Evaluation of contact versus non-contact diode laser cyclophotocoagulation for refractory glaucomas using similar energy settings.

Purpose: To compare the efficacy of contact and non-contact techniques of diode transscleral cyclophotocoagulation (TSCPC) in patients with refractory glaucoma in a prospective randomized manner.

Methods: Sixty eyes with refractory glaucoma were randomly treated with either the contact or non-contact technique of diode TSCPC and followed up for a minimum of 12 months. A standard protocol of 1500 mW for 2 s per spot, with 40 spots over the entire 360 degrees circumference was followed for all eyes in both groups.

Results: The reduction of mean baseline intraocular pressure (IOP) from 44.5 +/- 7.4 mmHg to 14.8 +/- 1.8 mmHg with the contact mode was not significantly different from that in the non-contact mode of 41.9 +/- 8.8 mmHg reduced to 14.5 +/- 1.5 mmHg (P = 0.34). The probability of IOP survival (<22 mmHg) at 1 year using the Kaplan-Meier plot was better using the contact mode, although the results did not achieve statistical significance. However, the average repeat treatments per eye with the non-contact mode (1.6 +/- 0.7) was significantly higher than with the contact method (1.2 +/- 0.6; P < 0.05).

Conclusion: Using an energy setting of 3 J per spot, both the contact and non-contact methods of laser delivery were found to be equally effective in lowering IOP in eyes with refractory glaucoma.