PubMed Health⌕ Search

Biomedical subjects

J Augsburger

Publications and source records attributed to J Augsburger.

9 recordsLinked to original sources

A proposed simple method for measurement in the anterior chamber angle: biometric gonioscopy.

OBJECTIVE: To design a system of gonioscopy that will allow greater interobserver reliability and more clearly defined screening cutoffs for angle closure than current systems while being simple to teach and technologically appropriate for use in rural Asia, where the prevalence of angle-closure glaucoma is highest. DESIGN: Clinic-based validation and interobserver reliability trial. PARTICIPANTS: Study 1: 21 patients 18 years of age and older recruited from a university-based specialty glaucoma clinic; study 2: 32 patients 18 years of age and older recruited from the same clinic. INTERVENTION: In study 1, all participants underwent conventional gonioscopy by an experienced observer (GLS) using the Spaeth system and in the same eye also underwent Scheimpflug photography, ultrasonographic measurement of anterior chamber depth and axial length, automatic refraction, and biometric gonioscopy with measurement of the distance from iris insertion to Schwalbe's line using a reticule based in the slit-lamp ocular. In study 2, all participants underwent both conventional gonioscopy and biometric gonioscopy by an experienced gonioscopist (NGC) and a medical student with no previous training in gonioscopy (JK). MAIN OUTCOME MEASURES: Study 1: The association between biometric gonioscopy and conventional gonioscopy, Scheimpflug photography, and other factors known to correlate with the configuration of the angle. Study 2: Interobserver agreement using biometric gonioscopy compared to that obtained with conventional gonioscopy. RESULTS: In study 1, there was an independent, monotonic, statistically significant relationship between biometric gonioscopy and both Spaeth angle (P = 0.001, t test) and Spaeth insertion (P = 0.008, t test) grades. Biometric gonioscopy correctly identified six of six patients with occludable angles according to Spaeth criteria. Biometric gonioscopic grade was also significantly associated with the anterior chamber angle as measured by Scheimpflug photography (P = 0.005, t test). In study 2, the intraclass correlation coefficient between graders for biometric gonioscopy (0.97) was higher than for Spaeth angle grade (0.72) or Spaeth insertion grade (0.84). CONCLUSION: Biometric gonioscopy correlates well with other measures of the anterior chamber angle, shows a higher degree of interobserver reliability than conventional gonioscopy, and can readily be learned by an inexperienced observer.

Adult↗

External radiotherapy in macular degeneration: technique and preliminary subjective response.

PURPOSE: This study attempted to assess the toxicity and possible preliminary benefits from the administration of low-dose external beam irradiation for age-related macular degeneration (ARMD). The premise of the treatment is that radiation induces regression and/or promotes inactivation of the subretinal neovasculature which would result in reabsorption of fluid and blood. This would reduce the risk for further leakage or bleeding, as well as subretinal fibrosis. Consequently, the beneficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet ARMD with the possibility for slight improvement. METHODS AND MATERIALS: Allegheny University Department of Radiation Oncology treated 41 patients prospectively from January through October 1995 with low-dose irradiation for wet-type macular degeneration. A total of 39 patients were treated with a total dose of 14.4 Gy in eight fractions of 1.8 Gy/fraction over 10-13 elapsed days. The first two patients were treated with a total dose of 10 Gy in five fractions of 2 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. Some of the patients (36.7%) had laser treatments in the study eye: 21.9% (9) once, 5% (2) twice, 9.7% (4) thrice or more. Subjective visual acuity and toxicity data were collected on all patients. RESULTS: At 2-3 weeks after treatment 29 patients (70%) retained their visual acuity without change, 10 (24.5%) stated they had improved vision, and 2 (4.8%) stated their vision continued to decrease. At 2-3 months after treatment, 27 patients (65.8%) had no change in their vision, 11 (27%) had an improvement in their vision, and 3 (7.2%) had a decrease in visual acuity. Six patients of 41 in the treated group had acute transient side effects. CONCLUSION: Our observations in this group of 41 patients support the conclusion that many patients will have improved or stable vision after treatment with low-dose irradiation for age-related wet-type macular degeneration.

Adult↗

125I plaque therapy for uveal melanoma. Analysis of the impact of time and dose factors on local control.

BACKGROUND: 125I episcleral plaque therapy has gained wide acceptance for the treatment of uveal melanoma because of its potential to preserve vision, salvage the globe, and provide good local control. A rigorous analysis of the optimum radiation dose, dose rate, and overall treatment time has not been reported with this technique. METHODS: One hundred fifty patients with uveal melanoma treated with 125I plaques between 1982 and 1990 and included in the uveal melanoma study (UMS) database of the Wills Eye Hospital were analyzed. Mean patient age was 60.7 years (range: 17.7-84.6 years). Initial mean tumor size was 9.7 x 8.5 x 3.7 mm with a range of 4.5 to 21.5 mm in basal dimension and 1.2 to 11.8 mm in height. Mean dose to the tumor apex was 94.77 gray (Gy) (29.5-141 Gy). Mean dose rate to the tumor apex was 92.9 cGy/hr (10-292 cGy/hr); the mean dose to the base was 359 Gy (181-692 Gy); the mean dose rate to the base was 348 cGy/hr (112-893 cGy/hr); and mean duration of treatment was 124.7 hours (range: 28-333 hours) RESULTS: With a median follow-up of 68 months, there have been 33 local failures. Mean time to local failure was 19 months (range: 6-78 months). Actuarial local control is 81% at 5 years. Multivariate analysis demonstrates significant correlation of local failure with larger tumor dimension (P = 0.0046), close proximity to the optic disc (P = 0.0029), lower radiation dose to the tumor apex (P = 0.03), lower radiation dose rate to the tumor apex and base (P = 0.01 and 0.03), and longer overall treatment time (P = < 0.0001). CONCLUSIONS: This retrospective analysis reinforces the importance of dose rate, minimum tumor dose, overall treatment time, maximum tumor basal dimension, and proximity to the optic nerve in the treatment of uveal melanoma.

Adolescent↗

Radiotherapy of retinoblastoma. A review of 63 children treated with different irradiation techniques.

This is a retrospective review of treatment results in 63 children with retinoblastoma (RB) who received therapeutic irradiation from January 1975 to June 1988. Patient ages ranged from birth to 5 years with a mean age of 12.5 months. Three treatment groups were identified. In Group A, episcleral plaque was the only irradiation modality. In this group, 24 patients and 25 eyes with tumors of Reese-Ellsworth Stages I to III, and selected Stage VB tumors were irradiated using eye plaques. Twenty-two of 25 (88%) eyes are without evidence of disease (NED), and all patients are alive. Two eyes were enucleated for recurrent RB. Two of 23 eyes developed minimal cataracts. In Group B, external-beam was the only irradiation modality. Twelve patients with 21 involved eyes comprise this group. Thirteen eyes received EBRT alone. Seventy-seven percent of 13 eyes have NED. Four eyes developed cataracts. Three of 13 eyes required enucleation for progression of disease; one of these was Stage IVA and two of them were Stage VA. For Group C, external-beam plus episcleral plaque was used. Twenty-seven patients and 51 eyes with advanced retinoblastoma were included in this group. Episcleral plaque was used in 29 eyes as a salvage procedure for recurrent RB, or in selected cases was used as a boost after initial external beam irradiation. Fifteen of 29 eyes (52%) remain with NED with useful vision, and nine developed cataracts. Enucleation was performed in 14 eyes for recurrent RB. The authors conclude that radiation therapy has a major role in the management of RB due to its ability to control even advanced disease, allowing preservation of vision in a significant number of patients.

Cataract↗

Case-control study of female hormones and eye melanoma.

In a case-control study, we compared 238 women with intraocular malignant melanoma to 223 matched controls with detached retinas to evaluate the influence of hormonal factors on the risk of this cancer. We observed increased risk among women who had ever been pregnant (relative risk, 1.4; 95% confidence interval, 0.8, 2.2) and women who used replacement estrogens (relative risk, 2.0; 95% confidence interval, 1.2, 3.1), decreased risk among women who had undergone oophorectomy (relative risk, 0.6; 95% confidence interval, 0.4, 1.0), and no change in risk among women who had used oral contraceptives. Compared to hormonal effects on risk of reproductive tumors, these effects were weaker and less consistent, suggesting that hormonal factors may play only a limited role in causing melanomas of the eye.

Adult↗

Sunlight exposure as risk factor for intraocular malignant melanoma.

In a case-control study, we compared 444 patients with intraocular malignant melanoma with matched controls to evaluate the role of exposure to ultraviolet radiation and other risk factors in the pathogenesis of this tumor. Persons born in the southern United States had a relative risk of 2.7 (95 per cent confidence interval, 1.3 to 5.9) as compared with those born in the North. Subjects with brown eyes were protected as compared with those with blue eyes (relative risk, 0.6; 95 per cent confidence interval, 0.4 to 0.8), but complexion and hair color were not important risk factors. Patients with intraocular malignant melanoma were also more likely to have spent time outdoors in their gardens, to have sunbathed, and to have used sunlamps. Rarely wearing hats, visors, or sunglasses while in the sun was a risk factor for the disease (relative risk, 1.9; 95 per cent confidence interval, 1.6 to 2.2). These data suggest that sunlight exposure is an important risk factor for intraocular melanoma.

Eyeglasses↗

Combined hamartoma of the retina and retinal pigment epithelium in a patient with neurofibromatosis type 2.

We describe a young patient with combined hamartoma of the retina and retinal pigment epithelium who developed bilateral acoustic neuromas and meningiomas of the cervical-medullary junction and fifth cranial nerve. This case illustrates the association between combined hamartoma of the retina and retinal pigment epithelium and neurofibromatosis type 2. The authors recommend that children with a combined hamartoma of the retina and retinal pigment epithelium be screened for neurofibromatosis type 2.

Fluorescein Angiography↗