The effect of Intense Pulsed Light therapy on eyelid bacterial load in contact lens discomfort

To evaluate the effect of Intense pulsed light (IPL) therapy on eyelid microbiota in symptomatic contact lens (CL) wearers.

This was a prospective, randomised, double masked clinical trial. Participants with Contact Lens Dry Eye Questionnaire (CLDEQ-8) score ≥ 12 were enrolled and received two IPL/sham treatments at three-week intervals. The sham group underwent simulated light exposure using a torch while the IPL device remained inactive. Meibomian gland expression was performed for both groups after each session. Eyelid margin swabs (right eye only) were collected at baseline (day 0), after two treatment sessions (day 42), and at the final visit (day 90).

Eighteen CL wearers completed the study (IPL: n = 10; 90% female, aged 35.3 ± 13.2 years; sham: n = 8; 50% female, aged 28.9 ± 6.3 years). The IPL group demonstrated a significant reduction in bacterial load (colony forming units (CFU)/swab) from day 0 to day 42 for total gram-positive cocci (174.0 ± 11.5 to 122.0 ± 8.4; p < 0.001), total gram-positive rods (174.0 ± 8.2 to 126.0 ± 8.2; p < 0.001), coagulase-negative staphylococci (174.0 ± 12.2 to 122.0 ± 10.0; p < 0.001), and Bacillus spp. 172.0 ± 8.2 to 122.0 ± 9.9; p < 0.001). However, by day 90, bacterial count had increased relative to day 42 and was partially rebounded towards baseline numbers. The sham group showed no significant changes in bacterial load at any follow-up time point.

IPL therapy significantly reduced eyelid bacterial load after two treatment sessions in symptomatic CL wearers. However, this antimicrobial effect diminished by day 90, suggesting that sustained microbiological benefit may require optimized IPL treatment protocols.