Clinical Manifestation of Ocular Motor Nerve Palsies in a Tertiary Eye Hospital of Kathmandu, Nepal

Abstract

Introduction: Ocular motor nerve palsies are one of the leading causes of ocular morbidity in the neuro-ophthalmology clinic. Objective: This study was aimed to determine the aetiology of ocular motor nerve palsies in a tertiary referral eye center of Nepal. Methods: This hospital based cross-sectional descriptive study was carried out over a period of one and a half years. All cases of ocular motor nerve palsies were evaluated and relevant laboratory investigations and imaging studies were done. Results: Ninety–one patients with ocular motor nerve palsies were examined, of which 53 (58%) were males and 38(42%) were females. The mean age was 39.4 years ±18.29 years. Majority of the cases (n=78, 86%) had unilateral involvement and the most common chief complaint was double vision (n=58, 63.7%). The sixth cranial nerve palsy was most commonly seen (n=49, 53.85%) followed by third nerve palsy (n=22, 24.18%). Fourth cranial nerve palsy and combined cranial nerve palsies accounted for 10.99% each (n=10). Aetiology of ocular motor nerve palsies could not be determined in 31.8% of the cases. Among the identifiable etiologies were vascular diseases (n=24, 26.3%), infections (n=14, 15.3%), trauma (n=14, 15.3%) and neoplasms (n=9, 9.8%). Imaging studies were done in 92 %(n=84) of cases. In cases of combined cranial nerve palsies, positive diagnostic findings were noted in 50% (n=5) of the cases with imaging studies. Conclusion: The sixth cranial nerve palsy was the most common ocular motor nerve palsy in our study. The most common identifiable aetiology was vascular diseases followed by trauma. Besides ophthalmic examination, neurological evaluation and imaging plays an important role in diagnosis.