The lead article in this issue is the next in the series of microsurgery for intracranial aneurysms by Hernesniemi and his “Rainbow Team” from Finland. This article, which is accompanied by 3 videos of about 4 minutes each, covers the Finnish experience of the authors with proximal anterior cerebral, A1A, aneurysms. The article is easy to read and contains the experience in dealing with 23 patients who had 23 aneurysms of the proximal A1, anterior cerebral artery, aneurysms. In Finland, where the incidence of ruptured intracranial aneurysms is higher than in other countries, different circumstances produce a surgical orientation to treating these aneurysms as opposed to endovascular management. The risks of surgery are lower than that seen in other places with less volume of cases. A1A aneurysms are found in less than 1% of all aneurysms; hence, there is not much written about this subject. Section 3 of the article, which discusses the Microsurgical Anatomical Considerations of A1As, is an important read for those operating on these lesions, as well as sections 5 and 6, which discusses Microsurgical Strategy with A1As and the Dissection and Clipping of A1As, respectively. These sections are full of good tips for the operating surgeon. The A1A aneurysms are small and fragile and may be difficult to treat by the endovascular route. This is another excellent article from the Rainbow Team and is a well worth read, plus seeing the videos.
Freitas et al in a multicenter study from Brazil and Mexico have written a first rate article on the treatment of intracranial arterial stenosis with a balloon expandable stent. The authors evaluated 33 patients with greater than 50% intracranial arterial stenosis in the anterior and posterior circulations. The patients were divided into 3 groups: one third, those with ischemic stroke; one third, those with ischemic stroke and transient ischemic attack; and one third, those with transient ischemic attack. The follow-up was about 8 months. There was 9.4% mortality and 6% nonfatal complication rate. However, the mean stenosis was reduced from 69% to 5%, and 9% had a restenosis of greater than 50% in follow-up. In the Discussion of this well-done and well-written study, the authors reviewed the other 2 studies in the literature. Their results compare very favorably. Intracranial arterial stenosis is a difficult disease to treat. Having developed posterior circulation bypass surgery for such lesions and having performed middle cerebral, intracranial vertebral, and mid basilar endarterectomies with little success, I firmly believe that endovascular approaches would have a better outcome and less risk than surgical ones. The authors of this study have shown that my conclusion was correct that endovascular treatment is the better therapy, although the follow-up in this article is short. Besides, in the foreseeable future, genetic and molecular treatments will be the real answers to this disease. By the middle of this century, and maybe much earlier, atherosclerosis will disappear as a human disease. Until that time, unless restenosis becomes an overwhelming problem, which it has not been in the cardiac literature, intracranial stenting is, in my opinion, the best alternative today to treat intracranial stenosis. This study from Latin America is outstanding.
Moro et al from Japan have done an excellent study on a confusing subject of hyponatremia after traumatic brain injury. The article is easy to read and informative. Table 1, which describes the incidence of hyponatremia in various types of brain injury, is very interesting and raises questions about the underlying molecular mechanisms activated in one type of injury vs another. The use of sodium supplementation is nicely described, as is the addition of mineralocorticoids to the treatment plan. The authors provide an understandable approach to managing hyponatremia. The Discussion is also an excellent read. Good paper; worthwhile.
Mathieu et al from the United States report on their experience using gamma knife radiosurgery (GKS) to treat multiple sclerosis patients with unilateral tremor. Their results are good for a difficult disease to manage, but not perfect. However, in the Discussion, the authors state that neither stereotactic surgery nor deep brain stimulation provides much better alternative; thus, GKS provides an alternative treatment in a diffuse, complex, progressing disease without being invasive. The authors continue to write about their unique innovative ideas for treatment of many clinical neurological problems. They make a strong case for GKS in the treatment of multiple sclerosis tremor.
Izawa et al from Japan report on the clinical presentation and treatment of cyst formations after radiosurgery for cerebral arteriovenous malformations. The article is practical, the Discussion is informative, and Lunsford's comments at the end summarize the approach to these problems: treat if necessary, by endoscopic fenestration of the cyst, use an Ommaya reservoir to intermittently drain the cyst, shunt, or watch clinically.
Boviatsis et al from Greece analyzed a series of 240 patients aged 19 to 64 years and 108 aged 65 to 84 years, all of whom underwent removal of supratentorial meningiomas. The older age group had a statistically higher incidence of postoperative hematoma formation and neurological deterioration after surgery. Although the “older” group had the same incidence of postoperative edema after surgery, the reasons for their neurological deterioration are not clear, except for the difficulty in rehabilitating an older person compared with a younger one. The authors do suggest that aggressive rehabilitation of the elderly and early ambulation are necessary to prevent deep venous thrombosis. These suggestions make sense. As the populations in Europe, China, Japan, and the United States ages and lives into their 80s and 90s, neurosurgeons will be operating more on the elderly population. That is the significance of this article. Twenty years ago, my colleagues and I published an article entitled “Geriatric neurosurgery” (Surgical Neurology 1987;28:10-16). We analyzed the mortality of patients older than 65 and 85 years undergoing a variety of neurosurgical procedures. In our series, the mortality was less than 10% similar to this report. The conclusion was that extra care must be given to treating elderly patients to insure a good outcome. The authors of this report make the same conclusion. Elderly patients need the same specialized care as infants, and the outcomes will then be favorable. The report of Boviatsis and his colleagues is worth reading.
Rabadan et al from Argentina discuss an important issue in the developing world, although Argentina is a very progressive country in South America. Should patients with brain tumors be operated given the financial restrictions of the economy and the limitation of resources, including social and rehabilitative services needed to treat them? The authors analyzed a series of patients who underwent 236 craniotomies. Only those with a Karnovsky Score of higher than 60 (ability to function independently) were operated. Patients in poor neurological conditions, preoperatively, had more complications, as did patients with grade III glioma. Apparently, it was more difficult to remove grade III glioma from the brain without producing a deficit as it infiltrated the adjacent tissue. In some countries, patients with presumptive diagnosis of a malignant brain tumor from imaging are not operated. This article shows that reasonably good outcomes can be achieved in a developing country in patients with brain tumors if the appropriate selection criteria are made and surgical care exercised.
Kikuta et al from Japan compared an inhalation anesthetic with intravenously administered propofol and the effect of each on intracranial pressure and cerebral blood flow. Basically, in a series of operations in 20 patients with moyamoya syndrome, the authors found that by using each anesthetic on the same patient, switching from one to the other during surgery, propofol lowered the intracranial pressure and improved the cerebral blood flow in the frontal regions. These 2 results suggest that propofol makes a good anesthetic agent not only in moyamoya syndrome but also in aneurysm surgery.
Bayrakli et al from Turkey analyzed chromosomal abnormalities in 7 patients with primary and recurrent chordomas. As Linda Liau comments at the end, the authors did find chromosomes that were abnormal in the primary tumors and the recurrences. One chromosomal abnormality was present only in the primary and not in the recurrent tumors. As the authors state, this work is descriptive. We do not understand how these genetic changes can influence chordoma growth, but this article is a beginning on the road to understanding the molecular mechanisms involved in tumor development.
Chen et al from Taiwan describe their experience with the endoscopic removal of thalamic hematomas that had ruptured into the ventricle. At the first stage of their operation, the authors used a polypropylene channel that was inserted into the parietal area and down to the hematoma. This approach is reminiscent of Pat Kelly's initial work on stereotactic resections of tumors through a wider speculum-like channel. Then, they removed the hematoma by advancing an endoscope down the polypropylene channel. They irrigated out the ventricular system. None of the patients needed cerebrospinal fluid shunts after the endoscopic removal. This is a nice technique. Read the article. In addition, the Discussion is a very interesting review of the literature on the results of intracerebral hematoma removal. They make a very good argument for early removal.
Read the article by Trapp et al from the United States on the laparoscopic treatment of anterior sacral meningoceles. This report presents a very good example of the appropriate use of endoscopy in neurosurgery; a good idea to treat this problem.
The article by Sahni et al from India reports the anatomical changes in brains of adults, children, and fetuses of differing developmental stages. For this report, they concentrated on the posterior communicating artery. Only one posterior communicating artery aneurysm was found, in a 38-year-old patient, in their series of 370 autopsied brains. This was a study on Indians from northwest India. Other authors they cited found a 10% incidence of aneurysms in autopsied brains from western India, with 1% located on the posterior communicating artery. No aneurysms were found in the brains of patients in South India. In northern India, there was a suggestion of almost 40% of autopsied brains with aneurysmal dilatations or aneurysms. Why the difference? This evidence would suggest that the difference is genetic. Read my editorial on the anthropological evidence for the migration of human ancestors out of Africa to populate every country on Earth.
What is twiddler's syndrome? I did not know. Read the case report by Geissinger and Neal from the United States. It has an implication for all implanted pacemaker surgeries.
Subarachnoid hemorrhage restricted to a cerebral sulcus may be a warning sign of a coming intracerebral hematoma in patients with cerebral amyloid angiopathy. Read the case report by Katoh et al from Japan for an explanation.
What is the harlequin syndrome? Kilincer et al from Turkey describe this syndrome as unilateral facial flushing and sweating. Like Horner syndrome, the cause must be sought in the descending sympathetic pathways in the cervicothoracic cord and in the cervical sympathetic ganglia. In this article, the cause was related to an intramedullary tumor at the cervicothoracic level. Read Kao's excellent explanation at the end of the article of this syndrome and how to treat it.
The article by Sahni et al from India, describing the variations in the incidence of aneurysms in different parts of India, reminded me of an interesting chapter in a book I am reading on the historical origins of Globalization entitled Bound Together by Nayan Chanda (Yale University Press. New Haven and London; 2007). DNA analysis has led to an understanding of the patterns of migration of the first humans from Africa to all parts of the world. Actually, the author contends that this migration was the first stage of globalization. The different migration patterns he describes can explain the genetic differences in countries from Finland to India, where the incidence of aneurysms goes from high to low. In addition, these variations tell us of the genetic basis for this and other diseases and can explain the differences found in aneurysm incidence in various parts of India. I have written a short summary of this DNA-determined migration of humans in my editorial as described by Chanda.
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