Biomedical subjects
Publications and source records attributed to C C Barr.
An 84-year-old man had a verrucous lesion of the left lower eyelid that caused progressive ectropion. Cultures of the lesion taken at the time of surgical excision demonstrated Blastomyces dermatitidis. Histologically, the excised tissue demonstrated pseudoepitheliomatous hyperplasia, a characteristic change of cutaneous blastomycosis.
Preretinal neovascularization in response to retinal vascular occlusions developed in two patients receiving treatment for systemic lupus erythematosus. In both patients, the preretinal neovascularization was asymptomatic and was discovered on routine ocular examination. One patient required bilateral peripheral ablative argon-laser therapy for florid preretinal neovascularization. This patient had severe occlusive retinal vasculitis despite serologic evidence of remission of the underlying disease process.
I measured the area of the retina in ten autopsy eyes and the area of 500 mu argon laser burns placed with both Goldmann and Rodenstock contact lenses in two eyes that were subsequently enucleated. The mean area of the retina available for panretinal photocoagulation is 1,050 mm2. The mean diameter of 500 mu argon laser burns is 490 mu when placed with a Goldmann contact lens and 810 mu when placed with a Rodenstock contact lens. The maximum number of 500 mu burns that can be used to treat the entire extramacular retina in the normal sized eye is approximately 5,500 when a Goldmann contact lens is used, and approximately 2,050 when a Rodenstock contact lens is used.
Two patients with presumed ocular histoplasmosis syndrome developed optic disc edema. In both cases the edema resolved without residual impairment of visual function. Although peripapillary changes in ocular histoplasmosis are common, optic disc edema is rare. The pathogenesis of the edema is unknown.
Of 122 patients with corneoscleral lacerations repaired during a four-year period, 21 (17%) underwent enucleation primarily or within ten days of injury, 85 (70%) had at least six months of follow-up, and 16 (13%) were unavailable for follow-up. The most significant predictors of enucleation were poor initial visual acuity, the amount of hyphema, the presence of posterior uveal prolapse or vitreous hemorrhage, the extent of lens damage, and the length of laceration. The most significant predictors of a good visual outcome were good initial visual acuity, absence of hyphema, absence of posterior uveal prolapse or vitreous hemorrhage, and length of laceration. Final astigmatism was greater if the corneal wound was 4 mm or longer. Delaying the initial repair up to 36 hours had no effect on outcome.
A 40-year-old man had a small choroidal melanoma in his left eye. The tumor was seemingly erradicated by xenon arc photocoagulation; however, eight years later the tumor recurred along the inferior edge of the chorioretinal scar, and the eye was enucleated. Histopathologic examination of the lesion revealed a spindle B-cell melanoma.
A 58-year-old man sustained a penetrating injury in the left eye from a nylon cord fragment from an electric rotary weed trimmer. Repair of the corneal laceration, foreign body extraction, and anterior vitrectomy were performed. One year post injury the visual acuity was stable at 6/60. The need for protective eyewear when using power tools is emphasized.
Four cases of the simultaneous occurrence of bilateral diffuse melanocytic uveal tumors were studied by us. In each case, the patient had an associated systemic malignant neoplasm diagnosed by biopsy or at autopsy. There was no evidence of metastatic melanoma in any patient. Clinically, the patients experienced rapid loss of vision, and cataracts were usually present. Multiple pigmented and nonpigmented placoid iridic and choroidal nodules, as well as serous retinal detachment, frequently were noted. Histopathologically, the uveal tracts of both eyes were diffusely infiltrated by preponderantly benign-appearing nevoid or spindle-shaped cells. Areas of necrosis within the tumors and scleral involvement were commonly seen. We believe this constellation of findings constitutes a new syndrome in which there is a bilateral, diffuse proliferation of melanocytic cells throughout the uvea in association with a systemic malignant neoplasm.
Idiopathic epiretinal membranes were observed in six patients, all under 35 years of age. The clinical features were similar to those of idiopathic epiretinal membranes seen in older age groups. The center of the membrane was located over a large retinal vessel in five of the patients. Follow-up periods, mostly without surgery, ranged from four months to nine years. Fluctuating levels of vision were observed, but the vision eventually improved in three patients, and remained stable in two others. In one patient the vision worsened, and vitreous surgery was used to remove the epiretinal membrane, resulting in improved vision.
Five-year survival data were available in 78 cases originally classified as uveal melanomas in patients less than 20 years old. Forty-two were malignant melanomas arising from the choroid and/or ciliary body; 13 patients from this group died of metastatic disease. Factors that significantly correlated with fatality were a red, painful eye, extraocular extension at enucleation, basal tumor diameter greater than 10 mm, increased mitotic activity, and tumor necrosis. There were 36 iridic tumors; nine were reclassified as nevi. Of the 27 patients with iridic melanomas, only four died of metastases. The predominant factors relating to fatal outcome were glaucoma, extension of tumor into the ciliary body, diffuse growth, deep angle invasion, scleral invasion by tumor cells, and increased mitotic activity. Except for their relative rarity, uveal melanomas in children and adolescents did not differ significantly from their counter-parts in adults.
A 59-year-old black female with rheumatoid arthritis developed diffuse anterior scleritis with orbital and adnexal involvement. Computerized axial tomograhy (CAT) demonstrated the location and extent of the lesion. Biopsy of subconjunctival tissue revealed a rheumatoid nodule, characterized by granulomatous inflammation and fibrinoid necrosis. The patient improved rapidly on large doses of systemic corticosteroids. The relationship of scleritis to rheumatoid arthritis is discussed. The histopathologic features of rheumatoid scleritis, its apppearance on the CAT scan, and the management of this disease are also presented.
Two patients had multiple, fine, polychromatic corneal crystals on ocular examination. Peripheral corneal biopsies and electron microscopic studies demonstrated that the crystals, which were located solely within the cytoplasm of keratocytes, exhibited an internal periodicity of 10 nm and developed within dilated cisternae of rough-surfaced endoplasmic reticulum. Histochemical studies of the corneal crystals confirmed their proteinaceous nature (immunoglobulin crystals). Serum protein analysis showed that both patients had a monoclonal gammopathy with an elevated IgG level and increased K light chains. The associated proteinopathy was unsuspected in both patients until the nature of the crystals was established. Both patients had a neoplastic process; one had a previous diagnosis of Hodgkin's disease, and multiple myeloma developed in the other on follow-up studies. Clinicians should be aware of the possibility of a malignant disorder in patients with corneal crystal-line deposits.
Acute disc swelling was documented in 21 eyes of 12 patients with long-standing juvenile diabetes. All but one patient were in the second or third decade of life, with a 13-year average duration of diabetes. Seventeen eyes had initial acuity of 20/50 or better, including nine eyes with 20/25 or better; disc swelling was asymptomatic in six eyes. Simultaneous bilateral disc swelling occurred in seven patients. With no specific therapy, vision generally recovered to normal levels within a few weeks, but a few patients retained arcuate, nerve fiber bundle, field defects and optic atrophy. There was no positive correlation with the degree of diabetic retinopathy, and disc swelling did not seem to be a harbinger of progressive retinopathy or proliferation at the nerve head. Disc swelling in juvenile diabetics represents a distinct clinical entity that must be distinguished from other causes of acquired nerve head elevation, especially papilledema of increased intracranial pressure.
A 13-year-old boy had mild vitreous hemorrhage in the left eye, and a red angioma-like epiretinal mass in the equatorial zone of the temporal fundus. The retina anterior to the mass was nonvascularized, and similar nonvascularization of the pre-equatorial retina was present in the temporal quadrants of the fellow eye. Fluorescein angiography showed intraretinal neovascularization along the margin of the perfused and nonperfused retina and leakage from portions of the angioma-like mass, suggesting that it was composed of neovascular tissue and adjacent hemorrhage. The patient had been a premature infant, with a birth weight of 1,092 g, supporting the presumptive diagnosis of previously asymptomatic retrolental fibroplasia. Photocoagulation was successful in obliterating the neovascular tissue.
We reviewed 38 cases of small choroidal melanomas on file in the Eye Pathology Laboratory of Bascom Palmer Eye Institute, Miami. Clinical and histopathological features of these cases were noted, and clinical follow-up information was obtained for 36 (95%) of the patients. Two tumor deaths occurred among the 18 patients that had a possible follow-up period of six years of more, yielding a tumor death rate of 11%. Retrospective analysis of clinical records and photographs permitted us to correlate the presence or absence of documented tumor growth with the degree of mitotic activity.
Standard radiographic techniques are often inadequate in demonstrating the presence and location of intraocular foreign bodies. Computerized axial tomography was used to confirm the presence of a metallic foreign body in a patient with heterochromia iridis and suspected ocular siderosis in whom no foreign material was found by conventional examination methods.
Medical practitioners often have difficulty in assessing the presence or severity of diabetic retinopathy. The tourniquet test is a method of assessing diabetic capillary fragility that has been felt to reliably correlate with background and proliferative diabetic retinopathy. We studied 100 consecutive diabetic patients and 50 age-matched controls in a masked fashion, using fundus photographs and fluorescein angiography to correlate the amount of capillary fragility with the presence and severity of background and proliferative diabetic retinopathy. Although the severity of diabetic capillary fragility did correlate with the presence and severity of diabetic retinopathy (p less than 0.001), this test was not as good an indicator of diabetic retinopathy as were other risk factors such as duration of diabetes (p much less than 0.001). The tourniquet test is unreliable in predicting the presence or severity of diabetic retinopathy because of its high false negative response rate.