Effect of a single vectored thermal pulsation treatment of Meibomian gland dysfunction patients under controlled environmental conditions

Abstract

To assess the prophylactic effect of LipiFlow treatment in Meibomian gland dysfunction (MGD) patients exposed to an adverse environmental humidity. MGD patients were exposed to normal (23 °C; 50% relative humidity; 30 min) and adverse (23 °C; 10% relative humidity; 2 h) controlled environments consecutively during baseline and follow-up visits (3, 6, and 12 months) after a single LipiFlow treatment. Ocular Surface Disease Index (OSDI), lipid layer thickness (LLT), fluorescein tear break-up time (TBUT), corneal and conjunctival staining, change in dry eye symptoms questionnaire (CDES-Q), and Meibomian gland yielding liquid secretion (MGYLS), were assessed. Linear mixed-effects and cumulative logit mixed models were fitted to assess the effect of the LipiFlow treatment over time and within the controlled environments. Seventeen females and 4 males (59.6 ± 9.4 years) completed the study. LLT and TBUT did not vary significantly (p > 0.05) after LipiFlow treatment. OSDI, corneal and conjunctival staining, and MGYLS scores were improved (p ≤ 0.01) 12 months after treatment. After the adverse exposure, corneal staining increased at all visits (p = 0.01), and there was no significant improvement in CDES-Q scores after LipiFlow treatment (p ≥ 0.07). One LipiFlow treatment improved objective and subjective outcomes in MGD disease for at least one year. Further studies are needed to support that LipiFlow might also help as an adjuvant to avoid acute flares against an adverse environmental humidity.

Figure 1

Chronological scheme of the tests performed at each visit. OSDI = ocular surface disease index, BCVA = best corrected visual acuity, MGYLS = meibomian gland yielding liquid secretion, LLT = lipid layer thickness, TBUT = tear break-up time, MG = Meibomian glands, CDES-Q = change in dry eye symptoms questionnaire.

Figure 2

Fluorescein corneal staining. Scores based on the Cornea and Contact Lens Research Unit (CCLRU) scale were determined at baseline and at the 3-, 6-, and 12-month follow-up visits, before and after the exposure to the adverse controlled environment. Mean values and confidence interval error bars are represented. Grey bars represent comparisons between visits during exposure to the normal environment. *p = 0.0314, **p = 0.0001, ***p < 0.0001. The adverse environmental exposure had a significant (p = 0.0165) negative effect on corneal staining regardless of the visit. The interaction between the effect of the time and the conditions was not significant (p = 0.49).