Fifty shades of gradients: does the pressure gradient in venous sinus stenting for idiopathic intracranial hypertension matter? A systematic review

Abstract

OBJECTIVE The role of venous sinus stenting (VSS) for idiopathic intracranial hypertension (IIH) is not well understood. The aim of this systematic review is to attempt to identify subsets of patients with IIH who will benefit from VSS based on the pressure gradients of their venous sinus stenosis. METHODS MEDLINE/PubMed was searched for studies reporting venous pressure gradients across the stenotic segment of the venous sinus, pre- and post-stent pressure gradients, and clinical outcomes after VSS. Findings are reported according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. RESULTS From 32 eligible studies, a total of 186 patients were included in the analysis. Patients who had favorable outcomes had higher mean pressure gradients (22.8 ± 11.5 mm Hg vs 17.4 ± 8.0 mm Hg, p = 0.033) and higher changes in pressure gradients after stent placement (19.4 ± 10.0 mm Hg vs 12.0 ± 6.0 mm Hg, p = 0.006) compared with those with unfavorable outcomes. The post-stent pressure gradients between the 2 groups were not significantly different (2.8 ± 4.0 mm Hg vs 2.7 ± 2.0 mm Hg, p = 0.934). In a multivariate stepwise logistic regression controlling for age, sex, body mass index, CSF opening pressure, pre-stent pressure gradient, and post-stent pressure gradient, the change in pressure gradient with stent placement was found to be an independent predictor of favorable outcome (p = 0.028). Using a pressure gradient of 21 as a cutoff, 81/86 (94.2%) of patients with a gradient > 21 achieved favorable outcomes, compared with 82/100 (82.0%) of patients with a gradient ≤ 21 (p = 0.022). CONCLUSIONS There appears to be a relationship between the pressure gradient of venous sinus stenosis and the success of VSS in IIH. A randomized controlled trial would help elucidate this relationship and potentially guide patient selection.

Men Are from Mars, Idiopathic Intracranial Hypertension Is from Venous: The Role of Venous Sinus Stenosis and Stenting in Idiopathic Intracranial Hypertension

“…McDougall and colleagues set out to answer this question by reviewing a total of 186 patients from 32 studies who underwent stenting and comparing their prestent TSG with clinical and visual outcomes. 66 They found that those with "favorable" outcomes had a higher mean prestent TSG of 22.8 mm Hg (vs. 17.4 mm Hg in those with unfavorable results) and a higher change in the TSG of 19.4 mm Hg (vs. 12.0 mm Hg). In a multivariate analysis controlling for other factors, the change in TSG correlated with the outcome; 94.2% of those with a TSG greater than 21 had a favorable outcome compared with only 82% of patients with a TSG 21 mm Hg.…”

Major complications of dural venous sinus stenting for idiopathic intracranial hypertension: case series and management considerations

“…1 Venous sinus stenting (VSS) has emerged as a safe and effective treatment option for patients with refractory IIH with associated venous sinus stenosis. 2 3 Metaanalyses have suggested roughly 90% improvement in papilledema, 80% improvement in visual symptoms, and 80% improvement in headache, [4][5][6][7][8][9] with major complication rates ranging from 1-7%. [5][6][7][8][9][10] The literature offers limited guidelines or recommendations for patient selection or treatment for IIH.…”

Characteristics and Outcomes of the Idiopathic Intracranial Hypertension Treatment in Intrinsic and Extrinsic Stenosis: A Single-Center Experience in China

“…Meanwhile, there is no significant difference in the pre-operative pressure gradient between stenting and medical treatment groups in intrinsic type of stenosis. Previous studies have reported that those with favorable outcomes had a higher mean pre-stent trans-stenotic pressure gradient [ 7 , 32 ]. Our results confirmed this finding.…”