Hydrocephalus Revealed by Relapsing Bilateral Fourth Cranial Nerve Palsy

Introduction: Uni- or bi-lateral fourth cranial nerve palsy due to hydrocephalus and/or after VPS placement is a very rare oculomotor manifestation. We report a case of relapsing bilateral fourth nerve palsies demonstrating recurring hydrocephalus. We reviewed the literature (table1) in order to inform the clinician about the clinical assessment, the past medical history and the radiological findings that prompt research for this peculiar entity and to avoid misdiagnoses like palsies of the sixth cranial nerve. Diagnosis, intervention and outcome: The patient presented with recurrence of diplopia in reading position, partially resolved after a second VPS placement. A diagnosis of bilateral fourth nerves palsies was done after complete neuro-ophthalmological evaluation. A close follow-up demonstrated fluctuating level of diplopia by changing VPS valve resistance. An optimal placement of the VPS offered reduction and stability of diplopia. A final strabismus surgery was necessary to obtain complete symptoms release.