Comparison of fluorescein break-up time measurement reproducibility using standard fluorescein strips versus the Dry Eye Test (DET) method

Purpose. To compare the repeatability of fluorescein break-up time (FBUT) m easurements determined with either a standard fluorescein strip or the Dry Eye Test (DET) modified fluorescein strip methods. Methods. This was a pros pective, randomized contralateral study of 100 patients, in which FBUT meas urements were determined with a standard FUL-GLO fluorescein strip (Akorn, Inc., Buffalo Grove, IL, U.S.A.) in one eye and a DET strip (Akorn, Inc., B uffalo Grove, IL, U.S.A.) for the contralateral. eye. Three consecutive mea surements were made immediately after fluorescein instillation. The second eye was evaluated I minute after completion of the first eye. Data from pat ients with FBUT values less than 20 seconds were included in the data analy sis, because measurements greater than 20 seconds are not diagnostically si gnificant. Results. Seventy-five patients met enrollment and FBUT measureme nt criteria. For three consecutive FBUT measurements, the DET values were w ithin 3 seconds for 72 of the 75 patients (96%). Eighty percent of patients reported no sensation with the DET strip, 20% reported mild sensation, and no patient reported moderate sensation. With FUL-GLO strips, measurements were within 3 seconds for 53 of the 75 patients (71%) (p <0.005). The stand ard fluorescein strip method elicited reports of no sensation from 31% of p atients, mild sensation from 60%, and moderate sensation from 9% (p <0.001) . Conclusions. The DET strip provides a significant reduction in sensation upon application, improved single measurement reliability, and enhanced mea surement precision, compared with a conventional fluorescein strip.