Accurate evaluation of morphological changes in articular cartilage are necessary for early detection of osteoarthritis (OA). 3T magnetic resonance imaging (MRI) has highly sensitive contrast ...resolution and is widely used clinically to detect OA. However, synchrotron radiation phase-contrast imaging computed tomography (SR-PCI) can also provide contrast to tissue interfaces that do not have sufficient absorption differences, with the added benefit of very high spatial resolution. Here, MRI was compared with SR-PCI for quantitative evaluation of human articular cartilage. Medial tibial condyles were harvested from non-OA donors and from OA patients receiving knee replacement surgery. Both imaging methods revealed that average cartilage thickness and cartilage volume were significantly reduced in the OA group, compared to the non-OA group. When comparing modalities, the superior resolution of SR-PCI enabled more precise mapping of the cartilage surface relative to MRI. As a result, MRI showed significantly higher average cartilage thickness and cartilage volume, compared to SR-PCI. These data highlight the potential for high-resolution imaging of articular cartilage using SR-PCI as a solution for early OA diagnosis. Recognizing current limitations of using a synchrotron for clinical imaging, we discuss its nascent utility for preclinical models, particularly longitudinal studies of live animal models of OA.
We report an unusual case of chronic mesenteric ischemia presenting in a 12-year-old girl with idiopathic infantile arterial calcinosis (IIAC). This is the first reported case in the literature of ...chronic mesenteric ischemia in the setting of IIAC. The girl presented with a classical history of postprandial abdominal pain. Imaging demonstrated significant stenoses of the celiac axis, superior mesenteric artery (SMA) and inferior mesenteric artery (IMA). Angioplasty of the celiac axis and SMA was attempted, with successful dilation of the SMA only. At 3-, 6- and 12-month follow-ups, the child’s symptoms had almost resolved. This case report has three important ramifications: chronic mesenteric ischemia is a possible clinical presentation in children with IACC, pre-angioplasty imaging is important in guiding treatment approach, and angioplasty was effective in this case of chronic mesenteric ischemia and offers hope for other similarly affected children.
The superior mesenteric vein (SMV) is left of the superior mesenteric artery (SMA), consistent with nonrotation (Figure 1). Consequently, the bowel is distributed unusually, and difficult to follow ...in its entirety. In the left aspect of the midabdomen, a dilated loop of small bowel shows an abrupt calibre change, and appears to fold onto itself (Figure 2). Moreover, the involved segment of small bowel enhances to a lesser extent than the adjacent normal bowel. Further images reveal stretching and clustering of mesenteric vessels at the hernia orifice, beak-like tapering of the small bowel as it herniates through the defect, and distal small-bowel decompression (Figures 3-5). Surgical findings confirm the suspicion of ischemic small bowel incarcerated within an internal (omental) hernia. The rapid development of ischemia is attributable to associated volvulus. This was suspected clinically, given the elevated serum lactate levels.
Survivors of childhood Wilms tumors are at an increased risk of second malignant neoplasms. Recently, it has been postulated that renal cell carcinoma is among the malignancies for which this ...population is at risk. We present the unique case of an adult Wilms tumor survivor with non-syndromic hemihypertrophy (NSHH) who developed renal cell carcinoma. This case highlights the need for close follow-up in two populations: adults who have survived Wilms tumor and those with NSHH.
The purpose of this pilot study was to evaluate lymph node enhancement with an indirect magnetic resonance (MR) lymphography technique using 2 different contrast agents in the head and neck region of ...healthy dogs. Five dogs were imaged at various times after intradermal injection of gadoversetamide and Gadofluorine M (minimum of 1 week apart) in the right and left mandibular, temporal, and lateral neck regions. We observed consistent progressive enhancement with time in the mandibular, retropharyngeal, and superficial cervical lymph nodes. The node enhancement was comparable for both contrast agents. Contrast enhancement of the parotid lymph nodes was not seen. We conclude that this technique of indirect MR lymphography using either agent could be used to identify those lymph nodes at highest risk of metastatic disease in dogs with cancer, and to guide staging and treatment.
Glioblastoma multiforme (GBM) is one of the most malignant human tumors, with a uniformly poor outcome. One obstacle in curing malignant brain tumors is the limitation of conventional light ...microscopy in detecting microscopic residual tumor in biopsy samples from the perimeter of the surgically resected tumor. We further refined the identification of GBM tumor tissue at the sub-cellular level, utilising the technique of Synchrotron, sourced mid-infrared (mid-IR) spectromicroscopy. Paired, thin (5 microm) cryosections of snap-frozen human GBM tumor samples removed at elective surgery were mounted on glass slides (hematoxylin and eosin-stained tissue section) and calcium fluoride (CaF2) windows (unstained tissue section for transmission spectromicroscopy), respectively. Concordance of tumor bearing areas identified in the stained section with the unstained IR tissue section was confirmed by the pathologist of the study. Compared with molecular signatures obtained from normal control brain tissue, unique spectroscopic patterns were detected in GBM tumor samples from 6 patients. The identifying features of GBM were: i) high protein-to-lipid ratios (amide I+II/CH2 symmetric stretch; amide I+II/CH2+CH3 symmetric and asymmetric stretch), and ii) considerable enhancement of the intensities of characteristic peaks at 2,957 and 2,871 cm(-1) representing CH3 asymmetric and symmetric stretch, respectively. Spectral data sets were subjected to Ward's algorithm for assignment to similar groups, and then subjected to hierarchical cluster analysis (HCA) by means of false color digital maps. False color images of 5 clusters obtained by HCA identified dominant clusters corresponding to tumor tissue. Corroboration of these findings in a larger number of GBM may allow for more precise identification of these and other types of brain tumors.
The Biomedical Imaging and Therapy (BMIT) beamlines at the Canadian Light Source (CLS) comprise a multi-modality synchrotron imaging facility capable of imaging objects with 2-200 μm resolution with ...beam sizes up to ~200 mm wide and ~10 mm high in the experimental hutches 1-3. BMIT hosts two beamlines, a bend magnet 05B1-1 and an insertion device 05ID-2, with capabilities to apply absorption imaging, in-line phase contrast imaging (PCI), analyzer-based imaging (ABI) or diffraction-enhanced imaging (DEI), and K-Edge Subtraction (KES) imaging. Talbot or grating interferometry is under development.
Biomedical research at synchrotron facilities may involve imaging live animals that must remain motionless for extended periods of time to obtain quality images. Even breathing movements reduce image ...quality but on the other hand excessive restraint of animals increases morbidity and mortality. We describe a humane animal restraint designed to eliminate head movements while promoting animal survival.
This paper describes how an animal restraint that conforms to the shape of an animal's head was fabricated by a 3D prototyper. The method used to translate medical computed tomography (CT) data to a 3D stereolithography format is described and images of its use at the Canadian Light Source (CLS) are shown. This type of restraint holds great promise in improving image quality and repeatability while reducing stress on experimental animals.
In our pediatric interventional practice, we have found that occasionally a loop of bowel is interposed between the stomach and the anterior wall of the abdomen, preventing safe needle access for ...procedures such as placement of a gastrostomy tube. The use of a small-caliber needle to aspirate air from the colon or small bowel, for bowel decompression, may be a safe way to aid in establishing a safe access route for the subsequent percutaneous introduction of larger needles or tubes.
Our retrospective review of patients who have undergone bowel-gas aspiration during an interventional procedure shows that the aspiration of air from the colon with a small-caliber needle is technically easy and may permit completion of an abdominal procedure.
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