Efficacy of Arachnoid-Plasty on Chronic Subdural Hematoma Following Surgical Clipping of Unruptured Intracranial Aneurysms.

BACKGROUND: We aimed to elucidate the effects of arachnoid plasty (ARP) on chronic subdural hematoma (CSDH) occurrence following clipping surgery.

METHODS: In total 217 patients (ARP, n = 97; non-ARP, n = 120) who had undergone unruptured intracranial aneurysm (UIA) surgical clipping via the pterional approach were retrospectively assessed. Predisposing factors for CSDH development following the surgery were investigated. Thickness and volume of the subdural fluid collection (SDFC) were measured to determine whether ARP affects postoperative SDFC.

RESULTS: The occurrence of postoperative CSDH was higher in patients without ARP compared to those with ARP (12.5 vs. 3.1%; P = 0.01). In multivariate analyses, having an SDFC volume ≥15 mL on postoperative day (POD) 8, (odds ratio [OR] = 15.113; range = 3.159-72.290), and male sex (OR = 4.274; range = 1.291-14.148) were identified as independent predictive factors. Having had ARP (OR = 0.228; range = 0.056-0.927) was, as an independent variable, negatively correlated with the occurrence of CSDH (P < 0.05). Moreover, SDFC volume ≥15 ml on POD 8 was significantly less common in the ARP group compared with the non-ARP group (P = 0.03).

CONCLUSION: Patients who underwent ARPs developed fewer CSDHs following UIA clipping surgery. The factors that predicted the development of CSDH included male sex, SDFC volume on POD 8, and ARP. In addition, the ARP patients had lower SDFC volumes (<15 mL). These findings suggested that ARP reduced the incidence of CSDHs after surgical clippings in patients with unruptured aneurysms.