Light scatter found to decrease post-DSEK, still higher than normal

FORT LAUDERDALE, Fla. — Backscattered light from the cornea decreases after Descemet's stripping with endothelial keratoplasty yet still remains higher than normal in the posterior two-thirds of the cornea, according to an ophthalmologist speaking here at the Association for Research in Vision and Ophthalmology meeting.

Keith H. Baratz, MD, and colleagues from the Mayo Clinic College of Medicine, Rochester, Minn., conducted a prospective, non-randomized study in 18 eyes of 16 patients, all with corneal edema from Fuchs' dystrophy.

Patients were evaluated preoperatively and at 1, 3, and 6 months postoperatively and were compared with a control group of 41 eyes in 41 patients.

Best corrected visual acuity was also measured. Researchers used ETDRS testing protocol, with mean BCVA reported at 0.46 ± 0.24 logMAR before surgery, 0.31 ± 0.22 logMAR at 3 months and 0.27 ± 0.14 logMAR at 6 months, according to Dr. Baratz.

Contrast sensitivity was tested using the Functional Acuity Contrast Test (Vision Sciences Research Corp.).

Before surgery, backscattered light was 69%, 55% and 115% higher than normal in the anterior, middle and posterior regions of the cornea, respectively. At 6 months after surgery, backscattered light decreased yet still remained 22% higher than normal in the middle region and 30% higher than normal in the posterior region.

Contrast sensitivity was significantly lower than normal after Descemet's stripping with endothelial keratoplasty (DSEK).

"Compared with [penetrating keratoplasty], the postoperative acuity is similar between the two groups, but contrast sensitivity is better after DSEK. Midstromal scatter is less after PK," Dr. Baratz said.