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Biomedical subjects

J H Krachmer

Publications and source records attributed to J H Krachmer.

At least 19 recordsLinked to original sources

The effects of donor age on the outcome of penetrating keratoplasty in adults.

OBJECTIVE: The purpose of the study is to determine whether there is a higher incidence of complications in adult patients receiving corneas from pediatric donors compared to those receiving corneas from adult donors. DESIGN: The design is a follow-up of two matched cohorts. PARTICIPANTS: The outcome of penetrating keratoplasty in 29 adult patients (age 20 years of age and older) receiving pediatric donor corneas (range, 0-5 years) was compared to that of 29 control patients matched for recipient age and diagnosis who received adult donor corneas (range, 40-70 years). INTERVENTION: Chart review was performed. MAIN OUTCOME MEASURES: Graft rejection, postoperative keratometry, postoperative refractive cylinder, postoperative intraocular pressure, and graft failure due to rejection were measured. RESULTS: One or more allograft reactions occurred in 11 (37.9%) of 29 patients who received pediatric donor corneas compared to 2 (6.9%) of 29 patients who received adult donor corneas (P = 0.005, chi-square). There were a total of 20 rejection episodes in patients receiving pediatric donor corneas compared to a total of 5 rejection episodes in patients receiving adult donor corneas. The average postoperative keratometry was 46.1 diopters for the pediatric donor group and 44.0 diopters for the adult donor group (P = 0.03). There was no statistically significant difference in average refractive cylinder (P = 1.0), intraocular pressure (P = 0.26), or the incidence of graft failure due to rejection (P = 1.0) between the two groups. The average follow-up time for clear grafts was 58.3 months in the pediatric donor group and 59.9 months in the adult donor group. CONCLUSIONS: The incidence of allograft reactions and the postoperative corneal curvature is greater in adult eyes undergoing penetrating keratoplasty with young donor corneas compared to those undergoing penetrating keratoplasty with older donor corneas. There was no difference in the incidence of graft failure due to rejection between the two groups.

Adult↗

The role of topical corticosteroids in the management of Acanthamoeba keratitis.

PURPOSE: To clarify the role of topical corticosteroids in the management of Acanthamoeba keratitis. METHODS: The records of 38 patients diagnosed with Acanthamoeba keratitis at three institutions were retrospectively reviewed. RESULTS: After medical therapy alone, patients diagnosed within 1 month of symptom onset had an increased likelihood of being cured (p = 0.02) and attaining visual acuity of 20/60 or better (p < 0.01). Fourteen (73.7%) of 19 patients treated with topical corticosteroids at any time were cured after antiamoebal therapy alone, whereas five (26.3%) patients required penetrating keratoplasty for either persistent infection (n = 3) or perforation (n = 2). The mean antiamoebal therapy duration, excluding duration after keratoplasty if applicable, was 38.5 weeks. Thirteen (76.5%) of 17 patients treated with antiamoebal therapy without topical corticosteroids were medically cured, whereas four (23.5%) required penetrating keratoplasty for either persistent infection (n = 2) or perforation (n = 2). The mean antiamoebal therapy duration was 20 weeks. Although the mean antiamoebal therapy duration in the steroid-treated group was significantly longer than that in the non-steroid-treated group (p = 0.02), outcome after medical therapy between the groups was not significantly different. CONCLUSIONS: Topical corticosteroids were not associated with a higher rate of medical treatment failure in patients with Acanthamoeba keratitis. Rather, poor outcome was significantly related to diagnostic delays. Therefore prudent use of corticosteroids in selected patients with severe pain not responsive to analgesics or severe corneal or anterior chamber inflammation appears justified.

Acanthamoeba↗

Confocal microscopy findings of Acanthamoeba keratitis.

PURPOSE: Tandem scanning confocal microscopy was performed on two patients with Acanthamoeba keratitis to provide images detailing characteristic findings of the disease. Although tandem scanning confocal microscopy of Acanthamoeba has been described in previous reports, Acanthamoeba keratitis has not been fully characterized with this instrument. In vivo confocal micrographs showed the double-walled structure of the Acanthamoeba cyst and associated radial keratoneuritis (perineuritis). METHODS: We reviewed the records of two patients with a clinical diagnosis of Acanthamoeba keratitis, one with culture-proven Acanthamoeba and the other with a suspected Acanthamoeba infection. Slit-lamp biomicroscopy and in vivo tandem scanning confocal microscopy were performed. The images obtained were compared with images from patients without corneal disease. RESULTS: High-contrast round bodies suggestive of Acanthamoeba cysts, as previously described, and irregular forms suggestive of Acanthamoeba trophozoites were found by tandem scanning confocal microscopy. Additionally, we showed conclusively that under certain circumstances (that is, corneal scarring) tandem scanning confocal microscopy can resolve the double-walled structure of the Acanthamoeba ectocyst surrounding the endocyst. Furthermore, radial keratoneuritis was demonstrated, consisting of an irregularly swollen nerve fiber with probable amoebic infiltration. CONCLUSIONS: Confocal microscopy can be a useful, noninvasive imaging technique helpful in the study, diagnosis, and treatment of Acanthamoeba keratitis.

Acanthamoeba↗

Mottled cyan opacification of the posterior cornea in contact lens wearers.

PURPOSE: We studied patients who had mottled cyan-colored opacities of the cornea to better understand the cause and prognosis of this entity. METHODS: We reviewed examinations of patients who had a mottled cyan opacification of the cornea. Risk factors, including contact lens wear and exposure to heavy metals, were analyzed. Clinical findings, pachymetry specular microscopy, and progression of the abnormality were noted. RESULTS: Six patients who had a mottled cyan opacification at the level of Descemet's membrane were identified. These opacities were located in the peripheral and midperipheral cornea. All patients had bilateral findings, had visual acuities of 20/20 or better, and were asymptomatic. All patients had worn soft contact lenses bilaterally for periods ranging from seven to 14 years. CONCLUSION: All patients had the similar clinical appearance of a mottled cyan opacification at the level of Descemet's membrane in the peripheral cornea. Long-term contact lens wear appears to be associated; however, the exact cause is unclear.

Adult↗

Linkage of posterior polymorphous corneal dystrophy to 20q11.

Posterior polymorphous dystrophy (PPMD) is an autosomal dominant disorder of the cornea that is clinically recognized by the presence of vesicles on the endothelial surface of the cornea. The corneal endothelium is normally a single layer of cells that lose their mitotic potential after development is complete. In PPMD, the endothelium is often multi-layered and has several other characteristics of an epithelium including the presence of desmosomes, tonofilaments, and microvilli. These abnormal cells retain their ability to divide and extend onto the trabecular meshwork to cause glaucoma in up to 40% of cases. A large family with 21 members affected with PPMD was genotyped with short tandem repeat polymorphisms distributed across the autosomal genome. Linkage was established with markers on the long arm of chromosome 20. The highest observed LOD score was 5.54 (theta = 0) with marker D20S45. Analysis of recombination events in four affected individuals revealed that the disease gene lies within a 30cM interval between markers D20S98 and D20S108.

Chromosome Mapping↗

Bilateral herpes simplex virus type 2 keratitis: a clinicopathologic report with immunohistochemical and ultrastructural observations.

This report describes the clinical, histopathologic, ultrastructural, and immunohistochemical findings in two corneal buttons from a 13-year-old girl who developed bilateral progressive corneal stromal opacification during childhood. As determined by light microscopy, both corneal buttons were edematous with a chronic inflammatory infiltrate confined to the deep layers of the stroma. We detected intranuclear eosinophilic inclusions in some epithelial cells. We detected herpesvirus particles in stromal keratocytes and endothelial cells by transmission electron microscopy. Immunohistochemistry studies identified concurrent expression of specific herpes simplex virus type 2 antigen in corneal epithelial cells, in keratocytes in the deep layers of the stroma, and in endothelial cells. The cause of progressive bilateral stromal corneal opacification in this child was herpes simplex virus type 2 keratitis. This condition should be considered in the differential diagnosis of progressive, bilateral corneal opacification in children.

Adolescent↗

Three autosomal dominant corneal dystrophies map to chromosome 5q.

The two most common autosomal dominant dystrophies of the corneal stroma are lattice corneal dystrophy type I and granular dystrophy. A third autosomal dominant stromal dystrophy (Avellino) has also been recognized. Chromosome linkage analysis of four families with Avellino dystrophy mapped the disease-causing gene to chromosome 5q. Subsequent linkage analysis of two families with typical lattice dystrophy and two with typical granular dystrophy also revealed significant linkage with the same markers. Thus, each of three clinically and histopathologically distinct phenotypes is independently linked to 5q. The maximum combined lod score using all 114 affected patients was 28.6 with marker D5S393. None of the 14 known human amyloid-associated genes map to chromosome 5.

Alleles↗

Clinical findings in Brown-McLean syndrome.

The Brown-McLean syndrome is a clinical condition with corneal edema involving the peripheral 2 to 3 mm of the cornea. The edema typically starts inferiorly and progresses circumferentially, but spares the central portion of the cornea. Additionally, the edema is associated with a punctate orange-brown pigmentation on the endothelium underlying the edematous areas. Central cornea guttata is frequently seen. This condition occurs most frequently after intracapsular cataract extraction, but may also occur after extracapsular cataract extraction and phacoemulsification, or pars plana lensectomy and vitrectomy. Surgical complications and multiple intraocular procedures are frequently observed in these patients. Less frequently, the Brown-McLean syndrome can occur in eyes that have not had surgery. We studied the clinical characteristics of 43 affected eyes of 32 patients. New findings included Brown-McLean syndrome occurring in two eyes of a phakic patient with intermittent angle-closure glaucoma. Two eyes developed Brown-McLean syndrome after phacoemulsification and one eye developed peripheral edema after pars plana vitrectomy and lensectomy. Additionally, severe, infectious keratitis occurred after rupture of peripheral bullae in two eyes. Patients with this condition should be examined periodically and educated regarding the early clinical signs of corneal ulceration.

Adult↗

Enterococcal infectious crystalline keratopathy.

Two patients developed infectious crystalline keratopathy (ICK) 9 and 11 months after penetrating keratoplasty. In both cases, cultures yielded enterococcus sensitive to vancomycin. The first patient developed diffuse loss of corneal and conjunctival epithelia after 24 h of treatment with vancomycin eyedrops, whereas the second patient did not respond after 14 days of topical vancomycin therapy. Both patients eventually required penetrating keratoplasty. Enterococcus is a ubiquitous bacterium resistant to many antibiotics that should be suspected of causing ICK.

Aged↗

Topical cyclosporin A in the treatment of anterior segment inflammatory disease.

Topical cyclosporin A was used in the management of 43 patients with a variety of anterior segment inflammatory disorders that had failed corticosteroid treatment. Treatment with topical cyclosporin A ranged from 1 week to 43 months, with a mean treatment period of 13 months. Thirty-five patients (81%) with disorders including high-risk keratoplasty, atopic and vernal keratoconjunctivitis, ligneous conjunctivitis, ulcerative keratitis, and Mooren's ulcer had a beneficial result, with resolution, reduction, or prevention of inflammation. Six patients (14%) with scleritis, ocular cicatricial pemphigoid, or endothelitis showed no clinical improvement. Two patients (5%) had significant ocular discomfort, and the drug had to be discontinued in them. None of the other patients developed local side effects. Twenty-seven of these patients were followed with serial cyclosporin A blood levels and serum creatinine. None of these patients developed measurable drug blood levels or renal toxicity.

Administration, Topical↗

Factors associated with high postoperative myopia after penetrating keratoplasties in infants.

Sixteen penetrating keratoplasties performed in patients younger than 2 years of age were reviewed to determine which factors were associated with high postoperative refractive errors. When tissue from donors younger than 2 years was used, the mean postoperative spherical equivalent was -13.7 diopters, compared with +2.0 diopters when tissue from donors older than 2 years was used (P = 0.001). Analysis of variance suggests that the use of a 0.5-mm oversized transplant, as opposed to a 0- to 0.3-mm oversized transplant, contributed to the production of high myopia when tissue from donors younger than 2 years was used (P = 0.009). The high myopia appears to have resulted from steep transplant curvatures. Based on these results, we recommend against the combined use of corneal transplant tissue from very young donors and 0.5-mm oversized transplants for infant penetrating keratoplasties.

Adolescent↗

Paraneoplastic pemphigus, cicatricial conjunctivitis, and acanthosis nigricans with pachydermatoglyphy in a patient with bronchogenic squamous cell carcinoma.

A 77-year-old man with chronic conjunctivitis, acanthosis nigricans with pachydermatoglyphy, and pemphigus-like mucocutaneous lesions was found to have a well-differentiated bronchogenic squamous cell carcinoma. Histopathologic and immunofluorescence studies confirmed the diagnosis of paraneoplastic pemphigus. Skin lesions resolved with oral prednisone and azathioprine therapy, but the conjunctivitis and mucous membrane erosions persisted. The conjunctiva later became scarred with foreshortening of the fornices and development of symblepharon. External beam irradiation arrested the growth of the tumor but did not have any effect on the diseased conjunctiva and other mucous membranes. This case demonstrates that cicatrizing conjunctivitis with bullous mucocutaneous lesions may be a clinical sign associated with an occult neoplasm.

Acanthosis Nigricans↗

Corneal disease.

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Adult↗

Lamellar corneal autograft for corneal perforation.

A corneal perforation developed in the right eye of a 46-year-old man after removal of a corneal foreign body. Two attempts to seal the perforation with cyanoacrylate glue failed. The patient subsequently underwent lamellar corneal autograft, which successfully closed the perforation. To the best of our knowledge, this is the first report of repairing a corneal perforation with lamellar corneal autograft.

Corneal Injuries↗

Cholesterol localization in ultrathin frozen sections in Schnyder's corneal crystalline dystrophy.

We examined a 57-year-old woman who had bilateral corneal crystalline deposits associated with xanthelasma. The patient's son had bilateral stromal haze. Plasma cholesterol and apolipoprotein A-I and B levels were normal. Histopathologic examination disclosed lipid deposits, particularly in the superficial stroma and Bowman's layer. These deposits stained with oil red O and filipin, a fluorescent probe that specifically detects unesterified cholesterol. Cryoultramicrotomy disclosed more specific ultrastructural localization of unesterified cholesterol with an array of crystals resembling multiple plates in extracellular corneal tissue.

Cataract↗