Brady K. Huang

Diabetic Myopathy: MRI Patterns and Current Trends

OBJECTIVE This study retrospectively evaluates diabetic myopathy in a large referral hospital population. It describes the MRI findings and the distribution of muscle involvement, including comparison with clinical parameters. MATERIALS AND METHODS MRI reports of the lower extremities from July 1999 through January 2006 were reviewed and compared with clinical parameters for patients with diabetic myopathy. Clinical parameters (e.g., type of diabetes, hemoglobin A(1C) level, creatine kinase level, and erythrocyte sedimentation rate [ESR]) and the presence of complications, including nephropathy, neuropathy, and retinopathy, were noted. The distribution of muscle involvement and imaging features were reviewed. RESULTS Over a 79-month period, 21 extremities (11 thighs and 10 calves) of 16 patients were imaged. Fourteen (88%) patients had type 2 diabetes, and two (12%) had type 1 diabetes. Four patients (25%) had disease in more than one location. In the thigh, the anterior compartment was involved in all patients. The posterior compartment was affected in nine (90%) of 10 calves. Muscle infarction and necrosis was seen in eight (38%) extremities. The creatine kinase level, ESR, and hemoglobin A(1C) level were elevated in the majority of cases. Coexisting nephropathy (50%), neuropathy (50%), and retinopathy (38%) were present in these patients. CONCLUSION Diabetic myopathy may occur more frequently in patients with type 2 diabetes than previously reported. In this population, T2-weighted and contrast-enhanced images have similar findings, and the increased coexistence of nephropathy makes administration of gadolinium-based contrast agents ill-advised. With a typical clinical presentation and MRI findings, a confident diagnosis can be made, and potentially harmful biopsy is avoided. Diabetic myopathy encompasses a spectrum of diseases, including muscle inflammation, ischemia, hemorrhage, infarction, necrosis, fibrosis, and fatty atrophy. It is usually seen with long-standing, poorly controlled diabetes.

MRI of the Metatarsophalangeal Joints: Improved Assessment With Toe Traction and MR Arthrography

OBJECTIVE This study evaluates the impact of toe traction and direct MR arthrography on the assessment of articular cartilage and plantar plates of the first and second metatarsophalangeal joints. MRI of five cadaveric feet was obtained utilizing four techniques: before arthrography without and with traction and after arthrography without and with traction. CONCLUSION The combination of toe traction and MR arthrography is perceived to be superior in the articular cartilage and plantar plate evaluation.

Injury of the Gluteal Aponeurotic Fascia and Proximal Iliotibial Band: Anatomy, Pathologic Conditions, and MR Imaging

The fascia lata, or deep fascia of the thigh, is a complex anatomic structure that has not been emphasized as a potential source of pelvic and hip pain. This structure represents a broad continuum of fibrous tissue about the buttock, hip, and thigh that receives contributions from the posteriorly located aponeurotic fascia covering the gluteus medius muscle and from the more laterally located iliotibial band (ITB). At the pelvis and hip, the ITB consists of three layers that merge at the lower portion of the tensor fasciae latae muscle. The gluteal aponeurotic fascia and ITB merge at the buttock and hip before extending inferiorly to the Gerdy tubercle at the anterolateral tibia. Injuries to these anatomic structures are an underdiagnosed cause of pain and disability and may clinically mimic more common processes affecting the hip and proximal thigh. Categories of disease include overuse injuries, traumatic injuries, degenerative lesions, and inflammatory lesions. Familiarity with the anatomy and pathologic conditions of the fascia lata and its components is important in their recognition as a potential source of symptoms. This article illustrates the anatomy of this complex fascia through anatomic-pathologic correlation and describes the magnetic resonance imaging appearances of the pathologic conditions involving it.

Balancing Clinical Service and Education in the Radiology Residency

RATIONALE AND OBJECTIVES Among the various medical disciplines, the radiology residency faces unique challenges when balancing clinical service and education, which have not been explored in the literature. MATERIALS AND METHODS The authors present a summary of material generated during collaborative sessions at the 56th Annual Meeting of the Association of University Radiologists in Seattle, Washington, in March 2008, including strategies on maintaining an appropriate emphasis on education in the face of increasing service obligations, with a review of the pertinent literature. RESULTS Although the topic of service and education has been explored in the medical and surgical literature, little has been published in the radiology literature. The portability of radiology and the relative lack of patient contact can lead to the redistribution of residents as a matter of convenience to fill service gaps, often at the expense of the educational goals of training programs. Residents and faculty members alike must take part in both service and educational obligations without compromising patient care. Physician extenders, call schedule optimization, and other strategies and resources can help ensure that a proper balance is maintained. CONCLUSION The radiology residency presents unique challenges to the service and education balance. The authors highlight several strategies to address these challenges.

Cholecystitis of a duplicated gallbladder complicated by a cholecystoenteric fistula

Gallbladder duplications are uncommon anatomic variants that are sometimes mistaken for other entities on imaging. We present a surgically confirmed case of cholecystitis in a ductular-type duplicated gallbladder complicated by the formation of an inflammatory fistula to the adjacent duodenum. Both US and magnetic resonance cholangiopancreatography were performed preoperatively, in addition to intraoperative cholangiography, which confirmed the presence of a duplicated gallbladder.

Imaging of the rotator cuff.

The imaging evaluation of the rotator cuff augments the clinical evaluation. Radiography, computed tomography, and magnetic resonance imaging all have various roles in the assessment of the rotator cuff, which can be combined with arthrography for added detail. Furthermore, ultrasound is a very useful technique that provides functional information that is not offered by simple anatomic imaging.

Cartilage assessment of the metacarpophalangeal joints: cadaveric study with magnetic resonance arthrography and finger traction

We investigated the efficacy of axial traction of the fingers combined with magnetic resonance (MR) arthrography in assessing the metacarpophalangeal (MCP) joint cartilage in cadavers. Cartilage was imaged and graded before/after MR arthrography, with/without traction, then correlated with cadaveric sectioning. The application of traction with MR arthrography is a promising technique for improved visualization of the articular cartilage of the MCP joints compared with similar imaging without traction and/or without arthrography, but its true benefit requires further study.

Novel anatomic concepts in magnetic resonance imaging of the rotator cuff tendons and the footprint.

The anatomic and histologic descriptions of the rotator cuff tendons and footprints are continuously evolving, and new discoveries have led to novel concepts in our understanding of rotator cuff tendon pathology. These concepts may be translated into the analysis of these footprints with imaging methods, particularly magnetic resonance imaging.

Sonographic Appearance of a Retained Tunneled Catheter Cuff Causing a Foreign Body Reaction

onography is useful in imaging and diagnosing occult soft tissue foreign bodies, especially those that are radiolucent. The sonographic features of frequently encountered foreign bodies, including metal, glass, gravel, wood, and plastic, have been described in the literature. Foreign bodies from retained surgical instruments or medical devices are often easily identified on radiographs because they are usually radiopaque or contain radiopaque markers. Similarly, vascular catheters are radiopaque; however, the cuffs found with tunneled catheters are generally radiolucent. Tunneled vascular catheters with cuffs are commonly used in both hospital and outpatient settings. A long-term complication of these is cuff retention when removed by manual traction, although this is rarely of clinical importance. Despite the fact that cuff removal is advocated by catheter manufacturers, they are commonly left in place when retained. We present the sonographic findings with histopathologic correlation of a retained cuff causing a foreign body giant cell reaction 11 months after the catheter had been initially removed. In this case, a hypoechoic halo of granulation tissue was seen surrounding an echogenic shadowing catheter cuff.

Monitoring of the central blood pressure waveform via a conformal ultrasonic device

Continuous monitoring of the central blood pressure waveform from deeply embedded vessels such as the carotid artery and jugular vein has clinical value for the prediction of all-cause cardiovascular mortality. However, existing non-invasive approaches, including photoplethysmography and tonometry, only enable access to the superficial peripheral vasculature. Although current ultrasonic technologies allow non-invasive deep tissue observation, unstable coupling with the tissue surface resulting from the bulkiness and rigidity of conventional ultrasound probes introduces usability constraints. Here, we describe the design and operation of an ultrasonic device that is conformal to the skin and capable of capturing blood pressure waveforms at deeply embedded arterial and venous sites. The wearable device is ultrathin (240 μm) and stretchable (with strains up to 60%), and enables the non-invasive, continuous and accurate monitoring of cardiovascular events from multiple body locations, which should facilitate its use in a variety of clinical environments.An ultrasonic and stretchable device conformal to the skin that captures blood pressure waveforms at deeply embedded arterial and venous sites enables the continuous monitoring of cardiovascular events.