In early July, researchers from the department of ophthalmology at Hacettepe University Faculty of Medicine, Ankara, Turkey, published findings from a study looking at the association of long-term prostaglandin analog use with meibomian gland dysfunction in medically treated glaucoma patients.  Researchers determined that long-term administration of PGA is associated with an obstructive type of MGD.

In their prospective, cross-sectional study (conducted in an academic setting), researchers looked at 70 eyes of 70 patients with a medical diagnosis of glaucoma that were on long-term (>12 months) topical hypotensive medications. Patients were classified based on whether they were on PGA or non-PGA classes of medications. Forty-five age-matched, healthy control subjects who were not on any topical medications were also included.

In total, 25 patients (35.7 percent) were on PGA monotherapy, 21 (30 percent) were treated with fixed or unfixed PGA combination regimens and 24 (34.3 percent) were on non-PGA medications. MGD prevalence was higher in patients treated with PGA monotherapy (92 percent) compared with those receiving non-PGA therapy (58.6 percent, p<0.02). The obstructive type of MGD was detected in the majority of patients treated with PGAs (95.7 percent). Grade two and three MGD was noted in 80.5 percent of patients using PGAs. Patients on PGAs had worse ocular surface disease index scores and ocular surface test results  than those of control subjects (p<0.001).

J Glaucoma 2016;25:770-774
Mehmet M, Enes, U, Sibel K, Jale K, Murat I.

Long-term Outcomes of DMEK
In this retrospective, consecutive case series, researchers sought to evaluate the long-term clinical outcomes (up to five years) after Descemet’s membrane endothelial keratoplasty. They found that DMEK not only provides fast visual rehabilitation but maintains its clinical outcome over a five-year follow-up period.

The researchers reviewed 310 DMEK operations for endothelial decompensation. Ninety-seven eyes of 84 patients met the inclusion criterion of a minimum three-year follow-up. Retrospective evaluation of clinical examinations occurred at one and three months and annually up to five years after DMEK.

Mean follow-up was 53 ±13 months. Corrected distance visual acuity improved from 0.62 ±0.42 logMAR before DMEK to 0.13 ±0.12 logMAR (p<0.001) postop. Fifty-seven percent of eyes without ocular comorbidities reached ≥20/25 at five years after DMEK. Endothelial cell density was stable after the initial post-surgical decrease, from 2,602 ±243 cells/mm2 before DMEK to 1,460 ±179 cells/mm2 at five years. Central corneal thickness decreased from 644 ±67 µm before DMEK to 557 ±49 µm at five years, with a minimum of 530 ±54 µm at three months. Cumulative probability of five-year graft survival was 95 percent.

Visual acuity and endothelial cell loss remained stable between three months and five years after DMEK.

Notwithstanding the limitations of the study’s retrospective nature and the relatively high proportion of patients lost to long-term follow-up, the investigators say these data support the implication that for patients meeting the characteristics of those in this study, the three- to five-year clinical results of DMEK are at least comparable to those previously reported for DSEK/DSAEK. The researchers add that these findings further strengthen DMEK as a first choice in the treatment of corneal endothelial dysfunction, and that further studies may demonstrate better long-term results.

J Ophthalmol 2016;69:218-226
Andreas S, Theofilos T, Friedrich K, Julia W.

Anterior Uveitis’ Effect on the Endothelium
In a cross-sectional, observational study, researchers investigated a possible effect of intraocular inflammation on corneal endothelium by measuring corneal endothelial cell density and morphologic variables in eyes with anterior uveitis. They also looked at factors that may influence these findings. They found that the observed relationships suggest that anterior segment inflammation adversely affects the corneal endothelium, but note that longitudinal studies are warranted to determine whether longstanding anterior uveitis increases the risk of endothelial dysfunction, especially in the setting of intraocular surgery.

Researchers looked at 52 patients (84 eyes) with histories of unilateral or bilateral anterior segment inflammation (anterior, intermediate or panuveitis).

They found that central ECD was lower among eyes that had undergone cataract or glaucoma surgery or both (n=28, p=0.0004). After exclusion of eyes with surgery, variables for eyes with uveitis (n=56) were compared with two historical populations of normal, age-matched controls and with contralateral eyes in individuals with unilateral uveitis. Central ECD was lower in eyes with uveitis than in control eyes for all age groups (p≤ 0.01 for four of six 10-year age intervals, compared with the primary control group).

Among patients with unilateral uveitis who had not undergone surgery in either eye (n=12), central ECD was lower in eyes with uveitis (2,324 cells/mm2) than in contralateral eyes (2,812.5 cells/mm2), and percentage of hexagonality was lower in eyes with uveitis (54 percent) than in contralateral eyes (58.8 percent). There was no significant difference in central corneal thickness between eyes with and without uveitis (p=0.27). No eyes had clinically apparent central corneal edema.

Relationships remained unchanged after exclusion of eyes with herpetic anterior uveitis, the researchers say. Host and disease-related characteristics were evaluated as risk factors for variations in outcome measures, and central ECD was correlated with the duration of active uveitis (r=−0.41; p<0.0001), maximum intraocular pressure during the course of disease (r=−0.40, p=0.0002), and maximum laser flare photometry value (r=−0.26, p=0.020).

Ophthalmology 2016;123:1637-1645
Abdullah A, Gary H, Fei Y, Mathew M, JoAnn G, Anthony A.