Electrophysiological evaluation of blink reflex in leprotic patients

الملخص EN

Hypothesis : Neuritis in “Leprosy” is the most important subject.

Leprosy is a chronic granulomatous disease, caused by Mycobacterium lease, which affects principally the skin and peripheral nervous system affecting the trigeminal and facial nerves.

Objective : to detect asymptomatic sub clinical cranial nerves involvement in leprosy patients using blink reflex (BR) as electrophysiological method.

Methodology : we studied 15 normal participants, 9 female and 6 male their mean age was 40.5 ± 9.0 yrs (range 26 yrs to 55.2 yrs) ; and 20 patients with leprosy (13 Female and 7 Male).Their mean age was 41.9 ± 10.4 yrs (range 24 yrs to 60.1 yrs) ; The duration of the disease was 10.8 ± 2.3 yrs.

Blink reflex responses were recorded after unilateral electric stimulation of the supraorbital nerve for quantitative analysis evoked 3 responses, early ipsilateral phasic component (R1), late ipsilateral tonic component (R2i) and late contralateral tonic component (R2c).

The mean latencies of R1, R2i and R2c components of the 5 stimuli delivered at intervals of at least 30 s were measured.

The distal motor conduction of the ulnar and deep personal nerves latencies was measured.

Results : Significantly prolonged latencies were recorded of both the ipsilateral early phasic component (R1) and bilateral late tonic components (R2i and R2c) in patients with leprosy compared to normal controls p < 0.05.

The distal motor conduction latencies (DMCLs) measured from ulnar nerve and deep personal nerve were significantly prolonged in leprosy patients.

There was no significant correlation between prolonged latencies of BR and DMCL of ulnar nerve and deep personal nerve with disease duration.

Conclusion : BR is a non-invasive electrophysiological evaluation like complement of electrophysiological evaluation of peripheral nerves and can be used as a method to detect asymptomatic neuropathy of trigeminal and facial nerves and could be a valuable test to identify patients at high risk for symptomatic cranial neuropathy.