Microperimetry could provide extra info on macula function

Microperimetry may provide additional information on macula function that is not available using visual acuity data, according to a study in Retina.

A team led by Dr M. Parravano, Fondazione G.B. Bietti-IRCCS, Rome, Italy, evaluated 18 neovascular AMD patients in a retrospective 24-week follow-up study. All patients received three injections of ranibizumab 0.5 mg one month apart and were retreated according to predefined criteria.

Baseline measurements included visual acuity, fluorescein angiography, microperimetry and optical coherence tomography stratus. Measurements for visual acuity, microperimetry and OCT evaluations were also conducted 28 days after each injection.

Mean retinal sensitivity significantly improved from a baseline of 3.89 ± 3.0 dB to 6.61 ± 3.4 dB at 24 weeks. Mean visual acuity improved from 48.67 ± 8.58 to 60.72 ± 16.09, with 44.4% of patients gaining 15 letters or more and 38.9% gaining a mean of 6.14 ± 3.7 letters. However, 16.7% of patients lost a mean of 7.3 ± 2.1 letters.

Fixation stability improved from baseline in 33.3% of patients and central macula thickness significantly decreased from 310.5 ± 85.7 µ to 217.3 ± 46.8 µ at 24 weeks.

Overall, visual acuity and retinal thickness changes appeared to peak at four weeks after the administration of intravitreal ranibizumab 0.5 mg. Retinal sensitivity measured by microperimetry presented a trend of progressive improvement until 24 weeks.

To read the abstract please click here.