Cyclophotocoagulation and cyclocryocoagulation as primary surgical procedures for open-angle glaucoma

Comparative study of cyclophotocoagulation (CPC) and cyclocryocoagulation (CCT) as primary surgical procedures in patients with open-angle glaucoma with regard to efficacy and complications.

In this retrospective cohort study, 184 eyes of 112 patients in whom cyclodestructive surgery was performed as a primary surgical procedure were examined. CPC was performed on 133 eyes and CCT on 51 eyes. A standardised multiple measurement of intraocular pressure (IOP) was performed on all patients preoperatively and at the follow-up examination after an average of 5.5 (1.5–12) months. In addition, the best-corrected visual acuity and the number of antiglaucoma agents were recorded.

On average, a reduction in IOP was observed after both of the cyclodestructive procedures (CPC: −1.55 ± 2.50 mmHg, p < 0.05; CCT: −2.33 ± 3.06 mmHg; p < 0.05). The average difference in IOP reduction between the two procedures (0.78 mmHg) proved to be statistically insignificant (p = 0.08). In contrast, greater patient age and higher preoperative IOP values were found to be highly significant influencing factors. In 45 % and 70 % of the patients treated with CPC and CCT, respectively, IOP was reduced by at least 20 %, with no increase in medication or with a reduction in medication of at least one substance with no increase in pressure. CPC and CCT produced an average loss of visual acuity of more than two lines in 10.5 % and 9.8 % of cases, respectively. Permanent hypotension did not occur in any of the cases.

A moderate reduction in IOP is achievable with both procedures, with CCT tending to produce a greater reduction in pressure. The efficacy of primary cyclodestructive procedures increases with increasing patient age and with higher preoperative IOP values. The risk of serious complications can be considered low.