BME Seminar Friday, October 16th, 2015 UTEB 150 at Storrs & Videoconferenced to UCHC CG-079B 12:00-12:50 pm *Refreshments will be served* “Characterization of high resolution quantitative optical properties of biological tissues using spatial frequency domain imaging (SFDI)” Presented by: Sreyankar Nandy, PhD student, Biomedical Engineering Dept., Univ. of Connecticut. Advisor: Prof. Quing Zhu Abstract: Conventional high resolution imaging modalities e.g. wide field microscopy, fluorescence imaging, coherent imaging methods are limited by the lack of quantitative information of biological tissues. These methods are also complicated and expensive in setup and hence not readily portable or integrable in the operating room for physicians’ diagnosis. Spatial frequency domain imaging (SFDI) is an emerging imaging modality which can provide high resolution optical property maps e.g. absorption, scattering, blood oxygenation etc. with high degree of accuracy. This method combines the quantitative methods of Diffuse Optical Imaging (DOI) and the high resolution wide field structured light imaging. Initial ex vivo studies on benign and malignant human ovarian tissues have provided promising results. SFDI can be used as an effective in vivo guidance tool for surgeons during image guided surgery, hence reducing the risk and complications associated with unnecessary surgeries and improve the quality of life of the patients. Bio: Sreyankar Nandy received his MS in Applied Physics from IIEST, India and MTech in Applied Optics from Indian Institute of Technology (IIT), Delhi. He is currently a PhD student working with Prof Quing Zhu in the Optical and Ultrasound Imaging Lab at UConn. His area of interest is optical elastography and tissue biomechanics, photoacoustic imaging and diffuse optical imaging of biological tissues. “Improvement and evaluation of a low-cost laser diode photoacoustic microscopy system for ovarian tissue imaging” Presented by: Mohsen Erfanzadeh, PhD student, Biomedical Engineering Dept, Univ. of Connecticut Advisor: Prof. Quing Zhu Abstract: Photoacoustic microscopy (PAM) is capable of imaging tumor angiogenesis. Clinical applications of PAM are limited due to the use of expensive and bulky pulsed laser sources. High power pulsed laser diodes (PLD) can be suitable substitute light sources for PAM. Multiple active elements in high power PLDs and intrinsic anisotropy of the PLD beam challenge maintaining low-loss focusing of light for ovarian tissue PAM imaging. Here, a laser diode optical resolution photoacoustic microscopy (LD-OR-PAM) system that utilizes a 905 nm, 650 W output peak power PLD and a low-loss optical setup is evaluated for imaging ovarian tissues. A combination of aspheric and cylindrical lenses is successfully used for low-loss collimation and focusing of light. The lateral resolution is measured to be 40 µm using edge spread function estimation. PAM images of black human hairs, polyethylene tubes filled with rat blood, ex-vivo mouse ear, and ex-vivo porcine ovary are presented. The initial results indicate the great potential of this compact and low-cost system for imaging and characterization of ovarian cancer. Short Bio: Mohsen Erfanzadeh received his BS in Physics from University of Tehran and MSc in PhotonicsBiophotonics from the Laser and Plasma Research Institute of Shahid Beheshti University. He is currently pursuing his PhD in Biomedical Engineering at UConn under Professor Quing Zhu’s supervision. Mohsen’s research interests are optical imaging for cancer diagnosis, Photoacoustic microscopy, Photoacoustic tomography, and development of low-cost, portable, and fast imaging systems. “Smart-phone based monitoring of tidal volume and respiratory rate” Presented by: Bersian Reyes, PhD Candidate, Biomedical Engineering Dept. Univ Connecticut. Advisor Dr. Ki Chon Abstract: Two parameters that a breathing status monitor should provide include tidal volume (V T) and respiration rate (RR). Recently we implemented an optical monitoring approach that tracks chest wall movements directly on a smartphone. In this paper, we explore the use of optical monitoring of chest wall movements to provide not just average RR, but also information about VT and to track RR at each time-instant (IRR). The algorithm, implemented on an Android smartphone, was used to analyze the video information from the smartphone’s camera and provide in real time the chest movement signal from N=15 healthy volunteers breathing at VT ranging from 300 mL to 3 L. Simultaneous recording of volume signals from a spirometer was regarded as reference. A highly linear relationship between peak-to-peak amplitude of the smartphone-acquired chest movement signal and spirometer VT was found (r2=0.951 ± 0.042, mean ± SD). After calibration on a subjectby-subject basis, no statistically-significant bias was found in terms of VT estimation; the 95% limits of agreement were -0.348 to 0.376 L, and the RMSE was 0.182 ± 0.107 L. In terms of IRR estimation, a highly linear relation between smartphone estimates and the spirometer reference was found (r2=0.999 ± 0.002). The bias, 95% limits of agreement, and RMSE were -0.024 bpm, -0.850 to 0.802 bpm, and 0.414 ± 0.178 bpm, respectively. These results showed the feasibility of developing an inexpensive and portable breathing monitor which provides information about IRR as well as VT, when calibrated on an individual basis, which shows promise outside research settings. Bio: Bersain Reyes received the BSc and MSc degrees from the Universidad Autonoma Metropolitana (UAM) in Mexico City, Mexico. His interests related to biomedical signal processing include the analysis of respiratory sounds, time-frequency analysis, and mobile healthcare applications.