Obstructive meibomian gland dysfunction (OMGD) is due to the meibomian gland duct obstruction and/or meibum abnormal secretion.Meibomian gland morphological change is important to clinical observation.

This study aimed to image the meibomian gland structures and the morphological changes in eyes with OMGD using a non-contact infrared meibography system (Keratograph 5M).

A case-control study was performed in Tianjin Medical University Eye Hospital from January to June in 2015.Sixty OMGD patients and 60 age-matched healthy controls were recruited.Ocular Surface Disease Index (OSDI) questionnaire was employed for the assess of ocular surface symptoms, and slit-lamp examination was performed for the observation of lid margin and meibomian gland orifices.Meibomian gland secretion scores and Keratograph 5M examination the morphological changes of the meibomian glands.According to OSDI questionnaire, the patients of OMGD were classified into mild group (12.0<OSDI≤22.0)(23 eyes), moderate group (22.0<OSDI≤32.0)(21 eyes) and severe group (32.0<OSDI≤100.0)(16 eyes). Partial or complete loss of the meibomian glands (meibomian dropout) was scored from grade 0 (no loss) through out grade 3 (lost area was >2/3 of the total meibomian gland area). Written informed consent was obtained from all subjects before the examination.

The OSDI, meibomian gland orifices, meibomian gland secretion scores and meibomian gland dropout scores were significantly higher, and BUT was dramatically shorter in the OMGD group than those in the normal group, showing significant differences between the two groups (Z=-9.425, -8.954, -7.781, all at P<0.05). The BUT was (6.10±1.91)s and (10.67±2.11)s, and meibomian gland dropout scores were 1.35±0.90 and 0.88±0.64 in the OMGD group and normal control group, showing significant differences between the two groups (t=3.276, -12.418, both at P<0.05). OSDI, meibomian gland secretion scores and meibomian gland dropout scores were significantly in three intergroups (H=52.121, 13.642, 37.180, all at P<0.05). BUT, meibomian gland orifices were significantly different among the mild, moderate and severe OMGD (F=58.191, 8.474, both at P<0.05). OSDI showed a significantly high positive correlation with meibomian gland orifices, meibomian gland secretion scores and meibomian gland dropout scores (r=0.708, P=0.000; r=0.759, P=0.000; r=0.270, P=0.003). BUT showed negative correlation with meibomian parameters (r=-0.692, P=0.000; r=-0.691, P=0.000; r=-0.192, P=0.036).

Keratograph 5M provides an effective noninvasive method in assessing the image of the meibomian gland structures and meibomian gland dropout.There are differences in the ocular surface and meibomian glands between the OMGD patients and normal persons.

Meibomian gland dysfunction; Meibomian gland dropout; Ocular surface disease index; Keratograph 5M