The interesting paper by Nubile and associates demonstrates the utility of confocal microscopy in evaluating limbal stem cell deficiency and the palisades of Vogt. Their technique involves a water immersion objective lens coupled to the cornea with a polyacrylic gel and topical anesthesia. The authors state that “low patient compliance and eye movements could preclude the correct visualization of the desired corneal and limbal structures … acquisitions are relatively time-consuming and required skilled examiners for a complete examination of the total corneal surface and all limbal structures.” In this regard it is worth noting that the limbal palisades of Vogt and the interdigitating rete ridges of epithelial cells are rather easily and quickly photographed via routine noncontact slit-lamp photography with or without fluorescein angiography. The high quality of such simply acquired photographs permits quantification of the number, type, dimensions, and location of the rete ridges.
The authors also state that “palisades of Vogt … were considered present when revealed in at least three limbal quadrants examined, [and] partially present [my emphasis] if revealed in only one or two sectors….” Interestingly, normal individuals often show quadrantic predilections for presence or absence of the palisades and the rete ridges; specifically, the inferior quadrant typically has more palisades and rete ridges than does the superior quadrant, and the temporal and nasal quadrants may have no visible palisades or rete ridges at all in some normal subjects. Their presence, therefore, in fewer than three quadrants (ie, “partial presence”) in an individual patient should not necessarily be construed as evidence of corneal or of conjunctival disease.