ABSTRACT NUMBER: ESOC2026A2143 VENOUS SINUS STENOSIS IN IDIOPATHIC INTRACRANIAL HYPERTENSION: INTRACRANIAL COMPLIANCE AFTER BEST MEDICAL THERAPY VERSUS VENOUS SINUS STENTING

Abstract Background and aims Idiopathic intracranial hypertension (IIH) is increasingly recognized as a venous cerebrovascular disorder, frequently associated with transverse sinus stenosis (TSS). Venous sinus stenting (VSS) has been adopted in selected patients to restore venous outflow; however, its impact on intracranial physiological dynamics remains incompletely understood. Intracranial compliance (IC), reflecting the pressure–volume relationship of the intracranial compartment, may provide insight into cerebrovascular adaptation in venous outflow impairment. We aimed to compare non-invasive IC parameters in IIH patients with TSS treated with best medical therapy (BMT) versus VSS. Methods We conducted a single-center observational study including adults (≥18 years) with IIH and TSS between 2020 and 2022. Patients were managed with BMT or VSS according to clinical indication. IC was assessed using Brain4care®-derived intracranial pressure waveform metrics, including the P2/P1 ratio and time-to-peak (TTP), obtained in supine and seated positions. Continuous variables were expressed as mean ± SD or median (IQR). Statistical analyses were performed using R, with p<0.05 considered significant. Results Among 158 screened patients, 66 were included (49 medical therapy; 17 VSS). The VSS group was older, had lower body mass index, and, as mostly asymptomatic, required lower doses of acetazolamide and topiramate after intervention. No significant differences were observed between groups in P2/P1 ratio or TTP in either body position. Conclusions In IIH associated with TSS, non-invasive assessment revealed similar IC patterns after BMT and VSS. These findings suggest that IC may represent a stable physiological marker of venous cerebrovascular adaptation, complementing clinical outcomes in IIH management. Conflict of interest Lorena Souza Viana, Fabiano Moulin de Moraes, Sandro Luiz de Andrade Matas, Gisele Sampaio Silva: nothing to disclose.