advertisement

Editors Selection IGR 10-4

Surgery: Transillumination for cyclodestruction

Comment by Jeffrey Kammer on:

22461 Ciliary body position variability in glaucoma patients assessed by scleral transillumination, Agrawal P; Martin KR, Eye, 2008; 22: 1499-1503

Find related abstracts

The standard technique for performing requires positioning the G-probe footplate at the limbus, thereby centering the fiber optic tip 1.2 mm from the corneosceral junction. Based on histopathology studies, this places the laseremitting fiber in optimal position to ablate the ciliary processes. Agrawal and Martin (1328) presented the results of their retrospective nonrandomized consecutive case series, suggesting that scleral transillumination should be routinely used to more precisely guide the placement of the contact probe during cyclodestructive procedures. These investigators selected 100 consecutive glaucoma patients and subjected them to a standardized protocol for scleral transillumination. They found that the mean position of the anterior border of the ciliary body was 2.98 ± 0.36 mm from the limbus, with high correlation between the two eyes. The study did not find any significant difference in ciliary body position in any individual quadrant between phakic and pseudophakic/aphakic eyes. One particularly significant finding was that the ciliary body was consistently located more posterior in the superior and inferior quadrants as compared to either horizontal quadrant. The pattern of ciliary body localization is similar to that seen in a histological assessment of the ciliary body (Prost, Ophthalmologica 1984; 188: 9-13), but the absolute values were different. Based on these findings, the authors posit that G-probe placement 1.2 mm posterior to the limbus is likely adequate in the horizontal quadrants, but 'may' need to be moved more posterior in the vertical quadrants. The study provides compelling data on ciliary body position in glaucomatous eyes, but it does not provide any concrete recommendations on how this can be translated to clinical practice. The authors acknowledge that a prospective randomized study comparing therapeutic outcomes of diode cyclophotocoagulation using traditional placement parameters compared with titrated probe positioning, would provide more compelling evidence regarding the value of scleral transillumination.

• ← Previous
• Next →