engleski

The incidence of Blink-reflex abnormalities in patients suffering from the Idiopathic trigeminal neuralgia

We have done a study to determine the incidence of Blink-reflex abnormalities and EEG changes in patients suffering from the idiopathic trigeminal neuralgia. The study has been done on 25 subjects diagnosed according to the ICD-X criteria. The symptomatic disease had been ruled out by means of laboratory and radiologic tests. All patients have been newly diagnosed and received no therapy sofar. We have stimulated the supraorbital foramen and recorded the evoked response from both mm. orbicularis oculi. We have measured the amplitudes and the latencies of the ipsilateral early phasic component (R1) and the bilateral late tonic component (R2, R2� ). EEG was recorded using the cap electrodes and the International 10-20 EEG system. The results have been compared to those of the control group of age and sex matched healthy adults. In the group of subjects suffering from the idopathic trigeminal neuralgia, the Blink-reflex results showed slightly prolonged latencies of both R2 and R2� when stimulating the afflicted side and normal latencies of all components when stimulating the contralateral side, proving the dysfunction in the afferent part of the reflex cycle. No significant differences of amplitudes have been noted. The latencies of late components have exceded the normal range (+2.5 SD) in 35% of the cases. EEG changes, mostly diffuse or bitemporal appearance of theta waves, have been found in 27% of the subjects tested. EEG findings and Blink-reflex late components latencies showed a high level of correlation with each other and with the frequency of symptoms. We believe that Blink-reflex changes are more frequently encountered among patients with idiopathic trigeminal neuralgia than EEG abnormalities, and that combining the two tests can improve the clinician� s insight in patients� s actual state.

blink reflex; trigeminal neuralgia

nije evidentirano