Research Projects in OIL@OSU

 

(Updated on Dec. 17, 2013)                                                                                                      Return

 

Active projects and projects of interest

 

1.     Transduodenal diffuse optical tomography of pancreas

 

2.     Transrectal diffuse optical tomography of prostate

 

3.     Endoscopic diffuse optical tomography and fluorescence-enhanced diffuse optical tomography

 

4.     Percutaneous single fiber reflectance spectroscopy

 

5.     Low coherence interferometry and optical coherence tomography

 

6.     Dynamic thermography for assessing tissue perfusion dynamics

 

7.     Analytical and numerical modeling of photon propagation

 

8.     Magnetothermoacoustics

 

 

To potential applicants:

 

Our research works are highly experimental and involve live subjects, as the general objectives of our research are to test a translational hypothesis or to address a surgically or diagnostically relevant issue.

 

We acquire material and instrument that are available and affordable, and fabricate/devise the rest. Some of our previous and current members of the lab especially enjoy the hands-on part: conceiving and building from the scratch, respecting and operating the machinery, expecting and observing the phenomena that deepen our understanding of norms and abnormalities, and making the new knowledge applicable to clinics for the reduction of burden by disease.

 

More specifically, the members of our lab are intellectually curious about the following aspects:

 

(1)   Experimental development involving fiber optics, acoustics, magnetics, etc. for sensing and imaging.

(2)   Spectroscopic analysis to reconstruct tissue components of physiological relevance and diagnostic contrast.   

(3)   Computational algorithm for improving image reconstruction in the broad field of biomedical optics and bio-photonics.

(4)   Theoretical modeling regarding propagation of light or sound of different temporal and spectral characteristics in biological tissue.  

 

We are particularly interested in candidates who are hands-on: build the things needed to solve a problem identified.  

 

If you want to contact Dr. Piao for potential research opportunities, please include in your initial inquiry your CV and a statement of how your background may be valuable to the research in this lab. 

 

 

 

 

 

 

The following project descriptions are not up-to-date.  

 

1. Trans-rectal near-infrared optical tomography for prostate imaging  

 

The objective of this research is to explore the technology of transrectal near-infrared (NIR) optical tomography for accurate, selective prostate biopsy.
 
Prostate cancer is the most common non-dermatologic cancer in American men, with an estimate of 237,700 new cases in 2006. Prostate cancer suspicion 
is typically based on an elevated serum prostate-specific antigen (PSA) level or a suspicious nodule found during a digital rectal exam (DRE). Palpation is 
subjective, insensitive, and inexact, and more than half of all cancers detected today are not palpable. PSA can be an indicator of prostate cancer; however, 
it is not a specific indicator of malignancy or of tumor recurrence after treatment (with the exception of radical prostatectomy). When the PSA level is 
elevated or the DRE is abnormal, there is a 25 % chance that cancer is present. This can only be confirmed by a needle biopsy that is guided by trans-rectal 
ultrasound (TRUS). Since there are no pathognomonic findings for prostate cancer on ultrasound imaging, random biopsies are taken throughout the prostate.  
The accuracy of biopsy is problematic and many men undergo multiple biopsies. 
 
Pathologic studies have demonstrated increased vasculature associated with prostate cancer, as well as a positive correlation between microvessel density and 
the aggressiveness of disease. An accurate non-invasive imaging examination that is sensitive to the elevated vasculature could present images with high 
contrast, thus improve the biopsy outcome substantially. Such an imaging technique could also be invaluable for accurate non-invasive assessment of patients 
undergoing radiation treatment for their prostate cancer. Near-infrared (NIR) optical tomography has been demonstrated to provide extremely high 
vascular-based contrast in cancer detection, and to manifest high sensitivity in monitoring cancer treatment in breast cancer. NIR optical tomography can be 
applied as stand-alone technique or in combination with ultrasound to evaluate the prostate, where as seen in breast cancer, it has a strong potential for 
identifying hypervascularity of areas in the prostate.  These areas could then be selectively biopsied to improve the detection of prostate cancer. 
 
NIR optical tomography could be used as a stand-alone modality to provide blood-based contrast, or a combination with the conventional TRUS to offer both 
the contrast and anatomy information. The proposed research will be carried out by a joint team consisting of biomedical optical scientists in in OSU Electrical 
& Computer Engineering, veterinary clinical scientists in OSU Vet-Med College, urologic oncologists in University of Oklahoma Health Science Center, and 
computational electromagnetic scientist in OSU Electrical & Computer Engineering.
 
Hypothesis:
(1) NIR tomography can image through rectum to a depth of several millimeters up to over a centimeter, providing transrectal tomography of posterior prostate tissue
(2) High tumor-tissue contrast in prostate can be provided by transrectal NIR tomography, as a result of the elevation of the vascular densities in prostate cancer.
 
left3.tif                      3d_mesh
                      NIR_US_probe_15
 
The images at the left are the first set of in vivo measurements taken from a healthy dog prostate by use of concurrent trans-rectal near-infrared and trans-rectal ultrasound 
techniques. The technique will ultimately enable imaging of prostate cancer as shown in the 3-D figure at the upper right by integrated trans-rectal NIR/US probe such as 
the one shown at the lower right.  

 

mua_mus_mueff_data_2.tif

 

Trans-rectal NIR/US of normal canine prostate in vivo: The US and NIR images were taken at the right lobe (left column), middle-line (middle column), and the left lobe (right column). The 1st row, US; the 2nd row, coronal view of the locations of sagittal NIR/US planes; the 3rd row, absorption coefficient; the 4th row, transport scattering coefficient; the 5th row, effective attenuation coefficient; the 6th row, axial view of the locations of sagittal NIR/US planes. The dimensions of all images are 50mm´30mm (cranial-caudal ´ dorsal-ventral). BL-urinary bladder, PR-prostate.

 

 

 

 

In vivo trans-rectal NIR/US of TVT development in canine pelvic canal. The images were taken before the TVT injection, 14 days after the TVT injection when the US and rectal examination showed no evidence of tumor growth, and 35 days after the TVT injection when the tumor growth was evident on both US and rectal examination. (a) US and NIR absorption images. (b) US and NIR reduced scattering images. The dimensions of the images are 60´30 mm2 (cranial-caudal´dorsal-ventral). The rectangular mark enclosing L1 is used in Fig. 2(a), where the peak

NIR contrasts within the region are plotted. NT: needle track.

 

 

 

2. Hemodynamic imaging of internal organs by endoscopic near-infrared optical tomography

                        Endoscopic NIR tomography of  local absorption change--------------NIR-DOT at small scale

 

Near-infrared (NIR) optical tomography is a non-invasive diagnostic imaging technique that has the potential of acquiring unique tissue-specific contrast. The high contrast

of NIR optical tomography originates from the stronger light attenuation by hemoglobin relative to water in parenchymal tissue, as well as the distinct spectral differences

of hemoglobin between the oxygenated and deoxygenated states. Contrast as high as ~300% has been demonstrated in NIR tomography for vascular densities of 2%, due

to increased vascularity in malignant tissues. Such high blood-based contrast means that pathognomic diagnosis for cancer detection and hemodynamic imaging are quite

feasible. Over the past two decades, NIR optical tomography has advanced steadily by finding key applications in characterization of breast cancer, assessment of brain

functionality, and evaluation of extremity abnormality, etc. All these applications have focused on using external applicator arrays, yet it is feasible to extend this approach

to endoscopy geometries for imaging internal organs such as prostate, colon and rectum. The key factor in attempting NIR tomography of internal organs has been the

development of appropriate applicator arrays.

 

Recently a novel applicator array was constructed and a NIR optical tomography system that allows 2-dimensional NIR contrast mapping of internal organs via endoscopic

interrogation was demonstrated. This innovative technique presents a new paradigm for non-invasive tissue-specific cancer detection in internal organs including, but not

limited to, prostate, colon-rectum, and cervix.

 

 

 3. Diffuse Optical Tomography

Video-rate near-infrared diffuse optical tomography

                               Moving object

                               “Snapshot” of local absorption change

 

4. Optical Coherence Tomography (OCT)

What is optical coherence tomography

Long-coherence source

Non-coherent source

Low-coherence source

--------------Catheter-based OCT