To investigate the clinical features and risk factors of ischemic third, fourth, sixth cranial nerve palsy.

Retrospectively, we reviewed the medical records of 46 eyes of 46 patients who were diagnosed with ischemic third, fourth, sixth nerve palsy alone such as age of onset, risk factors, recovery rate and recovery time.

The mean age of onset was 64.9 years. Of the 46 patients, 15 patients (32.6%) in third cranial nerve palsy group, 15 patients (32.6%) in fourth cranial nerve palsy group, 16 patients (34.8%) in sixth cranial nerve palsy group. The risk factor of hypertension in 30 patients (65.2%) was the most common than other risk factors such as diabetes, hyperlipidemia, elevated blood hematocrit, ischemic heart disease, left ventricular hypertrophy, smoking. The mean number of risk factors was 2.3 ± 0.5 in third cranial nerve palsy group, 1.6 ± 1.1 in sixth cranial nerve palsy group, 1.4 ± 1.1 in fourth cranial nerve palsy group. Of the 46 patients, 42 patients (91.3%) were recovered. There was no significant difference in recovery rate by cranial nerve palsy. Recovery time of intracranial abnormalities group (10.5 ± 2.9 weeks) in brain imaging study was late as compared with that of no intracranial abnormalities group (7.5 ± 5.1 weeks).

The overall recovery rate of isolated ischemic third, fourth, sixth cranial nerve was high. But if there are intracranial abnormalities in imaging study, it took a long time to recover. Also ischemic third cranial nerve palsy had multiple risk factors characteristically.