1. Blood Perfusion Imaging
PulseCam: High-resolution blood perfusion imaging using a camera and a pulse oximeter
Mayank Kumar1, James Suliburk2, Ashok Veeraraghavan1, and Ashutosh Sabharwal1
1Rice University 2Baylor College of Medicine
Under Review, Patent pending

2. Introduction
Blood perfusion is flow of blood to end organs and tissue; is vital in ensuring oxygen deliver to cells, and in maintaining metabolic homeostasis.
Measuring blood perfusion in tissue useful in critical care, wound care, plastic surgery, burn assessment
Laser speckle contrast imaging and laser Doppler imaging devices are commercially available for measuring blood perfusion maps.
But, these devices are bulky, expensive, and cumbersome to use, and are not routinely used in clinical settings like ICU care, during surgery etc.

3. Camera-only Blood perfusion imaging
Camera-only blood perfusion imaging suffers from low SNR problem.
Past works rely on spatial averaging to reduce noise, thereby compromising spatial resolution.
Image Credit: A. A. Kamshilin, V. Teplov, E. Nippolainen, S. Miridonov, and R. Giniatullin, “Variability of microcirculation detected by blood pulsation imaging.” PloS one, vol. 8, no. 2, p. e57117, Jan

4. Figure 5. Time traces of the BPA (black curves) and the mean intensity of the back-reflected light (blue curves) calculated for four subjects by data averaging within selected ROI of 8×8 pixels.
Kamshilin AA, Teplov V, Nippolainen E, Miridonov S, Giniatullin R (2013) Variability of Microcirculation Detected by Blood Pulsation Imaging. PLoS ONE 8(2): e doi: /journal.pone

5. PulseCam: a Multi-sensor modality
Camera: measures noisy blood volume waveform from each pixel
Sensor fusion algorithm
PulseOx: measures reliable blood volume waveform at a single spot
High resolution pulsatile perfusion map

6. PulseCam: Steps Involved

7. PulseCam: SNR Improvement
PulseCam provides an SNR improvement of around 0.5 – 3 dB

8. PulseCam Validation: PORH

9. PulseCam: Results Summary
On an average, we see an SNR improvement of dB per pixel block in the blood perfusion map derived from PulseCam compared to camera-only method.
Achieve 2-3 times better resolution compared to camera only method. Needs averaging over only 4x4 pixel block.
(Qualitative): PORH response curve is similar in shape to one obtained using laser Doppler perfusion monitors.

10. PulseCam: Video Demo