Comparison of clinical outcomes between intense pulsed light therapy using two different filters in meibomian gland dysfunction: Prospective randomized study

Abstract

Abstract Purpose Our study compared treatment efficacy between cut-off and notch filters in intense pulsed light (IPL) therapy through a prospective, randomized paired-eye trial. Additionally, under strict environment allowing only artificial tear, the efficacy of IPL treatment alone was investigated. Methods One eye was selected for an acne filter and the other for a 590 nm filter. Identical IPL treatments were applied during four regimens of IPL. Tear break up time (TBUT), Oxford scale, SICCA staining score, tear matrix metalloproteinase-9 expression, tear osmolarity, and OSDI questionnaires were evaluated before and after IPL. Meibomian gland (MG) parameters were measured. Results Regardless of filter, TBUT (1.95 ± 1.07 to 4.02 ± 1.58, p < 0.001), OSDI score (65.34 ± 20.66 to 41.34 ± 18.84, p < 0.001), upper lid meibum expressibility (3.08 ± 2.29 to 7.38 ± 1.28, p < 0.001), and lower lid meibum expressibility (2.88 ± 1.86 to 7.49 ± 1.00, p < 0.001) were markedly improved after IPL. Between acne and 590 nm filters, the former tended to show better efficacy in lower lid expressibility (4.94 ± 1.52 vs 4.36 ± 1.58, p = 0.279) and lower lid meibum secretion score (-11.6 ± 4.45 vs -10.1 ± 5.16, p = 0.271), although not statistically significant. Conclusions IPL without additional treatment is efficacious in terms of ocular surface, MG, and subjective symptoms. In addition, an acne filter may be a promising option for more MG targeted effect.