[Clinical value of blink reflex:analysis of 548 patients]

To evaluate the clinic value of blink reflex (BR).

BR test was conducted among 584 patients with facial spasm (161 cases), face or upper extremities numbness (120 cases), Bell's palsy (102 cases), trigeminal neuralgia (31 cases), ptosis (30 cases), multiple cranial palsy or brain stem lesion (28 cases), cerebral vascular disease (19 cases), lateral face atrophy (16 cases), Guillain-Barré syndrome (13 cases), connective tissue disease (12 cases), diabetic peripheral neuropathy (12 cases), head trauma (11 cases), definite or suspected multiple sclerosis (10 cases), Meige syndrome (9 cases), Parkinson's disease (5 cases), or motor neuron disease (5 cases).

279 out of the 584 patients (47.77%) showed abnormal BR results. By analyzing of waveform, latency period and difference of bilateral side of BR test, the different BR changes caused by either peripheral damage to trigeminal nerve and facial nerve or by brain stem damages were distinguished.

As one convenient test, BR helps locate the lesion of trigeminal nerve or facial nerve and has highly diagnostic value to the lesion of brain stem, even to the subclinical lesion at the early time of some disease without any symptoms. When the BR results are coordinated with those by brain stem auditory evoked potential, the abnormality of brain stem function can be found and located earlier in some situation that can result to brain stem damage such as MS and systematical disease. Coordination of BR with radionuclide study or single-fiber electromyography helps increase the differential diagnosis of spasm of eyelid and MG.