Study shows MicroPulse laser controls IOP after keratoplasty

VANCOUVER, British Columbia — Use of MicroPulse transscleral cyclophotocoagulation in patients after keratoplasty resulted in IOP control and minimal complications, according to a presentation here at the Association for Research in Vision and Ophthalmology meeting.

Jessica Minjy Kang, MD, and colleagues from the University of California, San Francisco, Department of Ophthalmology conducted a retrospective observational study of glaucoma patients with a history of penetrating keratoplasty (16 eyes) or Descemet’s stripping automated endothelial keratoplasty (14 eyes) who failed medical therapy and then were treated with MicroPulse transscleral cyclophotocoagulation (Iridex).

Patients were an average of 66 years old with an average baseline IOP of 27.7 mm Hg. They were followed for an average of 10.5 months, Kang said in her presentation. IOP, number of glaucoma medications, best corrected visual acuity and central corneal thickness were measured at baseline and 1, 3, 6 and 12 months postoperatively.

“IOP was significantly decreased from preop levels at all follow-up points,” Kang said. “Mean IOP reduction was 43.5% at postop month 12. The number of glaucoma medications was significantly reduced at postop month 3, and visual acuity was not significantly different at follow-up.”

Success criteria consisted of IOP between 5 mm Hg and 21 mm Hg or reduced at least 20% from baseline, no use of oral carbonic anhydrase inhibitors, no loss of light perception vision and no reoperation for glaucoma within the 12-month follow-up period, Kang said.

“Eighty percent of eyes met the definition of success at the 12-month follow-up,” she said.

One eye underwent repeat PK due to graft rejection.

Kang noted that the type of corneal transplant did not affect the IOP-lowering effect of the MicroPulse procedure, and there was no difference in complications in the two groups.

Anterior chamber inflammation was the most common complication, seen in 40% of eyes, but it resolved by postop month 3, Kang said.

“Compared to non-keratoplasty patients, we saw similar IOP effect with MicroPulse in post-keratoplasty patients,” she said. “Also compared to prior studies of transscleral cyclophotocoagulation in post-keratoplasty patients, MicroPulse demonstrated similar IOP lowering but with fewer complications.

“MicroPulse may help avoid incisional surgery while lowering IOP,” Kang said.

She noted that the sample size and retrospective nature of the study were limitations. – by Nancy Hemphill, ELS, FAAO

Reference:

Kang JM, et al. Clinical outcomes of MicroPulse transscleral cyclophotocoagulation in post-keratoplasty patients. Presented at: Association for Research in Vision and Ophthalmology; April 28-May 2, 2019; Vancouver.

Disclosures: The authors report no relevant financial disclosures.