Open AccessReproducibility of laser Doppler imager flux measurements within ischemic or venous ulcers and adjacent skin
Author(s) -
Gschwandtner Michael E.,
Ambrózy Ewald,
Böhler Kornelia,
Fasching Sonja,
Gaggl Uwe,
Schneider Barbara,
Ehringer Herbert
Publication year - 1998
Publication title -
skin research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.521
H-Index - 69
eISSN - 1600-0846
pISSN - 0909-752X
DOI - 10.1111/j.1600-0846.1998.tb00114.x
Subject(s) - reproducibility , laser doppler velocimetry , medicine , coefficient of variation , nuclear medicine , biomedical engineering , skin thickness , laser , chemistry , blood flow , optics , chromatography , physics
Background/aims: The laser Doppler imager (LDI) is a device that maps the local distribution of the laser Doppler flux of tissues. To facilitate the interpretation of LDI measurements, we investigated their reproducibility. Methods: We measured 10 arterial ulcers, 10 venous ulcers and their adjacent skin by the use of a LDI. The means were calculated of individual coefficients of variation ± standard error of mean (mean CV ±SEM) of measurements on the same day, on 5 different days and at specific time points (0, 30, 60, 90 and 120 min) during the application of PGE, on 2 different days. Results: The mean CV ±SEM of measurements on the same day were 9.3±0.9% (ulcer), 9.8±0.9% (skin), and on 5 different days they were 21.9±1.9% (ulcer) and 28.6±2.4% (skin). Ulcer measurements on 5 different days were significantly more reproducible than skin measurements, if differences were calculated for all 20 patients or for the 10 patients with venous ulcers separately ( P <0.05). During the application of PGE, for 120 min, mean CV ±SEM ranged from 19.2±4.0% to 26.9±5.0% (ulcer) and from 20.5±4.1% to 29.5+3.9% (skin). CV of skin measurements of all 20 patients at 0 min were significantly lower than those after 120 min of PGE 1 ‐application ( P <0.05). Conclusion: Our results show an excellent reproducibility of LDI measurements on a single day. The reproducibility of measurements on 5 different days or during the application of PGE 1 over a period of 120 min was poorer. Because of the poorer reproducibility, more patients are needed to study long‐term or drug effects.