We appreciate the interest of Drs Zhang and Wang in our study and this opportunity to reply to them. We evaluated our data again to reply to their comments as accurately as possible.
First, we found only 3 patients in whom the suprachoroidal layer was identifiable on the enhanced depth images of spectral-domain optical coherence tomography. In addition, in all 3 patients, the suprachoroidal layer was evident in the extrafoveal area, but it was not identifiable in the subfoveal region.
Second, we used data at preoperative baseline to evaluate the effect of cataract surgery on the choroidal thickness. This study design is better to control many confounders that possibly influence the change in choroidal thickness after surgery. Besides, we cannot always predict all confounders. A randomized controlled trial with strict procedures and a large number of subjects is, of course, the best way, although it may not be realistic for the purpose of the study.
Third, as Drs Zhang and Wang indicated, it is true that drastic reduction in intraocular pressure (IOP) (ie, more than 10 mm Hg) changed the choroidal thickness. However, it has not been clear whether the smaller change in IOP after cataract surgery can affect the choroidal thickness. In the subjects included in our study, the mean (SD) change in IOP from baseline to 3 months postoperatively was only −0.59 (2.19) mm Hg. As for blood pressure, we do not consider the change in blood pressure of each subject during 6 months significant.
Recently, another group of researchers reported similar results, supporting our conclusion. In the future we need to address how long the increase in choroidal thickness remains after cataract surgery.