Dear Sir,We thank Drs. Sanghi and Dr. Gupta for their interest in our article. Their comments add important insights into the development of the disease process. Our study looked at the patients when they came for vitreoretinal surgery. Only five out of 16 had been lasered at our hospital. Eleven patients were referred by colleagues outside of our system. Unfortunately, more information about their status at presentation was not available at the time of this study. At present, a more robust system of sharing treatment and diagnosis timeline for such referred patients has been established. Out of the six from our center, three had aggressive posterior retinopathy of prematurity (APROP) and one had zone 1 disease. The argument of the Dr. Sanghi and his careful assessment of the pictures does make a case for APROP being an important determinant in progress in disease despite retinal laser in the absence of laser these patients would have rapidly deteriorated to stage 5 disease. Previous studies have also shown that APROP in heavier (≥1500 g birth weight) premature infants occurs mostly in posterior zone 2 with flat neovascularization and atypical features such as large vascular loops.[1] Notably, a lot of babies in our country presenting with ROP needing surgery are larger.[2] Hence, the location of proliferation should probably have naturally been less central than that observed in our study. Therefore, we feel convinced about the location of the neovascularization/ridge as described in our article. Notably, this always seems to take place at the junction of lasered and nonlasered area and interestingly not further proximal as suggested by Dr. Sanghi. So convincing was the location of the proliferation just posterior to the margin of the nonischemic lasered retina that we had considered, giving it the toponym of “Pune Paradox.”We, however, concede that multiple factors rightly mentioned in the communication could jointly be responsible for central traction.[3]The very nature of the disease and the referral pattern makes it difficult to have large cohorts. All patients at our center underwent RetCam imaging, but these were not available for those referred from elsewhere.The studied comments in the letter to editor can be starting point for a new study with a national registry of ROP surgery as very few centers offering it at present. The authors acknowledge that all the ROP publications of the PGI Chandigarh group were central to our basic understanding of ROP in the Indian context.
Financial support and sponsorship
This study was financially supported by a grant from Mr. Nitin Desai, Desai Brothers, Pune, India.