Fig. 4.5 In vivo confocal microscopy (IVCM) images (400 × 400 mm, Heidelberg Retina Tomograph Ð Rostock Cornea Module (HRT-RCM)). Numerous microcysts within the epithelium in a functioning Þltering bleb (a). A dense connective tissue in a non-functioning bleb (b). Amiodarone corneal epithelium deposits (c). Crystal deposits in the corneal epithelium in the stroma in nephropathic cystinosis (d)

Limitations of IVCM

A high degree of compliance is needed to obtain high-resolution images and to carry out a dynamic examination. IVCM remains a contact diagnostic tool and in highly sensitive eyes, the IVCM analysis may cause ocular discomfort and thus increase eye movements that may blur the images.

IVCM, to be really useful, must be performed and interpreted by an experienced operator. As many structures are untypical, images should be interpreted carefully. Because IVCMÕs Þeld of view is small, the operator has to move the objective over the ocular surface tissues. Similarly, when IVCM is used to follow changes in repeated examinations, one of the major limitations is the difÞculty of imaging the same area over time.