Abstract:
This study aimed to study the clinical effects and safety in terms of symptoms and signs and to evaluate the change in tear inflammatory cytokines in meibomian gland dysfunction (MGD) after 3 sessions of Intense Pulsed Light (IPL) in a prospective randomized double-masked sham-controlled clinical trial. Patients with MGD who met all criteria were randomly assigned into IPL and sham-IPL group. The stratified blocked randomization was done using the MGD gradeas a stratum by computer-generated assistance. Each patient in IPL group underwent 3 sessions of IPL on day 0, 15 and 45. The other group underwent sham-IPL. Both group received conventional treatment as warm compression, lid scrub and artificial tears. Primary outcome was tear film break-up time. Other clinical parameters included Ocular Surface Disease Index (OSDI), symptoms of dry eyes in visual analog scale score (VAS), tear film lipid layer thickness, meibography grade, ocular surface staining using NEI grading system, meibomian gland expressibility, meibum quality, tear osmoloarity, Schirmer's test and tear cytokines (IL-1Ra and IL-6). The parameters were evaluated on day 0, 15, 45, month 3 and 6. Subgroup analysis according to stage and patient's compliance to conventional treatment were analyzed. One hundred and fourteen patients were randomized and allocated into IPL and sham-IPL group. The tear film break-up time in IPL group was significantly more than that in sham-IPL group in all visits, in any stages and in any kinds of compliance (p<0.001). The tear film break-up time increased at day 15, reached its maximum at day 45 and persisted at least six months. The meibum quality score and meibum expressibility in IPL group was significantly better than that in sham-IPL group in all visits (p<0.001). Patients who were not strictly complied with the warm compression and lid scrub could have their meibum qualities and expressibilities improved by IPL. Ocular surface staining and meibography grade in IPL group significantly improved more than that in sham-IPL group in stage 4 (p<0.05). However, tear osmolarity, Schirmer’s test, IL-1Ra and IL-6 levels were not statistically different between two groups. No adverse event occurred in IPL group. In conclusion, our study suggests that IPL is effective and safe to manage patients with meibomian gland dysfunction especially in stage 4 of the disease.
