Bilateral abducens nerve palsy associated with subarachnoid hemorrhage

Isolated abducens nerve palsies associated with intracranial aneurysms have rarely been reported. The purpose of the study was to study the patients with bilateral abducens nerve palsy in association with subarachnoid hemorrhage (SAH).

All patients admitted and managed at our center with a diagnosis of SAH and had bilateral abducens nerve palsy were included in the study. The demographic and clinical details, radiological findings, treatment data, and outcome of these patients were retrieved from the computerized database of our hospital.

Nine patients, with a mean age of 49.4 years, met the inclusion criteria. Male to female ratio of 1.25:1). Average duration of symptoms before presentation was 2.6 days (ranging from 1 to 4 days). Third nerve palsy in addition to bilateral abducens nerve palsy was present in 4 patients (44%). DSA demonstrated aneurysms in 7 patients; 4 had posterior circulation aneurysms and 3 had aneurysms of anterior circulation. Two patients had angionegative SAH. The abnormality resolved in all but one patient over a time period of 4-9 weeks, and one patient died due to unrelated cause.

Bilateral abducens nerve palsy in association with SAH is rarely described. Proposed mechanisms include direct compression of the bilateral abducens nerves, vasospasm of the pontine branches of the basilar artery and hydrocephalous. Most of the patients in our series showed resolution of the symptoms over a period of 4-9 weeks.