Comment on: Choroidal thickness is affected by smoking and mydriatics.

Sir, We read the article “Choroidal thickness profile in healthy Indian children” by Chhablani et al. with a great interest.[1] The authors aimed to study choroidal thickness (CT) and it's profile based on location in healthy Indian children using enhanced depth spectral domain-optical coherence tomography (OCT) They concluded that their study provided a valid normative database of CT in healthy Indian children and this database could be useful for further studies evaluating choroidal changes in various chorioretinal disorders. We congratulate the authors for their lightening study. We would like to make some contributions and criticism about the study and report an error which should be made by mistake by authors. The authors reported that they excluded subjects with high refractive error criteria during the study to avoid pathological CT values affect the results.[1] However, there were more factor which could affect CT than they used. One of these factors is dynamic exercise, and this factor increases the CT.[2] Topical mydriatics and smoking are other two factors which were reported to decrease the CT.[3,4] It's reported that smoking rate is high in youngs (15–24 years) in India, especially in males.[5] However in this study, the authors did not report if the subjects were a smoker or not. Furthermore, the OCT measurements for CT were performed with dilated pupils. So, the mydriatics might be affected the results. Finally, we want to inform an error about the value of the mean subfoveal CT. It's reported as 312.1 ± 45.40 μm in abstract but as 311.2 ± 45.19 μm in results. We think that this was made by mistake by the authors. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.