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Purpose: This paper reviews surgical modalities for treatment of keratoconus at the threshold of the 20th century., Methods: All ophthalmic literature from 1895 until 1925 in English and German, available at the library of the Institute of Ophthalmology, London, United Kingdom, was studied with respect to this topic., Results: Three thermal procedures were described; galvanocauterization with perforation, without perforation, and a non-contact application of heat to the corneal apex. Radial extension of a thermal burn to correct the minus cylinder represented a further modification. Excision of the conical area was suggested either as a lamellar dissection or as a full thickness trephination. Incision of the cone appeared to be less popular. In staged procedures, a combination of galvanocauterization, splitting of the cornea, conjunctival flap, and a subsequent optical iridectomy were applied., Conclusion: The treatment of keratoconus 100 years ago used refractive surgery to improve visual function by modifying corneal shape.

Purpose: Allopurinol shows beneficial effects in the systemic treatment of lens-induced uveitis. This is believed to be due to the reduction of oxidative tissue damage via a dose-dependent free radical scavenging ability and an immunomodulating effect. The purpose of this study was to investigate the immunological effects in experimental autoimmune uveitis after systemic treatment with allopurinol (AL) and steroids (STER)., Methods: 31 male Lewis rats were immunized with crude retinal extract, Freund's Adjuvans and pertussis toxin. The rats were divided into four groups: healthy rats (BASIS, n = 3), experimental autoimmune-uveitis without therapy (EAU, n = 9), 50 mg/kg bw. allopurinol i.v. (ALSYS, n = 9), and 7.5 mg/kg bw. methylprednisolone i.v. (STSYS, n = 10). ALSYS and STSYS received five intravenous injections during the 2 weeks immunization period. The rats' sera were tested against Western Blots (WB) of electrophoretic separations of retinal proteins. Based on digital image analysis, an analysis of discriminance was performed., Results: The multivariate analysis of discriminance revealed a significance difference between the WBs of ALSYS and STSYS (p < 0.01) compared to EAU without therapy. The number and intensity of peaks in WBs were strongly reduced in the ALSYS group compared to EAU., Conclusion: AL revealed a strong immunomodulating effect in the treatment of experimental autoimmune uveitis that is markedly stronger than that of steroids. Together with the antioxidative effect of allopurinol known from previous studies, this drug could be a new promising therapeutic approach in the treatment of uveitis.

Purpose: The aim of this study was to evaluate the immunomodulating activity of allopurinol using a model of lens-induced uveitis (LIU) and to compare these effects to those of steroids., Methods: We tested the sera of both LIU and control rats against western blots (WB) of SDS-PAGE separations of protein fractions from normal and LIU rat lenses. These blots were scanned using digital image analysis. A newly developed technique was used to compare the complex autoantibody (AAB) repertoires. Five groups of LIU rats were investigated: no treatment; single doses of methylprednisolone (MPR; 7.5 mg/kg body wt.i.v.); allopurinol (AL; 50 mg/kg body wt. i.v.); a combination of both drugs (AL and MPR); repeated application of AL (ALFR; 50 mg/kg body wt.i.v. every 2 weeks during the immunization period and a daily dose of approx. 25 mg/kg body wt. orally)., Results: Immunization induced complex antibody repertoires against lens proteins. Antibody repertoires of LIU rats were identical, regardless of whether the proteins were obtained from control, uveitis eyes, or corresponding healthy eyes of the same individual. AL showed a dose-dependent immunological effect in LIU treatment. Given as a single dose, AL revealed no significant change in the AAB repertoire; however, ALFR showed very clear modification of the AAB repertoires compared to both controls and rats receiving steroids., Conclusions: These results suggest dose-dependent effects of allopurinol in LIU treatment. Repeated application during the immunization period induced a strong immunomodulating effect of AL that was not observed after single doses.

A 54-year-old woman was referred for evaluation of an orbital tumour after 5 months of non-specific ophthalmic symptoms. Tissue obtained by an open orbital biopsy was highly suspicious for asymptomatic metastatic breast carcinoma, which was discovered a few weeks later. Unlike the primary tumour, which was an invasive lobular breast carcinoma, the metastatic tissue was repeatedly negative for oestrogen and progesterone receptor markers. A possible reason is a change in cellular cytoplasmic and nuclear protein composition during the metastatic process. Since the primary tumour was positive for the hormone receptors, the patient was treated by chemotherapy and tamoxifen. The follow-up supports a favourable effect of adjuvant endocrinological therapy even in cases with receptor-negative metastatic tissue. This report is in partial contradiction to some previously published cases and emphasises the role of receptor status in the primary tumour.

Desposition of immunoglobulins in the cornea occasionally occurs in benign and malignant lymphoproliferative conditions. A 52-year-old woman with recently discovered monoclonal gammopathy of undetermined significance (MGUS) was referred to our hospital. Slit-lamp and ultrasound biomicroscopy revealed bilateral deposits within all corneal layers. The precipitates were organized in a circle, leaving a perilimbal zone and the axial cornea clear. Light microscopy of a biopsy disclosed confluent subepithelial deposits and defects in Bowman's layer. Immunoperoxidase reaction was positive only for IgG and IgG-kappa. Transmission electron microscopy confirmed the presence of extracellular rectangular and arcuate immunoglobulin crystalloids with a 10-nm periodicity but a non-crystalline defraction pattern. A review of the literature showed that the circumferential pattern of immunoglobulin deposition is associated with short-term visual symptoms and good visual acuity. The present report supports a hypothesis of immunoglobulin deposition via the limbal arcade and contradicts the "tear theory."

Background: Severe complications such as a traumatic wound dehiscence have been described very rarely after radial keratotomy. The following case demonstrates for the first time that wound healing is not completed even 31/2 years postoperatively and that therefore an ocular blunt trauma may still cause a dehiscence of the radial incisions., Case Report: A 22-year-old patient presented in July 1993 to our emergency unit because of a corneal perforation in his right eye after a blunt trauma. His past medical history was significant for radial keratotomy surgery performed in January 1990 to correct a bilateral low-degree myopia (OD = -3.25 D; OS = -3.75 D). At surgery a horizontal rupture running through the entire cornea and including the two radial keratotomies at the 3 and 9 o'clock position was evident. The whole iris and lens were missing. The retina was completely detached. The corneal laceration was sutured. Twelve days later the retina was reattached with an encircling band, vitrectomy, endolaser and cryocoagulation, as well as silicone oil fill. Finally, a penetrating keratoplasty was performed 6 months after the accident. Thereafter, visual acuity improved to 0.1. The histologic examination of the corneal button showed that the wound healing of the incisions that had remained intact was not completed yet. Epithelial plugs of various size were still filling the somewhat dehiscent wound margins. Fibroblastic activity was detected in the surrounding stroma., Conclusion: Even several years after surgery, blunt traumas represent a definite risk for eyes undergoing radial keratotomy.

Posterior polymorphous corneal dystrophy (PPD) is a rare bilateral, autosomal-dominant disease. The presence of the epitheliumlike endothelium and the thickening of Descemet's membrane by the posterior collagenous layer (PCL) has been reported in the majority of published cases. Reepithelialization of the posterior cornea in donor tissue has been reported only once. Therefore, to examine this process we examined, by light and electron microscopy, three corneal buttons (an original and two subsequent keratoplasties after 3 and 4 years, respectively) from the left eye of a patient with bilateral disease. Our study showed a repopulation of the posterior surface of the donor corneas by the host epitheliumlike endothelium, which was of identical morphology in each case. In contrast to the previously published work, a posterior collagenous layer in the failed grafts was absent from the axial cornea, where the epitheliumlike endothelium was in direct contact with donor Descemet's membrane. A PCL at the periphery in the failed transplants was of the fibrocellular type and differed from the fibrillar PCL in the first keratoplasty specimen. The fibroblastlike cells within the fibrocellular PCL were distinct from the underlying epithelial-like cells and contained numerous tertiary phagolysosomes. We suggest that the major contributor to the fibrocellular PCL in the repeat keratoplasties was a fibrous ingrowth from the host/graft junction and not the epitheliumlike endothelium. It appears that the synthetic capacity of the epitheliumlike endothelium was similar to that of the normal epithelium and was much lower than that of normal native endothelium.

A case of bilateral uveal melanoma in a 54-year-old man is described. On admission of the patient for a choroidal melanoma of the left eye, an asymptomatic ciliary-body tumour was detected in his right eye. A thorough general examination did not reveal any metastases. The left eye was enucleated and local excision of the tumour in the right eye was performed 2 months later. Histology confirmed the presence of malignant melanomas in both eyes. The tumours were of similar A/B spindle-cell type. The patient remained healthy, showing no sign of metastasis or local recurrence of melanoma 9 months after the date of diagnosis. The visual acuity in his remaining eye remained 6/6. Immunological assessment of the blood serum revealed abnormally high interleukin 1 beta (IL-1 beta) and IL-2 levels. Possible implications of these findings are discussed.

Background: Posterior polymorphous dystrophy of the cornea is an uncommon, but well-recognized, congenital disease affecting Descemet's membrane and endothelium. Visual impairment usually is minimal and slowly progressive. Edema develops in a small number of patients, necessitating a corneal graft in middle age. An early manifestation of posterior polymorphous dystrophy with corneal edema present at birth or soon thereafter is extremely rare; only a few ultrastructural reports are available., Methods: The corneal button of a 5-month-old baby with posterior polymorphous dystrophy was examined by conventional light and electron microscopy., Findings: The anterior banded zone of Descemet's membrane was thinned (2 microns) in the axial part of the cornea, contained defects in the paraxial part, and was absent at the periphery. Where present, the anterior banded zone was lined posteriorly by a fibrocellular layer (containing fibroblast-like spindle cells and striated collagen fibrils) and a fibrillar layer forming an abnormal posterior collagenous layer. This layer was lined posteriorly by degenerate overlapping endothelial cells, which also were in apposition to the stroma in regions with an absent anterior banded zone. The defects in Descemet's membrane were used by the abnormal keratocytes to migrate between the anterior banded zone and the posterior collagenous layer. At the periphery, a multilayer of spindle cells was present behind the stroma., Conclusions: Failure to produce a continuous anterior banded zone indicates an onset of the disease before the twelfth week of gestation. It appears that, in posterior polymorphous dystrophy, there is a mosaic of better preserved and dystrophic endothelial cells and that the presence or absence of the normal components of Descemet's membrane is determined by the proportion of dystrophic cells in the endothelial cell population.

Two corneal buttons were obtained from a patient with congenital hereditary endothelial dystrophy (CHED) at the ages of 2.5 years (right eye) and 14 years (left eye) and were studied by light and electron microscopy including immunogold labelling for collagen types I-V and laminin. The posterior collagenous layer (PCL) of Descemet's membrane contained collagen types I, III-V, and laminin: the latter was also localised to fine-banded and granular material in the posterior non-banded zone (PNBZ). Comparison of the endothelium 2.5 years and 14 years revealed occasional dystrophic changes in the former and extensive dystrophic changes in the latter. The distribution of collagen types I, III and V within the PCL supports previous morphological observations of fibroblast-like change of the endothelium in CHED. Persisting endothelial properties were manifest as positive labelling of type IV collagen and laminin. An excessive amount of laminin found in PNBZ and PCL is another stress-related endothelial reaction.