Lamina Terminalis Fenestration: A Beneficial Approach to Reduce Shunt-dependent Hydrocephalus in Patients with Aneurysmal Subarachnoid Hemorrhage with a Review of Literature

Abstract

ABSTRACT Objective: Hydrocephalus requiring shunt placement (12%–20%) is a common complication after aneurysmal subarachnoid hemorrhage (aSAH). Various studies suggest that fenestration of lamina terminalis (LT) during microsurgery for aSAH may be associated with a reduced rate of shunt-dependent hydrocephalus. We report a prospective analysis correlating fenestration of the LT with decreased shunt-dependent hydrocephalus after aSAH managed by microsurgical repair. Methodology: A total of 106 patients over a period of 1.5 years with aSAH treated by microsurgical aneurysm repair along with fenestration of LT were analyzed. Patients were treated by same surgical team and those patients where surgical clipping of anterior circulation aneurysms with LT fenestration was performed were included in the study. We compared the rate of shunting in patients operated on by routinely fenestration of the LT with that in cases where LT fenestration was not carried out (taking literature as control). This study design isolates the effect of fenestration of the LT on the incidence of shunt-dependent hydrocephalus. Results: There has been significantly lower rate of shunting (2.3%) in the patients where LT fenestration was done, versus 12%–20% in the cases where it was not preformed (P < 0.05). Furthermore, post-aSAH, hydrocephalus is associated with a higher grade of Fischer’s scale (Grade III and IV). Conclusion: Fenestration of the LT appears to be associated with a decreased incidence of shunt-dependent hydrocephalus of more than 80% after aSAH. This straightforward microsurgical maneuver should be performed whenever possible during aneurysm surgery.