Quantitative determination of aqueous flare and cells in the eyes of patients with inflammation of anterior uvea

Objective To quantify aqueous flare and cells in the eyes of patients with inflammation of anterior uvea by FC-2000 laser flare cell meter (LFCM) , and to compare these results with those obtained with slit lamp microscopy. Methods Aqueous flare and cells of 194 eyes of 110 patients with inflammation of anterior uvea and 52 eyes of 52 healthy subjects were graded into 0, 1 + , 2 + , 3 + and 4 + scale based on a previously described system using slit lamp microscopy. LFCM was also used for evaluation of aqueous flare and cells. Results All eyes in normal individuals were graded as "0" scale of both flare and cells by silt lamp microscopy. Flare of grade 0,1+ and 2 + were noted in 74, 98 and 18 eyes, and cell of grade 0, 1 + , 2 + , 3 + and 4 + were noted in 124, 26, 19, 14 and 11 eyes in uveitis patients, respectively. LFCM examination revealed that the mean flare values in uveitis eyes with flare of grade 0,1+ and 2 + were 7. 9, 29. 5 and 189. 0 photon count/ms, respectively. In patients with flare of grade 3 + and 4 + , LFCM readings were unreliable because of increased background noise. There was significant correlation between slit lamp examination and the laser flare measurement for flare of grade 0,1+ and 2 + (r =0. 75 , P 0. 001). The mean flare values were significantly higher in patients with flare of grade 0,1+ and 2 + than that in normal controls (5. 3 pc/ms) ( t = 5. 872, P 0. 05). The mean cell numbers in the eyes with cell of grade 0, 1 + , 2 + , 3 + and 4 + were 1. 5, 12. 1 , 33. 9, 84. 9 and 193. 1 count/0. 5 mm3, respectively. The results of slit lamp examination showed significant correlation with laser cell counts measurement ( r = 0. 72, P 0.001). The mean cell numbers were significantly higher in uveitis patients than that in normal controls (0. 9 count/0.5 mm3) (t = 1. 351, P 0. 05). Conclusions Our results indicate that LFCM is able to evaluate precisely the mild and moderate breakdown of blood aqueous barrier and inflammation of the anterior uvea tract, therefore it provides an important parameter for the treatment of anterior uveitis. ( Chin J Ophthalmol, 2004,40:510-513)