J Korean Ophthalmol Soc.  2010 Oct;51(10):1368-1373.

Comparison of the Effects of Patterned and Conventional Laser Photocoagulation in Branch Retinal Vein Occlusion

• Park YG
• Jee DH
• Yang JW

Abstract

PURPOSE
To compare the clinical effect and complications between patterned laser photocoagulation with short exposure time and conventional laser photocoagulation for neovascularization in branch retinal vein occlusion (BRVO).
METHODS
A prospective study was conducted on 36 patients (39 eyes) who required laser photocoagulation for neovascularization due to BRVO. The patients were divided into 2 groups, the patterned laser photocoagulation group (laser exposure time 0.02 sec, 3 x 3 array patterned photocoagulation) and conventional laser photocoagulation group (laser exposure time 0.2 sec). Other laser parameters (burn intensity and spot size) were the same. Pain score at the time of treatment was monitored after the laser photocoagulation. In addition, best-corrected visual acuity as well as central macular thickness measurements were performed before the treatment and after 2, 4, 8, and 12 weeks. The regression of neovascularization in fluorescein angiography was monitored during follow-up periods.
RESULTS
The patterned laser photocoagulation group had a greater reduction in pain during laser photocoagulation, and a decreased change in central macular thickness after laser photocoagulation than the conventional laser photocoagulation group. In particular, the patterned laser photocoagulation group had a statistically significant difference between the 2 groups at postoperative 8 and 12 weeks. The regression rate of neovascularization between the 2 groups had no statistically significant difference.
CONCLUSIONS
Patterned laser photocoagulation with a short exposure time decreases pain and postoperative macular edema with no difference in regression of neovascularization. Patterned laser photocoagulation with a short exposure time can be considered as a useful and efficient method for neovascularization in BRVO.

Keyword

Branch retinal vein occlusion; Exposure time; Patterned laser photocoagulation

MeSH Terms

Fluorescein Angiography
Follow-Up Studies
Humans
Light Coagulation
Macular Edema
Prospective Studies
Retinal Vein
Retinal Vein Occlusion
Retinaldehyde
Visual Acuity
Retinaldehyde

Figure

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  Figure 1. Changes in best-corrected visual acuity (BCVA) after laser photocoagulation in patterned group and conventional group. Preoperaive and postoperative BCVA are not statistically significantly different between the two groups (p = 0.657, 0.721, 0.215, 0.286, 0.504, repeated measure ANOVA).

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  Figure 2. Changes in central macular thickness (CMT) after laser photocoagulation in patterned group and conventional group. There is no statistically significant difference in CMT preoperatively and at postoperative 2 and 4 weeks (p = 0.790, 0.730, 0.534, repeated measures ANOVA). But there is a statistically significant difference between the two groups at post-operative 8 and 12 weeks (p = 0.013, 0.027, repeated measures ANOVA).

Reference

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