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You searched for +publisher:"University of Michigan" +contributor:("Carson, Paul L."). Showing records 1 – 3 of 3 total matches.

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University of Michigan

1. Lei, Hao. Developments and Applications of Laser-Based and X-Ray-Based Biomedical Thermoacoustic Imaging Techniques.

Degree: PhD, Mechanical Engineering, 2019, University of Michigan

Thermoacoustic imaging (TAI) is one class of biomedical imaging techniques that share the same physical basis, called the thermoacoustic effect (TAE). The TAE phenomenon can be categorized as sonic waves generated following the absorption of energy/heat. In recent decades, as a result of the continuous development of radiation sources such as masers and lasers, the TAE phenomenon has been extensively utilized to achieve biomedical imaging. The hybrid modality offers high contrast and spectroscopic-based specificity image with ultrasonic spatial resolution. It shows great potential for preclinical research and clinical practice in achieving anatomical, functional, and molecular images. So far, however, TAI has not been widely adopted in clinic. The major challenges include 1) the limited imaging depth due to the applied radiation and 2) the difficulty in achieving quantitative image. The purpose of this research is to further investigate the fundamental mechanism of TAI and to broaden its applications. In the first part of this study, laser-based TAI technique, also known as photoacoustic (PA) imaging, is implemented to improve the diagnosis of Crohn’s disease, especially solving the challenge of characterizing the intestinal strictures in bowel. The feasibility of assessing the spatially varying molecular components in ex vivo intestinal strictures by obtaining PA molecular component images using a developed acoustic resolution PA microscopy system is validated. Then, the microscopy system is miniaturized to a prototype side-view scanning capsule-shaped probe and its practicability in quantitatively differentiate the intestinal disease conditions is proved by performing in vivo colonoscopy in the rabbit disease model. In the second part of this study, the potential applications of x-ray-based TAI technique, named x-ray induced acoustic (XA) imaging, are evaluated. Based on soft-tissue phantom studies, the feasibility in monitoring the position of the x-ray beam and measuring the spatially varying dose deposition is validated. These results suggested a potential application of XA imaging method as a novel in vivo dosimetric tool in external beam radiotherapy. Furthermore, an XA and ultrasound (US) dual-modality imaging system is established utilizing a commercial ultrasound unit, aiming to obtain XA image and US image simultaneously, both in real time. As demonstrated by the experiments on soft-tissue phantoms, the XA image showing the deposited radiation dose and the US image capturing the motion of target tissue can be naturally co-registered, offering a potential approach for image-guided radiotherapy. Advisors/Committee Members: Ni, Jun (committee member), Wang, Xueding (committee member), Carson, Paul L (committee member), Oldham, Kenn Richard (committee member), Xu, Guan (committee member).

Subjects/Keywords: Thermoacoustic imaging; Photoacoustic imaging; X-ray acoustic imaging; Medical and biological imaging; Ultrasound; Dosimetry; Mechanical Engineering; Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Lei, H. (2019). Developments and Applications of Laser-Based and X-Ray-Based Biomedical Thermoacoustic Imaging Techniques. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/150038

Chicago Manual of Style (16th Edition):

Lei, Hao. “Developments and Applications of Laser-Based and X-Ray-Based Biomedical Thermoacoustic Imaging Techniques.” 2019. Doctoral Dissertation, University of Michigan. Accessed October 23, 2019. http://hdl.handle.net/2027.42/150038.

MLA Handbook (7th Edition):

Lei, Hao. “Developments and Applications of Laser-Based and X-Ray-Based Biomedical Thermoacoustic Imaging Techniques.” 2019. Web. 23 Oct 2019.

Vancouver:

Lei H. Developments and Applications of Laser-Based and X-Ray-Based Biomedical Thermoacoustic Imaging Techniques. [Internet] [Doctoral dissertation]. University of Michigan; 2019. [cited 2019 Oct 23]. Available from: http://hdl.handle.net/2027.42/150038.

Council of Science Editors:

Lei H. Developments and Applications of Laser-Based and X-Ray-Based Biomedical Thermoacoustic Imaging Techniques. [Doctoral Dissertation]. University of Michigan; 2019. Available from: http://hdl.handle.net/2027.42/150038


University of Michigan

2. Green, Crystal. Automated Deformable Mapping Methods to Relate Corresponding Lesions in 3D X-ray and 3D Ultrasound Breast Images.

Degree: PhD, Nuclear Engineering & Radiological Sciences, 2019, University of Michigan

Mammography is the current standard imaging method for detecting breast cancer by using x-rays to produce 2D images of the breast. However, with mammography alone there is difficulty determining whether a lesion is benign or malignant and reduced sensitivity to detecting lesions in dense breasts. Ultrasound imaging used in conjunction with mammography has shown valuable contributions for lesion characterization by differentiating between solid and cystic lesions. Conventional breast ultrasound has high false positive rates; however, it has shown improved abilities to detect lesions in dense breasts. Breast ultrasound is typically performed freehand to produce anterior-to-posterior 2D images in a different geometry (supine) than mammography (upright). This difference in geometries is likely responsible for the finding that at least 10% of the time lesions found in the ultrasound images do not correspond with lesions found in mammograms. To solve this problem additional imaging techniques must be investigated to aid a radiologist in identifying corresponding lesions in the two modalities to ensure early detection of a potential cancer. This dissertation describes and validates automated deformable mapping methods to register and relate corresponding lesions between multi-modality images acquired using 3D mammography (Digital Breast Tomosynthesis (DBT) and dedicated breast Computed Tomography (bCT)) and 3D ultrasound (Automated Breast Ultrasound (ABUS)). The methodology involves the use of finite element modeling and analysis to simulate the differences in compression and breast orientation to better align lesions acquired from images from these modalities. Preliminary studies were performed using several multimodality compressible breast phantoms to determine breast lesion registrations between: i) cranio-caudal (CC) and mediolateral oblique (MLO) DBT views and ABUS, ii) simulated bCT and DBT (CC and MLO views), and iii) simulated bCT and ABUS. Distances between the centers of masses, dCOM, of corresponding lesions were used to assess the deformable mapping method. These phantom studies showed the potential to apply this technique for real breast lesions with mean dCOM registration values as low as 4.9 ± 2.4 mm for DBT (CC view) mapped to ABUS, 9.3 ± 2.8 mm for DBT (MLO view) mapped to ABUS, 4.8 ± 2.4 mm for bCT mapped to ABUS, 5.0 ± 2.2 mm for bCT mapped to DBT (CC view), and 4.7 ± 2.5 mm for bCT mapped to DBT (MLO view). All of the phantom studies showed that using external fiducial markers helped improve the registration capability of the deformable mapping algorithm. An IRB-approved proof-of-concept study was performed with patient volunteers to validate the deformable registration method on 5 patient datasets with a total of up to 7 lesions for DBT (CC and MLO views) to ABUS registration. Resulting dCOM’s using the deformable method showed statistically significant improvements over rigid registration techniques with a mean dCOM of 11.6 ± 5.3 mm for DBT (CC view) mapped to ABUS and a mean dCOM of 12.3 ± 4.8 mm… Advisors/Committee Members: Bielajew, Alex F (committee member), Goodsitt, Mitchell M (committee member), Carson, Paul L (committee member), Brock, Kristy K (committee member), Matuszak, Martha M (committee member).

Subjects/Keywords: deformable registration; multi-modality breast imaging; biomechanical modeling; digital breast tomosynthesis; automated breast ultrasound; Nuclear Engineering and Radiological Sciences; Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Green, C. (2019). Automated Deformable Mapping Methods to Relate Corresponding Lesions in 3D X-ray and 3D Ultrasound Breast Images. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/150042

Chicago Manual of Style (16th Edition):

Green, Crystal. “Automated Deformable Mapping Methods to Relate Corresponding Lesions in 3D X-ray and 3D Ultrasound Breast Images.” 2019. Doctoral Dissertation, University of Michigan. Accessed October 23, 2019. http://hdl.handle.net/2027.42/150042.

MLA Handbook (7th Edition):

Green, Crystal. “Automated Deformable Mapping Methods to Relate Corresponding Lesions in 3D X-ray and 3D Ultrasound Breast Images.” 2019. Web. 23 Oct 2019.

Vancouver:

Green C. Automated Deformable Mapping Methods to Relate Corresponding Lesions in 3D X-ray and 3D Ultrasound Breast Images. [Internet] [Doctoral dissertation]. University of Michigan; 2019. [cited 2019 Oct 23]. Available from: http://hdl.handle.net/2027.42/150042.

Council of Science Editors:

Green C. Automated Deformable Mapping Methods to Relate Corresponding Lesions in 3D X-ray and 3D Ultrasound Breast Images. [Doctoral Dissertation]. University of Michigan; 2019. Available from: http://hdl.handle.net/2027.42/150042

3. Jintamethasawat, Rungroj. Limited Angle Ultrasound Tomography of the Compressed Breast.

Degree: PhD, Biomedical Engineering, 2018, University of Michigan

X-ray mammography is widely accepted as the clinical standard for breast cancer screening and diagnosis. However, reflection mode ultrasound has been known to outperform x-ray in screening performance in dense breasts. With newer modes of ultrasound, acoustic properties of breast tissue, such as the speed of sound and attenuation coefficient distributions, can be extracted from captured ultrasound signals and used to characterize breast tissue types and contribute to detection and diagnosis of malignancy. The same is possibly true for optical absorption via photoacoustic imaging. Recently, we have developed a dual-sided ultrasound scanner that can be integrated with existing x-ray mammographic systems and acquire images in the mammographic view and compression. Transmission imaging for speed of sound and attenuation coefficient in this geometry is termed limited angle tomography, as the beams at frequencies yielding high resolution cannot transit the long axis of the compressed breast. This approach, ideally, should facilitate the co-registration and comparisons between images from three modalities discussed here (x-ray, ultrasound and photoacoustic) and increase diagnostic detection confidence. However, potential limitations inherent in limited angle tomography have received minimal exploration up to this study, and existing imaging techniques developed for this approach are based on overly optimistic assumptions that hinder achievement of the desired image quality. This investigation of these problems should contribute valuable information to the validation and translation of the mammographically-configured, dual-sided ultrasound, or ultrasound and photoacoustic, scanner to the clinic. This dissertation first aims to extensively identify possible sources of error resulting from imaging in the limited angle tomography approach. Simulation findings mapping parametric conditions reveal that image artifacts arising in reflection mode (B-mode) can be modulated or mitigated by ultrasound gels with adequate acoustic properties. In addition, sound speed imaging was performed determining the level of significance for several key sources of error. Results suggest that imaging in transmission mode is the most sensitive to transducer misplacement in the signal propagation direction. This misplacement, however, could be minimized easily by routinely calibrating transducer positions. Next, this dissertation aims to advance speed of sound, attenuation, and photoacoustic image reconstruction algorithms for the limited angle tomography approach. This was done by utilizing both structural information of the imaged objects/tissues by means of the corresponding reflection mode images taken from the same imaging location, and a full acoustic modeling framework to account for complex acoustic interactions within the field of view. We have shown through simulations that both a priori information from reflection mode images and full acoustic modeling contribute to a noticeable improvement in the reconstructed images. Work done… Advisors/Committee Members: Kripfgans, Oliver Daniel (committee member), Wang, Xueding (committee member), Wenisch, Thomas F (committee member), Carson, Paul L (committee member), Fessler, Jeffrey A (committee member).

Subjects/Keywords: ultrasound tomography; breast imaging; Biomedical Engineering; Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Jintamethasawat, R. (2018). Limited Angle Ultrasound Tomography of the Compressed Breast. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/143944

Chicago Manual of Style (16th Edition):

Jintamethasawat, Rungroj. “Limited Angle Ultrasound Tomography of the Compressed Breast.” 2018. Doctoral Dissertation, University of Michigan. Accessed October 23, 2019. http://hdl.handle.net/2027.42/143944.

MLA Handbook (7th Edition):

Jintamethasawat, Rungroj. “Limited Angle Ultrasound Tomography of the Compressed Breast.” 2018. Web. 23 Oct 2019.

Vancouver:

Jintamethasawat R. Limited Angle Ultrasound Tomography of the Compressed Breast. [Internet] [Doctoral dissertation]. University of Michigan; 2018. [cited 2019 Oct 23]. Available from: http://hdl.handle.net/2027.42/143944.

Council of Science Editors:

Jintamethasawat R. Limited Angle Ultrasound Tomography of the Compressed Breast. [Doctoral Dissertation]. University of Michigan; 2018. Available from: http://hdl.handle.net/2027.42/143944

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