Assessment of Meibomian Gland (MD) Impairment Among Seasonal Allergic Conjunctivitis (SAC) Patients.

BACKGROUND Allergic conjunctivitis, one of the frequently occurring ocular surface diseases, can cause mucus discharge, itchy sensation, conjunctival hyperemia, and papillary formation. Seasonal allergic conjunctivitis (SAC) is associated with xerophthalmia and instability of tear film. Meibomian gland (MG) can secrete lipids to avoid xerophthalmia. However, there have been few reports on MG morphological alterations of SAC patients. This study aimed to examine the morphological alterations of MG among SAC patients. MATERIAL AND METHODS Our study included 89 eyes from 89 patients with SAC and 112 eyes of healthy volunteers. The symptoms were assessed by ocular surface disease index (OSDI) questionnaire. Then, the tests shown below were carried out, including tear evaporation rate from the ocular surface (TEROS), slit-lamp examination, break-up time (BUT) of tear film, Schirmer test I, vital staining, meibography, and meibum expression grading. MG was examined with laser scanning confocal microscopy (LSCM). RESULTS Relative to the control group, the OSDI was significantly higher in the SAC group. TEROS values, BUT, vital staining, MG expression, MG distortion rates, and MG dropout grades were significantly worse in the SAC group compared with the control group. As suggested by LSCM, SAC patients had markedly worse averages of parameters compared with controls. CONCLUSIONS The patients with SAC have more significant morphological and cytological changes in the MG. The Keratograph 5M system and LSCM are effective methods for evaluating MG status and ocular surface diseases.