Corneal Degeneration Research Articles

Diseases of the Cornea

Dr Merrill Grayson's major interest in ophthalmology has been the cornea, and<i>Diseases of the Cornea</i>reflects his many years of experience in this field. His broad knowledge of corneal disease has enabled him to write a textbook that presents vast amounts of useful information in an organized and efficient fashion. The first half of the book is extremely well written and covers corneal anatomy, fundamentals of history taking, congenital anomalies, and the inflammatory conditions of the cornea, conjunctiva, and eyelid. The section on keratitis is particularly well written, with appropriate emphasis on the clinical, laboratory, and therapeutic aspects of corneal infections. In addition, the chapters on superior limbic keratitis and chlamydial and viral diseases are also highly informative. The tight organization and smooth flow of information are not maintained in the second half of the book. For example, in the chapter on corneal degenerations, little attention is given to

The Corneal Endothelium and the Spectrum of Essential Iris Atrophy

We found that the spectrum of essential iris atrophy (progressive essential iris atrophy, Chandler's syndrome, and the Cogan-Reese syndrome) began as a corneal endothelial degeneration, which, with ectopic endothelial membrane overgrowth over an open angle, followed by contraction of this membrane and further growth onto the iris, accounted for all aspects of the syndrome. The contractile membrane caused the synechiae, the glaucoma, the corectopia, the ectropion uveae, the occasional iris nodules, and the iris atrophy. Thus we found this disease to be primarily of the cornea, and only secondarily of the iris. The results of this study led us to propose a new designation for this spectrum: primary proliferative endothelial degeneration.

Pellucid Marginal Corneal Degeneration

Pellucid marginal degeneration of the cornea is a bilateral, clear, inferior, peripheral corneal-thinning disorder. Protrusion of the cornea occurs above a band of thinning, which is located 1 to 2 mm from the limbus and measures 1 to 2 mm in width. American ophthalmologists are generally not familiar with the condition because most of the literature concerning pellucid degeneration is European. Four cases are described. This condition is differentiated from other noninflammatory cornel-thinning disorders such as keratoconus, keratoglobus, keratotorus, and posterior keratoconus. It is also differentiated from peripheral corneal disorders associated with inflammation such as Terrien's peripheral corneal degeneration, Mooren's ulcers, and ulcers from connective tissue disease.

Peripheral Corneal Degeneration and Occlusive Vasculitis in Wegener's Granulomatosis

A 61-year-old white woman, who had progressive arthritis over a two-year period, developed bilateral peripheral corneal degeneration. The superior cornea thinned to a thickness of approximately two thirds of normal. She died suddenly in the hospital and a primary occlusive vasculitis of the anterior ciliary arteries within the superior rectus muscles was found. There was necrotizing arteritis in the lungs, kidneys, adrenal caps, spleen, fallopian tubes, and skeletal muscle. The observation of an occlusive vasculitis of the anterior ciliary arteries in this patient supports the belief that ischemia may play a major role in peripheral marginal degeneration of the cornea.

Histology of spheroidal degeneration of the cornea in Labrador.

Nine specimens of the corneas of patients from Labrador and Northern Newfoundland affected by spheroidal degeneration (climatic droplet keratopathy) have been examined microscopically. Histochemical stains confirmed studies of similar corneal degenerations from other geographical areas that the droplets contain a protein which does not have all the characteristic properties of elastic tissue. Staining compatible in some instances with fibrin and "fibrinoid" was found. By immunoperoxidase techniques the droplets were located in the zones of greatest concentration of various plasma constituents, especially albumin and immunoglobulins G and A. Reasons are given why the abnormal deposits are not thought to be derived directly from corneal collagen. It is suggested that some of the plasma proteins, which are known to be diffusing through the cornea from the limbal vessels under normal conditions are acted upon by the ultraviolet light reflected from the ice of Labrador and degraded so that they accumulate in the superficial stroma.

Periosteal Graft in Scleromalacia

A case of scleromalacia perforans in a 60-year-old white male without any associated systemic diseases is reported. The patient had central retinal artery occlusion and Mooren's type of peripheral corneal degeneration in this eye preceding the development of scleromalacia. Various modalities of treatment, both medical and surgical, have been described in the literature and among surgical procedures various tissues were used as graft material in the areas of scleral thinning. We chose periosteum as the graft material on the basis of our experience with it in cases of "through-and-through" keratoprosthesis and the result has been very encouraging. Though our experience is limited to only one case, we feel that periosteum as graft material has a place in cases of scleromalacia.

Clinical Conditions Affecting The Basement Membrane of The Corneal Epithelium

Since the introduction of the electron microscope, the structure of the basement membrane of the corneal epithelium has frequently been described. However, only recently has the significance of the basement membrane in various clinically important conditions and its role in providing a means of adhesion between the epithelial cells and the stroma been fully investigated and appreciated. In this study the appearance of the basement membrane as seen with the electron microscope is described in various conditions of the anterior human cornea, including recurrent epithelial erosion syndrome, persistent epithelial defects, bullous keratopathy, keratoconus and numberous corneal dystrophies and degenerations.

Penicillium viridicatum mycotoxicosis in the rat. I: Ocular lesions

Ocular lesions developed in most rats fed killed rice cultures or fungal mats of Penicillium viridicatum. Lesions began after 7–14 days of feeding of the fungal diet as a slight opacity of the cornea. The opacity increased in severity over the next few days and was followed by the development of hypopyon and corneal vascularization in the more severely affected eyes. The initial histological lesions were oedema of the corneal stroma and hydropic degeneration of the corneal epithelium. These lesions were followed by interstitial keratitis, iridocyclitis, hypopyon and corneal vascularization. Involvement of the posterior segment of the eye was rare. The ocular lesions were apparently due to some mycotoxin(s) entering the aqueous humour and did not seem to be related to the presence and extent of hepatic damage nor to lesions in the accessory lachrymal glands.

Corneal perforations in Sjögren syndrome.

The postmortem histopathologic findings in the eyes of a patient with sjogren syndrome whose course was followed up for 15 years demonstrate a similarity between the marginal corneal degeneration in this disease and that found in Terrien degeneration. Conventional histologic techniques did not reveal positive evidence of the definitive cause of the lesions we noted. However, no inflammatory infiltrate or residue suggestive of an immune response was observed, nor was there any evidence of old or recent vascular inflammation or obliteration. The appearance of cataractous changes in each lens within a month after application of biologic tissue adhesive to seal the corneal perforations led us to suspect that this material can produce undesirable side-effects.

Clinical findings, course, and progress of Bietti's corneal degeneration in the Dahlak islands.

Bartolucci (1933) and Zanettin (I937) reported the presence of an unusual corneal disease in Italian Somaliland and the Dahlak Islands respectively. Falcone (I 954) published an excellent detailed account based on a large sample collected over I5 years in Mogadiscio. Coinciding with his observations, Guerra in Asmara had recorded similar findings; he communicated them to Bietti in Rome, who visited Asmara and Massawa and, linking the Eritrean cases with those of de Gaspare in Saudi Arabia, carried out an intensive study of the condition (Bietti, Guerra, and de Gaspare, I955). The lesion has since been called Bietti's corneal dystrophy by Gandolfi (I962) in Libya, by Etzine and Kaufmann (I964) in the Southern Transvaal, by Fretillere, Vedy, and Chovet (I967) in French Somaliland, and by Freedman (I972) in South West Africa. Freedman (i 965) described a somewhat similar, if less severe, condition, named by him Labrador keratopathy, which will be discussed later, and Wyatt (197I) reported identical cases in the North-West Territories of Canada. In 197I, the Scientific Exploration Society invited the writer to lead a small British expedition to the Dahlak Islands to study this disease in depth in village communities (Rodger, 1972). The expedition was mounted at the request of the Ethiopian Government.

Congenital hereditary bilateral non-attachment of retina. A sibship of two.

A brother and sister, the only two children of non‐consanguineous parents, have bilateral microphthalmos, degenerative corneal opacities, shallow anterior chambers, and in the anterior vitreous white masses like cotton wool with some large blood vessels. Excision of the mass from the vitreous cavity of one eye showed surprisingly normally developed detached retina round a core of fibrous condensed vitreous. Otherwise the children are normal and have the normal male and female karyotype.A very similar sibship has been reported by Franceschetti (1956) ‐ a brother and sister, children of first cousins, being affected; the consanguinity of these parents supports our suggestion that a recessive inheritance explains the abnormalities in our cases. No evidence of heredity exists in the similar case described by Magnus (1927) or in the group of possibly similar cases of “retinal dysplasia” without systemic involvement described by Reese &amp; Straatsma (1958), but our cases may well belong to the same category; also, our cases may represent examples of an extreme form of “falciform retinal folds”.

Climatic droplet keratopathy. I. Clinical aspects.

Labrador keratopathy and Bietti's nodular dystrophy are acquired corneal degenerations affecting men who have spent their working lives outdoors; they are thought to be caused by climatic exposure. This report shows that such corneal disease occurs more frequently than has been suspected and suggests ultraviolet irradiation as a common etiogenic factor. Since the clinical appearances and pathologic changes in all cases are similar, differing only in degree of severity, it is suggested that these diseases be considered a single entity called climatic droplet keratopathy.

Proteinaceous corneal degeneration. A histochemical study.

Clinical and histochemical data are presented in the case of a young man who had bilateral oily globules that were centrally located in the superficial corneal stroma. There was no associated corneal disease; however, epithelial involvement was noted to occur after several years. The material may have been a mixture of compounds but was basically protein, which appeared to be a product of degenerating corneal stroma itself and not an epithelial product as had been suggested in the past.

Climatic changes in the eyes of Eskimos, Lapps and Cheremisses.

Chronic and acute climatic changes observed in the eyes of Eskimos and USSR Cheremisses are described. Chronic climatic lesions are more common in men than in women. Pterygium seems to be about equally common in Eskimos and Lapps. The occurrence of pinguecula was about the same in all three populations and much higher than in the urbanized Finns. Band‐shaped climatological corneal degenerations seem to be less common and less malignant among the Eskimo populations studied living in the regions at latitudes 70° than among those living in the more southern regions of Labrador.In January 1970 all the Eskimos who had been driving motor sledges were observed to have acute corneal and conjunctival epithelial lesions stainable with fluorescein.

Corneal degeneration in a congenitally diabetic inbred strain of mouse.

Corneal degeneration in a congenitally diabetic inbred strain of mouse.

EYES CONTAINING ANTERIOR CHAMBER ACRYLIC IMPLANTS-Reply

To the Editor. —Mr. Choyce's contributions in the field of anterior chamber implant surgery have been amply documented in his series of journal publications and in his monograph. In the course of his extensive clinical trials with the implantation procedure, he has reported an impressive reduction in complications over the years. His introduction of a modified presurgical evaluation, new implant designs, and refined surgical techniques have all contributed apparently to a decreased incidence of the sometimes disastrous complications described histologically in my paper (pupillary-block glaucoma, corneal degeneration, etc). In view of this, I must apologize for not indicating which Mark (I-VIII) was used in the five enucleated cases (cases 2, 7, 13, 14, and 16) identified as containing Choyce-type implants. In the two cases operated on by Mr. Choyce personally, (cases 13 and 14) both had received a Mark I implant. In the remaining three cases (2, 7, and 16),

Primary ocular prosthesis in patients undergoing evisceration, enucleation and socket reconstruction in north central Nigeria: A multi-center study

Background: Facial disfigurement especially of the eye can cause a lot of psychological impact on one's life. After evisceration or enucleation, primary ocular prosthesis (POP) not only provides immediate cosmetic rehabilitation, but also helps the individual regain self-confidence to resume normal life. The aim of this study was to assess the surgical outcome of evisceration and enucleation with POP in patients with endophthalmitis/panophthalmitis and allied conditions. Materials and Methods: This was a multi-center prospective study by the authors at three centers in Makurdi of patients undergoing destructive and socket reconstructive eye surgeries who had ocular prosthesis (OP [artificial eye]) inserted as a primary procedure from January 2010 to June 2014. Results: Eighteen patients had OP fitted at the operating table. There were 13 males (72%) and 5 females, with male to female ratio of 2.6:1. The median age was 45.5 years. Half of the patients 9 (50%) were farmers. Indications for surgery were infection 10 (55.6%), corneal degeneration 4 (22.2%) and one each had trauma, tumor, anophthalmos and shallow socket. Fifteen (83.3%) patients had evisceration. There were no postoperative infections during the follow-up period. There was small degree of enophthalmos in 16 (88.9%) and slight color mismatch in17 (94.4%). The OP movement with the fellow eye was fair in all the patients. Conclusion: Insertion of POP did not cause progression of infection in patients undergoing evisceration or enucleation. Where resources are not available for an orbital implant before prosthesis, POP can be fitted without the fear of progress of infection.

Experimental alpha-chymotrypsin glaucoma.

The injection of 750 units of α-chymotrypsin into the posterior chamber of the rhesus monkey eye resulted frequently in sustained elevation of the intraocular pressure. Retinal and neural degeneration, typical of that encountered in spontaneous human and experimental animal glaucoma, was found. Central corneal degeneration was frequent and led to perforation. Atrophy of the ciliary body was a striking finding in monkeys that developed glaucoma, and was present as early as three days after instillation of the enzyme. It is suggested that the pressure elevation was the consequence of ciliary body damage.

Encyclopedie medico-chirurgicale: Ophtalmologie

This publication is part of a loose-leaf system of medicine and surgery, including the specialties. The present supplement, therefore, is not a complete survey of ophthalmology but consists of a series of informative reports by various French ophthalmologists on examination and diseases of the cornea, uveal afflictions, enucleation and evisceration, retinal detachment, and optic nerve tumors. Although the amount of detail varies, the articles are characterized by their comprehensive quality. Bonamour and Audibert have an interesting discussion of corneal dystrophies and degenerations, while Hervouet describes very well the pathologic anatomy of retinal detachments. There is also a paper dealing with the expert in ophthalmology by Max Le Roy,Juge au Tribunal de Grande Instance de la Seine. Included with the supplement are brief bulletins on new developments in other ophthalmic problems. These bulletins are to be added to previous communications. Not having seen these earlier communications, the reviewer cannot comment

The lattice type of familial corneal degeneration; a histopathologic study.

Corneal tissue obtained after penetrating keratoplasty from two patients with the rare lattice type of familial corneal degeneration have provided the material for this histopathologic study. Although the clinical and biomicroscopic characteristics of this type of corneal degeneration are well known, only two reports of the histologic changes can be found in the English literature, 1,2 and in one of these 2 the nature of the degeneration remains in doubt. Some authors 3,4 have contended that all types of familial corneal degeneration are of similar origin, since different forms have been seen in the same family. Furthermore, the histologic picture of the lattice type of corneal dystrophy appears to differ only quantitatively from that of the commoner nodular type. Dimmer, 5 who published his clinical description of this entity in the same year as Haab, 6 prepared a scraping from the cornea of one of his patients and found an