In a retrospective chart review, researchers from the department of ophthalmology at the University of Edinburgh, U.K., examined the outcomes of laser peripheral iridotomy for primary angle closure and determined predictors of future lens extraction. 

The investigators analyzed 218 eyes from 128 consecutive patients who underwent LPI between 2010 and 2012 at a university hospital. Baseline factors included age, peak intraocular pressure before LPI, diagnosis (primary angle closure suspect, primary angle closure, primary angle closure glaucoma) and acute or nonacute presentation. 

Ninety-one of 218 eyes (41.7 percent) initially treated with LPI had LE during follow-up. For eyes with nonacute presentation, 12 percent, 25 percent and 32 percent had LE at one, two and three years, respectively. For eyes with acute presentation, 27 percent, 42 percent and 50 percent had LE at one, two and three years, respectively. In univariable analysis, older age, higher IOP, worse visual field and primary angle closure glaucoma diagnosis were associated with LE, with older age and higher IOP remaining significant in multivariable analysis. There was a 1.09-fold increase in odds of LE for each year older at baseline. Each 1 mmHg higher IOP was associated with 1.08-fold increased odds of LE.

Based on these results, a large portion of patients with angle closure treated with LPI went on to require LE. Patients with features associated with higher odds of needing LE might be considered for LE as a primary procedure, the researchers say. 

J Glaucoma 2018;27:275-280

Bo J, Vhangulani T, Cheng ML, Tatham AJ

Riboflavin Dosing Intervals in Corneal Cross-linking

Researchers from the Cornea Research Foundation of America in Indianapolis investigated whether riboflavin dosing frequency affects corneal cross-linking efficacy and/or safety, given that isotonic riboflavin solution is viscous and each instillation coats the corneal surface with a film that absorbs some of the incident ultraviolet-A light. 

In this prospective, randomized, single-center equivalence trial, researchers studied patients (n=510) with progressive keratoconus or ectasia after refractive surgery. One eye per patient was prospectively randomized to two-minute or five-minute riboflavin dosing intervals with standard corneal cross-linking. Block randomization resulted in comparable representation of keratoconus and ectasia after refractive surgery in the two treatment arms. Fellow eyes (n=207) were treated with five-minute dosing and considered in the safety analysis.

The mean reduction in maximum keratometry from baseline was statistically equivalent in the two- and five-minute riboflavin dosing intervals at six months (0.97 and 0.76 D, respectively; 90 percent confidence interval for treatment difference, -0.23 to 0.66; per-protocol population). With both dosing intervals, the mean improvement in corrected distance visual acuity was 3.5 letters at six months. Of the 635 study and fellow eyes examined at six months, 134 (21 percent) gained and 32 (5 percent) lost two or more lines of CDVA. Three eyes (0.4 percent) developed sterile infiltrates, one (0.1 percent) had delayed epithelial healing with dendrites and three (0.4 percent) had recurrent epithelial defects. Three eyes (0.4 percent) were retreated.

The researchers concluded that the two riboflavin dosing regimens produced equivalent reduction in the maximum keratometry value, with a favorable safety profile. 

Ophthalmol 2018;125:505-511

Price MO, Fairchild K, Feng MT, Price FW Jr. 

Long-term Remission of Neovascular AMD

Researchers from the Shiley Eye Institute, University of California, conducted a study to determine the presenting characteristics of patients with neovascular age-related macular degeneration with long-term remission, which was defined as the absence of intraretinal/subretinal fluid or hemorrhage, and the absence of leakage on fluorescein angiography, for longer than six months while on as-needed antivascular endothelial growth factor treatment.

The presenting characteristics of patients with LTR were compared with a control group including 32 eyes of 28 age-, gender- and ethnicity-matched patients who did not achieve LTR.

Seventy-four percent of patients in the LTR group had Type-1 choroidal neovascular membrane, and 18.5 percent had retinal angiomatous proliferation. In the control group, 28 eyes had Type-1 choroidal neovascular membrane (87.5 percent), and none of the patients had retinal angiomatous proliferation. Overall, there was a significant difference in lesion types between the two groups (p=0.036). Eyes with LTR at presentation had significantly thinner subfoveal choroidal thickness (147 vs. 178 µm, p=0.04). There was more intraretinal fluid and less subretinal fluid at presentation in the remission group (59.3 percent intraretinal fluid and 11.1 percent subretinal fluid) compared with the control group (28.1 percent intraretinal fluid and 34.4 percent subretinal fluid, p=0.03).

According to the results of the study, the presence of retinal angiomatous proliferation, thinner choroidal thickness, more intraretinal fluid and less subretinal fluid at presentation were associated with LTR in patients receiving as-needed treatment for AMD.

Retina 2018;38:516-522

Muftuoglu IL, Alam M, You QS, et al. 

Association Between BMI and Open-angle Glaucoma

A study was conducted to investigate the association between body mass index and open-angle glaucoma in a sample of the South Korean population.

The researchers looked at a group that consisted of a cross-sectional, population-based sample of 10,978 participants, 40 years of age and older, enrolled in the 2008 to 2011 Korean National Health and Nutrition Examination Survey. All participants had measured intraocular pressure <22 mmHg and open anterior chamber angles. OAG was defined using disc and visual field criteria established by the International Society for Geographical and Epidemiological Ophthalmology. Multivariable analyses were performed to determine the association between BMI and OAG. These analyses were also performed in a sex-stratified and age-stratified manner.

After adjusting for potential confounding variables, lower BMI (<19 kg/m) was associated with greater risk of OAG compared with normal BMI (19 to 24.9 kg/m) [odds ratio, 2.28; 95 percent confidence interval (CI), 1.22-4.26]. In sex-stratified analyses, low BMI remained related to glaucoma in women (OR, 3.45; 95 percent CI, 1.42-8.38) but not in men (OR, 1.72; 95 percent CI, 0.71-4.20). In age-stratified analyses, lower BMI was related to glaucoma among subjects 40 to 49 years old (OR, 5.16; 95 percent CI, 1.86-14.36) but differences in glaucoma prevalence weren’t statistically significant between those with low versus normal BMI in other age strata.

Based on these results, lower BMI was associated with increased odds of OAG in this population. Multivariate analysis revealed the association to be statistically significant in women and those in the youngest age stratum.

J Glaucoma 2018;27:239-245

Lin SC, Pasquale LR, Singh K, Lin SC

Trabeculectomy Alone vs. Trabs with Ex-Press Shunts

Scientists compared postoperative interventions and outcomes between conventional trabeculectomy and trabeculectomy with the Ex-Press mini glaucoma shunt device, as part of a retrospective, comparative, single-facility study. 

They analyzed the cases of 108 individuals with glaucoma who underwent trabeculectomy and were followed for longer than a year. Thirty-nine eyes underwent a conventional trabeculectomy (conventional group), and 69 eyes underwent a trabeculectomy with an Ex-Press. Scientists examined postoperative intraocular pressure, the surgical success rate, postoperative complications, and the number of days to laser suture lysis and needling.

The trabeculectomy significantly decreased IOP values from 27.8 ±7.9 to 11.1 ±3.9 mmHg in the conventional group (p<0.001) and from 27.7 ±9.2 to 11.5 ±3.7 mmHg in the Ex-Press group (p<0.001) after one year. The success rate wasn’t significantly different between groups. The timing of the first laser suture lysis was significantly sooner in the Ex-Press group, but the Ex-Press group showed significantly less choroidal detachment due to low IOP.

The authors concluded that, in individuals whose trabeculectomy treatment included an Ex-Press, earlier laser suture lysis was required to obtain outcomes comparable to those of conventional trabeculectomy.

Clin Ophthalmol 2018;12:643-50.

Tojo N, Otsuka M, Hayashi A, et al.