Friday, October 16th, 2015

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
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.