Case of the Week
Section Editors: Matylda Machnowska1 and Anvita Pauranik2
1University of Toronto, Toronto, Ontario, Canada
2BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
Sign up to receive an email alert when a new Case of the Week is posted.
February 18, 2021
Drug-Induced Intracranial Hypertension
- Background:
- Drug-induced intracranial hypertension is a condition characterized by increased intracranial pressure presenting as an adverse drug reaction.
- Drugs most commonly associated with intracranial hypertension include vitamin A (at doses >25,000 IU daily) and related compounds (such as isotretinoin and all-trans retinoic acid), tetracycline-class antibiotics, recombinant growth hormone, and lithium.
- Clinical Presentation:
- Signs of increased intracranial pressure, including persistent headache, visual disturbances, and pulse-synchronous tinnitus, after initiation of therapy with vitamin A derivatives or other suspected drugs
- Key Diagnostic Features:
-
Prominent subarachnoid spaces around the optic nerves, flattening of the posterior sclera, intraocular protrusion of the optic nerve, optic nerve tortuosity, partially empty sella turcica, bilateral transverse sinus stenosis
-
- Differential Diagnoses:
- Idiopathic intracranial hypertension: Identical imaging appearances without exposure to predisposing therapeutics
- Venous sinus thrombosis: Unenhanced CT demonstrates hyperdensity of the involved sinus; sinus filling defect after contrast administration
- Hypoplastic dural venous sinuses: Usually unilateral, with consensual reduction of the size of the jugular foramen
- Extracranial venous outflow obstruction: Demonstrated by neck CT or MRI
- Medical conditions associated with intracranial hypertension: Identical imaging findings in the context of Addison disease and sleep apnea, among others
- Arteriovenous fistula: Typical findings include abnormally enlarged vessels in the subarachnoid space and enlarged transosseous vessels
- Decreased CSF absorption from prior infectious meningitis: Previous leptomeningeal enhancement and increased FLAIR signal in the CSF spaces
- Subarachnoid hemorrhage: Associated with superficial hemosiderin deposition demonstrated by gradient-echo and SWI sequences
- Treatment:
- Discontinuation of the inciting drug, therapeutic lumbar puncture, and acetazolamide therapy
Current Issue
Case Collections
