Purpose: The purposes of this study were to determine whether 2 laser flare photometry (LFP) devices produce similar results using various statistical techniques for determining a single, final LFP value for anterior chamber protein level; to determine whether a traditional technique adequately addresses outlier measurements; and to identify a simpler technique that produces LFP values similar to the traditional technique.
Design: Prospective cross-sectional study.
Participants: Patients at a tertiary referral center who have histories of uveitis in 1 or both eyes.
Methods: Seven LFP measurements were obtained on 200 eyes (100 patients) using Kowa FM-500 and FM-700 laser flare photometers (Kowa Company, Ltd). For each device, the final LFP values were determined using 4 statistical outlier removal techniques on all measurements and by means and medians for all 7 and for the first 5 measurements. The final LFP values by each technique were compared between the devices. Using the FM-700, host- and disease-related factors (age, sex, laterality, uveitis history, uveitis activity, and LFP values) were evaluated for their effects on outliers. Laser flare photometry values by each technique were compared with the LFP value by the traditional technique. Intraclass correlation coefficient (ICC) was used to compare values.
Main outcome measures: Laser flare photometry values by various techniques.
Results: The mean age of participants was 49.5 ± 19.1 years; 72% were female. Final LFP values did not vary meaningfully between the 2 devices for any technique (all ICCs: 0.81). With 5 measurements, no subgroup factors influenced the presence of outliers, and no final LFP values varied meaningfully from the final LFP value determined by the traditional technique (ICC: 0.97-1.00).
Conclusions: The automated mean provided by the FM-700 device based on 5 consecutive measurements may be a suitable final LFP value for use in patient care and clinical research.
Financial disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
Keywords: Anterior chamber flare; Intraocular inflammation; Laser flare photometry; Uveitis.
© 2024 by the American Academy of Ophthalmologyé.