Constantine A. Raptis

Erdheim-Chester disease with interatrial septum involvement.

Erdheim-Chester disease is an uncommon non-Langerhans cell histiocytosis with systemic manifestations. Most cases discuss radiologic findings once a pathologic diagnosis has already been established. We describe a patient with symptoms and no previously known diagnosis who was imaged with computed tomography, magnetic resonance imaging, and positron emission tomography. This case is unusual in that radiologic imaging demonstrated interatrial septum and diffuse cardiac involvement, in addition to the other characteristic lesions of Erdheim-Chester disease. The importance of this case to the radiologist is the expansion of the differential diagnosis of processes involving the interatrial septum and retroperitoneum.

Adenomyotic cyst of the uterus in an adolescent.

Cystic adenomyosis is a rare form of adenomyosis of the uterine myometrium that has been described in older adults. This condition has not previously been reported in the pediatric radiology literature. In this case report, we describe an adenomyotic cyst in an adolescent girl that was imaged with US, CT, and MR and proved by surgical pathology. Understanding of the radiologic features of cystic adenomyosis is important for noninvasive diagnosis and effective medical/surgical management.

Comparison of apparent diffusion coefficient maps to T2-weighted images for target delineation in cervix cancer brachytherapy

Purpose T2-weighted (T2W) magnetic resonance imaging (MRI) has been used for target delineation in cervix cancer brachytherapy. The objective of this study was to examine the feasibility of using diffusion-weighted magnetic resonance imaging (DWI) for target delineation as compared against T2W imaging. Material and methods Fifteen cervix cancer patients, implanted with tandem and ovoid applicators, underwent T2W turbo-spin echo imaging and DWI with a maximum diffusion factor of 800 sec/mm2 on a 1.5-T MR scanner. Apparent diffusion coefficient (ADC) maps were derived from the DWI. The gross tumor volume was manually delineated on the T2W and ADC datasets for each patient. The agreement between T2W- and ADC-delineated volumes was assessed using the Dice similarity coefficient (DSC). An algorithm was developed to compare the edge contrast of the delineated volumes on T2W images and ADC maps by calculating the percentage difference in the intensity values of selected regions of pixels inside versus outside the target contour. Results ADC-delineated volumes were generally smaller than T2W-delineated volumes, yielding a low DSC of 0.54 ± 0.22. ADC maps were found to display superior definition of the target volume edge relative to T2W images, yielding a statistically significant difference between the mean edge contrast on ADC (12.7 ± 7.7%) versus that on T2W images (4.6 ± 3.2%; p = 0.0010). Conclusions These results suggest that incorporating the use of DWI for cervix cancer brachytherapy may yield gross tumor volumes that are different from those based on T2W images alone.

Imaging of left ventricular device complications.

Left ventricular assist devices have become an increasingly common life-extending therapy for patients with end-stage heart failure. These devices may be used as a bridge to transplant, destination therapy, or to recovery, providing either pulsatile or nonpulsatile support. Because of the increasing frequency of left ventricular assist device utilization and the improved short-term and long-term survival after placement, there has been a parallel increase in the radiologic imaging of patients with these devices, mandating radiologists’ awareness of the manifestations of common complications, including infection, thrombosis and embolism, cannula obstruction, hemorrhage, and complications of adjacent vessels and viscera, all of which will be discussed in this pictorial essay.

Imaging in blunt cardiac injury: Computed tomographic findings in cardiac contusion and associated injuries

BACKGROUND Blunt cardiac injury (BCI) may manifest as cardiac contusion or, more rarely, as pericardial or myocardial rupture. Computed tomography (CT) is performed in the vast majority of blunt trauma patients, but the imaging features of cardiac contusion are not well described. PURPOSE To evaluate CT findings and associated injuries in patients with clinically diagnosed BCI. MATERIALS AND METHODS We identified 42 patients with blunt cardiac injury from our institutions electronic medical record. Clinical parameters, echocardiography results, and laboratory tests were recorded. Two blinded reviewers analyzed chest CTs performed in these patients for myocardial hypoenhancement and associated injuries. RESULTS CT findings of severe thoracic trauma are commonly present in patients with severe BCI; 82% of patients with ECG, cardiac enzyme, and echocardiographic evidence of BCI had abnormalities of the heart or pericardium on CT; 73% had anterior rib fractures, and 64% had pulmonary contusions. Sternal fractures were only seen in 36% of such patients. However, myocardial hypoenhancement on CT is poorly sensitive for those patients with cardiac contusion: 0% of right ventricular contusions and 22% of left ventricular contusions seen on echocardiography were identified on CT. CONCLUSION CT signs of severe thoracic trauma are frequently present in patients with severe BCI and should be regarded as indirect evidence of potential BCI. Direct CT findings of myocardial contusion, i.e. myocardial hypoenhancement, are poorly sensitive and should not be used as a screening tool. However, some left ventricular contusions can be seen on CT, and these patients could undergo echocardiography or cardiac MRI to evaluate for wall motion abnormalities.

CT of Gastric Emergencies.

Abdominal pain, nausea, and vomiting are common presenting symptoms among adult patients seeking care in the emergency department, and, with the increased use of computed tomography (CT) to image patients with these complaints, radiologists will more frequently encounter a variety of emergent gastric pathologic conditions on CT studies. Familiarity with the CT appearance of emergent gastric conditions is important, as the clinical presentation is often nonspecific and the radiologist may be the first to recognize gastric disease as the cause of a patients symptoms. Although endoscopy and barium fluoroscopy remain important tools for evaluating patients with suspected gastric disease in the outpatient setting, compared with CT these modalities enable less comprehensive evaluation of patients with nonspecific complaints and are less readily available in the acute setting. Endoscopy is also more invasive than CT and has greater potential risks. Although the mucosal detail of CT is relatively poor compared with barium fluoroscopy or endoscopy, CT can be used with the appropriate imaging protocols to identify inflammatory conditions of the stomach ranging from gastritis to peptic ulcer disease. In addition, CT can readily demonstrate the various complications of gastric disease, including perforation, obstruction, and hemorrhage, which may direct further clinical, endoscopic, or surgical management. We will review the normal anatomy of the stomach and discuss emergent gastric disease with a focus on the usual clinical presentation, typical imaging appearance, and differentiating features, as well as potential imaging pitfalls.

The 7th Edition of the TNM Staging System for Lung Cancer: What the Radiologist Needs to Know

Today lung cancer remains the leading cause of cancer-related death in the United States, accounting for 28% of all cases. Radiologists play an important role in the assessment of this large number of patients. Given the important role imaging plays in the care of patients with lung cancer, it is incumbent on the radiologist to have a firm understanding of the TNM (tumor-node-metastasis) staging system used to describe the distribution of disease in lung cancer. This article reviews the 7th Edition of the TNM staging system for lung cancer and important changes from the 6th Edition.

On-Call Radiology Resident Discrepancies: Categorization by Patient Location and Severity

PURPOSE To report discrepancy rates for examinations interpreted by on-call residents overall and by resident training level, and to describe a novel discrepancy classification system based on patient location and severity that facilitates recording of discrepancy data, helps ensure proper communication of report changes, and allows our radiology department to assume responsibility for contacting discharged patients with non-time-dependent results. METHODS A HIPAA-compliant, institutional review board-exempt review of two years (January 2013 to December 2014) of discrepancy data was retrospectively performed for total number of examination interpreted, discrepancy rates, resident training level, and discrepancy categories. Most common diagnoses and means of results communication for discharged patients were also recorded. RESULTS Radiology residents interpreted 153,420 examinations after hours and had 2169 discrepancies, for an overall discrepancy rate of 1.4%. Discrepancy rates for postgraduate year (PGY)-3, PGY-4, and PGY-5 residents were 1.31%, 1.65%, and 1.88%, respectively. The rate of critical discrepancies was extremely low (10/153,420 or 0.007%). A total of 502 patients (23.2% of all discrepancies) were discharged at the time their discrepancy was identified, 60% of whom had non-time-dependent discrepancies that were communicated by radiologists; 32.4% of these had addended results telephoned to a PCP, 43.4% had addended results telephoned to the patient, and the remaining 24.2% required a registered letter. Eight percent of patients with non-time-dependent findings were lost to follow-up. CONCLUSIONS Our resident discrepancy rates were comparable to those published previously, with extremely low rates of critical discrepancies. Radiologists assumed responsibility for contacting the majority of discharged patients with discrepant results, a minority of whom were lost to follow-up.

Beyond whole-body imaging: advanced imaging techniques of PET/MRI.

Abstract PET/MRI is a hybrid imaging modality that is gaining clinical interest with the first Food and Drug Administration–approved simultaneous imaging system recently added to the clinical armamentarium. Several advanced PET/MRI applications, such as high-resolution anatomic imaging, diffusion-weighted imaging, motion correction, and cardiac imaging, show great potential for clinical use. The purpose of this article is to highlight several advanced PET/MRI applications through case examples and review of the current literature.

Imaging of the Patient with Thoracic Outlet Syndrome

Patients with symptoms from compression of the neurovascular bundle in the thoracic outlet are described as having thoracic outlet syndrome (TOS), which is best thought of as three conditions classified according to which structures are involved. The purpose of this article is to review the role of imaging in evaluation of patients with TOS, beginning with diagnosis and extending through postoperative management. While diagnosis of TOS still rests on the patients presenting history and physical examination, imaging examinations are helpful in supporting the diagnosis, delineating abnormal anatomy, determining which structures are compressed, identifying the site of compression, and excluding other diagnoses. Magnetic resonance imaging is the noninvasive imaging modality of choice in evaluating patients with suspected TOS, but computed tomography also plays an important role, particularly in delineating bone anatomy. Evidence of vascular damage is required to make the diagnosis of TOS at imaging. Dynamic compression of the axillosubclavian vessels at the thoracic outlet can be a finding supportive of the diagnosis of TOS but is not a stand-alone diagnostic criterion, as it can be seen in patients without TOS. As diagnosis and treatment of TOS increase, radiologists will increasingly encounter the TOS patient after decompression surgery. Recognition of the expected postoperative appearance of these patients is critical, as is an understanding of the imaging findings of potential short- and long-term complications. (©)RSNA, 2016.