Aim: To evaluate the efficacy and safety of MicroPulse transscleral laser therapy (MPTLT) for cyclophotocoagulation in the treatment of glaucoma with different doses of energy.
Materials and methods: A retrospective review was done of 136 eyes in 90 patients treated with MPTLT between 2018 and 2022. Intraocular pressures (IOP) at follow-ups were compared with a paired student t-test and treatment outcomes with a Chi-squared test. The cohort was stratified into subgroups to analyze the effect of total applied energy on outcomes. The variance between energy groups was analyzed with the Kruskal–Wallis test adjusted for multiple comparisons.
Results: A total of 136 eyes of 90 patients underwent MPTLT for mostly open angle (36.0%) and childhood glaucoma (30.1%). Applied energy range was between 37.5 and 195.6 J with a mean [standard deviation (SD)] of 100.7 (34.3) J. Applied energy of 125–200 J reduced IOP the most at 2 years with 90% of eyes within 6–21 mm Hg and 66% of eyes having IOP reduced at least 20% (p < 0.001) from baseline. However, at 2 years, energy 50–75 J achieved fewer eyes with two or more Snellen lines lost than energy 125–200 J and a lower proportion of eyes with at least one symptom (p < 0.05). No severe complications of hypotony, phthisis bulbi, or chronic inflammation were reported.
Conclusion: IOP reduction and safety outcome of MPTLT varied with applied energy. Doses should be adjusted to target the treatment goals for individual patients.
Clinical significance: MPTLT was found to be effective in lowering IOP in glaucoma. Using high levels of energy is associated with higher rates of complications.
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