Diagnostic errors in musculoskeletal oncology and possible mitigation strategies.

The objective of this paper is to explore sources of diagnostic error in musculoskeletal oncology and potential strategies for mitigating them using case examples. As musculoskeletal tumors are often obvious, the diagnostic errors in musculoskeletal oncology are frequently cognitive. In our experience, the most encountered cognitive biases in musculoskeletal oncologic imaging are as follows: (1) anchoring bias, (2) premature closure, (3) hindsight bias, (4) availability bias, and (5) alliterative bias.

MR Imaging Knee Synovitis and Synovial Pathology.

Knee synovitis is a common, but nonspecific finding on MR imaging in patients with knee pain, with causes ranging from post-traumatic and osteoarthritis to inflammatory and infectious causes. Synovial thickening, joint effusion, and synovial enhancement are present across the spectrum of etiologies and do not allow differentiation between them in most instances. This article reviews synovial physiology and MR imaging of the normal synovium and synovitis, with discussion of specific pathologies and limited signs that suggest one diagnosis over another.

Deferoxamine as a potential cause of incidentally found T1-hyperintense urine on magnetic resonance imaging.

T1-hyperintense urine can be an incidental finding on MRI with many potential causes, such as prior gadolinium administration or hematuria. This is the case of a 33-year-old female with a history of sickle cell disease complicated by iron overload secondary to chronic transfusions, who has been on multiple different iron chelation regimens. Due to persistent iron overload despite various treatments, the patient was started on a new iron chelation regimen that utilized a protocol involving inpatient admission for high dose IV deferoxamine.

Treatments for Kienböck disease: what the radiologist needs to know.

The etiology of Kienböck disease, or avascular necrosis of the lunate, is controversial, and there are a myriad of treatments aimed at correcting the various hypothesized pathologies. Interventions to reduce mechanical stress on the lunate have been used for decades, including radial osteotomy with or without radial shortening, ulnar lengthening and metaphyseal core decompression procedures. However, these procedures require preservation of lunate architecture.

Pre-embolization evaluation of high-flow priapism: magnetic resonance angiography of the penis.

Purpose: High-flow priapism is often a sequela of perineal trauma resulting in an arteriocavernosal fistula (ACF) between a cavernosal artery and lacunar spaces of the penis. We report our experience utilizing magnetic resonance angiography (MRA) in addition to color Doppler Sonography (CDS) in the workup and treatment planning of 4 patients with high-flow priapism.

Methods: All patients had suspected high-flow priapism diagnosed by clinical exam and CDS and underwent MRA of the penis prior to sub-selective arterial embolization (SSAE) of the feeding vessel(s).

Regional and voxel-wise comparisons of blood flow measurements between dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) and arterial spin labeling (ASL) in brain tumors.

The objective of the current study was to evaluate the regional and voxel-wise correlation between dynamic susceptibility contrast (DSC) and arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) measurement of cerebral blood flow (CBF) in patients with brain tumors. Thirty patients with histologically verified brain tumors were evaluated in the current study. DSC-MRI was performed by first using a preload dose of gadolinium contrast, then collecting a dynamic image acquisition during a bolus of contrast, followed by posthoc contrast agent leakage correction.

Functional characterization of PmHS1, a Pasteurella multocida heparosan synthase.

Heparosan synthase 1 (PmHS1) from Pasteurella multocida Type D is a dual action glycosyltransferase enzyme that transfers monosaccharide units from uridine diphospho (UDP) sugar precursors to form the polysaccharide heparosan (N-acetylheparosan), which is composed of alternating (-alpha4-GlcNAc-beta1,4-GlcUA-1-) repeats. We have used molecular genetic means to remove regions nonessential for catalytic activity from the amino- and the carboxyl-terminal regions as well as characterized the functional regions involved in GlcUA-transferase activity and in GlcNAc-transferase activity. Mutation of either one of the two regions containing aspartate-X-aspartate (DXD) residue-containing motifs resulted in complete or substantial loss of heparosan polymerizing activity.

Identification of a distinct, cryptic heparosan synthase from Pasteurella multocida types A, D, and F.

The extracellular polysaccharide capsules of Pasteurella multocida types A, D, and F are composed of hyaluronan, N-acetylheparosan (heparosan or unsulfated, unepimerized heparin), and unsulfated chondroitin, respectively. Previously, a type D heparosan synthase, a glycosyltransferase that forms the repeating disaccharide heparosan backbone, was identified. Here, a approximately 73% identical gene product that is encoded outside of the capsule biosynthesis locus was also shown to be a functional heparosan synthase.

Identification and molecular cloning of a heparosan synthase from Pasteurella multocida type D.

Pasteurella multocida Type D, a causative agent of atrophic rhinitis in swine and pasteurellosis in other domestic animals, produces an extracellular polysaccharide capsule that is a putative virulence factor. It was reported previously that the capsule was removed by treating microbes with heparin lyase III. We molecularly cloned a 617-residue enzyme, pmHS, which is a heparosan (nonsulfated, unepimerized heparin) synthase.