The Glossopharyngo-Cochlear Triangle-Part II: Case Series Highlighting the Clinical Application to High-Riding Posterior Inferior Cerebellar Artery Aneurysms Exposed through the Extended Retrosigmoid Approach
Document Type
Article
Abstract
BACKGROUND: Use of the far lateral transcondylar (FL) approach and vagoaccessory triangle is the standard exposure for clipping most posterior inferior cerebellar artery (PICA) aneurysms. However, a distal PICA origin or high-lying vertebrobasilar junction can position the aneurysm beyond the vagoaccessory triangle, making the conventional FL approach inappropriate. OBJECTIVE: To demonstrate the utility of the extended retrosigmoid (eRS) approach and a lateral trajectory through the glossopharyngo-cochlear triangle as the surgical corridor for these cases. METHODS: High-riding PICA aneurysms treated by microsurgery were retrospectively reviewed, comparing exposure through the eRS and FL approaches. Clinical, surgical, and outcome measures were evaluated. Distances from the aneurysm neck to the internal auditory canal (IAC), jugular foramen, and foramen magnum were measured. RESULTS: Six patients with PICA aneurysms underwent clipping using the eRS approach; 5 had high-riding PICA aneurysms based on measurements from preoperative computed tomography angiography (CTA). Mean distances of the aneurysm neck above the foramen magnum, below the IAC, and above the jugular foramen were 27.0 mm, 3.7 mm, and 8.2 mm, respectively. Distances were all significantly lower versus the comparison group of 9 patients with normal or low-riding PICA aneurysms treated using an FL approach (P <. 01). All 6 aneurysms treated using eRS were completely occluded without operative complications. CONCLUSION: The eRS approach is an important alternative to the FL approach for high-riding PICA aneurysms, identified as having necks more than 23 mm above the foramen magnum on CTA. The glossopharyngo-cochlear triangle is another important anatomic triangle that facilitates microsurgical dissection.
Publication Date
3-1-2021
Publication Title
Operative Neurosurgery
ISSN
23324252
E-ISSN
23324260
Volume
20
Issue
3
First Page
252
Last Page
259
PubMed ID
33372992
Digital Object Identifier (DOI)
10.1093/ons/opaa362
Recommended Citation
Baranoski, Jacob F.; Koester, Stefan W.; Przybylowski, Colin J.; Zhao, Xiaochun; Catapano, Joshua S.; Gandhi, Sirin; Tayebi Meybodi, Ali; Cole, Tyler S.; Lee, Jonathan; Frisoli, Fabio A.; Lawton, Michael T.; and Mascitelli, Justin R., "The Glossopharyngo-Cochlear Triangle-Part II: Case Series Highlighting the Clinical Application to High-Riding Posterior Inferior Cerebellar Artery Aneurysms Exposed through the Extended Retrosigmoid Approach" (2021). Neurosurgery. 1402.
https://scholar.barrowneuro.org/neurosurgery/1402