Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Corneal Edema”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1986

The role of the polymorphonuclear leukocyte in the induction of corneal edema.

Corneal inflammation is frequently associated with the development of corneal edema. It has been suggested the development of corneal edema might in some way be related to the presence of polymorphonuclear leukocytes (PMNLs) within inflamed corneas. In the present studies, it was found that corneal thickness markedly increased after experimental infection with Pseudomonas aeruginosa, but in guinea pigs made neutropenic by whole body irradiation, significantly less of an increase in corneal thickness occurred. Furthermore, corneas from non-neutropenic animals experimentally infected with P. aeruginosa consistently showed a greater increase in water content than did infected corneas from neutropenic animals. Over the first 48 hr of infection, the increase in corneal water was directly proportional to the corneal ingress of radiolabelled PMNLs. Corneal inflammation induced by intracorneal injection of the PMNL chemotactic agents phorbol myristate acetate (PMA) or endotoxin was also associated with a significant increase in corneal water compared with neutropenic animals. These data strongly suggest that activated PMNLs in the cornea are responsible for the induction of corneal edema in infected corneas.

Animals↗
PubMed1986

Fuchs' corneal dystrophy. A clinicopathologic study of the variation in corneal edema.

Corneal buttons from six patients with Fuchs' dystrophy had varying degrees of clinical edema measured in most cases by preoperative optical or ultrasonic pachymetry. These were sectioned in the operating room so that histologic correlations could be made. Histologically, marked thickening of Descemet's membrane and abnormal corneal endothelium corresponded to areas of severe clinical edema and were usually located in the central and paracentral regions. Descemet's membrane displayed multiple prominent guttata of varying size and shape, either facing the anterior chamber, or buried within multilaminar Descemet's membrane. In some corneas, aggregates of 10 nm fibrils were seen at the edges of guttata, corresponding to areas that stained for oxytalan fibrils. The endothelium was attenuated underlying the guttata. Clinical edema was not present unless accompanied by marked thickening of Descemet's membrane with multiple guttata and attenuation of corneal endothelium. The peripheral cornea was relatively clear clinically and showed minimal histologic changes.

Aged↗
PubMed1979

Corneal edema with several hard corneal contact lenses.

Five patients were each fitted with polymethylacrylate (PMMA), BP Flex, and Polycon corneal contact lenses of the same dimensions. Corneal edema was monitored with a slit-lamp biomicroscope and pachometer. Lenses were worn in a double-masked and random sequence for periods of 6 hr. Patients developed less corneal edema with Polycon lenses than with PMMA lenses. There was no significant difference in corneal edema with PMMA and BP Flex lenses. Those patients who developed little corneal edema with optimum-fitting PMMA lenses also developed little edema with the BP Flex and Polycon lenses. Steeper-fitting PMMA and BP Flex lenses produced more corneal edema than optimum-fitting lenses made of the same materials, while steeper-fitting Polycon lenses produced only slightly more edema than the optimum-fitting Polycon lenses.

Adult↗
PubMed1992

The role of viscoelastics, cannulas, and irrigating solution additives in post-cataract surgery corneal edema: a brief review.

Corneal clarity is dependent upon maintenance of the corneal endothelial barrier and pump. Mechanical trauma is usually considered to be the most significant factor in corneal endothelial damage during cataract surgery resulting in postoperative corneal edema. However, corneal decompensation out of proportion to the degree of trauma seen during surgery does occur. These cases of unexpected corneal edema can often be traced to unrecognized preoperative endothelial dysfunction or to toxicity of intraocular medications used during surgery. This paper reviews the role of viscoelastics in reducing surgical trauma, their toxicity, and the risks of toxicity inherent in the use of re-usable cannulas and irrigating solution additives. Disposable cannulas should be used whenever possible. The use of re-usable cannulas with viscoelastics is highly likely to result in toxic residues being introduced onto the eye, and must be avoided. Irrigating solution additives should be tested with in-vitro human donor cornea perfusions prior to clinical use.

Cataract Extraction↗
PubMed1979

Vision through an abnormal cornea: a pilot study of the relationship between visual loss from corneal distortion, corneal edema, keratoconus, and some allied corneal pathology.

Visual function was assessed by classic acuity measures as well as contrast thresholds over a wide spatial frequency range for subjects with experimentally induced corneal distortion and induced corneal edema. These results were compared with similar results for patients with uniocular keratoconus, bilateral keratoconus, and allied corneal pathology. Distortion and edema were found to produce characteristically different types of contrast attenuation at threshold (amplitude) and have quite different suprathreshold abnormalities (phase) for objects within the resolution limit and therefore could form the basis of a useful functional classification of the visual degradation from corneal pathology.

Cornea↗
PubMed1992

National outcomes of cataract extraction. III. Corneal edema and transplant following inpatient surgery.

We analyzed the likelihood of rehospitalization for corneal edema or corneal transplantation in all 338,141 Medicare beneficiaries older than 65 years who were admitted to US hospitals for cataract extraction in 1984. The rate of rehospitalization for corneal edema or transplant within 4 years of intracapsular cataract extraction was 1.4%, almost twice the rate associated with extracapsular extraction (0.63%) or phacoemulsification (0.62%; P less than .0001). No significant difference in the rate of corneal transplantation was detected between those undergoing extracapsular cataract extraction and those undergoing phacoemulsification. Among patients who had intracapsular cataract extraction, those who underwent concurrent intraocular lens implantation surgery had a higher rate of rehospitalization for corneal edema or transplantation than those who did not (1.11% vs 0.86%; P = .0003). However, this difference is only manifest starting at about 3 years after surgery. Among patients who underwent extracapsular cataract extraction and phacoemulsification, however, those who underwent intraocular lens implantation during surgery had a lower rate of corneal edema or transplantation than those who did not (0.47% vs 0.74%; P less than .0001). This difference was seen almost immediately after surgery. Cataract surgery accompanied by anterior vitrectomy was associated with a threefold increase in the 4-year rate of corneal edema or transplantation compared with cataract surgery alone (2.42% vs 0.87%; P less than .0001).

Aged↗
PubMed1984

Mechanisms of visual loss in corneal edema.

Although visual disability from corneal edema is a well-recognized clinical finding, it is not easily confirmed by routine visual assessment. A more reliable assessment of visual changes resulting from corneal edema of varying origins is achieved by measurement of changes in the contrast sensitivity function. The measurements can be sensitized by the presence of a glare source to allow a more accurate determination of the nature of the visual loss. Even in the absence of a measurable loss of visual acuity, corneal edema leads to diminished visual function. The magnitude and type of this loss is dependent on the origin of the edema and the site of the corneal response.

Corneal Diseases↗
PubMed2004

Permanent corneal edema resulting from the treatment of PTK corneal haze with mitomycin: a case report.

A 39-year-old man underwent phototherapeutic keratectomy via excimer laser for recurrent corneal erosions secondary to basement membrane dystrophy with the subsequent development of irregular astigmatism and central stromal opacity. The cornea was scraped and treated with 0.02% mitomycin C using a total of 14 drops over a period of 6 days. Corneal edema developed as a consequence of low endothelial cell count with dysfunctional cells. A corneal transplant restored acuity of 20/20 with binocular vision. It is believed that the underlying endothelium was exposed to toxic doses of mitomycin C sufficient to damage and destroy vital cells. The author reports this case not to criticize the use of mitomycin C in visually disabling post-phototherapeutic keratectomy or photorefractive keratectomy haze but to apprize colleagues of a potential pitfall. The author believes that the use of mitomycin C as a 1-time application at the end of surgery is a safe and valuable adjunct to recover vision when no other is known. However, continued topical application of mitomycin C to the central cornea, in the face of an epithelial defect or an epithelium with inadequate barrier function, increases the risk of endothelial damage.

Adult↗
PubMed2004

Reversible amantadine-induced corneal edema in an adolescent.

PURPOSE: To document reversible corneal edema caused by amantadine in a pediatric patient. METHODS: A 14-year-old boy with a neurologic tremor was referred for bilateral visual loss. Our examination disclosed bilateral corneal edema without ocular inflammation. Pachymetry confirmed significantly increased corneal thickness above 900 microm. RESULTS: Review of the patient's medical information revealed recent institution of amantadine as a means to control the patient's tremor. On cessation of this agent, rapid resolution of corneal edema and recovery of visual acuity occurred. Repeat pachymetry measurement revealed normal corneal thickness. CONCLUSION: In cases of corneal edema and in the absence of any identifiable ocular causes, a review of toxic effects of systemic medication should be undertaken. Amantadine can cause corneal decompensation and needs to be considered as part of the differential diagnosis of corneal edema.

Adolescent↗
PubMed1991

Corneal edema induced by bis (tributyltin) oxide.

Corneal edema induced by bis (tributyltin) oxide (TBTO) was studied with an electron microscope and the accumulation sites of tin were determined with an X-ray microanalyzer. Male Wistar rats received an intramuscular injection of 0.5 ml/kg TBTO. After time intervals of 2, 4, 6, 8, 10, 12 h after injection, corneas were isolated and provided for electron microscopy. Corneas from untreated rats served as controls. Marked swelling of mitochondria in the corneal endothelial cells occurred at 4 h after TBTO injection. The corneal edema appeared in the endothelial layer and the stroma at 6 h after injection. By X-ray microanalysis, Sn peaks were obtained from swollen mitochondria in the endothelial cells. At 12 h after TBTO injection, edematous swelling of the corneal tissue became more advanced. These results indicated that parenterally administered TBTO accumulated in the mitochondria of corneal endothelial cells. The direct toxic effects of TBTO on the mitochondria might cause the interference with active pump function of endothelial cells and induced the corneal edema.

Animals↗
PubMed1995

Relationship between corneal edema and topography.

We found that corneal edema can occur without significant concomitant changes in central and peripheral corneal topography. We examined the relationship between corneal edema and corneal topography in 10 subjects with normal ocular examinations. Baseline pachymetry and topographic measurements for both eyes of each patient were obtained. The right eye of each subject was exposed to an anoxic environment for 2 hours using a nitrogen chamber goggle. The left eye served as control. Optical pachymetry and computerized corneal topographic measurements were taken for both eyes immediately after removal of the nitrogen chamber goggle. All corneas exposed to the nitrogen chamber were thickened in all areas after removal of goggles. Average percent thickening per area was: 16.4% centrally, 6.3% nasally, 6.0% temporally, 6.3% superiorly, and 9.2% inferiorly. Corneas exposed to the nitrogen chamber demonstrated no significant topographic changes, except in the nasal area where the corneal power lessened. Furthermore, there was no significant correlation between corneal thickening in any area measured and changes in corneal topography. Control corneas did not thicken or demonstrate significant topographic changes.

Adult↗
PubMed1983

Intersubject difference in corneal edema response to hypoxia.

A common clinical observation is that some patients are more prone to the development of corneal edema than others. To test the validity of this observation, 30 subjects each wore an experimental hydrogel lens designed to stress corneal metabolism by reducing oxygen availability and thereby producing measurable amounts of corneal edema. The corneal edema response varied from 20.3 (3.7%) to 55.1 microns (12.2%) after 3 hr of opened-eye lens wear. Mean intrasubject reliability was +/- 3 microns (0.6%). Corneal edema response to the experimental lens was well correlated with corneal edema response to a conventional thin hydrogel lens (r = 0.83). These results support the conclusion that some patients are more prone than others to developing corneal edema and that these patients can be identified by measuring corneal thickness changes after a 3-hr wearing trial with a thick HEMA lens of standard dimensions.

Adult↗
PubMed1989

Pseudophakic corneal edema. An 11-year study of its development, incidence, and treatment.

This paper studies the appearance and development of pseudophakic corneal edema (PCE) in a series of 840 patients referred for keratoplasty for corneal edema. There were no cases of PCE in 100 eyes with corneal edema studied between 1960 and 1970. In 200 cases of corneal edema studied between 1978 and 1980, there were 30 eyes with PCE (15%). The disease has gradually increased to 56% of all cases of corneal edema seen in 1986. A tendency of PCE to decrease has been noted in the last 2 years. The high incidence of PCE in recent years, which is the main reason for keratoplasty today, seems to be related to the use of closed loop anterior chamber lenses. Fuchs' dystrophy, which formed the bulk of cases of corneal edema, may be present in many cases of PCE. results of keratoplasty with intraocular lens (IOL) removal or exchange provided better than 80% good results in a group of 230 cases followed from 1 to 7 years with visual improvement better than 20/100 in over 50% of cases. The removal of an intraocular lens causing progressive visual symptoms is advised even at the risk of causing corneal edema.

Anterior Chamber↗
PubMed1989

Problems associated with penetrating keratoplasty for corneal edema in congenital glaucoma.

Corneal edema from congenital glaucoma is a rare indication for penetrating keratoplasty. We report the complications and problems associated with eight consecutive penetrating keratoplasties performed in adult eyes with a history of congenital glaucoma. Only 25% of the eyes achieved 20/40 or better vision after surgery. These generally poor results can be attributed to previous glaucomatous optic nerve damage, to complications related to previous surgery, and possibly to amblyopia. The most common surgical complication was postoperative elevation of intraocular pressure, which occurred in all the cases (8/8 eyes), and required permanent augmentation of glaucoma medications in seven eyes (88%), and glaucoma surgery in four eyes (50%). Two eyes (25%) developed corneal graft failure, one from immune rejection and the other from severe postoperative glaucoma necessitating cyclocryotherapy. In view of these complications and the multiple impediments to good postoperative vision, we advise that penetrating keratoplasty be reserved for patients with severe visual disability whose preoperative glaucoma is well controlled.

Adolescent↗
PubMed1977

The effect of corneal edema on visual function.

Corneal edema was produced by atmospheric-induced anoxia and the visual effect was assesed by conventional acuity tests and compared with contrast sensitivity measurements. For the degree of edema which this technique produced, contrast sensitivity was depressed for only high spatial frequencies and could be considered in terms of equivalent defocus. This was not the case ofr a greater degree of edema which was simulated by a diffuser with a particle size that mimics the diffraction effects from an edematous cornea. Equivalent blur was not applicable, since low spatial frequencies were also affected and the letter and contrast sensitivity tests gave radically different results. In the light of these findings, the validity of the present letter acuity evaluation of visual function for patients in which intraocular scattering is involved is questioned.

Cornea↗
PubMed1983

Persistent corneal edema in the congenital rubella syndrome.

Corneal edema occurring in the congenital rubella syndrome can result from coexistent glaucoma or develop in the absence of an elevated intraocular pressure. We examined a 36-week-old female infant with documented congenital rubella syndrome who had bilateral corneal stromal edema without attendant congenital glaucoma. Histopathologic examination of the cornea revealed absent Descemet's membrane, deep interstitial keratitis, stromal corneal swelling, and deranged, focally absent endothelial cells. A viral infiltration of endothelium is postulated as the mechanism of the corneal edema and keratitis.

Cataract↗