Meibography guided intraductal meibomian gland probing using real-time infrared video feed

Abstract

Purpose: To evaluate use of infrared meibography video to visualise meibomian gland probing and correlate probe findings of intraductal space with meibography images.

Methods: Videos were reviewed and probe findings recorded of 996 probed gland orifices from 38 lower lids.

Results: 996/997 (99.9%) of gland orifices were successfully probed with 91.8% revealing probe location. There were no false passages. 14% (140/997) of all gland orifices showed whole gland atrophy (WGA) with 99.3% (139/140) probed to 1 mm. Cumulative probe findings for all WGA (not differ significantly from non-WGA) showed 106 (76%), 21 (15%) and 12 (9%) glands with fixed, non-fixed and no resistance (NR), respectively. Lids without WGA showed increased NR/total glands probed while lids with WGAs (≥5) showed increased NR/WGA compared with lids with only 1-4 WGAs (p=0.011, p=0.005, respectively, Mann-Whitney U test) suggesting bimodal NR profile. Visualisation of microtube placement was successfully obtained for therapeutic injections and retrieval of meibum specimens.

Conclusion: Video confirmed intraductal location and safety of devices. For 73% of non-WGA and 76% of WGAs as well as proximal ducts of glands with proximal atrophy, probing released fixed resistance restoring ductal integrity. A bimodal profile of NR suggests it is found with less diseased gland ducts as well as more advanced atrophic gland disease. Gland and ducts appeared flexible but not distendable while periglandular tissue appeared spongy. Visualisation of devices enables whole or localised gland therapy and meibum specimen retrieval, elegantly raising future research, therapeutic and regenerative opportunities.

Keywords: cornea; eye lids; inflammation; ocular surface.

Figure 1

(A–D) Location and presence of a 1, 2 and 4 mm probe (76 μm OD) as well as a 1 mm tube (110 μm OD), respectively, inside the duct of a meibomian gland. Note that acinar-ductule units are visible in some areas overlying the devices.

Figure 2

(A) Straightening of a mildly tortuous duct and gland during intraductal probing. The duct is noticeably tortuous in image before probing (black lines closely parallel the central ducts). (B) 4 mm probe has been advanced and is visualised within the duct tract. Note the duct and gland appear significantly straighter and the interglandular connective tissue area (arrows in A–C) seems reduced. (C) Immediately after probe withdrawal, persistent straightening of the proximal duct and gland. (D) At 2-month follow-up. The same gland with configuration of gland and interglandular tissue restored to near pre-probing appearance suggesting interglandular tissue is spongy, able to be compressed and re-expand allowing duct and gland flexibility.

Figure 3

Four images where (A) and (B) demonstrate presence and location of intraductal devices (maskin probe) within the central duct of an area lacking acinar-ductule units. (A) Probe within the central duct of whole gland atrophy lacking acinar-ductule units for whole gland. (B) Maskin probe within the central duct of proximal atrophy where the gland lacks acinar-ductule units proximal to areas of distal and mid-to-distal intact or faded acinar-ductule units (black lines parallel probe within central duct). (C) Microtube within the duct of a meibomian gland to retrieve meibum specimen. Note the forceps holding end of tube. (D) Microtube with retrieved meibum immediately after removal from gland.