D Rosberger | PubMed Health

PubMed1998

A new chart for planning retinal surgery.

PURPOSE: To design a chart for drawing retinal detachments that minimizes the circumferential distortion that occurs with the current chart. METHODS: After trying several standard map projections, a hybrid chart was created. It retains the radial equidistant projection of the current chart from the posterior pole to the equator, but superimposes stereographic projection anterior to the equator. The hybrid chart was put on trial for drawing retinal lesions and planning retinal detachment surgery at the New York Hospital and at the University Eye Clinic in Tübingen in May 1992. RESULTS: The stereographic projection anterior to the equator has minimized the distortion of retinal breaks and other pathology in the anterior retina when drawn on the chart. Retinal breaks can be drawn as they are seen ophthalmoscopically and estimates of their real dimensions derived from the chart. CONCLUSION: A new retinal chart that minimizes circumferential distortion anterior to the equator has proven advantages for planning retinal detachment surgery.

Humans↗

PubMed1991

Ultrasonic tissue characterization of uveal melanoma and prediction of patient survival after enucleation and brachytherapy.

We performed survival studies on 136 patients with uveal malignant melanoma who were examined with ultrasonic tissue characterization before treatment with cobalt-60 brachytherapy (74 patients) or enucleation (62 patients). Mean follow-up time was 58.7 months for the brachytherapy group and 59.0 months for the enucleated group. The maximal follow-up time was nearly ten years. Univariate survival analysis showed that patients with small tumors (less than 250 mm3, 49 patients) had a higher five-year survival when treated with brachytherapy than when treated with enucleation. No patients in this study with tumor volumes greater than 1,500 mm3 (13 patients) were treated with brachytherapy. For tumors of intermediate size (74 patients), survival analysis did not indicate appreciable differences between the treatment options. However, multivariate models including two ultrasonic tissue characterization variables, scatterer size and concentration, showed appreciable intergroup differences in the dependence of survival on these factors. Results suggest that tissue properties detectable with ultrasonic techniques are related to differences in patient survival and may be used for treatment planning for tumors of intermediate size.

Brachytherapy↗