Evaluating the Short-Term Effects on Semi-automated Aqueous Flare Assessment After Fundus Fluorescein Angiography Imaging

Abstract

Purpose : To evaluate the change of aqueous flare values at 30 mins and 4 hours after fundus fluorescein angiography (FFA) imaging session.

Methods : In this prospective study, patients were enrolled from a uveitis clinic at Gazi University (Ankara, Turkey). All patients initially underwent a dilated (cyclopentolate 1% and phenylephrine 2.5%) ophthalmological examination where the physician assessed the grade of aqueous flare. Patients, who were scheduled to have fluorescein angiography imaging, were asked to participate in the study; consent was obtained. Thirty minutes before the FFA imaging session, a masked operator performed aqueous flare measurement on the patients using the laser flare meter (Kowa FM-700). The same operator also performed aqueous flare measurement 30 minutes and 4 hours after the FFA imaging session. The mean flare values were obtained at the three time points. The outliers for measured flare values were removed. Student paired t-test analysis was performed using Stata, version 15.1 (Stata Corp LLC, College Station, Texas USA); p-value <0.05 was deemed significant.

Results : Fourteen (14) patients (28 eyes) were included in the study. Four eyes were excluded due to extreme values; 24 eyes were analyzed. At baseline, the mean age of patients was 32.21 years, and 6 patients (43%) were female. Among 14 patients, 5 were diagnosed with pars planitis, 3 anterior uveitis, 4 posterior uveitis and 2 others. The mean intraocular pressure (IOP) at baseline was 13.86 ± 2.01 (mmHg). The mean laser flare values (±SE) were 10.05 ± 1.52, 9.21 ± 1.43, and 9.27 ± 1.47 (photon counts/millisecond) for 30 mins before, 30 mins after, and 4 hours after the FFA imaging section, respectively. The difference between laser flare measurement 30-min before and 30-min after was statistically significant (p-value=0.03). However, the difference between 30-min before and 4-hour after was not statistically significant (p-value=0.10).

Conclusions : Administration of fluorescein does not increase flare values. During FFA, laser flare values decreased in the early period after fluorescein administration. However, the effect on flare seems to normalize over time.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.