[Correlation between tyndallometry with the "laser flare cell meter" in vivo and biochemical protein determination in human aqueous humor].
BACKGROUND
The laser flare-cell meter allows noninvasive measurement of aqueous flare in humans. In vitro studies have shown good correlations between flare values and albumin concentrations. In this study, we compared aqueous flare values and aqueous protein concentrations in living human eyes.


METHODS
We measured aqueous flare and the total aqueous protein concentration in 52 eyes of 52 patients (age 58.4 +/- 18.8 years) that underwent cataract extraction (22 eyes) or trabeculectomy (30 eyes). Before surgery, aqueous flare was determined with the laser flare-cell meter (Kowa FC-1000). During surgery, 50 microliters of primary aqueous humor was aspired, and total aqueous protein concentration was performed using a modified Pierce-BCA assay. Linear regression analysis was calculated.


RESULTS
There was a high correlation between aqueous flare values and total aqueous protein concentration (y = 0.52x + 0.15, r = 0.98, p < 0.00001). This correlation was observed both in eyes with and without cataract.


CONCLUSIONS
Our results indicate that aqueous flare values as determined with the laser flare-cell meter reflect the true aqueous protein concentration quite accurately. Lens opacities appear not to significantly alter the results of aqueous flare measurements. As expected by theoretical assumptions, flare measurements overestimate aqueous protein concentrations in eyes with severely impaired blood-aqueous barriers because, according to Rayleigh's law, larger protein molecules cause more light scattering. However, transformation and expression of flare values as "albumin concentration equivalents" according to in vitro-calibration may still be useful, especially if the results of different instruments are to be compared.(ABSTRACT TRUNCATED AT 250 WORDS)
Küchle
M
M
Augenklinik mit Poliklinik, Universität Erlangen-Nürnberg.
Hannappel
E
E
Nguyen
N X
NX
Ho
S T
ST
Beck
W
W
Naumann
G O
GO
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001082:Aqueous Humor / Q000737:chemistry / Q000166:cytology*; D002387:Cataract Extraction; D002452:Cell Count; D005136:Eye Proteins / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D014130:Trabeculectomy
D005136:Eye Proteins
Korrelation zwischen Tyndallometrie mit dem "Laser Flare-Cell Meter" in vivo und biochemischer Proteinbestimmung im menschlichen Kammerwasser.