Abstract
Purpose:
Ocular graft-versus-host disease (GvHD) following allogenic stem cell transplantation (aSCT) includes inflammation of the entire lacrimal functional unit, leading to severe damage of the ocular surface. In this context, meibomian gland loss in ocular GvHD was described as one pathophysiologic mechanism, however no information is available on the time course of meibomian gland loss in the process of ocular GvHD. This retrospective study was set up to analyze when meibomian gland loss occurs related to the time point of aSCT.
Methods:
Infrared images of upper lid meibomian glands from 72 GvHD-patients, 15 patients prior to aSCT and 20 healthy controls were recorded using the Oculus Keratograph 5 (Oculus, Wetzlar, Germany). The images were evaluated using Olympus Soft Imaging Solution's Cell^F 3.4 with using shading correction and contrast optimization. The images were then binarized and further filters (erosion and dilatation) were applied. Upper meibomian gland area (uMGA) was calculated and set in relation to the total tarsal area of the lid. Statistical analysis included Kruskall-Wallis-Test and Mann-Whitney U-test. p-values <0.016 were regarded as statistically significant.
Results:
Upper meibomian gland area (uMGA) was reliably calculated in all images recorded. Comparison of right and left eyes demonstrated no significant difference. Mean uMGA of GvHD patients was 24.6% (+/- 12.6), which was significantly lower (p=0.007) than healthy controls (33.9% +/- 8.9). Interestingly uMGA in patients prior to aSCT was statistically not different from GvHD patients (23.9% +/- 11.1, p=0.7) but statistically significant lower than in healthy controls (p=0.008).
Conclusions:
This study implicates that meibomian gland loss in GvHD patients is a multi-hit process that also occurs prior to aSCT, possibly due to the underlying diseases and/or related chemotherapy or irradiation. Further follow-up studies need to be conducted to investigate mechanisms of meibomian gland loss and to identify high-risk from low-risk patients and procedures. Overall infrared meibography should be included in the routine workup of patients undergoing aSCT and during follow-up.
Keywords: 550 imaging/image analysis: clinical •
486 cornea: tears/tear film/dry eye •
432 autoimmune disease