Radiology Commons^™

Quantitative Mri And 3d-Printing For Monitoring Periprosthetic Joint Infection, Greg Hong

Electronic Thesis and Dissertation Repository

Joint replacements are becoming increasingly commonplace with over 130,000 joint arthroplasties being performed annually in Canada. Although joint replacement surgery is highly successful, implants do occasionally fail and need to be replaced via costly and difficult revision surgery. Periprosthetic joint infection (PJI) has recently become the leading reason for revision of both hip and knee replacements, which is unfortunate because PJI is difficult to diagnose and treat effectively; diagnosis is made particularly difficult by the lack of established non-invasive (imaging) means of evaluating PJI. This thesis aims to demonstrate that magnetic resonance imaging (MRI) has potential for diagnosing and monitoring …

The Natural History Of Modic Changes - A 5- And 15-Year Follow-Up Study, Parnian Saremi

Electronic Thesis and Dissertation Repository

Modic changes (MCs), defined as bone marrow lesions adjacent to the vertebral endplate seen on MRI, have been associated with back pain. There are different types of MCs, with different histopathological correlates. This community-based study sample comprised 110 men from the Twin Spine Study, with baseline, 5-year, and 15-year follow-up MRIs. Following training and reliability testing, 1320 endplates (T12-S1) were evaluated for MC presence, type, and dimensions at each time point. Results demonstrated that Type 2 Modic Changes (MC2) were the most common type, with approximately half located at the two lowest disc levels. However, Type 1 Modic Changes (MC1) …

Performance Evaluation Of Material Decomposition Using Rapid Kvp-Switching Dual-Energy Ct For Assessing Bone Mineral Density, John M. Wait

Dissertations & Theses (Open Access)

Osteoporosis is diagnosed by assessing the bone mineral density (BMD) of the trabecular bone, and has previously been characterized with dual-energy x-ray absorptiometry (DXA) or single-energy computed tomography (SECT). Dual-energy computed tomography (DECT) is able to create two three-dimensional sets of images representing the densities of two materials in a given basis pair. DECT is theoretically capable of providing a true density measurement of trabecular bone material with the proper material basis pair.

Using the rapid kVp-switching GE HD750 scanner, the concentrations of various solutes were assessed in two-material syringe-phantoms in different experimental conditions with DECT material density images, SECT …