Aim: To determine the types, causes and relative frequencies of abnormal tonic eyelid position in patients seen at the eye clinic of the University of Benin Teaching Hospital.
Method: A review of the case files of all new patients presenting with abnormal tonic eyelid position was done. Data on age, gender, laterality, type and aetiology of abnormal tonic eyelid position was obtained.
Result: There were 109 patients with abnormalities of tonic eyelid position. These included 51 males with a male: female ratio of 1:1.1. The age range was from 6weeks to 87years; mean age 37.6years (SD ± 23.9). There was unilateral involvement in 88 (80.7%) cases. Abnormalities of tonic eyelid position were ptosis 77 (70.6%), lagophthalmos 22 (20.2%), facial spasm 7 (6.4%) and lid retraction 3 (2.8%). The most frequent cause of ptosis was oculomotor nerve palsy while blepharospasm was the most frequent cause of facial spasm. Seventh nerve palsy was the most frequent cause of lagophthalmos while the three cases of lid retraction were seen in patients with thyroid eye disease.
Conclusion: Neurological and other debilitating illnesses were common causes of abnormal tonic eyelid position. Examination of the eyelid for tonic position should not be overlooked during ophthalmic evaluation.