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At least 343 records · Page 19Linked to original sources
PubMed1990

Use of a specular microscope with pachymeter in ocular tolerance studies of eye drops in the rabbit. Evaluation of ocular tolerance of benzalkonium chloride in aqueous solution 0.01% and 0.1%.

Eye drops, unlike cosmetics or chemicals, only cause minor irritations which often prove difficult to objectively observe and assess. A specular microscope with pachymeter is used to measure corneal thickness, and to examine and photograph corneal endothelium in ocular tolerance studies in the rabbit. Rabbits were instilled 5 times a day for 16 days with BKC aqueous solution, 0.01% or 0.1% and subjected after anaesthesia to 4 corneal inspections (before treatment, 7th and 14th days of treatment, 5th day after treatment). Only the 0.1% concentration provoked an increase in corneal thickness. Thickening progressed during the treatment period (5.3% on day 7, 26% on day 14) and strongly regressed 5 days after treatment stopped (3%). A slit lamp examination revealed very light or light corneal opacities, but the correlation between corneal thickening ratio and opacity was poor (r = 0.62).

Animals↗
PubMed1986

Schnyder's dystrophy. Progression and metabolism.

In the first long-term cohort study of Schnyder's corneal dystrophy the authors examined affected and unaffected members of two unrelated families in 1975 and 1976 respectively, and again in 1984. They identified carriers, catalogued changes in the diffuse and crystalline corneal opacities which characterize this dystrophy and analysed the patient's lipid metabolism. Corneal opacities never regressed. Progression was more frequent in diffuse than in crystalline opacities. Both crystalline and diffuse opacities reappeared and progressed following penetrating keratoplasty. Mean cholesterol levels in the carrier group were above normal and six had a moderate type IIa dyslipoproteinemia; conversely, two carriers had low apo B. The degree of corneal opacification showed no relationship to dyslipoproteinemia. Schnyder's corneal dystrophy appears to involve the corneal lipid metabolism only and not to be a systemic disease.

Adolescent↗
PubMed2004

Evaluation of a new bioadhesive copolymer (ADAL) to seal corneal incisions.

OBJECTIVE: To evaluate the efficacy and clinical tolerance of a new acrylic copolymer tissue adhesive, ADAL, in corneal surgery. METHODS: Corneal incisions were performed on 24 New Zealand albino rabbits. The incision was either sealed with ADAL bioadhesive, hydrated with balanced salt solution, or closed with 10-0 nylon surgical sutures. The incisions underwent weekly tensile strength testing and clinical, histopathologic, and confocal microscopy evaluations. RESULTS: Clinical evaluation revealed good sealing and no incision leakage in any group. There was no anterior chamber reaction in any case. Compared with the hydrated group, there was somewhat more incisional vascularization and localized corneal opacity in the ADAL group, but there were no cases of severe corneal opacity or neovascularization. On histologic analysis, a slightly larger inflammatory reaction was noted in the ADAL group compared with the hydrated group. Tensile strength during the first week was statistically significantly greater in the ADAL group (2.93 Newtons) than in the control groups (1.40 Newtons, hydrated group; 1.43 Newtons, sutured group) (P < 0.001). Confocal microscopy study revealed a unique dendritic keratocyte shape and structure resembling shiny crystalline particles after disappearance of the adhesive from the cornea. CONCLUSIONS: Corneal surgical incisions sealed with ADAL adhesive have superior tensile strength in the first postoperative week compared with incisions closed with sutures or hydrated with salt solution. Thereafter, findings in both groups became similar. The use of ADAL adhesive was not associated with any deleterious effects during the corneal incision-healing process compared with hydration or sutures.

Acrylates↗
PubMed1993

[Molecular defects in familial LCAT deficiency].

Lecithin: cholesterol acyltransferase (LCAT) is the enzyme that catalyzes the esterification of free cholesterol in plasma lipoproteins. Familial LCAT deficiency, which is a rare hereditary disorder of lipid metabolism, inherited as an autosomal recessive trait, is characterized by corneal opacity, anemia and frequently, though not invariably, renal failure. Recently, LCAT cDNA and gene have been cloned. Studies on DNA samples from unrelated patients with familial LCAT deficiency and fish eye disease, which is characterized by severe corneal opacity alone, revealed both diseases to be caused by respective mutations of the LCAT gene. It is suspected that defect or functional abnormality of LCAT, caused by these genetic defects, underlie the various clinical and biochemical characteristics observed in LCAT deficiency or fish eye disease.

Amino Acid Sequence↗
PubMed1989

[Corneal crystalline deposits in multiple myeloma].

Two cases of multiple myeloma with corneal opacity were reported. Their chief complaint was blurred vision, and general check-up performed prior to cataract operation revealed that one case had multiple myeloma of IgG-kappa and another, of IgG-lambda type. Two corneal buttons obtained at the time of lamellar keratoplasty operations in the IgG-kappa case were studied immunohistopathologically as well as electron microscopically. Corneal opacity observed with a slit lamp was localized at the anterior stroma of both corneas. Immunohistological studies revealed that the deposit was IgG-kappa chain. Transmission electron microscopy disclosed electron-dense extracellular deposits that exhibited a honeycomb appearance and parallel linear structures with a periodicity of 12nm.

Aged↗
PubMed1992

Paraformaldehyde-induced keratitis after photorefractive keratectomy.

We examined three patients who developed keratitis after myopic photorefractive keratectomy. All patients were treated on the same day and in all three cases paraformaldehyde tablets were used for disinfection of the excimer laser iris cone. All patients developed an intense postoperative corneal inflammation that resulted in corneal opacities. In the first patient, the opacities were central and persisted for at least 4 1/2 months postoperatively. He became more myopic than before the operation. His best spectacle-corrected visual acuity worsened by four Snellen lines. In the other two patients, the corneal opacities were paracentral and of less density. Six months postoperatively, these opacities were barely seen. In these two patients the postoperative best spectacle-corrected visual acuity remained unchanged or improved one Snellen line compared to the preoperative level. In all three patients, astigmatism increased postoperatively. These observations suggest that paraformaldehyde tablets are not safe for the disinfection of the excimer laser iris cone.

Adult↗
PubMed1998

Photorefractive keratectomy for myopia in the setting of adenoviral subepithelial infiltrates.

PURPOSE: To report a patient with persistent subepithelial corneal opacities 18 months after adenoviral keratoconjunctivitis who underwent photorefractive keratectomy for the correction of myopia. METHODS: Case report, review of medical literature, and slit-lamp photography. RESULTS: The patient underwent photorefractive keratectomy in each eye, 1 week apart, with ablation of central corneal opacities and resultant best-corrected visual acuity of BE, 20/20. Symptomatic subepithelial stromal infiltrates recurred in the peripheral but not the central cornea of each eye 3 months after laser treatment. CONCLUSIONS: Photorefractive keratectomy was successful in the correction of myopia and prevented the recurrence of adenoviral subepithelial corneal infiltrates within the laser-treated central cornea.

Adenovirus Infections, Human↗
PubMed1995

The incidence of corneal abnormalities in the Silicone Study. Silicone Study Report 7.

OBJECTIVE: To determine factors that were prognostic of corneal abnormalities in eyes following surgery for severe proliferative vitreoretinopathy. DESIGN: Subgroup analysis of the Silicone Study. SETTINGS: Community and university-based ophthalmology clinics. MATERIALS: Eyes with attached maculae at the 24-month follow-up examination that did not have a pre-existing corneal abnormality. INTERVENTIONS: Vitrectomy surgery with long-acting gas or silicone oil. OUTCOME MEASURES: Epithelial and/or stromal edema, corneal opacity and/or previous corneal transplant. RESULTS: The incidence of corneal abnormalities at 24 months was 27% and did not differ significantly between treatment groups. Prognostic factors were preoperative aphakia or pseudophakia (P = .003), preoperative iris neovascularization (P = .006), reoperation (P = .001), the absence of a fluid/gas exchange (P = .03), corneal touch by silicone oil (P = .02), and the presence of aqueous cells (P = .009) or aqueous flare (P = .08). In a multivariate analysis, independent prognostic factors were iris neovascularization (relative risk [RR] = 13.1), aphakia or pseudophakia (RR = 3.0), postoperative aqueous flare (RR = 5.4), and reoperations (RR = 3.4). Corneal abnormalities were correlated with poor visual acuity and hypotony (P < .001). CONCLUSIONS: To our knowledge, this is the first study to document that the incidence rates of corneal abnormalities are equivalent between oil and gas. The incidence of corneal abnormalities in gas-filled eyes was higher than expected, and remained high in oil-filled eyes, despite the use of an inferior iridectomy. Successful surgical repair of the retinal detachment with a single operation, and prevention and early management of corneal touch by silicone oil should help to prevent corneal abnormalities. If rubeosis iridis or severe aqueous flare is present, preoperative treatment with intense topical and possibly periocular steroids might reduce inflammation, which might mediate corneal damage.

Adult↗
PubMed2002

Autologous limbal grafting combined with deep lamellar keratoplasty in unilateral eye with severe chemical or thermal burn at late stage.

PURPOSE: To evaluate the efficacy of autologous limbal transplantation (ALT) combined with deep lamellar keratoplasty (DLK) for ocular surface reconstruction and corneal clarity recovery in eyes with severe late-stage chemical or thermal burns. DESIGN: Retrospective, noncomparative, interventional case series. PARTICIPANTS: Thirty-nine eyes of 39 patients with a history of severe chemical or thermal burns over 6 months (mean, 47 +/- 28.7 months) exhibiting corneal vascularization, conjunctivalization, and heavy corneal scarring were treated at two university hospitals. METHODS: Surgical procedures included excising epibulbar fibrous tissue, clearing the fibrovascular membrane over the cornea, deep removal of corneal stroma 7.5 to 8.0 mm in diameter, exposing Descemet's membrane in the pupillary area, grafting a corneal button, transplanting autologous limbal and conjunctival epithelial grafts, and making a temporary tarsorrhaphy. MAIN OUTCOME MEASURES: Integrity of ocular surface recovery, postoperative corneal epithelial stability, optical corneal clarity, and best-corrected visual acuity were the outcome measurements. RESULTS: Thirty-four of 39 eyes that received ALT combined with DLK met the criteria of the study. Of 34 operated eyes, full corneal epithelialization was achieved in 19 eyes (55.9%) within 5 days and in 32 eyes (94.1%) within 7 days after surgery. Delayed epithelial healing occurred in two eyes (5.9%). The reconstructed corneal surface remained stable, and the renewed epithelium was characterized cytologically by nonkeratinized squamous cells without goblet cells. After surgery in 11 of 34 eyes, fluid was identified between Descemet's membrane and the donor corneal graft, resulting in a pseudochamber that completely resolved in 10 eyes within 30 days. In one patient, a persistent pseudochamber was present for 28 months. After surgery, transparent cornea especially in the pupillary area was accomplished in 29 eyes, whereas mild cornea clouding, nebulomacular corneal opacity, and heavy corneal scarring were observed, respectively, in three eyes. In addition, corneal endothelial decompensation was identified in two eyes and demonstrated persistent corneal epithelial and stromal edema. Remarkable improvement of postoperative vision was achieved in 30 eyes. Four eyes without postoperative improvement in vision were regrafted by penetrating keratoplasty at least 6 months after the original ALT and DLK surgery. CONCLUSIONS: Autologous limbal grafting combined with DLK simultaneously can restore a normal and stable ocular surface, create clear central cornea, and remarkably enhance visual acuity after severe chemical or thermal burns.

Adolescent↗
PubMed1982

Anterior chamber tube shunt to an encircling band in the treatment of neovascular glaucoma.

A new procedure for neovascular glaucoma that has reduced intraocular pressure (IOP) significantly and has caused relatively few postoperative complications is introduced. Aqueous is shunted to the reservoir of an encircling no. 20 silicone band from which fluid is postulated to diffuse into the orbit. The anterior chamber tube shunt to an encircling band (ACTSEB) procedure was conducted in 19 eyes with neovascular glaucoma. After surgery 18 of the 19 eyes (95%) followed for periods ranging between five and 26 months (mean: 59 weeks) had controlled IOP using less than or equal to 20 mm Hg as normal, and one eye had partial control (eye 9) at 26 mm Hg. Despite the preoperative use of atropine sulfate, timolol maleate, acetazolamide, and 20% mannitol, the patients' average preoperative IOP was 54.1 mm Hg. After surgery the average IOP fell, dramatically, to 16.2 mm Hg. The mean change in IOP was 37.9 +/- 9.8 (SD). This change is statistically significant by the paired t-test, P less than 0.01. Minimal postoperative medications were required for pressure control. Postoperative complications included hyphema (21%), prolonged flat chamber (74%), localized peripheral lens opacity (5%), localized corneal opacity (5%), and possible acceleration of progressive cataract formation (25%). Results of current surgical procedures used to manage neovascular glaucoma are compared to the ACTSEB results.

Adult↗
PubMed1995

Optical sectioning of the cornea with a new confocal in vivo slit-scanning videomicroscope.

PURPOSE: The purpose of this article is to introduce a newly developed confocal in vivo slit-scanning microscope for continuous recording and real-time imaging of the various corneal subsegments of the patient's eye with high microscopical resolution and adequate contrast. METHODS: One-dimensional confocal slit-scanning videomicroscopy of the human cornea was performed with an instrument mainly consisting of a scanning module, an image-intensifier video camera, a video monitor, and a synchronization unit for matching optical scan and video cycle with respect to frequency and phase. Light intensity or fluorescence intensity profiles through the cornea could be obtained by microphotometric recording of part of the imaging light. An immersion contact technique using an isotonic tear replacement liquid with thixotropic properties avoids any mechanical contact between the front lens of the microscope objective and the corneal surface. RESULTS: In normal human eyes, the corneal micromorphology could be made visible with satisfactory lateral and axial resolution and with good contrast. The separately focussed sections of the cornea showed the endothelial cells, the superficial, intermediary, and basal cells of the epithelium, as well as stromal keratocytes and nerves. Even in eyes with significant corneal opacities resulting from corneal edema, the endothelial pathology could be imaged with sufficient contrast. CONCLUSION: The in vivo slit-scanning videomicroscopy offers real-time noninvasive and noncontact serial imaging of corneal subsegments with resolution and imaging contrast. Thus, an important step toward using confocal scanning microscopy for corneal diagnosis seems to be done.

Cornea↗
PubMed1998

Management of ophthalmic complications of homocystinuria.

OBJECTIVE: To determine the safety and efficacy of surgical versus medical management in the treatment of ophthalmic complications of homocystinuria, and also to document ocular complications of homocystinuria other than lens dislocation. DESIGN: Retrospective case series. PARTICIPANTS: Forty-five patients with ophthalmic complications of homocystinuria participated. INTERVENTION: Eighty-four surgical procedures were performed on 40 patients. There were 82 procedures done with the patients under general anesthesia and 2 with the patients under local anesthesia. Medical therapy was attempted initially in all patients with lens dislocation and was the sole therapy used for five patients. MAIN OUTCOME MEASURES: Complications resulting from medical or surgical treatment and final visual acuity were studied. RESULTS: All patients had a history of lens subluxation or dislocation. Fourteen (31%) were receiving dietary treatment at the time of presentation and 29 (64%) were mentally retarded. Eighty-two procedures were performed with the patients under general anesthesia with 2 surgical complications and 1 postsurgical complication. Lens dislocation into the anterior chamber was the most frequent indication for surgery (50%) followed by pupillary block glaucoma (12%). Prophylactic peripheral iridectomy was not successful in preventing lens dislocation into the anterior chamber in five patients. Anesthetic precautions such as stockings to prevent deep venous thrombosis, preoperative hydration, or aspirin were given in 85% of cases. Other common ophthalmic complications found include optic atrophy (23%), iris atrophy (21%), anterior staphylomas (13%), lenticular opacities (9%), and corneal opacities (9%). CONCLUSION: Laser iridectomy was unsuccessful in preventing lens dislocation into the anterior chamber. With appropriate anesthetic precautions and modern microsurgical techniques, the risks associated with the surgical management of ocular complications of homocystinuria are reduced. Surgical treatment should be considered, especially for cases of repeated lens dislocation into the anterior chamber or pupillary block glaucoma. If a conservative, nonsurgical approach is undertaken, these patients must be observed carefully for repeat episodes of lens dislocation.

Adolescent↗
PubMed2003

Kindler syndrome.

Kindler syndrome is a rare genodermatosis characterized by acral bullae and photosensitivity. The photosensitivity improves with advancing age and results in progressive poikiloderma and cutaneous atrophy, and many additional features have also been described. This report describes two male Kindler syndrome patients with classical features of acral blistering and photosensitivity in childhood, and subsequent development of poikiloderma, leukokeratosis of oro-ano-genital mucosae, phimosis and meatal stenosis. The first patient had additional ophthalmic features of chronic simple conjunctivitis caused by persistent irritation, multiple stromal nebular corneal opacities and thickened corneal nerves. The second patient showed skeletal changes, namely a dome-shaped skull (turri-cephaly), bifid fourth rib, missing fifth rib, short fourth and fifth metacarpals and mandibular abnormalities. This is the first report of such ophthalmic and skeletal features of Kindler syndrome.

Adult↗
PubMed2005

[Combined penetrating keratoplasty with keratolimbal allograft transplantation in the treatment of severe corneal burns].

OBJECTIVE: To study the clinical results of combined penetrating keratoplasty with keratolimbal allograft transplantation in the treatment of severe corneal burns. METHODS: The present study consisted of 35 eyes (34 patients) with full thickness corneal opacities and extensive corneal conjunctivalization after severe corneal burns. The duration between the injury and the time of presentation ranged from four months to 23 years. Group A: Combined penetrating keratoplasty (PK) with annular keratolimbal allograft transplantation (KLAT) was performed in 19 eyes (18 patients). Group B: Total PK with a scleral rim was performed in 16 eyes (16 patients). Post-operative visual acuity, intraocular pressure, graft rejection and complications were monitored. The average follow up time was 24 (range from 15 to 28) months. RESULTS: (1) Vision: The number of eyes that obtained best corrected visual acuity > 0.05 was 18 eyes (95%) in group A and 14 eyes (84%) in group B at 6 months postoperatively (P = 0.582); 16 eyes (88%) in group A and 6 eyes (38%) in group B at 12 months (P = 0.006); 12 eyes (63%) in group A and 3 (7%) in group B at 24 months (P = 0.016). (2) Graft rejection: Nine allografts (47%) in group A and 8 grafts (50%) in group B developed limbal stem cell rejection (P = 1.000); 6 allografts (32%) in group A and 11 allografts (69%) in group B developed endothelium rejection (P = 0.044). The difference of endothelium rejection rate between group A and B was not significant at different times postoperatively. (3)COMPLICATIONS: Corneal epithelium defect occurred in 2 eyes (11%) in group A and 7 (44%) eyes in group B (P = 0.049); hyphema occurred in 2 eyes (11%) in group A and 8 eyes (50%) in group B (P = 0.022); hypotony occurred in 1 eye (5%) in group A and 6 eyes (38%) in group B (P = 0.032). CONCLUSIONS: PK combined with KLAT is an effective treatment for severe corneal burns at a late stage irrespective of the etiology. This procedure can restore visual function in severely damaged eyes. Patients treated with PK combined with KLAT show less complication and better prognosis as compared with patients treated with total PK with a scleral rim.

Adolescent↗
PubMedDate not supplied

[Ocular morbidity in Palestine].

Examinations of 1427 subjects (2848 eyes) on the Western Bank of the Jordan and in the Ghaza sector have revealed a high incidence of ophthalmic diseases, particularly of conjunctivitis, cataracts (nuclear among other ones), corneal opacities, pigmented retinal dystrophies, diabetic retinopathies, congenital conditions. Blindness resulted mostly from corneal opacities, most often developing after trachoma, and from congenital diseases of the eyes. Marriages between relatives appear to play an essential role in the development of congenital diseases of the eyes, as well as of pigmented abiotrophy of the retina.

Blindness↗
PubMed1996

[Penetrating keratoplasty in children].

OBJECTIVE: The study was designed to approach the operative techniques of penetrating keratoplasty (PKP) in children and the influential factors on the rate of graft clarity. METHODS: PKP was performed on 33 eyes of 30 children whose corneal opacities resulted from various causes and they were followed for 6 months to 3 years. RESULTS: The rate of graft clarity was 66.7% and 44.8% of these eyes were relieved from blindness. The poorest results achieved were in cases with congenital corneal opacity and the main cause of graft failure is endothelial immune rejection. CONCLUSION: Although the surgical results in children are poorer than that in adults, from the concern of prevention of amblyopia and cosmetic problem, it is necessary to perform the operation earlier.

Adolescent↗
PubMed2003

Bilateral central anterior stromal opacity of the cornea: dystrophy or degeneration?

PURPOSE: To describe a bilateral, central, oval corneal opacity not resembling any known corneal degeneration or dystrophy. METHODS: Ophthalmic examination, corneal topography, and pachymetry. RESULTS: A 30-year-old woman presented complaining of blurred vision. Biomicroscopic examination revealed bilateral, centrally located, oval, diffuse opacification of the anterior corneal stroma. Corneal topography showed slightly paracentral corneal flattening and irregular astigmatism in both eyes. Pachymetry indicated thinning of the central cornea in the left eye. No evidence of systemic disease was found. Family members had no corneal abnormalities. CONCLUSIONS: This unusual keratopathy closely resembles climatic proteoglycan stromal keratopathy. However, it is not clear whether the condition should be described as a dystrophy or degeneration.

Adult↗