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Purpose: Only epithelial cells are thought to express blood group antigens (bga) A and/or B in normal corneas, and ABO blood group (bg) matching seems to reduce immune rejection in high risk transplantations. This study attempts for the first time to investigate to what extent the bga A and/or B are expressed in diseased corneas., Methods: Thirty-nine diseased corneal buttons of 39 patients were examined. Immunohistochemical staining of paraffin-embedded sections was performed with monoclonal mouse anti human blood groups A and B antibodies using the Streptavidin-Biotin-peroxidase complex technique (LSAB Kit, Dako)., Results: The expression of blood group antigens A and/or B on the cornea was found to correlate directly with the blood group of the patients in all cases. The corneal epithelium of all 18 patients with blood groups A and/or B could be stained with antibodies to bga A and/or B. However, neither bga A nor bga B could be detected in any corneal cells of patients with the blood group O (21 patients). In addition to the epithelium, the stromal keratinocytes as well as the endothelium contained immunohistochemically detectable bga A and/or B in cases of keratitis or keratoconus, but not in stromal and/or endothelial cells of corneas with pseudophakic bullous keratopathy and Fuchs' dystrophy (all patients with the bgs A and/or B)., Conclusion: These findings show that an up-regulation of bga A and/or B in corneal stromal and endothelial cells is possible in diseased corneas. This phenomenon might play an important role in graft rejection after corneal transplantation.

Purpose: This study compares the influence of different corneal preservation media on HLA-DR positive corneal Langerhans cells (LCs)., Methods: Using fluorescence-associated immunohistochemistry, corneal sections were stained for HLA-DR antigens after preserving corneal-scleral discs in three different storage media: organ culture medium. Optisol and McCarey-Kaufman medium. HLA-DR positive LCs were present in corneal epithelium and upper stroma of fresh corneas., Results: A storage period of even 3 days had a significant influence on the number of HLA-DR positive corneal LCs. The number of LCs decreased at the limbus from 15.3 +/- 4.1 LCs/ 0.25 mm2 to 11.8 +/- 1.2 LCs/0.25 mm2 (p < 0.01) during preservation in McCarey-Kaufman medium, to 11.2 +/- 1.9 LCs/0.25 mm2 (p < 0.01) during preservation in organ culture medium and to 12.7 +/- 3.4 LCs/0.25 mm2 (p < 0.01) during preservation in Optisol. A greater loss was detected after 7 days and we found a cell number of 1.6 +/- 1.1 LCs/0.25 mm2 (p < 0.001) after storage in organ culture medium and of 1.4 +/- 1.5 LCs/0.25 mm2 (p < 0.001) after storage in Optisol. The donor tissues entirely lacked HLA-DR positive LCs, regardless of the preservation medium used, when stored for up to 14 days., Conclusion: These results demonstrate that loss of HLA-DR antigens is mainly related to storage period and is independent of the type of preservation medium and preservation temperature.

Background: Corneal HLA-DR antigens are going to be lost during organ culture storage. This study investigated if this phenomenon is based on down-regulation of the HLA-DR antigen, or on a loss of the HLA-DR-positive corneal Langerhans cells (LCs)., Material and Methods: Corneal LCs were stained in situ by the method of fluorescence-associated immunohistochemistry, and the organ culture mediums underwent flow cytometric analysis for HLA-DR-positive corneal LC at the end of the storage period., Results: All stored corneas were negative for HLA-DR after 14 days and HLA-DR antigens could be detected in culture medium at the end of the storage time., Conclusion: Flow cytometry showed that organ culture storage leads to loss of HLA-DR-positive cells and not only to a loss of antigen presentation.

Background: Organ culture medium and Optisol are the most commonly used corneal storage mediums. This study compares the costs for these two methods., Methods: In the calculation of costs we did not just take the direct costs into account, but also tried to determine the fixed costs per transplanted cornea with corresponding assumptions., Results: Proceeding on the assumption that 50 stored corneas were transplanted per year, an amount of 11,660 ATS (1,666 DM, 857 ECU) for each organ cultured and 11,986 ATS (1,712 DM, 881 ECU) for each graft preserved in Optisol was calculated. Raising the number of transplanted corneas to 400 per year, each tissue stored in organ culture medium costs 2,811 ATS (402 DM, 207 ECU) and those preserved in Optisol 3234 ATS (462 DM, 238 ECU)., Conclusion: Since organ culture storage gives us a reduction in costs of more than 15% compared to storing in Optisol, when preserving 400 transplantable grafts, from the business economics aspect, this storage method should be preferred.

Background: HLA-DR antigen plays a key role in transplantation immunology. Organ culture storage leads to loss of HLA-DR-positive corneal Langerhans cells. This study investigates the importance of prolonged storage period for the success rate after penetrating keratoplasty., Patients and Material: Eighty-four patients with 99 penetrating corneal transplantations were examined retrospectively. Group 1 represented keratoplasty patients with an average corneal storage period of 1.9 days (+/- 1.4) and in group 2 the patients received tissues stored for 9.8 days (+/- 4.7)., Results: The success rate of high-risk patients was 34.4% (+/- 8.7) in group 1 and 69.2% (+/- 12) in group 2 after 18 months (p < 0.01). In non-risk patients we had a success quota of 72.7% (+/- 8.2) in group 1 and 91% (+/- 6.1) in group 2 (p < 0.01)., Conclusion: We found significantly better results in patients receiving tissues stored for an average time of 9.8 days than in those receiving corneas preserved for 1.9 days. The results are thought to be based on the loss of HLA-DR-positive cells during prolonged organ culture preservation.

Purpose: The effect of retinal cryopexy on the vitreous was studied morphologically in an animal model., Methods: The retina and vitreous were frozen with single cryolesions on one eye and 24 contiguous cryolesions on the contralateral eye in 16 rabbits. The cryoprobe was applied to the sclera from 3 mm to 6 mm posterior to the limbus at -60 degrees C until ophthalmoscopically visible whitening occurred. Two animals were killed on the first day; the third day; after 1, 2, and 4 weeks; and after 2, 3, and 6 months after surgery. The eyes were enucleated and prepared by the celloidin embedding method. Each 200-microgram section was examined by light microscopy. Areas of the specimens were dissected and studied by scanning and transmission electron microscopy., Results: Single cryolesions did not have a significant generalized effect on the vitreous. Evidence of local collagen destruction and dispersion of cells was found near the area of cryoapplication. Contiguous cryoapplication led primarily to increased density in the vitreous and subretinal edema. The vitreoretinal border was invaded by mononuclear cells containing pigment granules. Thickened collagen fibers were attached to the coagulated retina in a perpendicular manner and traversed the whole vitreous body. After 4 weeks the increased vitreous density slowly diminished, and preretinal capillaries surrounded by vitreous collagen started to proliferate from the vitreoretinal interface. After 6 months central vitreous collagen fibers looked normal. In the area of cryoapplication, vitreoretinal membrane formation had occurred., Conclusion: Single cryolesions have no significant effect of the vitreous. Multiple cryolesions lead to neovascularization soon after the procedure (1 month) and membrane formation later (6 months after the procedure). This supports the concept that the extensive use of cryopexy in human retinal surgery could contribute to the development of proliferative vitreoretinopathy.

The course of zonular fibers in the area of pars plicata corporis ciliaris could be shown down to the pigmented epithelial layer and its basement membrane. S ingle fibrils enter in a connection with the plasma membrane in allinvestigated parts. Fibrils could be observed in the cytoplasm of the ora serrata. For the other areas (pars plicata corporis ciliaris, parsplana) this can be suggested too.

Three areas in which zonular fibers of Zinn enter were demonstrated with the aid of scanning electron microscopy. 1. The area, which applied to the edge of the lens. 2. The area of Pars plicata corporis ciliaris. 3. The area of Pars plana. The connection of zonuar fibers with limited membran of vitreous body was presented too.

Our of 688 eyes with perforating injuries in 16 cases (2.33%) which were operated on in the years 1973 to 1979, a serious intraocular infection occurred. In 8.94% of the cases in which there were foreign bodies, and in 0.88% of the remaining cases, without intraocular foreign bodies, infection also occurred, although antibiotics were administered prophylactically. With intensive combined antibiotic therapy, and by performing vitrectomy as early as possible it is sometimes possible to save the bulb, and in some cases useful residual function can be achieved. The success of early results of vitrectomy in endophthalmitis recorded in the literature to date could not be obtained as late results in our cases.

The skin of Helix pomatia was investigated by biochemical methods and electronmicroscope. Biochemical investigations showed that Helix pomatia collagen represents a methionine-lacking collagen resistant to CNBr-cleavage. Electron microscopic studies showed a cross striation pattern of 53--57 nm.

The penetration of gentamycin into aqueous humor after parenteral application (i. m., i. v., s. c.) of non-inflamed and inflamed human eyes was investigated. The dose of gentamycin was 80 mg i.m. and i. v. respectively. A doses of 40 mg gentamycin was used by s. c. injection. With Agar-diffusions test it could be demonstrated that the level of gentamycin was higher in inflamed than in non-inflamed eyes.

For the first time we present electron-microscopic results of an actinomycosis of the lacrimal canaliculus. The interior of the actinomycotic conglomerate showed no evidence of a cellular defence reaction but in the loosly woven outer network of hyphae we observed a massive granulocytic reaction. Also, after phagocytosis the structure of the actinomycotic micro-organisms within the granulocytes is not significantly damaged. Within the tissue of the lacrimal canaliculus adjacent to the actinomycotic conglomerate we observed an increased number of plasmacells but no pathogenic organisms.

Characteristically stained polyacrylamide gels can be obtained by disk-electrophoresis in acid medium of several tissues of the bovine eye. The technique permits to prove different types of collagen in the eye, and allows the differentiation and identification of the tissues. By these results the different tissues of the eye can be divided into three groups. 1. Tissues showing two alpha collagen components in polyacrylamide gel (cornea, sclera, iris, ciliary body, anterior lens capsule, and the pigmented epithelium of the retina). 2. Tissues possessing one alpha component only (zonula fiber and vitreous body). 3. Tissues which show neither the alpha nor the beta and gamma component of collagen (lens nucleous and retina without pigmented epithelium).

Bacterial flora were cultured from 20 metallic intraocular foreign bodies which were removed by magnetic extraction. Bacterial flora were domonstrated in 35%. Report on the microorganisms isolated, the size of the foreign bodies and the time between the penetration and the magnetic extraction operation in relation to the contamination.

Vitreous body fibrils and zonula fibers are analyzed by disc-electrophoresis. In both tissues the presence of collagen is established. The disc-electrophoresis patterns of vitreous body fibrils and zonula fibers show that a different type of collagen is present in each tissue. The absence of the alpha 2-chain indicates that the tissues investigated contain no type I collagen but types consisting of three identical alpha-chains.

Changes in gilded molybdenum-wire after implantation in the rabbit skin were investigated by a scanning electron microscope. The described changes are caused by electrolytical action of the tissue fluid. Calcium-molybdat was found between the gold and the molybdenum layer.

The PMN-Elastase concentration in tear fluid was determined in 87 persons without eye disease and compared with the PMN-elastase values of 28 patients with ulcus corneae. A significant increase in the PMN-elastase concentration was found in patients with ulcus corneae (means = 1196 micrograms/l) in comparison with the control group (means = 73 micrograms/l). The lapse control shows that the PMN-elastase values in the tear fluid of patients with ulcus corneae are elevated for a number of weeks, even though there are clinical signs of healing of the ulcer. The determination of PMN-elastase in tear fluid represents a new parameter indicating the real end of the inflammatory processes in the eye.

Some proteases, i.e. trypsin, alpha-chymotrypsin, thermolysin, proteinase K, alpha-amylase, collagenase, and papain were investigated on their effect on isolated zonular fibers. All these enzymes but collagenase were zonulolytic active. An attack on the ground substance of the fibers by substances solving glycosaminoglycans and proteoglycans (hyaluronidase, EDTA, guanidinium chloride, H2O2) showed an increased effect of the enzymes used. These results suggest that the interfibrillar matrix has a protective function on the zonular fibers.