The effect of the surgeon and the laser wavelength on the response to focal photocoagulation for diabetic macular edema.

OBJECTIVE

To determine the effect of the surgeon and the wavelength of laser used on the response to focal photocoagulation for diabetic macular edema.

DESIGN

Retrospective case-control study.

PARTICIPANTS

Forty-four matched pairs of cases by two different retina surgeons in the study of surgeon influence were examined. Sixty-nine matched pairs of cases using dye yellow versus argon green laser treatment in the study of wavelength influence also were studied. In both studies, eyes were matched for the only patient-dependent variables affecting outcome: age, initial visual acuity, follow-up time, and diabetic control by diet versus any other method.

INTERVENTION

Focal laser photocoagulation for clinically significant diabetic macular edema was performed.

MAIN OUTCOME MEASURE

Visual acuity at 6 months follow-up was measured.

RESULTS

For the study in which the only difference was the surgeon, at 6 months follow-up the mean difference in logarithm of the minimum angle of resolution (logMAR) visual acuity was -0.045, 95% confidence interval (-0.160, 0.070). For the study in which wavelength varied, at 6 months the mean difference in logMAR visual acuity was -0.048, 95% confidence interval (-0.147, 0.052). The power of the surgeon study to detect a difference in the logMAR visual acuity of 0.3 is 88% and of the wavelength study to detect this difference is 99%.

CONCLUSION

In looking at the 6-month visual outcome after focal laser photocoagulation for clinically significant diabetic macular edema, different fellowship trained surgeons and the choice of green or yellow wavelength had no effect on the treatment outcome.