Causes
Ear infections, trauma, hypothyroidism, tumours, or idiopathic (with no identifiable cause, the most common).
Diagnosis
Neurological examination plus a search for the cause (otoscopy, blood tests and sometimes an MRI scan).
Treatment
Treating the cause if one is identified. Protecting the affected eye (artificial tears, preventing ulcers) is the priority. Many idiopathic cases improve partially or fully over time.
Prevention
Treat ear infections promptly.

