Contralateral approaches to bilateral cerebral aneurysms: a microsurgical anatomical study

Abstract

<jats:p>In patients with bilateral supratentorial aneurysms, surgical clipping of all aneurysms via a unilateral approach would obviate the need for a second operation. The authors conducted a microsurgical study in human cadaver heads to examine the contralateral exposure for four common aneurysm sites in the anterior circulation: the ophthalmic artery (OA) origin, the posterior communicating artery (PCoA) origin, the internal carotid artery (ICA) termination, and the middle cerebral artery (MCA) bifurcation. Frontotemporal craniotomies were performed in 16 cadavers to evaluate the corridor for exposure of these sites from the contralateral side. Morphometric data, including lengths and diameters of major arterial segments and optic nerves, were documented for anatomical correlation.</jats:p> <jats:p>In this study, the contralateral OA origin was successfully exposed in 62% of specimens, the PCoA origin in 50%, the ICA bifurcation in 100%, and the MCA bifurcation in 62%. Exposure of the OA origin and, in some cases, the PCoA, required incision of the falciform ligament and mobilization of the contralateral optic nerve. Exposure of the MCA bifurcation was dependent on the length of the M<jats:sub>1</jats:sub> segment, with successful exposure only when this segment was shorter than 14 mm. Implications for the contralateral approach to aneurysms at these sites are discussed and the microsurgical corridors for exposure are described.</jats:p> <jats:p>For correlation with the anatomical study, a brief clinical review of patients with bilateral supratentorial aneurysms treated at The Johns Hopkins Hospital between 1992 and 1995 is presented. Guidelines for the contralateral approach to aneurysms are discussed with reference to the anatomical study and the clinical review.</jats:p>

Progression of an arterial infundibulum to aneurysm: case report

“…This technique, however, is not recommended for all the patients. The individual anatomy and clinical setting are the factors that have a major influence on the sucess 12 . In our case the unilateral approach gave us an unexpected advantage, as say, not only the possibility of clipping all aneurysms through the same operative approach, but above all, the opportunity of inspecting the origin of the right PcomA and being able to confirm the progression of IF to aneurysm, co-validating, thus, this report.…”

Craniotomy for Treatment of Unruptured Aneurysms Is Not Associated With Long-Term Cognitive Dysfunction

“…Of the 51 patients, 49 underwent frontosphenotemporal (pterional) craniotomies, 2 underwent combined frontosphenotemporal/subtemporal craniotomies for basilar artery apex aneurysms, and 4 underwent contralateral approaches 21 through frontosphenotemporal craniotomies for repair of bilateral supratentorial aneurysms. The surgical approach involved a curvilinear frontotemporal incision, subfascial dissection of the temporalis muscle, burr hole craniotomy with the Gigli saw, curvilinear dural opening, brain protection with Telfa and Bicol strips, and reversal of mechanical vasospasm with topical papaverine as previously described.…”

Surgical treatment of multiple intracranial aneurysms

“…Both groups were separated by the boundary of contralateral middle cerebral artery bifurcation. Although a number of reports are available on occlusion of bilateral aneurysms in the middle cerebral artery bifurcation along the unilateral approach (10,13), according to Oshiro's study (14), contralateral middle cerebral artery bifurcation is difficult to observe along the unilateral pterional approach when the contralateral M1 segment is >14 mm. Considering the surgical safety, aneurysms in the contralateral middle cerebral artery bifurcation were included in the third group.…”