Trigeminal Hyperexcitability in Idiopathic Intracranial Hypertension: A Blink Reflex Study

Investigating the Blink Reflex Abnormality in Dry Eye Patients

Introduction Dry eye is an ocular surface disorder caused by increased evaporation, decreased tear production, or mixed form. Tears are secreted by the lacrimal gland after lacrimal nerve stimulation connected to the facial nerve. In nerve damage, tear secretion decreases, and dry eye develops. Our aim is to investigate the presence of pathology in the facial trigeminal nerve and neuronal pathways that provide reflex connections between these nerves by measuring the blink reflex in patients with dry eyes. Methods Schirmer test and tear breakup time were performed. Tear breakup time measurement was repeated three times, and the average of three was accepted. Tear breakup time <10 seconds and Schirmer test <10 mm without local anesthesia were accepted as dry eye. Patients having traumatic corneal pathology, ectatic corneal disease, inflammatory and microbial keratitis, previous ocular surgery, glaucoma, diabetic retinopathy, and chronic neurological diseases were excluded. The control group was randomly formed from 42 eyes of 21 healthy volunteers. Blink reflex was measured in both groups, and the R1 and R2 responses of the two groups were compared. Written consent was obtained from the patient (or legal guardian) so that her medical data could be published. Results There was no significant difference between the two groups in R1 and R2 responses in both eyes. There was no significant difference in terms of gender between the two groups (p=0.100). The mean age in the patient group was significantly higher than in the control group (p<0.000). The mean Schirmer test in the patient group was 8.6±1.1 mm in the right eye and 8.97±1.0 mm in the left eye. Conclusion There was no central pathology observed in terms of reflex blinking in dry eye disease. However, in future studies, brainstem fiesta sequence magnetic resonance imaging (MRI) can be planned to evaluate central pathologies in more detail.