[Usefulness of the blink reflex in a case of brainstem neuro-Behcet's disease]

Brainstem is the most frequently affected structure in neurobehçet disease. Brainstem auditory evoked responses (BAER) and magnetic resonance imaging (MRI) have been employed in early diagnosis of the disease. We present here a case of neurobehçet disease which brainstem lesion was suspected by blink reflex and corroborated by MRI. BAER were normal in this case.

The patient was a woman, 49 years old, diagnosed from Behçet's disease. Clinical symptoms consisted of dizziness, headache, nausea, vomiting and bilateral tinnitus preceded by fever in the previous days. Neurological examination showed increased tendon reflexes and adiadochokinesis. Cerebrospinal fluid was inflammatory but aseptic. Computerised tomography and BAER were normal. Blink reflex recording showed abnormalities after the stimulation of the right supraorbital nerve in R2 component, ipsilateral and contralateral, the remainder components being normal. This finding was compatible with a lesion in the spinal tract-nucleus of the right trigeminal nerve. Cranial MRI showed several areas of high signal intensity in protuberancial calotte and spinal tract-nucleus of the trigeminal nerve. The patient improved after prednisone and chlorambucil combined therapy. Serial blink reflex studies were normal, while the patient was asymptomatic.

These results indicate that determination of blink reflex together with BAER may be of help in the evaluation of a more extensive area of the brainstem in neurobehçet's disease, even in absence of trigemino-facial symptomatology. Early diagnosis is important because of neurobehçet's morbi-mortality.