Stability of limbal stem cell deficiency after mechanical and thermal injuries in mice.

We studied the reproducibility and stability of limbal stem cell deficiency (LSCD) in mice following controlled injuries to the corneal and limbal epithelia. In one method, corneal and limbal epithelia were entirely removed with a 0.5 mm metal burr. In the other, limbus to limbus epithelial removal with the burr was followed by thermal injury to the limbus. These two methods were compared with a previously published one. Unwounded corneas were used as control. The corneas were examined monthly for three months by slit lamp with fluorescein staining. Immunofluorescence staining for cytokeratin 12 and 8 on corneal wholemount and cross sections were performed to determine the phenotype of the epithelium. Mechanical shaving of the epithelium, with or without thermal injury, resulted in a reproducible state of LSCD marked by superficial neovascularization, reduce of keratin 12 expression and presence of goblet cells on the cornea. The phenotype was stable in 100% of the eyes up to at least three months. Thermal injury produced a more severe phenotype with more significant stromal opacification. These corneal injury models may be useful for studying the mechanisms leading to limbal stem cell deficiency.

Confirmation of Choroidal Varix Through Divot Sign on Spectral-Domain Optical Coherence Tomography.

Enhanced depth imaging spectral-domain optical coherence tomography (EDI SD-OCT) provides a rapid and easily accessible measure to evaluate suspicious choroidal lesions. A 60-year-old woman was referred for evaluation of an inferotemporal slightly pigmented lesion that showed a large hyporeflective elevation in the deep choroid on EDI SD-OCT. After applying pressure to the globe, repeat EDI SD-OCT showed flattening of the lesion with a prominent depression or "divot" within the choroid of the center of the lesion. If noted on imaging, this divot sign is an additional reproducible diagnostic finding that can correctly identify a suspicious choroidal lesion as a benign choroidal varix.