Introduction Over the past several years, stenting of the transverse sinus has been gaining popularity as a treatment modality of idiopathic intracranial hypertension when there is evidence of venous sinus stenosis. The aim of this study was to better understand the role that stenting plays on the influence of the intracranial vascular blood flow and fluid dynamic changes.

Methods A retrospective analysis was performed on a prospectively maintained database of 20 patients who underwent 21 transverse sinus stenting procedures for the treatment of idiopathic intracranial hypertension, from January, 2012 to December, 2014. All patients had confirmed increased intracranial pressure and an increased pressure gradient > 8 cm H₂0 across the transverse or sigmoid sinus prior to stenting. We measured three pre- and post-stenting variables using digital subtraction angiography: 1) the intracranial arterial-venous transit time (AVTT), measured from the first appearance of contrast in the cavernous internal carotid artery to the jugular bulb, 2) washout times of four intracranial veins (vein of Labbé, vein of Trollard, superficial middle cerebral vein [SMCV], superior ophthalmic vein [SOV]) following an arterial injection, and 3) washout times of the transverse sinus following a superior sagittal sinus injection.

Results A total of 20 patients (21 stenting procedures), consisting of 19 females (95%) and 1 male (5%), were included in this study. The mean age at presentation was 38 years (range, 16–39 years). The pre- and post-stenting mean AVTTs were 6.36 ± 1.14 s and 4.74 ± 1.10 s respectively (∆ Mean = 1.62 sec [95% CI 0.92–2.32 sec], p < 0.001). There was a significant post-stenting decrease in the venous washout times (after arterial injection) of both the vein of Trollard (∆ Mean = 1.00 sec [95% CI: 0.18 – 1.82 sec], p = 0.018) and the SMCV (∆ Mean = 1.68 sec [95% CI: 0.66 – 2.69 sec], p = 0.002). There was also a significant post-stenting decrease in the venous washout time (after venous injection) of the transverse sinus (∆ Mean = 0.75 sec [95% CI: 0.28 – 1.22 sec], p = 0.003) There was no significant difference in the pre- and post-stenting washout times of the remaining veins. Interestingly, we also observed that the laterality of the transverse sinus drainage changed from bilateral transverse sinus drainage in 18 cases (86%) pre-stenting to bilateral drainage in only 12 cases (57%) post-stenting.

Conclusions Stenting of a stenosed transverse sinus in patients with idiopathic intracranial hypertension significantly reduces the intracranial arterial-venous blood transit time and venous-phase transit times of the veins of Trollard and SMCV. While arteriovenous transit time is variable, these findings are consistent with a significant hemodynamic alteration following venous sinus stenting.

Disclosures M. Crimmins: None. D. Kimball: None. S. Boddu: None. M. Dinkin: None. A. Patsalides: None.