Comparison of Clinical and EMG Diagnosis of Involuntary Eyelid Closure

ABSTRACT

BACKGROUND: Blepharospasm and apraxia of lid opening (ALO) are nonparalytic causes of involuntary eyelid closure (IEC). Recently Aramideh (1994) divided the IEC into 5 groups by electromyography (EMG) study, and reported that each group had different responses to Botulinum A toxin treatment. Objective: We looked whether clinical observation can match the EMG, and possibly predict the response to Botulinum A toxiu treatment. Method: Based on EMG study of Aramideh (1994), clinically observable characteristics of each group were defined. One of the authors reviewed the videotapes of IEC and applied the above criteria to make the clinical diagnosis. Other author blinded to the clinical information performed 2 channel EMG of levator palpebrae superioris (LP) and orbicularis oculi (00) muscles, and made the EMG diagnosis. Clinical and EMG diagnoses were matched. Results: Twenty five patients (5 men and 20 women) were included in the study. Clinically, 16 were diagnosed as group I (blepharospasm), 1 as group 111(combined blepharospasm and LP motor impersistence), 7 as group tV(combined blepharospasm and involuntary LP inhibition), and 1 as group V(involuntary LP inhibition). There were no patient in group ll (combined dystonic activities of LP and 00). On EMG study, 14 were diagnosed as group 1, 2 as group ll, 1 as group 111, 7 as group IV, and 1 as group V The mismatch between the two diagnoseis occurred between group I and tV in 4 patients, group I and ll in 2, and group I and 111 in 2. Conclusions: Clinical observations are generally correct in predicting EMG diagnosis. Holvever groups with mixed features(ll, 111, and Iv) are difficult to diagnose by clinical observation only. Usefulness of clinical and EMG diagnosis on predicting Botulinum A toxin response will need to be evaluated. Key Words Involuntary eyelid closure, Blepharospasm, Apraxia of lid opening, Electromyography.