Response to comments on: Clinical and biometric characteristics of pediatric eyes with nanophthalmos.

Dear Editor, We thank the authors for the valuable comments and for providing us an opportunity to clarify the diagnostic criteria of pediatric nanophthalmos.[1] The standard definition of nanophthalmos according to the available literature includes three criteria, namely, axial length less than 20.5 mm along with high hyperopia and increased retinochoroidal thickness (RCS) of more than 1.7 mm.[2] We followed the same diagnostic criteria for our study cohorts also.[3] We do agree with the authors that there are no clear diagnostic criteria for pediatric nanophthalmos and there may be an overlap of diagnosis with relative anterior microphthalmos (RAM), high hyperopia, and posterior microphthalmos if only axial length is taken as the diagnostic criterion.[4] In our tertiary eye care center, patients less than 16 years are routinely evaluated in the pediatric clinic. Hence, the age criteria of less than 16 years were mentioned in our study cohorts. We completely agree with the authors that each hospital has its own age limit for treating pediatric patients, which may range from 14–16 years. We mentioned the mean ± SD age in our paper as 8.95 ± 4.0 years (Nanophthalmos group) and 10.47 ± 3.0 years (Control group).[3] The subgroup analysis of less than 17 mm versus more than 17 mm was done mainly to understand the differences in ocular biometric parameters amongst the NO group children. Eyes with axial length (AxL) <17 mm had significantly higher spherical equivalent, lower anterior chamber depth (ACD), and greater lens axial length factor (LAF) contributing to angle closure disease.[3] The purpose of our study was mainly to sensitize the ophthalmologists, who encounter children with high hyperopia, to be vigilant about nanophthalmos and record the baseline ocular biometric factors such as AxL, ACD, lens thickness (LT), LAF, LT/ACD ratio, keratometry, and RCS thickness. Additionally, we have emphasized the need for serial biometric measurements to identify NO children at risk of developing angle closure disease and glaucoma.[3] Financial support and sponsorship Nil. Conflicts of interest Nil.