At Press Time

Research Digest

New & Noteworthy Journal Articks

Compiled by Andrew E. Mathis, PhD, Medical Editor

► Wills corneal ulcer study. To examine the trends in the development of contact lens-related ulcers, ophthalmologists at the Wills Eye Institute reviewed the medical records of all patients diagnosed with presumed bacterial corneal ulcers over a four-year period. The results of this retrospective review appear in the October 2012 issue of Cornea.

Of a total of 507 corneal ulcers identified in the retrospective record review; 223 were contact lens-related, with this proportion increasing significantly over time. The most common infectious agent was Pseudomonas aeruginosa (63% of positive cultures). Soft daily wear lenses were the most common type of lenses associated with ulcers (33.5% of cases).

Having previously found increases in contact lens-related ulcers from 1996 to 1996 and from 1999 to 2002, the authors concluded that daily disposable lenses have reduced, but not eliminated, infection rates.

► European glaucoma study. Doctors in the United Kingdom and at Johns Hopkins have collaborated on a systematic review and population model to determine the rate of primary angle closure glaucoma (PACG) in European-derived populations. They have reported their findings in the September 2012 issue of the British Journal of Ophthalmology.

First, the authors performed a literature review to identify all studies on PACG conducted in European-derived populations. Then, they compared the expected number of PACG cases to data on actual cases the United Nations provided.

The authors found that the prevalence of PACG in patients 40 years old or older was 0.4%, with the rates rising along with age. Women accounted for three-quarters of cases.

The authors concluded that PACG is two to four times more common than previously thought, and they recommended that all primary glaucoma cases be considered PACG until gonioscopy shows the anterior-chamber angle is open.

► Anti-VEGF failure study. Lucentis (ranibizumab) has revolutionized the treatment of wet AMD, but some patients still do not respond to treatment with the anti-VEGF agent. The August 2012 issue of Retina features an article by retinal physicians in France, who undertook a retrospective study to determine the causes of treatment failure.

Of 290 eyes the authors studied, 7.24% suffered mean vision loss of 27 ETDRS letters. The most common causes of vision loss were progression of atrophy, scarring or both. Patients who lost vision tended to be older and have worse visual acuity at baseline.

The authors concluded that the causes of vision loss during treatment with Lucentis tended to be related to the natural history of the disease itself and not the actual treatment. Notably, the MARINA and ANCHOR studies, the phase 3 studies upon which the FDA approved Lucentis, did not find these causes for treatment failure, although the French authors' findings did resemble those from the PrONTO variable-dosing study.

► Low vision intervention. The Low Vision Intervention Trial (LOVIT) was conducted from November 2004 to November 2006 by the Veterans Administration to evaluate the effectiveness of low-vision rehabilitation in 126 veterans with visual acuity between 20/100 and 20/500. In the September 2012 issue of Archives of Ophthalmology, outcomes of 100 patients from that trial were compared to determine the efficacy of the treatments they received.

The patients who had been randomized to receive the treatment under study in LOVIT improved maximally in visual ability, while visual ability worsened in the control group, who waited four months before receiving standard treatment. However, after four months, the differences between the groups began to disappear. By the end of the study period (one year), the study group had improved more than the control group in terms of overall visual ability.

The authors concluded that the LOVIT intervention was highly successful and well maintained. That this intervention was better than the control invention was, in their opinion, a result of home visits and coverage for transportation expenses, among other factors.

► EyeCam results in angle closure. In the September 2012 issue of the Journal of Glaucoma, Clarity Medical Systems' EyeCam is put to the test against goniophotography and gonioscopy in the detection of angle closure. Eighty-five participants who were predominantly Chinese were submitted to all three examinations at a center in Singapore. The differences in angle closure detection among the three modalities were very small (45% with gonioscopy vs. 47% with EyeCam vs. 47% with goniophotography), although the similarity in findings was not statistically significant. The comparison between EyeCam and goniophotography was less favorable due to lack of agreement in the nasal and temporal quadrants.

The authors concluded that EyeCam is as good as goniophotography in detecting angle closure in these patients. While the authors concede that EyeCam is more laborintensive to apply, they believe it could be a useful adjunct to gonioscopy.

► Glaucoma and diet. Ophthalmologists collaborating across several centers in the United States and publishing in the October 2012 issue of the American Journal of Ophthalmology have found that African-American women who eat three or more servings per day of fruits and fruit juices were 79% less likely to develop glaucoma than demographically similar women who consumed less than one serving per day. The study authors observed similar trends with the consumption of oranges, peaches, collard greens and kale. OM