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© Georg Thieme Verlag KG Stuttgart · New York
The True Distal Posterior Inferior Cerebellar Artery Aneurysm: Clinical Characteristics and Strategy for Treatment
07 April 2010 (online)
Objective: A series of aneurysms located at the 4th or 5th segment of the posterior inferior cerebellar artery (PICA) has not been previously reported in the literature. We report six such cases and analyze their clinical characteristics and outcomes from three different treatment strategies.
Material and Methods: We reviewed six patients with a diagnosis of distal PICA aneurysm. The following data were analyzed: age, sex, aneurysm size, Hunt-Hess grade at presentation, angiographic characteristics, and clinical treatment outcome determined by Glascow outcome scores (GOS). Treatments performed included clipping and wrapping, sacrificing the parent arteries of the aneurysms, and selective coiling.
Results: Six patients (5 females, 1 male; mean age: 61.2 years; mean aneurysm size: 6.2 mm) presented at our facility with subarachnoid hemorrhage (SAH) caused by aneurysm rupture. Two patients presented with Hunt-Hess grades 4 and 5; all others were in Hunt-Hess grades 2 or 3. One patient died before surgery. Treatment outcomes of the surviving five patients were as follows: three patients had GOS of 5, one improved by operation, and another died from re-bleeding after selective coiling.
Conclusion: Surgery for the true distal PICA aneurysm results in good clinical outcomes. Clipping or wrapping should be considered as the first choice for treatment, and sacrificing the parent artery of the distal PICA aneurysm is relatively safer than selective coiling. The type of parent artery and particularly the collateralization of its distal part should be considered as an essential factor to take into consideration when choosing a treatment strategy.
intracranial aneurysm - posterior inferior cerebellar artery - Hunt-Hess grade - parent artery occlusion - selective coiling - Glasgow outcome score
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Comments on the Article „The True Distal Posterior Inferior Cerebellar Artery Aneurysm: Clinical Characteristics and Strategy for Treatment” by Y. Zhou, Y. Kato, O. T. Olugbenga, S. Hirotoshi, K. Karagiozov, O. Masahiro, S. Amitendu, N. Makoto, K. Tetsuo
Treatment algorithms used in six patients suffering from subarachnoid hemorrhage caused by rupture of a saccular aneurysm on either the telovelo-tonsillar (4th) segment or the cortical (5th) segment of the posterior inferior cerebellar artery (PICA) are presented in a retrospective manner. Thirty-eight cases with similar aneurysmal locations were collected from the literature of the past 5 years, and the pooled clinical data were compared with those of the study.
The authors have tried to define a treatment protocol for this rather uncommon aneurysm form. They have come to the conclusions that clipping or wrapping should be considered as the first choice for treatment, and that sacrificing the parent artery of the distal PICA aneurysm is relatively safer than intrasaccular coiling. They also suggest to take into consideration the collateralization of the distal part of PICA as an essential factor when defining a treatment strategy.
However, due to the small number of patients and the retrospective nature of the study of clinically rather varying cases, the manuscript should be considered by neurosurgeons as not more than another anecdotal report of very interesting cases operated on with excellent results.
I think that selection of the actual treatment method should be based on an analysis of the following factors in every individual case: patient's admission condition, aneurysm shape; signifi cance of blood supply on the parent distal artery, collateral circulation; presence of cerebellar hematoma, blockage of CSF circulation, and round the clock avalilability of all surgical (endovascular) modalities.
Reply on the Article „The True Distal Posterior Inferior Cerebellar Artery Aneurysm: Clinical Characteristics and Strategy for Treatment” by Y. Zhou, Y. Kato, O. T. Olugbenga, S. Hirotoshi, K. Karagiozov, O. Masahiro, S. Amitendu, N. Makoto, K. Tetsuo
As pointed out there has been confusion about exact defi nition of distal PICA aneurysms. This article aims to clear the confusion about the defi nition and also tries to lay down guidelines for management of these aneurysms although the number of patients is small. The authors have attempted to some extent to fill these lacunae by reviewing other studies on PICA aneurysms.
The classification of these aneurysms makes the management protocol easier at the cost of having fewer patients in each group. Further studies are defi nitely required to validate these findings.
Department of Neurosurgery Xiehe Hospital
Tongji Medical College Huazhong
University of Science and Technology
People's Republic of China
Phone: +86 1532 7250 217
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