This study by the Writing Committee for the Diabetic Retinopathy Clinical Research Network compared two laser photocoagulation techniques for treatment of diabetic macular edema (DME): the modified Early Treatment Diabetic Retinopathy Study (ETDRS) direct/grid photocoagulation technique and a potentially milder, but potentially more extensive, mild macular grid (MMG) laser technique in which microaneurysms are not treated directly and small mild burns are placed throughout the macula, whether or not edema is present.

The study included 263 subjects (mean age, 59 years) with previously untreated DME who were randomly assigned to receive laser photocoagulation either by the modified ETDRS (162 eyes) or MMG (161 eyes) technique. Investigators obtained visual acuity, fundus photographs and optical coherence tomography measurements at baseline and at 3.5, eight and 12 months. Treatment was repeated if DME persisted.

Among study eyes with a baseline central subfield thickness of 250 microns or greater, central subfield thickening decreased by an average of 88 microns in the modified ETDRS group and by 49 microns in the MMG group at 12-month follow-up. Weighted inner zone thickening by optical coherence tomography decreased by 42 microns in the modified ETDRS group and by 28 microns in the MMG group; maximum retinal thickening (maximum thickening of the central and four inner subfields) decreased by 66 and 39 microns, respectively and retinal volume decreased by 0.8 and 0.4 mm3, respectively. At 12 months, the mean change in visual acuity was zero letters in the modified ETDRS group and two letters worse in the MMG group.

At 12 months, the mean change in visual acuity was zero letters in the modified ETDRS group and two letters worse in the MMG group. At 12 months after treatment, the MMG technique was less effective at reducing optical coherence tomography-measured retinal thickening than the more extensively evaluated current modified ETDRS laser photocoagulation approach. However, the authors of the study believe that the visual acuity outcome with both approaches is not substantially different. Given these findings, they determined that a larger long-term trial of the MMG technique is not justified and that modified ETDRS focal photocoagulation should continue to be a standard approach for treating DME.

This randomized prospective long-term trial compared at two, three, and four years after surgery the effect on best-corrected visual acuity (BCVA) of anterior chamber (AC) intraocular lenses (IOLs) and posterior chamber (PC) IOLs implanted after vitreous presentation (VP) during extracapsular cataract extraction in patients with sufficient capsular support for a nonsutured PC IOL.

Patients at 19 Department of Veterans Affairs Medical Centers having VP during cataract surgery with sufficient capsular support were randomized to receive either a PC IOL (230 patients) or an AC IOL (208 patients). Patients having insufficient capsular support (ICS; 143 patients) and a 5 percent random sample of nonvitreous presentation patients (NVP; 521 patients) were prospectively followed in the same fashion.

Results showed no significant difference on the major outcome measure of BCVA of 20/40 or better between the PC IOL and AC IOL groups at two (88.7 percent vs. 82.2 percent), three (82.5 percent vs. 91.8 percent), and four (88.6 percent vs. 92.6 percent) years of follow-up. The ICS patients had significantly worse BCVA or a trend to be worse BCVA of 20/40 or better than the other three groups at two and four years.

The authors of the study concluded that, although PC IOLs are better than AC IOLs on the major outcome measure at one year, this trend did not continue over the longer term. The poor results for ICS patients reported previously at one year continue at two and four years.