A small-aperture corneal inlay (Kamra, AcuFocus, Irvine, California, USA) for presbyopia yielded superb results in an analysis of long-term data.
Monocular uncorrected near visual acuity (UNVA) improved by an average 3.4 lines, intermediate visual acuity improved slightly and distance visual acuity was unchanged - all of which is very encouraging for patients with presbyopia, according to Dr John A. Vukich, surgical director, Davis Duehr Dean Center for Refractive Surgery, Madison, Wisconsin, USA.
Dr Vukich highlighted 3-year data from the prospective, non-randomized US clinical trial with the inlay that included 507 patients who were naturally occurring presbyopic emmetropes (age range, 45 to 60 years).
All patients had UNVA worse than 20/40 and better than 20/100. Best-corrected distance visual acuity was 20/20 or better bilaterally.
Implantation of the corneal inlay - a monocular procedure that is performed in the non-dominant eye - is performed during an intralamellar dissection that resembles a pocket into which the device is positioned over the pupil.
Eyes with the inlay had an average gain in monocular UNVA of 3.4 lines preoperatively to 36 months after implantation, Dr Vukich noted.
36-month follow-up period
"Importantly, this gain in vision was a sustained improvement that was maintained over the 36-month follow-up period," Dr Vukich said.
All study eyes completed the 36-month follow-up examination.
An important consideration in patients with presbyopia is the status of intermediate vision. In the study eyes, monocular uncorrected intermediate visual acuity (UIVA) improved, but as expected not to the same extent as near vision. The mean UIVA was 20/25.
"It is important that there was no loss of intermediate vision during the follow-up period," he said.
In addition, monocular uncorrected distance visual acuity was maintained over the course of the study in the eyes with the inlay.
"The average distance visual acuity remained better than 20/20," Dr Vukich said.
Excellent uncorrected distance binocular visual acuity also was maintained at an average of 20/16 over the duration of the study.
Long-term results showed that UNVA improved from a mean of J8 to J2 in the eyes with the inlay from preoperatively to 1 month postoperatively and was maintained to 5 years after surgery. The vision in the eye with the inlay and in both eyes was unaffected by the progression of presbyopia, Dr Vukich explained.
He noted that - while 5 years after surgery, normal progression of presbyopia would be expected as a result of lessening of the accommodative ability - the patients continue to do well despite natural presbyopic progression.
"This indicates that the vision is unaffected by the continuing presbyopic changes," Dr Vukich said. "This is certainly encouraging."