Correlation between lumbar puncture opening pressure and venous sinus pressure gradient in idiopathic intracranial hypertension (IIH)

Background: Venous hypertension has become a recognized condition associated with idiopathic intracranial hypertension (IIH). Thresholds for dural venous sinus stenting (VSS) remain a topic of debate. Methods: In 50 IIH patients, the lumbar puncture opening pressure (LPOP) and the pressure gradient across the dominant venous sinus were correlated. Clinical variables were compared; linear regression models were created. Venous stenting was performed in select patients with bilateral venous sinus stenosis, papilledema, LPOP >25 cmH2O, and a venous pressure gradient >10 mmHg. Results: Twenty-nine patients were selected for venous sinus stenting (VSS); 21 patients did not meet the criteria for stenting despite some IIH symptoms. After stent implantation, patients experienced improvement in their symptoms. Across all 50 patients, there was a significant correlation between LPOP and the pressure gradient across the stenosis of the dominant venous sinus (r = 0.76, 95% confidence interval [0.53-1.00], P < .001). Conclusions: An increased venous pressure gradient across the dominant sigmoid/transverse junction was strongly associated with an increased lumbar puncture opening pressure in IIH patients. A gradient increase of 1 mmHg correlated with an increase of LPOP by 0.85 cmH2O. Patients with higher baseline venous pressure gradients may therefore benefit the most from venous stenting.