Rapid, High-Resolution, and Signal-Efficient Methods for the Clinical Translation of Bone Magnetic Resonance Imaging Brian-Tinh Duc Vu

Format:

Book

Thesis/Dissertation

Author/Creator:

Vu, Brian-Tinh Duc, author.

Contributor:

University of Pennsylvania. Bioengineering., degree granting institution.

Language:

English

Subjects (All):

0215.

0364.

0541.

0574.

Local Subjects:

0215.

0364.

0541.

0574.

Physical Description:

1 electronic resource (182 pages)

Contained In:

Dissertations Abstracts International 87-07B

Place of Publication:

Ann Arbor : ProQuest Dissertations and Theses, 2025

Language Note:

English

Summary:

Conventional magnetic resonance imaging (MRI) techniques emphasize the assessment of anatomical soft tissues. However, MR imaging of solid structures, like bone, may offer clinical utility. Unlike computed tomography (CT), MRI obviates the use of ionizing radiation and may perform spatial encoding with arbitrary orientation. Moreover, solid-state MRI techniques, methods which measure the MR signal of rapidly decaying solid tissues, can directly assess the structure of and signal specific to cortical bone.Many MR techniques for imaging trabecular and cortical bone have been developed. However, their clinical translation is hindered by their longer scan durations, which are, in part, functions of the lower signal-to-noise ratio (SNR) conditions encountered in bone MRI. In this dissertation, we propose methods to bring two bone imaging applications closer to clinical use. First, the ultra-high-resolution imaging (<500 µm) of trabecular bone visualizes the marrow lying between trabecular elements. From these images, biomarkers of trabecular bone remodeling may be observed and used to track the longitudinal efficacy of bone-strengthening treatment or osteoporotic progression. We leverage advanced image reconstruction techniques to enable the rapid assessment of the trabecular compartment with minimal loss in trabecular bone image quality. Second, solid-state techniques may be used to create MR images which emulate the bone-selective property of a CT image. These techniques capture and isolate the rapidly decaying signal of water protons bound to the collagen matrix in bone. This bound water signal is typically inaccessible to conventional MRI methods. When optimized, solid-state techniques may offer a non-radiative alternative to head CT for structural bone imaging in pediatric patients. Finally, an MRI method is proposed to simultaneously acquire solid- and multiple soft-tissue contrasts in a single scan. The proposed pulse sequence, DREAMER (Dual Repetition and Echo Acquisition with Multi-contrast Encoding and Reconstruction), combines a dual-echo ultrashort echo sequence typically used for solid-state imaging with a predetermined radiofrequency pulse phase schedule. Long- and short-T2 signals are encoded in the relative magnitudes and phases of the acquired steady-state MR signal. A single DREAMER acquisition results in bone-selective, T1-weighted, and T2-weighted images which are self-registered and isotropic in resolution without additional post-processing

Notes:

Advisors: Rajapakse, Chamith S. Committee members: Wehrli, Felix W.; Song, Hee Kwon; Witschey, Walter R.

Source: Dissertations Abstracts International, Volume: 87-07, Section: B.

Ph.D. University of Pennsylvania 2025

Vendor supplied data

Local Notes:

School code: 0175

ISBN:

9798276007519

Access Restriction:

Restricted for use by site license