We appreciate the interest and comments expressed by Dr Goldberg concerning our article and for bringing this interesting point of limbal palisades of Vogt slit-lamp photography to the readers’ attention. As correctly pointed out, the patient’s compliance and the examiner’s skill level represent critical factors conditioning the quality of the limbal images throughout its entire extension, and thus play an important role in whether these images are suitable for diagnostic purposes. However, as shown in our paper, distinct and detailed in vivo microscopic representation of the limbal architecture, throughout its entire extension (ie, all quadrants, not only the inferior limbus), can be obtained in the majority of the examined patients, in both healthy and diseased eyes. We do agree that the limbal palisades of Vogt can be documented by slit-lamp photography, but it is worth noting that this method and laser scanning in vivo confocal microscopy represent distinct imaging systems that explore the cornea at different levels and at significantly different magnifications (macroscopic vs cellular). The pathologic characteristics observed in our study with confocal microscopy of the limbal region of eyes affected by limbal stem cell deficiency—such as loss of the normal epithelial mosaic, cystic, and pleomorphic epithelial changes, and subepithelial fibrosis—can be finely characterized only with the high magnification and contrast that laser scanning confocal microscopy provides.
With respect to the second observation raised by Dr Goldberg, we definitely agree with the fact that the presence of Vogt’s palisades may significantly vary among individuals and within the limbal circumference of the same eye. In fact, in agreement with the results showed by Patel and associates and Zheng and Xu, we found that normal limbal palisade structures could be only partially detected in the majority of patients in whom the diagnosis of limbal stem cell deficiency was excluded. Therefore, in conditions of normality, the microscopic evidence of palisades in the limbal quadrants can be partial. On the other hand, in all cases in which the diagnosis of total or partial limbal stem cell deficiency was confirmed, the architecture of the limbal microscopic structures, including the palisades of Vogt, was significantly altered.