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We review the clinical, histopathological, and ultrastructural findings and DNA phenotyping of a patient with Avellino corneal dystrophy exacerbated by laser in situ keratomileusis. The findings are reported and interpreted in the context of a literature review. The case highlights the possible difficulty of recognizing subtle dystrophic findings, as well as the importance of avoiding refractive surgical intervention in patients with Avellino corneal dystrophy to avoid exacerbation of dystrophic deposits in the cornea and subsequent reduction in vision.

Purpose: To determine whether viscoelastic materials effectively protect the corneal endothelium from air bubbles. Setting: Department of Ophthalmology, Yonsei University College of Medicine, Seoul, Korea. Methods: Human eye-bank and rabbit eyes had a standardized phacoemulsification procedure with or without viscoelastic material (Healon® [sodium hyaluronate 1.0%], Healon GV® [sodium hyaluronate 1.4%], or Viscoat® [chondroitin sulfate 4.0%−sodium hyaluronate 3.0%]). The integrity of the endothelium was examined after the procedure with F-actin staining and scanning electron microscopy. Rabbit eyes with and without viscoelastic material (Healon or Viscoat) had a standardized irrigation/aspiration (I/A) procedure. The mucinous layer of the endothelium was examined after the procedure with transmission electron microscopy. Results: In the phacoemulsification experiment without viscoelastic material, with Healon, and with Healon GV, the endothelium of human and rabbit corneas had many areas of cell loss in a pattern consistent with air-bubble damage. With Viscoat, endothelial cells remained intact. In the I/A experiment, the mucinous layer of Viscoat-exposed rabbit endothelium appeared thinner. In the same experiments without viscoelastic material or with Healon, the mucinous layer of the endothelium appeared normal. Conclusions: Viscoat effectively protected the endothelium from air-bubble damage. Viscoat appears to protect the endothelium by acting as a physical barrier. Its adherence is probably related to the way it interacts with the mucinous layer of the endothelium.

We evaluated the efficacy of tissue plasminogen activator in treating experimental suprachoroidal hemorrhage. Suprachoroidal hemorrhage was created in 30 white rabbit eyes by implanting four pieces of small, exogenously formed blood coagula into the suprachoroidal space. Animals were randomized for treatment with a surgical sponge soaked in 25, 50, or 75 μg of tissue plasminogen activator (tPA) or balanced salt solution (BSS®) as a control. The time when initiation and completion of clot dissolution occurred was established, and histological examination was performed to assess damage. Clot dissolution started within 30 min in the 50- and 75-μg tPA group, whereas it took 2.75 days in the control group; complete dissolution of blood clots took 4.5 h in the 75-μg tPA group and 14 days in the control group. Histological examination revealed a minimal change in photoreceptors within 6 h after treatment with 75 μg tPA. Treatment of suprachoroidal hemorrhage with tPA seems to be effective, but further investigations for determining the effective and nontoxic dose are required.

There have been numerous types of animal models of choroidal neovascularization (CNV) and retinal neovascularization (RNV). Understanding the pathobiology of CNV and RNV is important when evaluating and utilizing these models. Both CNV and RNV are dynamic processes. A break or defect in Bruchs' membrane is necessary for CNV to develop. This may be induced with a laser, mechanically via surgery, or in the setting of transgenic mice. Some of the transgenic mouse models spontaneously develop RNV and/or retinal angiomatous proliferation (RAP)-like lesions. The pathogenesis of RNV is well-known and is generally related to ischemic retinopathy. Models of oxygen-induced retinopathy (OIR) closely resemble retinopathy of prematurity (ROP). The streptozotocin (STZ) rat model develops features similar to diabetic retinopathy. This review summarizes general categories and specific examples of animal models of CNV and RNV. There are no perfect models of CNV or RNV and individual investigators are encouraged to choose the model that best suits their needs.

We describe an unusual case of composite lymphoma (CL) in the orbit. The clinical history and biopsy specimen of an 82-year-old woman with a right orbital mass were evaluated. The orbital biopsy contained a dense lymphocytic infiltration and nodules of large lymphocyte that immunostained positive for CD20. Flow cytometric immunophenotyping showed two distinct populations of cells, confirming the diagnosis of a simultaneous follicular lymphoma (FL) and chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). The patient was treated with CD20 antibody (rituximab) and is in remission at 3 months follow-up.