Spectrum of Visual Impairment in Cerebral Venous Thrombosis: Importance of Tailoring Therapies Based on Pathophysiology.

Abstract

Visual impairment can complicate cerebral venous thrombosis (CVT). Here, we describe the various pathophysiological mechanisms and treatments available. A retrospective chart review of all patients treated for CVT in a large quaternary teaching hospital was done, and cases with visual impairment due to CVT were identified. The various mechanisms causing visual impairment in CVT were (1) raised intracranial pressure (ICP) caused by venous thrombosis without venous infarcts resulting in a benign intracranial hypertension-like presentation of CVT, (2) venous infarcts involving the occipital cortex, (3) raised ICP following the development of a secondary dural arteriovenous (AV) fistula, and (4) arterial occipital infarcts due to posterior cerebral artery compression secondary to herniation in large venous infarcts. Apart from using systemic anticoagulants to attempt recanalization and drugs with carbonic anhydrase inhibitor activity to reduce the ICPs, treatment modalities employed to save vision were (1) recanalization by local thrombolysis, stenting, or mechanical devices; (2) cerebrospinal fluid diversion procedures such as theco-periotoneal shunting; (3) optic nerve sheath fenestration; and (4) specific treatment for conditions such as dural AV fistula occurring as a late complication. CVT can cause visual impairment through different pathophysiological mechanisms. Depending on the mechanism, treatment strategies need to be tailored. Furthermore, very close monitoring is needed both in the acute and in the follow-up period, as new pathophysiological mechanisms can arise, compromising the vision. This may require a different treatment approach. Literature on this aspect of CVT is lacking.