Length of Transverse Sinus Reinforcement Predicts Symptom Improvement After Venous Sinus Stenting for Idiopathic Intracranial Hypertension.

BACKGROUND AND

OBJECTIVES

Chronically elevated venous sinus and intracranial cerebrospinal fluid (CSF) pressures in idiopathic intracranial hypertension (IIH) may weaken the dural walls covering these sinuses, increasing their compliance and susceptibility to compression by elevated CSF pressures. This may contribute to proximal or distal stent-adjacent stenosis after venous sinus stenting (VSS), explaining the persistent or recurrent IIH symptoms and elevated CSF pressures in some cohorts. We sought to assess whether increasing the length of transverse sinus (TS) reinforced by the stent (TS-Stented) improved IIH symptom resolution and durability.

METHODS

We retrospectively included adult IIH patients who underwent VSS. Prestenting TS length (TS-Prestent) was measured from the lateral superior sagittal sinus (SSS) margin to the end of the stenotic segment. Poststenting, the unstented segment between the torcula and distal stent tip was subtracted from TS-Prestent to derive TS-Stented. Bivariate logistic regression was used to identify predictors of headache, visual symptoms, tinnitus, and papilledema improvement.

RESULTS

A longer TS-Stented significantly predicted improvements in headaches (adjusted odds ratio [aOR]: 0.782 [95% CI: 0.617-0.99]; P = .041), visual symptoms (aOR: 0.581 [95% CI: 0.387-0.873]; P = .009), and tinnitus (aOR: 0.881 [95% CI: 0.781-0.993]; P = .039) and showed a trend toward significance for papilledema (aOR: 0.521 [95% CI: 0.27-1.005]; P = .052). Interestingly, a longer TS-Prestent was associated with worse visual (aOR: 1.543 [95% CI: 1.084-2.195]; P = .016) and papilledema (aOR: 1.621 [95% CI: 1.011-2.598]; P = .045) outcomes. Factors representing elevated central venous pressure (eCVP, ≥8 mm Hg) were associated with no change or worsening symptoms: (1) eCVP-like-physiology (internal jugular vein pressures ≥10.5 mm Hg): worse visual outcomes (aOR: 40.423 [95% CI: 3.636-449.433]; P = .003); (2)higher anterior one-third SSS venous pressures: worsening headache (aOR: 1.141 [95% CI: 1.002-1.300]; P = .047), visual symptoms (aOR: 1.099 [95% CI: 1.013-1.192]; P = .023), and papilledema (aOR: 1.099 [95% CI: 1.013-1.192]; P = .023); and (3)higher body mass index: worsening headache (aOR: 1.136 [95% CI: 1.014-1.272]; P = .028) and papilledema (aOR: 1.204 [95% CI: 1.01-1.435]; P = .038).

CONCLUSION

We identified multiple venous anatomic and hemodynamic factors affecting post-VSS outcomes and propose increased dural compliance as a key mechanism, framing VSS and maximizing TS-Stented as a key approach to structural reinforcement against recurrent or adjacent level collapse.