Yuling Yan, Ph.D.
Consulting Assistant Professor
Stanford University School of Medicine
Contact: (650) 725-6500
Fax: (650) 725-8502
Yuling Yan received the Ph.D. degree in mechanical engineering from Keio University, Yokohama, Japan, in 1991. She held post-doctoral fellow and research associate positions in McGill University, Montreal, Canada and Max Planck Institute for Biochemistry, Munich, Germany from 1992-1996 where she worked on the development of quantitative image and signal analysis methods for dynamic mechanical and bimolecular systems. From 1997~1999, she served on the engineering faculty at the University of the Ryukyus, Okinawa, Japan, where she initiated research in a new area on robotic control of dexterous manipulators. She moved to the US in 1999 and while at University of Wisconsin-Madison she collaborated with Dr. Diane Bless on high-speed digital imaging (HSDI) of the voice production. This period led to the development of novel methods and analytical platform for the processing of HSDI images and the analysis of vocal fold vibrations that delivers useful clinical information in a comprehensive, clinician/physician friendly manner. Dr. Yan was an assistant professor of engineering at University of Hawaii–Manoa from 2002-2005 and was awarded an NSF grant (2004~2007) for her research on the technology development and application of HSDI.
Dr. Yan’s current research focuses on basic and translational aspects of voice research including the development of new imaging modalities to study vocal fold dynamics and function with associated approaches for the analysis and modeling of voice production in normal and diseased conditions. Her primary research interests center on the following areas:
- High-speed digital imaging of the larynx
- Functional image and acoustic analysis and modeling of voice production in health and diseased states
- Development and applications of virtual laryngoscopy in clinical settings
- Development of optical approaches to study the biomechanics of the extracellular matrix and connective tissues of the vocal folds
- Non-invasive, intra-vital imaging of laryngeal physiology
Medial Coverage:
- National News (http://www.news14charlotte.com/content/health/?ArID=93693&SecID=26)
- Ivanhoe Broadcasting Corp: National scientific news (http://www.10news.com/health/4460297/detail.html)
- University of Hawai`i Press Office (http://www.hawaii.edu/cgi-bin/uhnews?20040507143321)
- Malamalama: Oficial magazine of the University of Hawai`i (http://www.hawaii.edu/malamalama/2004/09/f4_yan.html)
- Honolulu Star Bulletin (http://starbulletin.com/2004/05/27/news/story9.html)
Research Funding
- NSF award, Division of Bioengineering and Environmental Systems (#BS 0402439). July 1, 2004 – June 30, 2007. “Develop new analytical tools for high-speed laryngeal imaging in clinical applications"
- Subcontractor; Tripler Army Medical Center, Honolulu. (2005).
- Hawaii State Biomedical Research Infrastructure Network (HS-BRIN) grant (2003).
- Seed Money, College of Engineering, University of Hawaii-Manoa (2003).
- Co-PI on an NIH R01 grant (Dec.1, 2002-Nov.30, 2006); “Molecular basis of cardiac muscle contraction ” (PI: Gerard Marriott, University of Wisconsin Medical School)
Research Programs:
High Speed Digital Imaging (HSDI) and Functional Analysis and Modeling of Voice Production in Health and Diseased States
The long term objective of our research program is to establish the mechanism underlying phonation in normal and pathological voice conditions. Vibration of the vocal folds is an essential dynamic event in voice production – our studies are designed to understand specific voice disorders associated with aging and neurological disease in terms of changes in the dynamic properties of the vocal folds. HSDI devices together with simultaneous acoustic recordings are used to monitor the vocal fold vibrations. These techniques are integrated with new methods and global analytic frameworks emerging from our NSF-funded program to analyze laryngeal dynamics and function and to assist in the diagnosis of voice pathologies associated with aging and neurological disease (e.g. Parkinson's disease).
“Develop new analytical tools for high-speed laryngeal imaging in clinical applications” (Funded by NSF; 07/01/ 04 – 06/ 30 / 07)
We are developing new methods and software platforms for comprehensive, functional analysis of vocal fold vibration s that are clinician/physician-friendly and are rich in quantitative parameters for the assessment of voice . These analyses will be used to implement an internet-based, comprehensive, comparative database of dynamic characteristics of vocal folds that correlate with laryngeal health conditions. The database can be used for on-line clinical diagnoses and for training voice researchers, clinicians and medical students. Overall, these studies aim to advance our understanding of vocal mechanism, establish clinical protocols for the differential diagnosis of voice disorders in neurological diseases including Parkinson's and during the aging process, and eventually lead to the emergence of high-speed digital imaging devices for real-time endoscopic examination of patients and on-line analyses at remote sites using telemedicine communication.
“Functional modeling and analysis of human voice in normal and diseased states” (NIH R01 grant application; Pending)
These studies are designed to advance our understandings of voice disorders specifically associated with aging and neurologic disease in terms of changes in the dynamic behavior and characteristics of the vocal folds. We are testing two inter-related hypotheses: First, that specific dynamic properties of the vocal fold vibration change during aging and the progression of neurologic disease; Second, that changes in specific quantitative measures of vocal fold vibrations correlate with voice quality and the severity of the diseased state. These studies include a translational research component that involves validating robust measures of vocal fold dynamics for clinical assessment and diagnosis of age and neurologic-related voice disorders. The proposed research is a collaborative theoretical, experimental and clinical effort that brings together expertise and principles from biomedical engineering, computer science and medicine, and will lead to new approaches for early, voice-based diagnoses of neurological disorders and to improvement on our understanding of how aging affects the human voice.
Image Analysis as a Tool for Disease Proteomics (National Institutes of Health; 12/1/02 ~ 11/30/06; Co-PI) (PI: Gerard Marriott, Dept. Physiology, University of Wisconsin-Madison)
We are applying biophotonics technologies and image analyses to study functional properties of the calcium regulated actomyosin thin filament. These studies involve characterizing nanoscale motions of thin filament proteins using FRET image microscopy, fluorescence polarization image microscopy and digital signal analysis with image processing techniques. Image analysis of proximity and molecular orientation in proteins within single thin filament function are being used to understand the molecular basis of muscle contraction in health and diseased states.
Development of Virtual Laryngoscopy for Clinical Applications (NIH R21 proposal in preparation)
We are developing virtual endoscopes for 3D visualization, and non-invasive diagnosis - current efforts are focused on developing a virtual laryngoscope system for sub-glottal visualization, diagnosis of laryngeal and airway disorders.The goal of these studies is to extend and merge endoscopic examinations of patients and virtual endoscopy for better clinical diagnoses and treatments of diseases of the vocal system.
Optical Studies on the Biomechanics of Extracellular Matrix and Connective Tissues and its Role in Laryngeal Function
We are developing new biochemical and fluorescence-based imaging techniques for:
- Microviscocity measurements of the extracellular matrix of the vocal folds;
- Studies of the effects of hydration on mucus viscosity and vocal fold function;
- Studies on the physical and biomechanical properties of connective tissue layers (collagen and elastin) of the larynx
These optical studies are designed to provide a quantitative understanding of how biomechanical properties of the vocal folds and vocal function are affected by known modulators of elastin function (e.g. smoking) and increased cross-linking of collagen during natural aging.
Non-invasive, Intravital Imaging of Laryngeal Physiology
We are exploring the application of new imaging modalities to assess how specific molecular, cellular and physiological components of the human vocal system contribute to the biomechanical properties and function of the larynx. These studies focus on the imaging and analysis of muscle contraction as it relates to laryngeal function in normal condition, during the aging process and for neurologic voice disorders.
Endoscope imaging provides valuable information on laryngeal dynamics that we hypothesize are correlated with voice quality and health condition. However patient discomfort constitutes a major limitation of endoscope based examinations. We are developing non-invasive imaging modalities to study laryngeal physiology and function during unconstrained phonation. Our approaches include non-invasive or endoscope based imaging and measurement of oxygenation/deoxygenation, blood flow (NIR absorption 720/760 nm) and muscle contraction measured through NIR illumination.
