[Tyndallometry with the laser flare cell meter in intraocular inflammation].

The laser flare-cell meter (LFCM) allows noninvasive, quantitative measurement of aqueous flare in human eyes. In this study we analysed changes in aqueous flare in eyes with various forms of intraocular inflammations. PATIENTS. We examined 100 eyes of 100 patients aged (mean +/- SD) 40.2 +/- 19.8 years with acute and chronic intraocular inflammations. The inflammatory diseases were classified according to morphological criteria. In addition, 163 normal eyes of 163 subjects (mean age 44.8 +/- 17.9 years) were evaluated. The eyes were examined by three examiners using the LFCM (Kowa, FC-1000) after pupillary dilatation with mydriatics. The instrument was calibrated with standardized concentrations of human albumin concentrations, and flare values were transformed into human albumin concentration equivalents. For statistical analysis, the non-parametric Wilcoxon-Mann-Whitney test was used. RESULTS. Flare values (mean +/- SD) in the eyes with intraocular inflammations were 4.38 +/- 11.82 mg/ml human albumin equivalents and were significantly higher than in the group of normal eyes (0.11 +/- 0.06 mg/ml, P < 0.0001). In addition, flare values differed in the various inflammation groups, with human albumin concentration equivalents decreasing in the following order: acute iridocyclitis (n = 27, 10.81 +/- 21.12), chronic iridocyclitis (n = 19, 5.19 +/- 6.12), necrotizing retinitis (n = 6, 1.92 +/- 1.11), acute retinochoroiditis (n = 9, 1.46 +/- 2.35), retinal vasculitis (n = 24, 1.03 +/- 0.90), chorioretinitis (n = 5, 0.98 +/- 0.71), Fuchs' uveitis (n = 10, 0.52 +/- 0.25). CONCLUSION. Measurement of aqueous flare with the LFCM is a noninvasive examination that yields objective, quantitative and reproducible results and therefore has advantages over slit-lamp assessment. It gives valuable information about the integrity or impairment of the blood-aqueous barrier. Its possible clinical applications include follow-up examinations and "monitoring" of therapeutic regimens in uveitis.