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Purpose: Descemet's membrane detachment (DMD) is a rare but potentially serious complication of cataract surgery. Although there are no consensual guidelines regarding the diagnosis or treatment of DMD, incorrect treatment may result in irreversible corneal changes with visual sequellae. The purpose of our study is to describe the diagnosis and treatment of DMD., Methods: We report a series of 9 cases of DMD, their diagnosis, treatment and outcomes. We tested the HELP protocol retrospectively against our 9 real-life cases., Results: Two cases recovered with simple medical management, 4 required air-bubble descemetopexy, and three required keratoplasty. Our study revealed that the main factor associated with poor outcomes is late diagnosis and management., Conclusion: Our series illustrates the importance of proactive management and timely diagnosis by performing anterior segment OCT in the setting of persistent postoperative corneal edema., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Introduction: Descemet's membrane endothelial keratoplasty (DMEK) can replace just the corneal endothelium and respect the natural corneal anatomy. Currently, the technique of endothelial graft preparation remains manual and non-standardized., Purpose: To report anatomic and functional results after DMEK, and compare two techniques of graft preparation., Methods: Single-center retrospective study, including 64 eyes of 64 patients undergoing DMEK, from September 2014 to February 2016 at Clermont-Ferrand University Medical Center. The "classic" preparation was used in 44 patients (group 1) and the "variant" preparation was used in 20 patients (group 2). An analysis of functional parameters (visual acuity), anatomy (pachymetry, corneal edema, endothelial cell count) and keratometry (sphere, cylinder, mean keratometry) was performed during the first postoperative year., Results: The mean follow-up was 10.0±2.5 months. The average preparation time was 12.3±8.1minutes, with 14.4±8.8 in group 1 versus 7.8±3.0 in group 2 (P<0.001). At six months, the best corrected distance visual acuity was significantly better in group 1 with an acuity of 0.28±0.28 LogMAR in group 1 and 0.37±0.30 LogMAR in group 2 (P<0.01). The best corrected near visual acuity was also better in group 1 at 6 months, with an acuity of 0.29±0.24 LogMAR (P<0.001) in group 1 and 0.37±0.28 LogMAR in group 2 (P=0.02). Improvement in visual acuity was continuous for the 2 groups. At 6 months, endothelial cell loss was greater in group 1 than in group 2, but the difference was not significant (P=0.44). Central corneal thickness was similar between the 2 groups. Finally, no change in keratometry parameters was found between preoperative data and 6 months in each group or between the two groups., Conclusion: DMEK led to an improvement in all parameters as well as rapid visual rehabilitation. The new variation in preparation saved a considerable amount of time without decreasing graft survival or postoperative results., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Introduction: The endothelio-descemetic interface (EDI) of a deep anterior lamellar keratoplasty (DALK) may become the locus of a neovascular proliferation. Bevacizumab (Avastin) is an antiangiogenic alternative available for curative treatment in deep corneal neovascularization., Observation: We report the case of a 49-year-old woman who had received two arcuate relaxing incisions for high astigmatism after DALK. She developed graft rejection associated with significant neovascular stromal invasion in the EDI of the graft-host interface. Two subconjunctival injections of bevacizumab 1 month apart as well as thermocauterization of the feeding vessel were necessary and effective. No recurrence has been observed after 2 years of follow-up., Discussion: Corneal neovascularization can be a cause of DALK rejection. A combination of anti-antiangiogenic and physical methods may abort graft rejection and permanently restore graft function., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Unlabelled: Detachment of Descemet's membrane (DM) is a rare complication of cataract and glaucoma surgery. Although permanent corneal edema is the usual outcome of a large detachment, spontaneous clearing of the cornea may occur., Case Report: A 55-year-old man underwent trabeculectomy in 1991 under local anesthesia. One day later the cornea was edematous, with a large superior DM detachment curling inward in the anterior chamber, limited by a thin blood pigmented line. Two months after cornea had cleared, and remained clear for ten years, with 20/20 visual acuity and intraocular pressure of 14mmHg., Discussion: Small detachments of DM after surgery are not rare and usually reattach spontaneously. However, extensive detachment results in overlying corneal edema and may require surgical reapposition. In our case, the cornea cleared spontaneously in the absence of DM repositionning, as denuded corneal stroma may be covered by newly regenerated DM. Before any surgical repair of DM detachment, one should consider spontaneous clearing of the cornea as a possible outcome.

Optical, scanning and transmission electron microscopy examinations were performed in two cases of polymorphic posterior corneal dystrophy. The first case demonstrated typical clinical features, histologic examination revealing the presence of granular deposits in the posterior stroma, and an anarchic fibrillary zone between the stroma and Descemet's membrane. The latter was thickened, with a normal striated fetal zone, an intermediate zone composed of fibrils and long and short collagen fibers, and a normal adult zone. Cells lining the anterior chamber were of the typical endothelial type. Clinical signs in the second case were less evocative even though the father of the patient presented a typical form. Histology showed similar granular deposits in the posterior stroma, and the fibrillary zone beneath Descemet's membrane, which was thickened and delaminated and composed of three layers. Anterior chamber lining cells were disposed in several layers and had numerous surface microvillosities. They were linked by many desmosomes. These cells were therefore of the epithelial type. Comparing the findings in these two cases demonstrates that whereas many common signs existed there was a fundamental difference between the cell types on the posterior surface of the cornea. A review of all possible hypotheses led to the conclusion that the epithelial type cells are of mesenchymatous origin, similar to endothelial cells, as they possess the identical property of secreting a normal adult type of Descemet's membrane and of ensuring deturgescence of the corneal stroma. The pathological mechanisms involved, probably biochemical in nature, which provoke this anomaly can be fairly precisely determined as developing during fetal life, but they remain totally inexplicable. This hypothesis of a mesenchymatous cell developing into an epithelial type allows polymorphic posterior dystrophy to be regarded as a distinct entity, with similar features to other neonatal posterior dystrophies and a vast group of endothelial dystrophies including, among others, congenital edematous dystrophy.

Secondary alterations in Descemet's membrance were noted in corneal specimens from 20 patients undergoing transfixing keratoplasty, after examination by optical, and in some cases, by transmission or scanning electron microscopy. The most frequent anomaly, thickening of Descemet's membrance, was observed in cases of prolonged or recurrent corneal affections, particularly interstitial keratitis, advanced forms of keratoconus, cicatricial leukomas, and keratoconus. Thickening was due to juxtaposition, with a normal Descemet's membrance, of repair tissue made up of collagen interspersed with zones of cell necrosis and isolated fibrils. These different layers could be interpreted as successive deposits of reparative endothelial cells, the ultrastructural appearance of each layer being characteristic of the type of cell from which it was derived. In this way, the history of each cornea can be reconstituted, from the original normal endothelial cell to the final endothelial repair cells, passing through all the intermediary types of fibroblastic cells. This relationship between the cells which manufacture descemetic tissue and the structure of Descemet's membrance is particularly evident in Groenouw's macular dystrophy type II in which mucopolysaccarides are deposited. Descemetic verrucosities were observed in interstitial keratitis, of syphilitic origin or not, in one case of keratoconus, one case of buphthalmia, two cases of corneal leukoma, one case of vitreocorneal contact from aphakia, and in cases of Groenouw's type II dystrophy. The lesions are either isolated or spread across the posterior surface of the cornea. They differ from the verrucosities of primary cornea guttata by their irregular disposition, their frequent coalescence, the persistence of an endothelial regenerative process, their ultrastructural characteristics close to those of Hassal-Henlè's bodies, and more particularly by the association of a granular material with narrow and wide interval striated collagen. Various hypotheses are discussed which could provide an explanation why certain cells lay down Descemet's membrance in the form of tuberosities, and why these may present in alignments, but no satisfactory definite conclusion can be reached.

A case of bilateral corneal dystrophy in a young 6-year-old patient with an Ehlers-Danlos syndrome is presented. Thin opaque lamellae of different densities were observed in the posterior corneal stroma, and there were some subepithelial opacities. An irregularity of Descemet's membrane was also noted. The classification of this dystrophy is discussed, as well as the possible relation between the dystrophy and diseases of the elastic connective tissue.

The injection of alpha-chymotrypsin into the posterior chamber of the eye is known to produce an experimental ocular hypertension of long duration in animals. The present study reports the pathological changes which occur in the eye during the first nine months after the ocular injection of alpha-chymotrypsin in rabbits. Six weeks after treatment most of the eyes showed a buphthalmia and an intraocular pressure elevation which varied greatly from animal to animal. The anterior chamber angle of the treated eyes showed a progressive enlargement. Several days after the enzyme injection a transient increase in thickness of the cornea and Descemet membrane was noted. Cupping of the optic disc, characterized by a total disappearance of the optic nerve head fibers and an excavation beginning at margins of the retina appeared after four months and in most cases were present seven months after the treatment. More or less prominent retinal degeneration was also evidenced three months after enzyme injection. The results indicate alpha-chymotrypsin-induced occular hypertension in the rabbit leads after several months to pathological change in the eye analogous to that observed in human glaucoma.

We analysed the histological and ultrastructural aspects of corneal buttons obtained by keratoplasty in two patients presenting breaks in Descemet's membrane. The edges of the breaks appear clinically as glassy ridges or ledges and are also called Haab's lines. One patient had a birth trauma and the other had congenital glaucoma. The edges of the breaks coiled anteriorly towards the stroma and were dramatically thickened by a multilaminar Descemet's like membrane that exhibited excrescences within its outer part and that was secreted by regenerated endothelial cells. Only one case was analysed by SEM. Secondary guttuta could not be detected by this technique because it was completely covered by a sheet of newly secreted fibrous tissue that prevented the warts from indenting the endothelial cells. The part of cornea corresponding to the break was also covered by a new thick Descemet's like membrane exhibiting guttate warts. This study is thus a good opportunity to discuss the mechanisms of endothelial and Descemet's membrane regeneration.