Tyndallometry with the laser flare cell meter and biochemical protein determination in the aqueous humor of eyes with pseudoexfoliation syndrome

Slit-lamp examination and flare measurement in eyes with pseudoexfoliation (PSX) syndrome frequently reveal signs of impairment of the blood-aqueous barrier. We studied both aqueous flare and aqueous protein concentration in PSX eyes to verify and quantify these alterations. PATIENTS: Aqueous flare was measured using the Laser Flare-Cell Meter Kowa FC-1000 in 158 normal control eyes (age 56.0 +/- 12.0 years), in 60 PSX eyes (age 72.5 +/- 9.4 years), and in 84 eyes with primary chronic open-angle glaucoma (PCOAG) (age 56.3 +/- 12.4 years). Total aqueous protein concentration was determined biochemically in 12 "normal" control eyes with senile cataracts (age 57.6 +/- 20.4 years), in 27 PSX eyes (age 72.6 +/- 9.1 years), and in 25 PCOAG eyes (age 63.3 +/- 13.5 years). After the primary aqueous humor was aspirated during cataract extraction or trabeculectomy, a modified BCA-Peirce method was employed. RESULTS: In PSX eyes, both aqueous flare (12.3 +/- 8.2 photon counts/ms) and aqueous protein concentration (0.42 +/- 0.16 mg/ml total protein) were significantly increased in comparison with normal control eyes (4.3 +/- 1.1 photon counts/ms and 0.22 +/- 0.08 mg/ml) and with PCOAG eyes (4.7 +/- 1.6 photon counts/ms and 0.26 +/- 0.09 mg/ml) (P 0.05). There was a high correlation between aqueous flare measurements and aqueous protein concentration in eyes with PSX (y = 0.27x + 0.29, r = 0.65, P = 0.0006, n = 24). CONCLUSIONS: Our results indicate that impairment of the blood-aqueous barrier with an increase in aqueous protein concentration is a feature of PSX and may be quantified both by flare measurement and biochemical protein determination. These alterations should be considered in the pharmacological and surgical treatment of PSX eyes.