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Skin-color-independent robust assessment of capillary refill time
  • Raquel P. de Souza Bachour,
  • Eduardo Lopes Dias,
  • George C. Cardoso
Raquel P. de Souza Bachour
Universidade de Sao Paulo Campus de Ribeirao Preto

Corresponding Author:[email protected]

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Eduardo Lopes Dias
Universidade de Sao Paulo Campus de Ribeirao Preto
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George C. Cardoso
Universidade de Sao Paulo Campus de Ribeirao Preto
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Capillary Refill Time (CRT) assesses peripheral perfusion in resource-limited settings. However, the repeatability and reproducibility of CRT measurements are limited for individuals with darker skin. This paper presents quantitative CRT measurements demonstrating good performance and repeatability across all Fitzpatrick skin phototypes. The study involved 22 volunteers and utilized controlled compression at 7 kPa, an RGB video camera, and cocircular polarized white LED light. CRT was determined by calculating the time constant of an exponential regression applied to the mean pixel intensity of the green (G) channel. An adaptive algorithm identifies the optimal regression region for noise reduction, and flags inappropriate readings. The results indicate that 80% of the CRT readings fell within a 20% range of the expected CRT value. The repetition standard deviation was 17%. These findings suggest the potential for developing reliable and reproducible quantitative CRT methods for robust measurements in patient triage, monitoring, and telehealth applications.
27 Feb 2023Submitted to Journal of Biophotonics
28 Feb 2023Assigned to Editor
28 Feb 2023Submission Checks Completed
28 Feb 2023Review(s) Completed, Editorial Evaluation Pending
28 Feb 2023Reviewer(s) Assigned
09 May 2023Editorial Decision: Revise Major
26 Jun 20231st Revision Received
26 Jun 2023Submission Checks Completed
26 Jun 2023Assigned to Editor
26 Jun 2023Reviewer(s) Assigned
26 Jun 2023Review(s) Completed, Editorial Evaluation Pending
19 Jul 2023Editorial Decision: Accept