Researchers recently presented a clinical prediction score to determine whether acquired third nerve palsy patients require neuroimaging; the results were given at the annual ARVO meeting. The new model shows that patients who are between the ages of 15 and 50 or between 51 and 70 with previous head trauma, absence of stroke or poor pupillary reaction or older than age 70 with at least two of the three aforementioned risk factors should be considered for neuroimaging studies. Otherwise, they note patients can be closely observed to avoid unnecessary imaging.

The retrospective study evaluated 97 eyes of 96 patients with isolated third nerve palsy, 42.3% of which were caused by ischemia and 57.7% by non-ischemic etiologies, such as aneurysm, trauma, tumor, inflammation and others. The team collected demographic data and clinical presentations to help determine predictive factors in favor of brain imaging.

Of the total eyes, 84.5% underwent neuroimaging due to initially suspected non-ischemic causes, 43.9% of which revealed concordant diagnoses. The study authors found that potential clinical predictors to perform a neuroimaging study were age, history of head trauma, absence of stroke and poor pupillary response.