Slit ventricles in idiopathic intracranial hypertension appear to expand after venous sinus stenting: a volumetric analysis
Vishnu Achyuth Suresh, Siddharth Srinivasan, Patrick J Opperman, Sara E Wattier, Daniel L Surdell, William E Thorell, Mithun Sattur, Nicholas BorgBackground
Venous congestion is associated with tissue swelling in multiple organ systems. In idiopathic intracranial hypertension (IIH), its effects on brain parenchyma are less well defined, but may contribute to slit ventricles through increased parenchymal volume. We therefore analyzed ventricular volumes before and after venous sinus stenting (VSS).
Methods
Semi-automated ventricular segmentation was performed using 3D Slicer (image analysis and scientific visualization software) on pre- and post-VSS volumetric MRI or CT scans from patients with IIH at a single center (2022–2025). The primary objective was to quantify change in total ventricular volume. Secondary objectives were to assess compartmental changes, predictors of ventricular volume change, and associations between volumetric data and clinical outcomes.
Results
25 patients were included. Median time to post-stent imaging was 6.7 months (IQR 4.7–7.0). Median total ventricular volume increased from 10.96 mL (IQR 8.91–19.21) to 12.8 mL (IQR 9.72–20.32) (+16.8%, P=0.024), driven predominantly by increased lateral ventricular volume (+12.3%, P=0.021). Third and fourth ventricular volumes did not change significantly. No predictors of volume change were identified. Lower baseline ventricular volume was associated with higher odds of a favorable clinical outcome following VSS (OR 1.14, 95% CI 1.01 to 1.32, P=0.047).
Conclusion
There is a small but consistent increase in ventricular volume following VSS, driven by expansion of the lateral ventricles. Greater benefit from stenting was observed in patients with lower baseline ventricular volumes. These findings suggest cerebral venous congestion may contribute to slit ventricles in IIH, and that improved venous drainage may permit re-expansion of cerebrospinal fluid spaces.