Kara Gaetke-Udager

Multimodality imaging of splenic lesions and the role of non-vascular, image-guided intervention.

Splenic lesions are often incidentally detected on abdominal-computed tomography (CT), ultrasound, or magnetic resonance imaging (MRI), and these can pose a diagnostic challenge in patients with suspected or known malignancy. This review will discuss the multimodality imaging features of various benign and malignant splenic pathologies including trauma, infection, infarct, granulomatous disease, benign neoplasms such as hemangioma, hamartoma, and littoral cell angioma, cystic entities such as peliosis, splenic cysts, and pseudocysts, and malignant processes such as metastasis, lymphoma, angiosarcoma, and leiomyosarcoma. While several of these splenic pathologies have characteristic imaging features that are helpful in diagnosis, others have nonspecific findings. In such clinical dilemmas, image-guided intervention may be essential, and we therefore discuss the role of non-vascular, image-guided splenic interventions for diagnostic and therapeutic purposes. The radiologist can play a key part in the clinical diagnosis and management of splenic lesions, and therefore a thorough knowledge of the imaging features of splenic lesions and a thoughtful approach to their management is crucial.

Diagnostic Accuracy of Ultrasound, Contrast-enhanced CT, and Conventional MRI for Differentiating Leiomyoma From Leiomyosarcoma

RATIONALE AND OBJECTIVES This study aimed to determine whether uterine leiomyoma can be distinguished from uterine leiomyosarcoma on ultrasound (US), computed tomography (CT), and/or magnetic resonance imaging (MRI) without diffusion-weighted imaging. MATERIALS AND METHODS Institutional review board approval was obtained and informed consent was waived for this Health Insurance Portability and Accountability Act-compliant retrospective case-control diagnostic accuracy study. All subjects with resected uterine leiomyosarcoma diagnosed over a 17-year period (1998-2014) at a single institution for whom pre-resection US (n = 10), CT (n = 11), or MRI (n = 7) was available were matched by tumor size and imaging modality with 28 subjects with resected uterine leiomyoma. Six blinded radiologists (three attendings, three residents) assigned 5-point Likert scores for the following features: (1) margins, (2) necrosis, (3) hemorrhage, (4) vascularity, (5) calcifications, (6) heterogeneity, and (7) likelihood of malignancy (primary end point). Mean suspicion scores were calculated and receiver operating characteristic curves were generated. The ability of individual morphologic features to predict malignancy was assessed with logistic regression. RESULTS Mean suspicion scores were 2.5 ± 1.2 (attendings) and 2.4 ± 1.3 (residents) for leiomyoma, and 2.7 ± 1.3 (attendings) and 2.7 ± 1.4 (residents) for leiomyosarcoma. The areas under the receiver operating characteristic curves (range: 0.330-0.685) were not significantly different from chance, either overall (P = .36-.88) or by any modality (P = .28-.96), for any reader. Reader experience had no effect on diagnostic accuracy. No morphologic parameter was significantly predictive of malignancy (P = .10-.97). CONCLUSIONS Uterine leiomyoma cannot be differentiated accurately from leiomyosarcoma on US, CT, or MRI without diffusion-weighted imaging.

Myxoinflammatory fibroblastic sarcoma: spectrum of disease and imaging presentation

ObjectivesTo describe the imaging findings of a series of myxoinflammatory fibroblastic sarcomas (MFSs) from our institution, including a case of dedifferentiated MFS and two cases with areas of high-grade tumor, in addition to typical cases of low-grade tumor. To correlate the imaging findings with the pathologic features of these tumors.Subjects and methodsIRB approval was obtained. Retrospective search of the pathology database at our institution from 2000 to 2015 identified seven cases of MFS with available imaging. Imaging, pathology, and clinical data were reviewed.ResultsUnlike the majority of well-differentiated tumors in our series (four cases), one tumor showed dedifferentiation and two cases had areas of high-grade tumor. The dedifferentiated tumor showed peripheral post-contrast enhancement. One case with a substantial high-grade component showed osseous destruction and peripheral enhancement in the high-grade area, while the low-grade component enhanced diffusely. The second case had a small high-grade area and showed diffuse enhancement. All three of these cases had non-acral locations and lacked association with a tendon. The four cases of low-grade MFS demonstrated diffuse enhancement, were located in the distal extremities, and were associated with a tendon.ConclusionThe imaging findings of dedifferentiated and high-grade MFS differ from the more typical low-grade tumors in that they have nonenhancing areas, a non-acral location, lack association with a tendon, and may involve bone. The radiologist should be aware that MFS represents a spectrum that includes low-grade tumors, tumors with high-grade areas, and tumors with dedifferentiation and that this spectrum presents with differing imaging features.

A guide to imaging in bariatric surgery

There has been an increase in utilization of bariatric surgery and, as with any surgical procedure, the associated risk of complications. Many of the post bariatric surgical complications can be acute, necessitating an emergency room visit and imaging evaluation. Radiologists, especially in the emergency setting, need to be familiar with normal post-operative appearances and potential surgical complications. This review focuses on various bariatric surgical procedures that are performed, and illustrates normal and abnormal radiographic appearances seen on post-operative fluoroscopic upper GI studies and abdominal pelvis CT examinations.

Medical Education Research for Radiologists: A Road Map for Developing a Project

OBJECTIVE Medical education research is challenging to do well, but researchers can develop a robust project with knowledge of basic principles. Thoughtful creation of a study question, development of a conceptual framework, and attention to study design are crucial to developing a successful project. CONCLUSION A thorough understanding of research methods and elements of survey design is necessary. Projects that result in changes to behavior, clinical practice, and patient outcomes have the most potential for success.

MR imaging of the pelvis: a guide to incidental musculoskeletal findings for abdominal radiologists

Occasionally patients who undergo magnetic resonance imaging for presumed pelvic disease demonstrate unexpected musculoskeletal imaging findings in the imaged field. Such incidental findings can be challenging to the abdominal radiologist, who may not be familiar with their appearance or know the appropriate diagnostic considerations. Findings can include both normal and abnormal bone marrow, osseous abnormalities such as Paget’s disease, avascular necrosis, osteomyelitis, stress and insufficiency fractures, and athletic pubalgia, benign neoplasms such as enchondroma and bone island, malignant processes such as metastasis and chondrosarcoma, soft tissue processes such as abscess, nerve-related tumors, and chordoma, joint- and bursal-related processes such as sacroiliitis, iliopsoas bursitis, greater trochanteric pain syndrome, and labral tears, and iatrogenic processes such as bone graft or bone biopsy. Though not all-encompassing, this essay will help abdominal radiologists to identify and describe this variety of pelvic musculoskeletal conditions, understand key radiologic findings, and synthesize a differential diagnosis when appropriate.

Ultrasound evaluation of bursae: anatomy and pathological appearances

A bursa is an extra-articular sac that may communicate with a joint and functions to decrease friction between tendons and either bone or skin. Bursae can be classified as native and non-native (adventitious) bursae. The native bursae are lined with a synovial membrane and occur at predictable anatomical sites; knowledge of these normal structures can help distinguish them from other pathological entities. An adventitious bursa can form at sites of friction rather than at predictable anatomical sites, but otherwise have imaging features similar to native bursae. Bursal distention can occur from many pathological processes, most commonly resulting from chronic overuse injury. When imaging bursal pathological conditions, there is often an overlap of imaging findings, regardless of the cause. In general, ultrasound of a distended bursa reveals a fluid collection with either simple anechoic or more complex hypoechoic fluid. Bursal distention is characteristically unilocular and compressible, unlike other structures such as ganglion cysts, which are usually multilocular and non-compressible. This article reviews the anatomical locations of common bursae and shows pathological examples using ultrasound. Knowledge of typical locations and imaging appearances of bursae can aid in narrowing the differential diagnosis and guiding further management and treatment decisions.

Creating Three-dimensional Printed Models of Acetabular Fractures for Use as Educational Tools

Acetabular fractures are frequently encountered in some clinical practices, and the precise classification of these fractures greatly influences treatments and outcomes. The authors identified the need for an educational aid when teaching acetabular fracture classifications, given the complex spatial anatomy and the nonintuitive classification system that is commonly used. Three-dimensional ( 3D three-dimensional ) printing is an evolving technique that has applications as an educational aid, providing the student with a tangible object to interact with and learn from. In this article, the authors review their experience creating 3D three-dimensional printed models of the hip for educational purposes. Their goal was to create 3D three-dimensional printed models for use as educational aids when teaching acetabular fracture classifications. Complex cases involving a combination of fracture types, subtle nondisplaced fractures, and/or fractures with associated osteopenia or artifacts were excluded. The selected computed tomographic (CT) scans were loaded into a medical 3D three-dimensional volume-rendering program, and a 3D three-dimensional volumetric model was created. Standard Tessellation Language ( STL Standard Tessellation Language ) files were then exported to STL Standard Tessellation Language model-editing software and edited to retain only the involved hemipelvis. In some cases, the proximal femur and ipsilateral hemisacrum may be included to emphasize hip alignment or disruption of the force transfer. Displaced fracture fragments can be printed as separate segments or a single unit after the addition of struts. Printing was performed by using an additive manufacturing principle, with approximately 36-48 hours needed for printing, postprocessing, and drying. The cost to print a 1:1 scale model was approximately

Knee MRI: Vascular Pathology

100-

Benefits of a resident-run orientation for new radiology trainees

200, depending on the amount of plastic material used. These models can then be painted according to the two-column theory regarding acetabular fractures. ©RSNA, 2017.