Dear Editor,
We would like to thank the authors for their interest in our article titled “Evaluation of ganglion cell complex and retinal nerve fiber layer thinning in epilepsy patients.”[1] We wanted to clarify the questions they mentioned. Vitamin (folate and B12) values of the patients included in the study were checked. Those who were within normal limits were included in the study. Neurologic examinations of the participants were performed. Those with any neurologic disease (including migraine) were excluded from the study. Smoking history of the participants was not questioned. This may be considered a limitation of our study. However, the effect of smoking on the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) is controversial. Although there are studies showing thinning,[2,3] there are studies showing no change.[4,5] Some studies have also shown that smoking affects one but not the other.[6]
It is statistical that GCC is not significant in the inferior 3 mm. Measurements of the patient group (116.74 ± 13.47) and the control group (121.74 ± 8.90) revealed that the standard deviation was higher in the patient group. This difference seems to have affected the significance.
As our study was not suitable for drug evaluation in terms of number of patients and methodology, we grouped the patients as monotherapy and polytherapy recipients and compared them. We wrote in the limitations section that long-term and large-participant studies are needed to evaluate the effects of drugs and epilepsy on the retina.
Financial support and sponsorship: Nil.
Conflicts of interest: There are no conflicts of interest.
References
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