Sources of variability in the quantification of tissue optical properties by multidiameter single-fiber reflectance and fluorescence spectroscopy.
Recently, a multidiameter single-fiber reflectance and fluorescence spectroscopy device has been developed that enabled us to extract the autofluorescence of tissue that is corrected for the optical properties. Such a system has been incorporated in the population-based Rotterdam Study to investigate the autofluorescence of the skin. Since the device will be used by different operators over many years, it is essential that the results are comparable between users. It is, however, unclear how different methods of handling the probe might influence the outcome. Variability of blood oxygen saturation, blood volume fraction and vessel diameter, average gamma, reduced scattering coefficient at 800 nm, and integrated intrinsic fluorescence measured in three volunteers were assessed within and between eight untrained users. A variability of less than one standard deviation from the group mean was defined as an acceptable limit. Three mature volunteers were also included to assess the intrauser variability of mature skin. The variation in the measured parameters suggests that variation is dominated by tissue heterogeneity. Most users measured within one standard deviation of the group mean. Notably, corrected intrinsic fluorescence showed low intra- and interuser variability. These results strongly suggest that variability is mostly caused by tissue heterogeneity and is not user induced.
Erasmus Medical Center, Center for Optical Diagnostics and Therapy, Department of Dermatology, P.O. Box 2040, Rotterdam 3000 CA, The Netherlands.
Sander
S
Brooks
Erasmus Medical Center, Center for Optical Diagnostics and Therapy, Department of Dermatology, P.O. Box 2040, Rotterdam 3000 CA, The Netherlands.
Christopher L
CL
Hoy
Erasmus Medical Center, Center for Optical Diagnostics and Therapy, Department of Dermatology, P.O. Box 2040, Rotterdam 3000 CA, The Netherlands.
Arjen
A
Amelink
Erasmus Medical Center, Center for Optical Diagnostics and Therapy, Department of Otolaryngology, Head and Neck Surgery, P.O. Box 2040, Rotterdam 3000 CA, The Netherlands.
Dominic J
DJ
Robinson
Erasmus Medical Center, Center for Optical Diagnostics and Therapy, Department of Dermatology, P.O. Box 2040, Rotterdam 3000 CA, The Netherlands.
Tamar E
TE
Nijsten
D000328:Adult; D000368:Aged; D016477:Artifacts; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000379:methods*; D006801:Humans; D008027:Light; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012867:Skin / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*