Micropulse transscleral cyclophotocoagulation (MP-TSCPC) performed with a 120-second setting can effectively lower intraocular pressure (IOP), with 45.5% success at 6 months, according to a study published in the Journal of Glaucoma. However, the study shows retreatment is “of little benefit in nonresponders or those with early failure.”
Researchers evaluated 94 eyes of 94 patients in a retrospective consecutive case series to establish the efficacy, safety, factors of success, and retreatment benefit of MP-TSCPC for medically uncontrolled mild to severe primary or secondary open-angle glaucoma. The study was conducted at the university hospital of Montpellier between May 1, 2017, and October 31, 2019. Researchers examined patients before undergoing MP-TSCPC and at week 1 and months 1, 3, and 6 after the procedure.
Early retreatment (within 6 months) was performed on 15 (16.0%) patients at a median postoperative delay of 4.4 months. The baseline mean IOP was 26.6±7.1 mm Hg and decreased to 26.5±8.2 mm Hg at month 6 (P =.5). The success rates were 100.0% (13/13), 46.7% (7/15), 45.5% (5/11), and 16.7% (1/6) at week 1 and months 1, 3 and 6, respectively.
Another 19 (20.2%) patients underwent retreatment after 6 months, defined as late retreatment, with a median delay of 10.2 months. Their baseline first-treatment mean IOP was 26.1±7.3 mm Hg and baseline second-treatment IOP was 23.0±4.9 mm Hg. Their retreatment success rate was 84.2% (16/19), 70.6% (12/17), 64.7% (11/17), and 63.6% (7/11) at week 1 and months 1, 3, and 6, respectively.
Overall, patients with early retreatment had a 6-month success rate of 16.7%, and those who underwent late retreatment had a 63.6% success rate.
Researchers also discovered that a longer axial length was associated with poorer outcomes. Mean axial length in patients whose surgery was successful was 24.1 mm, while the mean length in patients whose surgery failed was 25.5 mm (P =.05).
The investigators report the 6-month follow up time as a potential limitation of the research.
“In the subgroup with an early second procedure, the success rate at month 6 was very low, 16.7%. However, in the subgroup with a late second procedure, the success at month 6 (63.6%) was consistent and even better than after the first procedure. This observation suggests that early nonresponding patients remain nonresponding after retreatment, so we should consider retreatment only in initial responders,” the study says.
Reference
Chamard C, Bachouchi A, Daien V, Villain M. Efficacy, safety, and retreatment benefit of micropulse transscleral cyclophotocoagulation in glaucoma. J Glaucoma. 2021;30(9):781-788. doi:10.1097/IJG.0000000000001900