Imaging Spectrum of Duodenal Emergencies.

The duodenum, the first portion of the small bowel, is divided into four segments and extends to both retro- and intraperitoneal spaces. Some conditions arise primarily from the duodenum, but it can be secondarily affected by processes that involve neighboring structures. When duodenal emergencies are not identified and treated promptly, they may result in high morbidity and mortality. Imaging plays an important role in the diagnosis of duodenal conditions in the acute setting. However, the radiologic findings can be subtle, and awareness of relevant patient history and clinical presentation is important as it may increase the index of suspicion and one's ability to diagnose these conditions. Duodenal peptic disease is common and can be complicated by bleeding and perforation. The duodenum can be secondarily involved by pancreatitis and gallbladder pathologic conditions and may be affected by iatrogenic complications following endoscopic procedures. Traumatic injuries to the duodenum are generally uncommon, with penetrating traumatic injury being the most frequent mechanism of injury. Duodenal vascular pathologic conditions such as aortoduodenal fistula are uncommon but can be life threatening. The knowledge of which pathologic condition can involve which duodenal segment can help the radiologist establish a differential diagnosis and achieve a more targeted imaging approach. The online slide presentation from the RSNA Annual Meeting is available for this article. ©RSNA, 2020.

Multidetector CT of Laryngeal Injuries: Principles of Injury Recognition.

Blunt laryngeal trauma is associated with high morbidity and mortality. However, owing to their relatively rare occurrence, laryngeal injuries may be missed or underdiagnosed. Even subtle abnormalities at multidetector CT may correspond to significant functional abnormalities. It is important to understand normal CT laryngeal anatomy and develop a systematic review of the cervical soft tissues and laryngeal skeleton in patients who undergo screening CT cervical spine or other neck examinations in the setting of trauma, such as CT angiography. Multidetector CT findings of the normal larynx are reviewed, and blunt laryngeal injuries including soft-tissue edema, hematoma, mucosal lacerations, cartilage fracture, cricoarytenoid dislocation, and vocal fold paralysis are presented. The radiologist plays an important role in diagnosis and may be the first to identify laryngeal injuries that are not evident at physical examination. This article reviews normal laryngeal anatomy, presents various blunt laryngeal injuries at multidetector CT with case examples, discusses the role of multidetector CT in acute management, and describes pitfalls of diagnosis. ©RSNA, 2019.

Simplified diagnostic algorithm for Lauge-Hansen classification of ankle injuries.

Ankle injuries occur in a predictable sequence, allowing a logical understanding of their classification once the injury mechanism is recognized. The Lauge-Hansen classification system was developed on the basis of the mechanism of trauma and is useful for guiding treatment. Three radiographic views of the ankle (anteroposterior, mortise, and lateral) are necessary to classify an injury with the Lauge-Hansen system. Two additional criteria are also necessary: the position of the foot at the time of injury and the direction of the deforming force. Because understanding the mechanism of trauma is fundamental to classifying the injury, three-dimensional movies were assembled for each classification, showing the sequence of ligament rupture and bone fractures that occurs with each type of traumatic mechanism. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.322115017/-/DC1.

A new strategy for respiration compensation, applied toward 3D free-breathing cardiac MRI.

In thorax and abdomen imaging, image quality may be affected by breathing motion. Cardiac MR images are typically obtained while the patient holds his or her breath, to avoid respiration-related artifacts. Although useful, breath-holding imposes constraints on scan duration, which in turn limits the achievable resolution and SNR. Longer scan times would be required to improve image quality, and effective strategies are needed to compensate for respiratory motion. A novel approach at respiratory compensation, targeted toward 3D free-breathing cardiac MRI, is presented here. The method aims at suppressing the negative effects of respiratory-induced cardiac motion while capturing the heart's beating motion. The method is designed so that the acquired data can be reconstructed in two different ways: First, a time series of images is reconstructed to quantify and correct for respiratory motion. Then, the corrected data are reconstructed a final time into a cardiac-phase series of images to capture the heart's beating motion. The method was implemented, and initial results are presented. A cardiac-phase series of 3D images, covering the entire heart, was obtained for two free-breathing volunteers. The present method may prove especially useful in situations where breath-holding is not an option, for example, for very sick, mentally impaired or infant patients.

Primary synovial sarcoma of the chest: radiographic and clinicopathologic correlation.

Primary synovial sarcoma of the thorax is rare. Origin of thoracic synovial sarcoma in the pleura or lung was first described only 7 years ago. Radiologic characteristics of this disease have not yet been studied in a formal series. The authors sought to define the radiologic features of primary thoracic synovial sarcoma and to correlate the findings with clinical and pathologic features. They examined clinical, radiologic, and pathologic features of five patients with primary synovial sarcoma of the chest. Radiologic evaluation included conventional radiographs, computed tomographic scans, and magnetic resonance images of the chest. Patients included three men and two women who ranged in age from 28 to 40 years. Primary tumors involved the chest wall (n = 2), lung (n = 1), or both (n = 2). Chest pain was the most common presenting symptom. Although conventional radiographs often showed the lesions to be ill defined, computed tomographic scans showed well-defined masses in every case. Heterogeneous enhancement and an absence of calcification were also seen. Pathologic evaluation demonstrated synovial sarcoma with equal distribution between the monophasic and biphasic variants. The chromosomal translocation X;18 was demonstrated in four of four cases tested. All patients were treated by resection. Recurrence was demonstrated radiologically in four patients at 2 to 14 months. All patients were alive at 9 to 58 months of follow-up. The authors conclude that primary synovial sarcoma of the chest occurs in young adults, most commonly presenting with chest pain. It is characterized radiologically by a heterogeneously enhancing well-defined mass without calcifications.