Impact Of Micropulse Transcleral Cyclophotocoagulation On The Development Of Limbal Stem Cell Deficiency In Refractory Glaucoma

primary objective  : To evaluate the impact of micropulse transscleral cyclophotocoagulation (MP-TSCPC) on the development of limbal stem cell deficiency (LSCD).

secondary objective : To characterize the pattern of changes in limbal epithelial stem cells following micropulse transscleral cyclophotocoagulation.

This is a prospective observational study conducted at Thammasat University hospital where is a referral ophthalmology center. Patients with refractory glaucoma undergoing first-time micropulse transscleral cyclophotocoagulation (MP-TSCPC) were consecutively enrolled. Participants were followed for at least 6 months with serial anterior segment OCT (AS-OCT) to assess changes in central, limbal epithelial thickness and the potential development of limbal stem cell deficiency (LSCD).

This prospective study enrolled adults with refractory glaucoma undergoing first-time micropulse transscleral cyclophotocoagulation (MP-TSCPC). Patients with pre-existing limbal stem cell deficiency (LSCD) were excluded. Baseline evaluation included BCVA, IOP, slit-lamp examination, and AS-OCT. Epithelial thickness was measured centrally and in four limbal quadrants ( superior , nasal, temporal , and inferior).Standardized MP-TSCPC (31.3% duty cycle, 2200 mW, 360 degree) was performed. Follow-up at 1, 3, and 6 months included repeat clinical examination and AS-OCT. The primary outcome was maximal limbal epithelial thickness. Changes over time were analyzed using a linear mixed-effects model and repeated  measures anova

Nineteen patients (355 observations) were analyzed using a linear mixed-effects analysis The result demonstrated no significant change in epithelial thickness over time (F=0.046, p=0.987).The estimated overall mean thickness was 62.51±1.04 µm (95% CI 60.37–64.64). Repeated-measures ANOVA (N=14) confirmed the absence of a time effect (F=0.440, p=0.726). Mauchly’s test indicated that sphericity was not violated for time (p=0.878) or location (p=0.523). No significant time–location interaction was observed (p=0.637).

Micropulse transscleral cyclophotocoagulation (MP-TSCPC) demonstrated a favorable corneal safety profile, with no significant longitudinal changes in limbal or central epithelial thickness over 6 months. These findings suggest that MP-TSCPC is not associated with structural changes consistent with limbal stem cell deficiency (LSCD) in patients with refractory glaucoma. Larger studies with extended follow-up are warranted to further establish long-term safety.