The effect of lamina terminalis fenestration on shunt-dependent hydrocephalus development in ruptured anterior circulation aneurysms

Objective: Hydrocephalus occurs in approximately 20-35% of aneurysmal subarachnoid hemorrhage. Shunt surgery is the most definitive treatment for hydrocephalus. We aimed to investigate the effect of lamina terminalis fenestration (LTF) on the development of shunt-dependent hydrocephalus by examining all risk factors that may cause shunt-dependent hydrocephalus and to predict the necessity of LTF in ruptured anterior circulation aneurysms with the obtained data. Materials and Methods: The study compares 48 patients who underwent Lamina Terminalis Fenestration during anterior circulation aneurysm surgery with 90 patients who did not undergo Lamina Terminalis Fenestration for the development of shunt-dependent hydrocephalus. The medical records, surgical notes, radiological images, and outpatient follow-up notes of all operated patients were retrospectively reviewed, and the data were analyzed using the Statistical Package For The Social Sciences (SPSS) program. Results: According to the analysis involving multiple variables, the risk of shunt placement increased 8 times in patients with a worse mFisher grade (95% CI: 1,005-65,139; p=0.050) and 6 times in those with External Ventricular Drainage (EVD) (95% CI: 1,972-16,999; p=0.001). When all patients were examined regardless of aneurysm location, Lamina Terminalis Fenestration did not show a significant impact on preventing Shunt-Dependent Hydrocephalus development (p>0.05). Conclusion: Due to the limited options for preventive treatments of shunt-dependent hydrocephalus, predicting and managing shunt-dependent hydrocephalus in subarachnoid hemorrhage treatment is crucial. In patients identified as high risk for shunt dependency, the threshold of factors identified for shunt insertion may be lowered. This will create the advantage of earlier discharge to rehabilitation and reduce inpatient length of stay. Keywords: Shunt-Dependent Hydrocephalus, Lamina Terminalis Fenestration, External Ventricular Drainage, mFisher Grade