An in depth analysis of histopathological characteristics found in keratoconus.

AIMS: The aims of this study were to re-assess the histopathology of the disease by introducing more modern measuring techniques and to determine if axial stromal thinning, which is the most apparent change, is related to the other alterations observed. METHODS: Recipient keratoconic corneas from 36 patients following corneal transplantation were studied. Haematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) staining were used to identify breaks in Bowman's layer and Descemet's membrane. Thickness of corneal layers was measured by Leica QWin software. Epithelial and stromal thickness were measured in each sample at the periphery of the corneal button and at the area of maximal stromal thinning. The presence of apoptotic cells in Bowman's layer breaks was detected by terminal deoxynucleotidyl transferase mediated dUTP-X nick end labelling. RESULTS: In all 36 corneal samples the central stroma, at the apex of the cone, was thinner than the peripheral. There was a negative correlation between central stromal and central epithelial thickness (p = 0.009). Bowman's layer breaks were found in 92% of corneas. Apoptotic cells were detected at the level of Bowman's breaks membrane. We found a positive correlation between epithelial thickness and the number of Bowman's layer breaks (p = 0.009 for central epithelial thickness and p = 0.003 for peripheral epithelial thickness). Descemet's membrane deformities were observed in 19% of corneas and central stromal thickness of these corneas was significantly less than corneas without breaks (p = 0.006). CONCLUSIONS: There are various different histopathological features associated with keratoconus and some of them are very subtle and not very well studied. Accurate measurements also suggest some correlations between them. Stromal thinning is associated with the number of breaks in Descemet's membrane, but it is the thickening of the epithelium which is associated with breaks in Bowman's layer.

Ocular adnexal diffuse large B-cell lymphoma: local disease correlates with better outcomes.

PURPOSE: To describe the clinical, immunohistochemical and prognostic features, as well as outcomes of a large series of patients with orbital and periorbital diffuse large B-cell lymphoma (DLBCL). DESIGN: This study is a multicentre, retrospective non-comparative consecutive case series. METHODS: The setting for this study was institutional. A total of 37 consecutive patients identified from the institutions' databases with periorbital and orbital DLBCL were enrolled in the study. A retrospective chart review was used for observation. The main outcome measures were patient demographics, clinical features, imaging, immunohistochemical and histopathological data, treatments administered, and survival. RESULTS: A total of 20 out of 37 cases (54.1%) represented localised periorbital disease (group L), 11 of 37 (29.7%) had systemic disease at presentation with periorbital disease (group S1), and 6 of 37 (16.2%) had previous history of systemic lymphoma (group S2). In all, 28 out of 30 (93.3%) patients were CD20+, 5 of 25 (20%) were CD3+, and 11 of 11 (100%) were CD79a+ (varying denominators reflect the different numbers of patients tested). A total of 25 out of 32 patients (78.1%) received chemotherapy, 14 (43.8%) received rituxmab plus chemotherapy, and 19 (59.3%) received radiotherapy. Nine deaths occurred, one in group L (not lymphoma related), six in group S1, and two in group S2. Five-year Kaplan-Meier survival estimates were 55.9% for all cases, 90.9% for group L, 36.0% for group S1, and 0% for group S2. One-year progression-free survival estimates in groups S1 and S2 combined were 58.3% for patients treated with rituximab and 28.6% for those who were not. CONCLUSIONS: To our knowledge, this report represents the largest series of patients with periorbital and orbital DLBCL in the literature. The difference in survival between groups L, S1 and S2 was striking, reflecting the grave prognosis of systemic DLBCL, but conversely the relatively optimistic outlook for patients with localised disease. Rituximab plus chemotherapy may be associated with increased survival.