Optical coherence tomography confirms shunt malfunction and recurrence of raised intracranial pressure in optic atrophy.

BACKGROUND Investigating potential cerebrospinal fluid (CSF) shunt malfunction can be a challenge. Optical coherence tomography (OCT), a non-invasive imaging technique, is used to monitor changes at the optic nerve head in papilloedema. Conventional teaching suggests that in the presence of optic atrophy the optic nerve head may not re-swell in response to a relapse in raised intracranial pressure (ICP). METHODS A retrospective case series of three patients who had prior CSF diversion surgery for idiopathic intracranial cranial hypertension (IIH) is presented demonstrating the benefit of non-invasive OCT imaging confirming raised ICP. RESULTS Recurrence of raised ICP, due to malfunctioning CSF shunt, was diagnosed in three patients requiring further surgical intervention. All re-presented acutely with headache and visual disturbances. All had a prior diagnosis of optic atrophy. In all patients, OCT peripapillary retinal nerve fibre layer qualitative image analysis and quantified progression analysis permitted easy detection of the recurrence of papilloedema. CONCLUSION OCT imaging supports clinical decision making in shunt malfunction, even in the presence of established optic atrophy secondary to IIH