgery or radiation therapy increased survival time to 12.3 months vs 7.3 months.Conclusions: Patients with positive prognostic factors including solitary brain lesions, absence of hemorrhage preoperatively, and absence of lung disease are viable candidates for aggressive, surgical intervention followed by adjuvant therapy with radiosurgery or conventional radiation therapy. Other patients should be considered for more conservative treatment with radiosurgery or other palliative treatments.

Posterior fossa intracranial inflammatory pseudotumor: a case report and literature review

Yu-Jun Lin, Tzu-Ming Yang, Jui-Wei Lin, Ming-Ze Song, Tao-Chen Lee — 2009-07-16

Abstract: Background: Intracranial inflammatory pseudotumors are rare. This study describes an intracranial inflammatory pseudotumor at the left cerebellopontine angle. It is the second documented posterior fossa intracranial inflammatory pseudotumor, and it was treated by surgery and radiotherapy.Case Description: A 49-year-old man presented with dizziness for 3 months and mild hoarseness for 1 month. Brain CT detected an intracranial tumor at the left cerebellopontine angle. Magnetic resonance imaging revealed a 3.6-cm heterogeneously enhancing mass. Suboccipital craniectomy with ventriculostomy was performed. The mass was well defined with a smooth surface, enclosed the low cranial nerves, and adhered to the dura matter. Pathologic examination revealed fibrous collagenous stroma with dense infiltrates of small lymphocytes and uninucleated histiocytes. Immunopositivity for T-200 and CD-68 was noted. Special staining for mycobacteria and fungus was negative. Serologic tests were positive for EBEA-Ab, EBNA-Ab, and EB-VCA-IgG. An inflammatory pseudotumor was diagnosed. Local recurrence was found 6 months later with a left oculomotor nerve palsy. Whole-brain irradiation with a total dose of 1200 cGy in 6 fractionations was done. Remission was found in follow-up neuroimages, and no recurrence was noted in 2 years' follow-up.Conclusion: Based on serologic findings and a literature review, the pathogenetic mechanism of this rare intracranial tumor is believed to be chronic reactive EBV infection. We propose that radiotherapy may be the best treatment option in the case of local recurrent intracranial inflammatory pseudotumors.

Commentary

Mahmood F. Mafee — 2009-07-16

Pseudotumor is a nonspecific inflammatory process, which in the head and neck region not infrequently involves the orbit. Orbital pseudotumors may result in painful proptosis and other orbital symptoms. It can involve the orbital apex as well as the superior orbital fissure, resulting in clinical presentation of superior orbital fissure syndrome (Tolosa-Hunt syndrome). Involvement of other parts of the cranial space is very rare as presented by the author in this article. Intracranial pseudotumors can involve the epidural (cranial and spinal) as well as dural covering. Intraaxial pseudotumors are extremely rare. When the spinal epidural space is involved, based on imaging, one should also include the possibility of metastasis, amyloidosis, and extramedullary hematopoiesis.

Dermoid tumor with diastematobulbia

Krishna Prabhu, Roy Thomas Daniel, Sunithi Mani, Ari G. Chacko — 2009-07-16

Abstract: Background: Dermoid tumors are rare congenital lesions and account for 0.2% to 1.8% of all intracranial tumors. Dermoid tumor with diastematobulbia is very rare.Case description: We report a dermoid tumor in an adult female with an unusual location and morphology. The lesion had 2 major components with different material within the cysts. The posterior part of the dermoid had presented on the floor of the fourth ventricle and had split the pons into 2 distinct halves. The anterior part of the lesion was situated in the prepontine cistern and encircling the anterior half of the brainstem. The lesion was radically excised, and the postoperative images showed return of the 2 halves of the pons to appose each other in the midline.Conclusion: This case report demonstrates the anatomical peculiarities of this extremely unusual presentation of a dermoid cyst with diastematobulbia. Total excision of the lesion through a dorsal approach resulted in a good outcome.

Commentary

Alexandru Vladimir Ciurea — 2009-07-16

Dermoid cysts are very rare lesions representing less than 1% of all intracranial tumors. Only isolated cases were published in the last years . A classification into 4 groups was developed by Longue and Till (1952) , whereby the formed groups depend on the extradural or intradural localization of the cyst and on the degree of development of the dermal sinus.

Successful treatment of intraorbital lymphangioma with tissue fibrin glue

2009-10-15

Abstract: Background: Although surgical resection is the first treatment choice in patients with cystic lymphangioma, the complete resection of orbital lymphangioma is often difficult. After partial resection of the cyst wall, some cystic lymphangiomas recur. The injection of tissue fibrin glue may prevent the recurrence of orbital lymphangioma.Case Description: We present a 2-year-old girl with left progressive exophthalmos. Magnetic resonance imaging revealed a cystic mass lesion behind the left eyeball. At the first operation, the cyst wall was partially resected, and all cyst fluid was totally removed by suction. One week after the first operation, the cyst showed regrowth. At a second procedure, we injected tissue fibrin glue into the cyst. The cyst was completely sealed, and there was no recurrence.Conclusion: Tissue fibrin glue is adhesive and hemostatic and highly useful in the treatment of orbital cystic lymphangioma.

Commentary

Joseph C. Maroon — 2009-10-15

Although rare in the practice of most neurosurgeons, this lesion is extremely difficult to eradicate and has a definite propensity for recurrence. The technique of injecting fibrin glue into residual cysts may have some benefit as suggested by the authors. Obviously, this one case does not provide proof positive, but it is an interesting consideration to keep in mind when operating on such a lesion.

Cerebral ischemia due to compression of the brain by ossified and hypertrophied muscle used for encephalomyosynangiosis in childhood moyamoya disease

Hajime Touho — 2007-10-29

Abstract: Background: Encephalomyosynangiosis is one of the indirect method in which ischemic brain surface is covered by temporal muscle for the treatment of moyamoya disease.Case Descriptions: A 14-year-old girl who had been treated with bilateral STA-MCA anastomosis and EMS in 1999 was admitted on January 5, 2005. She showed transient incomplete palsy on the left side of the face and the ipsilateral upper extremity. On the day of admission, MRIs/MRA and 3-dimensional regional CBF measurement using stable xenon and CT scanning were conducted after performance of plain CT scanning. The MRI and CT studies showed that ossified and hypertrophied temporal muscle used for EMS to the right MCA territory compressed the brain just under the muscle. MRA demonstrated well-developed collaterals to the territories of the bilateral MCAs via the previously performed anastomosis. The CBF studies disclosed a low CBF value just under ossified and hypertrophied muscle used for EMS on the right side. She showed same transient ischemic attacks repetitively after January 5, 2005.Conclusions: The repetitive attacks with the transient motor palsy on her left side was thought to be caused by direct compression of the brain by the ossified and hypertrophied muscle used for EMS and decrease in CBF just under it, and its removal was thought to be the treatment of choices. However, the patient and her parents refused the surgical procedure, and she is treated conservatively at present.

Multiple dynamic cavernous malformations in a girl: long-term follow-up

Liang Chen, Yao Zhao, Zheng Chen, May Tee, Ying Mao, Liang-Fu Zhou — 2009-07-15

Abstract: Background: Cavernous malformations have generally been viewed as fairly benign vascular lesions with low potential for causing massive hemorrhage.Case Description: We present an interesting case of multiple CMs, several of which were formed de novo and exhibited aggressive biological behavior resulting in recurrent episodes of intracranial hemorrhage over a 10-year period. This case illustrates a dynamic and aggressive form of CMs. Recent advances in our understanding of the molecular pathogenesis of CMs implicate genetics as an important pathogenic factor, which is the most likely etiology of this patient's presentation.Conclusion: Special challenges exist in managing young children with multiple, highly aggressive CMs.

Removal of cavernous malformation of the Meckel's cave by extradural pterional approach using Heros muscle dissection technique

Hakan Seçkin, Nirav Patel, Emel Avcı, Robert J. Dempsey, Mustafa K. Başkaya — 2009-07-16

Abstract: Background: We report on a patient with trigeminal neuralgia caused by an extraaxial cavernous malformation (CM) located within Meckel's cave. The lesion was removed via a pterional extradural approach with a modified temporalis muscle dissection technique, which was first described by Heros and Lee. Cadaveric dissections were performed to demonstrate the wider exposure gained by this approach.Methods: A 56-year-old man presented with a history of episodic shocklike, right-sided facial pain for 10 years. Neurologic examination revealed diminished sensation in the mandibular division of the right trigeminal nerve. Magnetic resonance imaging showed an ipsilateral enhancing lesion in Meckel's cave.Results: After placement of a lumbar drain, a right extradural pterional approach was undertaken. By reflecting the temporalis muscle posterolaterally, the craniotomy was extended so that the line of sight was level with the floor of the middle fossa. This allowed access to the lesion without needing to remove the zygoma. The lesion was resected with microsurgical technique. The patient's pain improved significantly after resection, and histopathologic examination confirmed the diagnosis of CM.Conclusions: Extraaxial middle fossa CMs arising solely from Meckel's cave are rare. These lesions are safely and simply approached by posteriorly deflecting the temporalis muscle during a pterional craniotomy, avoiding excessive elevation of the anterior temporal lobe or further bony removal.

Commentary

Liang Chen, Liang-Fu Zhou — 2009-07-16

The modified epidural approach to the Meckel's cave is well illustrated through anatomical dissection. The modification includes partial interruption of the temporal muscle at the zygomatic level, which enables a closer surgical view to the middle cranial fossa and spares orbitozygomatic removal. We believe this approach is applicable and efficient in clinical tumor resection.

Distal intracranial catheterization of patients with tortuous vascular anatomy using a new hybrid guide catheter

2009-07-16

Abstract: Background: A hybrid guide catheter mates the traditional strong guide catheter with a thin, soft distal tip, allowing placement further into the distal cervical or proximal cranial circulation.Case Description: We present 5 cases in which traditional guide catheters were unable to successfully navigate tortuous anatomy or provide stable support for intervention.Conclusion: Hybrid guide catheters provided safe, stable support for successful treatment. Hybrid guide catheters allow for treatment for patients who previously were not candidates for neuroendovascular surgery.

Commentary

Nestor R. Gonzalez — 2009-07-16

This is an interesting report of the use of the new Neuron (hybrid guide) catheters in endovascular navigation of tortuous vessels. The authors report 5 successful cases where the additional support obtained with these new catheters played a significant role in allowing endovascular treatment for these patients. Their discussion of the mechanics of this improvement is appealing, and the results they observed are similar to our experience with the use of this new technology.

Emergency endovascular Stent graft and coil placement for internal carotid artery injury during transsphenoidal surgery

Young Seok Park, Jin Young Jung, Jung Yong Ahn, Dong Jun Kim, Sun Ho Kim — 2009-07-15

Abstract: Background: An internal carotid artery (ICA) injury is an uncommon but potentially fatal complication of transsphenoidal surgery.Case Description: We report a 61-year-old male patient with a right cavernous ICA injury sustained during transsphenoidal surgery and who underwent endovascular Stent graft placement. The ICA trapping was not indicated because of the absence of the left A1 on preoperative magnetic resonance angiography. During Stent graft placement, the ICA wall could not be completely fit with a stent due to its stiff nature and the carotid curve. The gap between the stent and the ICA wall was filled using a coiling procedure on the first postoperative day.Conclusions: Endovascular Stent graft placement for posttranssphenoidal carotid artery injury is a useful technical adjunct to the management strategy and has the potential to minimize the risk of having to sacrifice the ICA. In cases of incomplete reconstruction of the Stent graft placement due to its stiff nature and the carotid curve, an additional coiling procedure could be helpful to obliterate the gap between the stent and the ICA wall. To avoid carotid injury during transsphenoidal surgery, careful preoperative evaluation of vascular structures and meticulous surgical technique are necessary.

Implant design may influence delayed heterotopic ossification after total disk arthroplasty in lumbar spine

Eubulus J. Kerr, Ajay Jawahar, Stephen Kay, David A. Cavanaugh, Pierce D. Nunley — 2009-12-01

Abstract: Background: As total disk arthroplasty (TDA) gains increasing acceptance as an alternative to fusion for degenerative disk disease of the lumbar spine, new complications are encountered by the physicians during and after the procedure. We hereby report a complication after TDA in the lumbar spine that is in variance from previously proposed theories and suggests the possibility of implant design as one of the etiologic factors. The purpose of the present submission is to report a case of delayed heterotopic ossification (HO) after TDA that suggests that the keel-based design of the implant might have contributed to the etiology.Case description: The patient underwent TDA for L3-4 degenerative disk disease and had fusion surgery for L5-S1 disease about 6 months later. During follow-up, development of significant HO was noticed at the L3 and L4 level. Radiologic studies revealed the origin of HO to be the keel cut made in the body of L3 to accommodate the keel-based artificial disk.Conclusion: The exact etiology of HO after TDA is not clear. The presented anecdote points toward vertebral body trauma due to the design of the implant as a possible factor that needs to be studied more elaborately.

Commentary

William C. Welch — 2009-12-01

The authors of this article report on the development of heterotopic ossification and attribute it to end plate trauma during disk arthroplasty insertion. Although this may not be a common occurrence, it is one that surgeons need to be aware of when choosing to perform total disk arthroplasty. The authors recognize that a possible contributing factor for the development of heterotopic ossification in this patient may have been the use of a device with a keel.

En bloc sacrectomy and reconstruction: technique modification for pelvic fixation

C. Benjamin Newman, Sassan Keshavarzi, Henry E. Aryan — 2009-08-10

Abstract: Background: When the management of sacral tumors requires partial or complete sacrectomy, the spinopelvic apparatus must be reconstructed. This is a challenging and infrequently performed operation, and as such, many spine surgeons are unfamiliar with techniques available to carry out these procedures.Case Description: A 34-year-old man presented with severe low back pain, mild left ankle dorsiflexion weakness, and left S1 paresthesias. Imaging revealed a large sacral mass extending into the L5/S1 and S1/S2 neural foramina as well as the presacral visceral and vascular structures. Needle biopsy of this mass demonstrated a low-grade chondrosarcoma. A 2-stage anterior/posterior en bloc sacrectomy with a novel modification of the Galveston L-rod pelvic ring reconstruction was carried out. Our modification takes advantage of new materials and implant technology to offer another alternative in reconstruction of the spinopelvic junction.Conclusion: Understanding the anatomy and biomechanics of the spinopelvic apparatus and the lumbosacral junction, as well as having a familiarity with the various techniques available for carrying out sacrectomy and pelvic ring reconstruction, will enable the spine surgeon to effectively manage sacral tumors.

Commentary

Howard Morgan — 2009-08-10

This case report by Newman et al of a technique modification is to be admired for the multidisciplinary approach to a challenging and complicated disease process. Considerable resources and efforts went into trying to salvage the life and ambulatory function of one patient. The monetary costs were no doubt sizable as well as the “man hours” required. Permanent loss of bowel and bladder voluntary sphincter control as well as sexual function might not be acceptable to all patients. Of interest from a neurologic functional and anatomical standpoint is that sacrifice of all nerve roots distal to the L5 roots bilaterally resulted in only 4/5-ft plantar flexor weakness.

Rhabdomyolysis after transnasal repair of anterior basal encephalocele

2009-07-15

Abstract: Background: Postoperative Rhabdomyolysis (RM) is rare after neurosurgical procedures. Furthermore, it has not been observed after transnasal approaches. The authors report a case of idiopathic RM occurring after transnasal resection of a sincipital encephalocele.Case Description: A 32-year-old woman underwent a transnasal resection of a sincipital encephalocele after 6 years of intermittent clear nasal drainage. Postoperatively, she experienced severe back pain, peripheral neuropathy, associated with a markedly elevated creatinine kinase, and severe RM. The patient was treated with hydration and forced urine alkalization and treated symptomatically for her pain and neuropathy. She ultimately made a full recovery without complication.Conclusion: Rhabdomyolysis is a rare but known complication of neurosurgical procedures. We report the first known case report of RM after a transnasal procedure. Furthermore, a review of documented postneurosurgical cases of RM is presented and reveals that the causes and risk factors for this complication after neurosurgery are similar to those in other surgical subspecialties.

Cervical osteomyelitis and epidural abscess treated with a pectoralis major muscle flap

Masaki Fujioka, Kiyoshi Oka, Riko Kitamura, Aya Yakabe — 2009-08-10

Abstract: Background: Spinal osteomyelitis and epidural abscess are uncommon but have a potentially disastrous outcome, although the surgical techniques and antimicrobial therapy have advanced.Case Description: We present a case of cervical osteomyelitis and epidural abscess resulting from pharyngeal squamous cell carcinoma ablation, which were treated with a pectoralis major muscle flap successfully.Conclusion: Muscle flap insertion to the cervical contaminated wound enables radical removal of the contaminated tissue, and the muscle flaps for dead-space obliteration and neovasculation were obligatory for successful management of the infected complex wound. Furthermore, the inserted pectoralis major muscle flap can divide vertebrae and epidural canal from these origins of infection. We believe that this technique is simple, can be performed in a one-stage management, has minimal associated morbidity, and thus, is advocated as a desirable treatment option in the treatment of cervical osteomyelitis and epidural abscess.

Commentary

Langston Tyler Holly — 2009-08-10

The authors describe their experience using a pectoralis muscle flap in the treatment of cervical osteomyelitis and epidural abscess. This is a relatively novel procedure but appears to have had an excellent clinical and radiographic result. It is likely that this technique is not required for all cases of osteomyelitis and epidural abscess but may be a useful adjunct in some complex cases.

Commentary

William Charles Welch — 2009-08-10

The authors provided a case report dealing with the successful management of cervical osteomyelitis through the use of a rotational flap. Wound complications and their subsequent complications can have devastating consequences. The surgeon dealing with these issues needs to keep an open mind as to their treatment options. Rotation flaps are frequently very successful in these situations and should be considered in the decision tree for infection management.

Intramedullary spinal cysticercosis cured with medical therapy: case report and review of literature

2009-10-12

Abstract: Background: Spinal intramedullary cysticercosis is a very uncommon manifestation of NCC, which is caused by the larvae of Taenia solium.Case description: We report a case of spinal intramedullary cysticercosis who presented subacutely. Magnetic resonance imaging dorsal spine and CSF ELISA clinched the diagnosis. Eight weeks of medical therapy resulted in complete clinicoradiological cure.Conclusion: Surgery used to be the mainstay treatment for spinal intramedullary cysticercosis; however, early diagnosis and medical therapy with albendazole and dexamethasone can obviate the need for surgery in many patients.

Commentary

Julio Sotelo — 2009-10-12

Medical therapy has prevented surgical intervention in countless cases of neurosurgery. In endemic countries, neurosurgery is now reserved only for patients with hydrocephalus and for those cysts resistant to drug therapy—thus greatly reducing the costs and complications. The case reported by Singh et al documents with MRI the successful elimination of the parasite with albendazole and the total recovery of the patient after a cysticercus located in a rather delicate and clinically expressive area, the spinal cord. This report strengthens the current experience in most centers that the inflammation triggered by the sudden destruction of the parasite can be effectively neutralized with the addition of steroids to the antiparasitic treatment.

Severe hypotension with intracisternal application of papaverine after clipping of an intracranial aneurysm

2009-07-15

A 52-year-old hypertensive man presented with sudden-onset severe headache. Plain computed tomography (CT) of the head showed suprasellar cisternal subarachnoid hemorrhage (SAH) with intraventricular extension (). Computed tomography angiography revealed a left carotico-ophthalmic aneurysm. (). The patient was operated on the next day under World Federation of Neurological Surgeons grade 1 and the aneurysm was clipped. There was no intraoperative rupture or any temporary clipping. Post clipping, intraoperative Doppler showed normal flow in the distal carotid artery. Lamina terminalis was opened. Intracisternal papaverine (2 mL of papaverine [3%] diluted to 20 mL) was instilled. Within 2 minutes of papaverine instillation, the blood pressure dropped to 110/70 mm Hg from 140/80 mm Hg. Dopamine was started, but blood pressure (BP) continued to fall. Central venous pressure was raised to 12 cm of normal saline and dobutamine (10 μg/kg per minute) and noradrenaline (0.15 μg/kg per minute) were also added but BP fell to 50 mm Hg. After infusing 2 .0 L of crystalloid and 0.5 L of colloid, BP rose to a mean of 70 mm Hg. Continuous electrocardiographic monitoring throughout this period did not show any cardiac event or wave changes. The patient was kept on ventilation. Blood pressure started improving within 12 hours and all vasopressors were stopped within 48 hours. During this period, serial electrocardiogram did not reveal any cardiac cause and troponin T was also negative. Computed tomography of the head after 24 hours did not show any infarct or increase in ventricular size. Patient improved to E4VTM4 status with no focal deficit but developed acute renal failure. Peritoneal dialysis was done. The patient continued deteriorating, and died on postoperative day 15. The relatives did not give consent for an autopsy.

A note from the publisher

2009-12-01

Surgical Neurology

Contents

Contents

Contents

In this issue…

A note of respect

A note of appreciation to the editorial board

A note of gratitude to the readers of Surgical Neurology

Power: how to get it and how to use it for the future

Technology or judgment?

Fuzzy Logic in neurosurgery: predicting poor outcomes after lumbar disk surgery in 501 consecutive patients

Commentary

Neuromodulation of the superior hypogastric plexus: a new option to treat bladder atonia secondary to radical pelvic surgery?

Preparing the ethical future of deep brain stimulation

Commentary

Psychiatric symptom changes after corticoamygdalohippocampectomy in patients with medial temporal lobe epilepsy through Symptom Checklist 90 Revised

Commentary

Comparison of postoperative cognitive function in patients undergoing surgery for ruptured and unruptured intracranial aneurysm

Commentary

The combined approach to intracranial aneurysm treatment

Commentary

Intracranial angioplasty with Gateway-Wingspan system for symptomatic atherosclerotic stenosis: preliminary results of 27 Chinese patients

Commentary

Single-center experience with the Neuroform stent for endovascular treatment of wide-necked intracranial aneurysms

A rabbit model for efficacy evaluation of endovascular coil materials

Commentary

Do we need a neurosurgical Interpol?

Wound-peritoneal shunts: part of the complex management of anterior dural lacerations in patients with ossification of the posterior longitudinal ligament

Commentary

Commentary

Attempting homicide by inserting sewing needle into the brain: Report of 6 cases and review of literature

Commentary

What will you do with the rest of your life?

Transcranial/transnasal approach for nonpituitary sellar lesions

Response

RE: Transcranial/transnasal for nonpituitary sellar lesions

Anterior interosseous syndrome vs flexor pollicis longus tendon rupture: electrodiagnosis or sonography?

Re: The neuroprotective effect of dexmedetomidine in the hippocampus of rabbits after subarachnoid hemorrhage (Cosar et al. Surg Neurol 2009;71:54-59)

Addendum to “In this issue…”

Quantitative analysis of motor neurons of the levator ani muscle in fetal rats with spina bifida occulta

Commentary

Commentary

Resolution of syringomyelia after release of tethered cord

Acute surgical removal of low-grade (Spetzler-Martin I-II) bleeding arteriovenous malformations

Initial clinical experience with image-guided linear accelerator-based spinal radiosurgery for treatment of benign nerve sheath tumors

Commentary

Freehand C1 lateral mass screw fixation technique: our experience

Clinical evaluation and follow-up outcome of presurgical plan by Dextroscope: a prospective controlled study in patients with skull base tumors

Commentary

Extracranial-intracranial bypass surgery at high magnification using a new high-resolution operating microscope: technical note

Microsurgical training on an in vitro chicken wing infusion model

Human cadaver brain infusion model for neurosurgical training

Surgical technique for a cystic-type metastatic brain tumor: transformation to a solid-type tumor using hydrofiber dressing

Commentary

Factors affecting the outcome after treatment for metastatic melanoma to the brain

Posterior fossa intracranial inflammatory pseudotumor: a case report and literature review

Commentary

Dermoid tumor with diastematobulbia

Commentary

Successful treatment of intraorbital lymphangioma with tissue fibrin glue

Commentary

Cerebral ischemia due to compression of the brain by ossified and hypertrophied muscle used for encephalomyosynangiosis in childhood moyamoya disease

Multiple dynamic cavernous malformations in a girl: long-term follow-up

Removal of cavernous malformation of the Meckel's cave by extradural pterional approach using Heros muscle dissection technique

Commentary

Distal intracranial catheterization of patients with tortuous vascular anatomy using a new hybrid guide catheter

Commentary

Emergency endovascular Stent graft and coil placement for internal carotid artery injury during transsphenoidal surgery

Implant design may influence delayed heterotopic ossification after total disk arthroplasty in lumbar spine

Commentary

En bloc sacrectomy and reconstruction: technique modification for pelvic fixation

Commentary

Rhabdomyolysis after transnasal repair of anterior basal encephalocele

Cervical osteomyelitis and epidural abscess treated with a pectoralis major muscle flap

Commentary

Commentary

Intramedullary spinal cysticercosis cured with medical therapy: case report and review of literature

Commentary

Severe hypotension with intracisternal application of papaverine after clipping of an intracranial aneurysm

A note from the publisher