gms | German Medical Science

59th Annual Meeting of the German Society of Neurosurgery (DGNC)
3rd Joint Meeting with the Italian Neurosurgical Society (SINch)

German Society of Neurosurgery (DGNC)

1 - 4 June 2008, Würzburg

Posterior inferior cerebellar artery (PICA) aneurysm arising from a bihemispheric PICA

Aneurysma der Arteria cerebelli infrerior anterior (PICA) an einer bihemisphärischen PICA

Meeting Abstract

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  • corresponding author P.C. Reinacher - Neurochirurgie, Universitätsklinikum der RWTH Aachen
  • T. Krings - Neuroradiologie, Universitätsklinikum der RWTH Aachen
  • F. J. Hans - Neurochirurgie, Universitätsklinikum der RWTH Aachen

Deutsche Gesellschaft für Neurochirurgie. Società Italiana di Neurochirurgia. 59. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 3. Joint Meeting mit der Italienischen Gesellschaft für Neurochirurgie (SINch). Würzburg, 01.-04.06.2008. Düsseldorf: German Medical Science GMS Publishing House; 2008. DocP 063

The electronic version of this article is the complete one and can be found online at:

Published: May 30, 2008

© 2008 Reinacher et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: The PICA can be absent in up to 26% of patients; if so, its territory is typically annexed by a dominant AICA since both vessels are in a close reciprocal relationship. An alternative supply of the PICA territory is the contralateral PICA that can lead to a bihemispheric supply. We report a case of an aneurysm arising from a bilateral PICA.

Methods: In a 47-year-old female, during diagnostic workup for cervical radiculopathy related to the right C6 root, cervical MRI revealed a disc protrusion at C5/6. On T2 weighted images, a flow void of 8mm size was noticed in the PICA territory.

Results: 3D DSA demonstrated that the right supratonsillar PICA, after reaching the apex of its course in the choroidal point bifurcated into lateral hemispheric branches and medial branches to the vermis. Here the medial branch gave not only rise to the (unpaired) vermian artery but also continued to cross the midline along the dorsal aspect of the vermis. Due to the broad communication with the PICA and the potentially devastating results of a parent vessel occlusion by endovascular means, a surgical option was favoured that was carried out via a far lateral transcondylar sboccipital approach resulting in complete occlusion of the aneurysm with preservation of the bihemispheric PICA.

Conclusions: There are only six reported cases of bihemispheric PICA present in the literature, none of them being associated with an aneurysm. Extreme caution must be taken when treating an aneurysm located at the origin of a bilateral PICA since occlusion might lead to catastrophic bilateral posterior fossa infarctions. Surgery is a viable option especially if the communication of the aneurysm with the parent vessel is broad.