Clinical course of idiopathic intracranial hypertension with transverse sinus stenosis

Abstract

Objective: Transverse sinus stenosis (TSS) is common in idiopathic intracranial hypertension (IIH), but its effect on the course and outcome of IIH is unknown. We evaluated differences in TSS characteristics between patients with IIH with "good" vs "poor" clinical courses.Methods: All patients with IIH seen in our institution after September 2009 who underwent a high-quality standardized brain magnetic resonance venogram (MRV) were included. Patients were categorized as having a good or poor clinical course based on medical record review. The location and percent of each TSS were determined for each patient, and were correlated to the clinical outcome. Results:We included 51 patients. Forty-six patients had bilateral TSS. The median average percent stenosis was 56%. Seventy-one percent of patients had stenoses .50%. Thirty-five of the 51 patients (69%) had no final visual field loss. Eight patients (16%) had a clinical course classified as poor. There was no difference in the average percent stenosis between those with good clinical courses vs those with poor courses (62% vs 56%, p 5 0.44). There was no difference in the percent stenosis based on the visual field grade (p 5 0.38). CSF opening pressure was not associated with either location or degree of TSS. Conclusion: TSS is common, if not universal, among patients with IIH, and is almost always bilateral.There is no correlation between the degree of TSS and the clinical course, including visual field loss, among patients with IIH, suggesting that clinical features, not the degree of TSS, should be used to determine management in IIH. Idiopathic intracranial hypertension (IIH) is a syndrome of isolated elevated intracranial pressure (ICP) of unknown etiology, responsible for visual loss from papilledema in about 25% of cases.

Headache prevalence and clinical features in patients with idiopathic intracranial hypertension (IIH)

“…In fact, clear data on this topic are not available as only recently some reports have focused on the evaluation of the possible correlations between some clinical and instrumental aspects in the follow up of IIH patients [8][9][10][11].…”

Idiopathic Intracranial Hypertension: Diagnosis and Therapeutic Approach

“…The main neuroimaging findings that may accompany IIH are empty sella (70%), distention (45%), and tortuosity (40%) of the perioptic subarachnoid space, flattening of the posterior sclera (80%), protrusion of optic nerve papillae into vitreous, and transverse sinus stenosis (90%) (Figure 2, 3) (4,7,30,33,34). It should not be forgotten that these findings are not specific to IIH and other pathologies that may cause these findings must 45 be evaluated.…”

“…Anatomic studies have shown that stenosis is due to trabeculae, septa or hypertrophic granulomas (38). The presence of transverse sinus stenosis following normalization of CSF pressure in patients with IIH (39), and the absence of correlation between visual field loss and the degree of stenosis (34) suggest that stenosis is a result rather than an etiologic factor.…”

“…Transverse venous sinus stenting is another defined invasive procedure in IIH, but it is questionable as to whether the stenosis is a cause or a result (34). Therefore, the contributions of restoring venous sinus flow with this invasive method are controversial.…”

An update on the pathophysiology of idiopathic intracranial hypertension alias pseudotumor cerebri

“…However there is current evidence that some patients with IIH have bilateral transverse sinus stenosis (BTSS). [70] The transverse sinuses are well-known to be asymmetric in most individuals and an unilateral hypoplastic transverse sinus is considered a "normal variant" without any reported changes of ICP. MRV with an auto-triggered elliptic centric-ordered sequence demonstrated variable degrees of cerebral venous stenosis in most of the IIH cases compared with normal controls.…”