Susan K. Hobbs

Magnetic resonance image–guided proteomics of human glioblastoma multiforme

To investigate the correlation between gadolinium contrast‐enhancement patterns on T1‐weighted magnetic resonance (MR) images and spatial changes in protein expression profiles in human glioblastoma multiforme (GBM) and the use of imaging as a noninvasive technique to evaluate the heterogeneity of solid tumors prior to microarray analysis.

Dalteparin thromboprophylaxis in cancer patients at high risk for venous thromboembolism: A randomized trial

BACKGROUND Ambulatory cancer patients at high-risk for venous thromboembolism (VTE) can be identified using a validated risk score (Khorana score). We evaluated the benefit of outpatient thromboprophylaxis with dalteparin in high-risk patients in a multicenter randomized study. METHODS Cancer patients with Khorana score≥3 starting a new systemic regimen were screened for VTE and if negative randomized to dalteparin 5000units daily or observation for 12weeks. Subjects were screened with lower extremity ultrasounds every 4weeks on study and with chest CT at 12weeks. The primary efficacy endpoint was all VTE over 12weeks and primary safety endpoint was clinically relevant bleeding events over 13weeks. The study was terminated early due to low accrual. RESULTS Of 117 enrolled patients, 10 (8.5%) had VTE on baseline screening and were not randomized. Of 98 randomized patients, VTE occurred in 12% (N=6/50) of patients on dalteparin and 21% (N=10/48) on observation (hazard ratio, HR 0.69, 95% CI 0.23-1.89). Major bleeding was similar (N=1) in each arm but clinically relevant bleeding was higher in dalteparin arm (N=7 versus 1 on observation) (HR=7.0, 95% CI 1.2-131.6). There was no difference in overall survival. CONCLUSIONS Thromboprophylaxis is associated with a non-significantly reduced risk of VTE and significantly increased risk of clinically relevant bleeding in this underpowered study. The Khorana score successfully identifies patients with high incidence of VTE both at baseline and during treatment. Future studies should continue to focus on risk-adapted approaches to reduce the burden of VTE in cancer. TRIAL REGISTRATION clinicaltrials.gov identifier: NCT00876915.

RADPEER Peer Review: Relevance, Use, Concerns, Challenges, and Direction Forward

RADPEER is a product developed by the ACR that aims to assist radiologists with quality assessment and improvement through peer review. The program opened in 2002, was initially offered to physician groups in 2003, developed an electronic version in 2005 (eRADPEER), revised the scoring system in 2009, and first surveyed the RADPEER membership in 2010. In 2012, a survey was sent to 16,000 ACR member radiologists, both users and nonusers of RADPEER, with the goal of understanding how to make RADPEER more relevant to its members. A total of 31 questions were used, some of which were repeated from the 2010 survey. The ACRs RADPEER committee has published 3 papers on the program since its inception. In this report, the authors summarize the survey results and suggest future opportunities for making RADPEER more useful to its membership.

Cardiac Imaging: Part 1, MR Pulse Sequences, Imaging Planes, and Basic Anatomy

OBJECTIVE MRI is a well-established modality for evaluating congenital and acquired cardiac diseases. This article reviews the latest pulse sequences used for cardiac MRI. In addition, the standard cardiac imaging planes and corresponding anatomy are described and illustrated. CONCLUSION Familiarity with the basic pulse sequences, imaging planes, and anatomy pertaining to cardiac MRI is essential to formulate optimal protocols and interpretations.

Looking beyond the thrombus: essentials of pulmonary artery imaging on CT.

AbstractBackgroundPulmonary arteries are not just affected by thrombus. Congenital and acquired conditions can also involve the pulmonary arteries. An awareness of these conditions is important for the radiologist interpreting chest computed tomography (CT).MethodsThe anatomy of the pulmonary arteries was reviewed. CT and magnetic resonance (MR) acquisition protocols for imaging the pulmonary arteries were discussed. The imaging appearances of congenital and acquired anomalies involving the pulmonary arteries, using CT and other modalities, were presented.ResultsImaging features of congenital anomalies presented include pulmonary agenesis, partial pulmonary artery agenesis, patent ductus arteriosus, pulmonary artery sling, congenital pulmonary artery stenosis and coronary to pulmonary artery fistula. Acquired pulmonary artery anomalies discussed include arteritis, infected aneurysm and sarcoma. Pulmonary artery filling defects besides thromboembolism are also discussed, including foreign body emboli. Imaging features of bronchogenic carcinoma and mediastinal fibrosis demonstrating compression of the pulmonary arteries are presented, followed by a brief discussion of post repair appearance of the pulmonary arteries for congenital heart disease.ConclusionsCongenital and acquired pulmonary artery anomalies have a characteristic appearance on a variety of imaging modalities. An acquaintance with the imaging features of these anomalies is needed to avoid misinterpretation and reach the correct diagnosis. Teaching Points • Discuss a variety of congenital and acquired anomalies of the pulmonary arteries.• Discuss the imaging appearance of the presented congenital or acquired pulmonary artery anomalies.• Describe CT and MR acquisition protocols for imaging the pulmonary arteries.• Review the anatomy of the pulmonary arteries.

MRI evaluation prior to Transcatheter Aortic Valve Implantation (TAVI): When to acquire and how to interpret

AbstractTranscatheter Aortic Valve Implantation (TAVI) is increasingly being used in patients with severe aortic stenosis who are not candidates for surgery. ECG-gated CT angiography (CTA) plays an important role in the preoperative planning for these devices. As the number of patients undergoing these procedures increases, a subset of patients is being recognized who have contraindications to iodinated contrast medium, either due to a prior severe allergic type reaction or poor renal function. Another subgroup of patients with low flow and low gradient aortic stenosis is being recognized that are usually assessed for severity of aortic stenosis by stress echocardiography. There are contraindications to stress echocardiography and some of these patients may not be able to undergo this test. Non-contrast MRI can be a useful emerging modality for evaluating these patients. In this article, we discuss the emerging indications of non-contrast MRI in preoperative assessment for TAVI and describe the commonly used MRI sequences. A comparison of the most important measurements obtained for TAVI assessment on CTA and MRI from same subjects is included. Teaching Points • MRI can be used for preoperative assessment of aortic annulus. • MRI is an alternate to CTA when iodinated contrast is contraindicated. • Measurements obtained by non-contrast MRI are similar to contrast enhanced CTA. • MRI can be used to assess severity of aortic stenosis.

Imaging Features of Chest Wall Tumors

The differential diagnosis of chest wall tumors is diverse, including both benign and malignant lesions, and local extension of adjacent disease. Chest wall tumors can arise from the soft tissue and osseous structures of the thorax, which include the ribs, cartilage, nerves, muscles, fat, and lymph nodes. As most chest wall tumors are amenable to biopsy, the initial role of chest radiography is to localize a lesion to the chest wall and to reduce the need for biopsy of benign tumors. Advanced imaging, including CT or MRI, can be used to further evaluate tumor margins, soft tissue involvement, and degree of bony or spinal cord invasion. Techniques to localize and characterize chest wall tumors and a detailed differential diagnosis will be discussed.

Beyond bronchitis: a review of the congenital and acquired abnormalities of the bronchus

AbstractAnomalies of the bronchus can be both congenital and acquired. Several different congenital aberrations of the bronchial anatomy are commonly encountered including tracheal bronchus, accessory cardiac bronchus, and bronchial agenesis/aplasia/hypoplasia. In addition, Williams-Campbell syndrome and cystic fibrosis are two other congenital conditions that result in bronchial pathology. Acquired pathology affecting the bronchi can typically be divided into three broad categories of bronchial disease: bronchial wall thickening, dilatation/bronchiectasis, and obstruction/stenosis. Bronchial wall thickening is the common final response of the airways to irritants, which cause the bronchi to become swollen and inflamed. Bronchiectasis/bronchial dilatation can develop in response to many aetiologies, including acquired conditions such as infection, pulmonary fibrosis, recurrent or chronic aspiration, as well as because of congenital conditions such as cystic fibrosis. The causes of obstruction and stenosis are varied and include foreign body aspiration, acute aspiration, tracheobronchomalacia, excessive dynamic airway collapse, neoplasm, granulomatous disease, broncholithiasis, and asthma. Knowledge of normal bronchial anatomy and its congenital variants is essential for any practicing radiologist. It is the role of the radiologist to identify common imaging patterns associated with the various categories of bronchial disease and provide the ordering clinician a useful differential diagnosis tailored to the patient’s clinical history and imaging findings. Teaching Points • Bronchial disorders are both congenital and acquired in aetiology.• Bronchial disease can be divided by imaging appearance: wall thickening, dilatation, or obstruction.• Bronchial wall thickening is the common final response of the airways to irritants.• Imaging patterns must be recognised and the differential diagnosis tailored for patient management.

Spontaneous Esophageal Hematoma in a Patient With Atrial Fibrillation

We report a case of a spontaneous esophageal hematoma in an anticoagulated patient with atrial fibrillation previously complicated by a cerebrovascular accident. A multidisciplinary discussion resulted in holding of anticoagulation until the esophageal hematoma resolved. The patient was managed nonoperatively and discharged, but returned with a new neurologic deficit 3 weeks later. Aspirin treatment was resumed. After complete resolution of hematoma on outpatient scans, warfarin treatment was restarted. The challenges of managing an esophageal hematoma in a patient requiring anticoagulation are discussed.

Traumatic Rib Injury: Patterns, Imaging Pitfalls, Complications, and Treatment

The ribs are frequently affected by blunt or penetrating injury to the thorax. In the emergency department setting, it is vital for the interpreting radiologist to not only identify the presence of rib injuries but also alert the clinician about organ-specific injury, specific traumatic patterns, and acute rib trauma complications that require emergent attention. Rib injuries can be separated into specific morphologic fracture patterns that include stress, buckle, nondisplaced, displaced, segmental, and pathologic fractures. Specific attention is also required for flail chest and for fractures due to pediatric nonaccidental trauma. Rib fractures are associated with significant morbidity and mortality, both of which increase as the number of fractured ribs increases. Key complications associated with rib fracture include pain, hemothorax, pneumothorax, extrapleural hematoma, pulmonary contusion, pulmonary laceration, acute vascular injury, and abdominal solid-organ injury. Congenital anomalies, including supernumerary or accessory ribs, vestigial anterior ribs, bifid ribs, and synostoses, are common and should not be confused with traumatic pathologic conditions. Nontraumatic mimics of traumatic rib injury, with or without fracture, include metastatic disease, primary osseous neoplasms (osteosarcoma, chondrosarcoma, Ewing sarcoma, Langerhans cell histiocytosis, and osteochondroma), fibrous dysplasia, and Paget disease. Principles of management include supportive and procedural methods of alleviating pain, treating complications, and stabilizing posttraumatic deformity. By recognizing and accurately reporting the imaging findings, the radiologist will add value to the care of patients with thoracic trauma. Online supplemental material is available for this article. ©RSNA, 2017.