An intravitreal injection regimen for age-related macular degeneration may provide meibomian gland (MG) protection and help stave off dry eye, according to a report published in Ophthalmology. Patients with AMD who undergo repeated treatments of anti vascular endothelial growth factor (anti-VEGF) drugs with preoperative povidone-iodine application experience less MG loss, increased tear volume, and reduced signs of inflammation compared to fellow non-treated eyes in patients with neovascular AMD, according to researchers.
The 90 participants in this retrospective observational analysis were on average 77.5 (SD 8.4) years of age, undergoing unilateral anti-VEGF therapy for nAMD at the Department of Ophthalmology, Stavanger University Hospital, Norway (ClinicalTrials.gov, (NCT04458012). Those with eyelid disorders were excluded. Patients, on a treat-and-extend regimen, received a median of 19.5 injections, 8 in the year prior to the analysis, and 13 consistently used artificial tears bilaterally. .
Median time from prior injection until the ocular surface examination was 4 weeks (range 4 to 14 weeks). Using uninjected fellow eyes as controls, median tear meniscus height (TMH) measured 0.36 mm (IQR 0.28 to 0.52 mm) in eyes receiving injections vs 0.32 mm (IQR 0.24 to 0.49 mm) in fellow eyes (P =.02). Similarly, treated eyes had an average bulbar redness score of 1.32 (SD 0.46), compared with control eyes at 1.44 (SD 0.45), also significant (P =.017)
Important differences also emerged in meibography, according to the investigators. Interpretable images of lower lids were achieved in 88% of patients, and for these, median MG loss was 17.4% (IQR 9.4%-29.9%) in eyes undergoing injections, and 24.5% (IQR 14.2%-35.2%) for fellow eyes (P <.001). Fewer gradable images resulted for upper lids — 37%, although findings resembled those of the lower eyelids. Mean upper lid MG loss reached 19.1% (SD 11.3%) in treated eyes vs 25.5% (SD 14.6%) in controls (P =.001).
Investigators found no significant differences in noninvasive or fluorescein tear film break-up time (TBUT), corneal staining, tear film osmolarity, Schirmer test, MG expressibility or meibum quality.
“The most conspicuous hypotheses are either the effect of repeated application of PVP-I, which has antibacterial properties that can be protective against ocular surface damage associated with eyelid margin diseases, or the role of VEGF, which is a known mediator of inflammatory responses,” according to the investigators.
Previous research showed increasing microbiome quantity and complexity with progressing MG dysfunction. In other work involving patients with MG dysfunction, bevacizumab injected into MG improved TBUT, redness, and other factors. Further, prior studies have found corneal epitheliopathy in eyes exposed to povidone-iodine (PVP-I), but the present data did not uncover any differences relating to corneal damage among treated and untreated eyes. The investigators speculate this may have been due to an extended duration between injection and ocular surface testing.
A limitation of this analysis is semi-automatic measurement of MG dropout with ImageJ software which may have yielded varying images and less repeatability of evaluator estimation. The study design does not prove causality. Strengths included a sample with a high number of ongoing injections, and evaluator masking to treatment eye. Also, since the clinic does not use topical antibiotics or artificial tears immediately after injections, no bias resulted from preservatives or lubrication-associated surface changes.
Malmin A, Thomseth VM, Forland PT, et al. Associations between serial intravitreal injections and dry eye. Ophthalmol. Published online on January 21, 2023. doi:10.1016/j.ophtha.2023.01.009