Aneurysms of the Distal Posterior Inferior Cerebellar Artery: Experience with Three Cases and Review of the Literature

Abstract

We report 3 surgically treated aneurysms of the distal posterior inferior cerebellar artery (PICA) and review 36 cases in the literature. More than half of the distal PICA aneurysms arose distal to the choroidal arch. These lesions often arose at a turning point (i.e., a hairpin curve) of an artery instead of at a junction of vessels. Distal PICA aneurysms are likely to be missed and it is necessary to investigate carefully with four-vessel angiography even if computed tomography is done. Eighty-two per cent of the surgically treated 39 patients had good recoveries and 8% had fair results. The mortality rate was 10%. Although clipping of the aneurysm neck is preferable, trapping is useful when neck clipping is impossible in segments distal to the choroidal arch.

Distal Aneurysms of Cerebellar Arteries: Incidence, Clinical Presentation, and Outcome of Endovascular Parent Vessel Occlusion

“…1,2 Only case reports or small case series have been published, and no precise information is available in the literature regarding the management of distal cerebellar artery aneurysms or the associated long-term results. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Several approaches have been proposed to surgically treat these aneurysms, depending on their size and location. Although direct clipping is possible in some cases, sophisticated surgical techniques such as hypothermic cardiac arrest and bypass construction are often needed.…”

Distal posterior inferior cerebellar artery aneurysm: case report

“…The pathogenesis of aneurysms in PICA is matter of discussion. It is well accepted that the site of prediction of general aneurysms are the arterial bifurcations; however, the great majority of aneurysms at the distal PICA are not related to its branches [3][4][5][6] . Hemodynamic stress at the hairpin curve of the PICA may play a role in branchless aneurysm formation 7 .…”

“…The majority of them are localized at the vertebral artery (VA) PI-CA junction [3][4][5] . There are few large series of distal PICA aneurysms [6][7] , with no more than 26 cases.…”

“…Predicting the site of the aneurysm with knowledge of the pattern of bleeding despite the absence of vasospasm is important because this kind of lesions can be missed in up to 21.7% of cases 7 , despite the absence of vasospasm 2 . Careful four-vessels angiography is always recommended 4 .…”

Aneurysm of the Distal Posterior Inferior Cerebellar Artery with Intraventricular Hemorrhage: A Case Report

“…Many small arteries arise from the medullary segment and go through the brainstem, so the aneurysm's location is important in the selection of which procedure-clipping or trapping-to use. If neck clipping had been difficult, we would have used proximal ligation or trapping3, 5,17,19,22,25) Hudgins et a1.3 and Lister et al 17 have reported that aneurysms arising from, or distal to, the telovelotonsillar segment might be treated with proximal trappings as brainstem perforators do not arise beyond this point.…”