Reductions in bilateral transverse sinus pressure gradients with unilateral transverse venous sinus stenting for idiopathic intracranial hypertension

Background Venous sinus stenting is an effective treatment for papilledema associated with idiopathic intracranial hypertension (IIH). It is unclear whether unilateral transverse-sigmoid sinus (TSS) stenting adequately decompresses the contralateral TSS system in cases of bilateral transverse sinus stenosis. The objective of this study was to compare changes in bilateral TSS pressure gradients following unilateral TSS stenting in a series of patients with IIH. Methods Consecutive patients from a single institution who underwent venous sinus stenting for IIH with measurement of bilateral pressure gradients before and after stenting for IIH were enrolled. Pressure gradients in both TSS pre- and post-stenting were measured during the procedure. The TSS with the highest gradient was stented. Changes in TSS pressure gradients following stent placement were calculated for both TSS. Mean changes in pressure gradients of ipsilateral and contralateral TSS were calculated. Results Sixteen patients with IIH who underwent TSS stenting were included. All were female. Mean age was 36.4 years. The right-sided TSS was the stented side in 12 (75.0%) patients. The mean pre-stent pressure gradient of the ipsilateral TSS was 19.3 mmHg (SD=10.8), which was reduced to a mean of 3.8 mmHg (3.4) following stent placement (P =<0.0001). On the contralateral (non-stented) side, the mean pre-stent gradient of 15.1 mmHg (7.5) was reduced to a mean of 7.8 mmHg (6.6) following stenting (P=0.006). Conclusions The use of a single stent provides some venous decompression of the contralateral non-stented stenosis in most cases of IIH treated with endovascular therapy.