Body Imaging of Bacterial and Parasitic Zoonoses: Keys to Diagnosis.

Zoonotic infections, which are transmitted from animals to humans, have been a substantial source of human disease since antiquity. As the human population continues to grow and human influence on the planet expands, humans frequently encounter both domestic and wild animals. This has only increased as deforestation, urbanization, agriculture, habitat fragmentation, outdoor recreation, and international travel evolve in modern society, all of which have resulted in the emergence and reemergence of zoonotic infections. Zoonotic infections pose a diagnostic challenge because of their nonspecific clinical manifestations and the need for specialized testing procedures to confirm these diagnoses. Affected patients often undergo imaging during their evaluation, and a radiologist familiar with the specific and often subtle imaging patterns of these infections can add important clinical value. The authors review the multimodality thoracic, abdominal, and musculoskeletal imaging findings of zoonotic bacterial (eg, Bartonella henselae, Pasteurella multocida, Francisella tularensis, Coxiella burnetii, and Brucella species), spirochetal (eg, Leptospira species), and parasitic (eg, Echinococcus, Paragonimus, Toxocara, and Dirofilaria species) infections that are among the more commonly encountered zoonoses in the United States. Relevant clinical, epidemiologic, and pathophysiologic clues such as exposure history, occupational risk factors, and organism life cycles are also reviewed. Although many of the imaging findings of zoonotic infections overlap with those of nonzoonotic infections, granulomatous diseases, and malignancies, radiologists' familiarity with the imaging patterns can aid in the differential diagnosis in a patient with a suspected or unsuspected zoonotic infection. © RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Transcatheter Aortic Valve Replacement: Alternative Access beyond the Femoral Arterial Approach.

Aortic stenosis is the most prevalent valvular cardiovascular disease affecting the population over the age of 65 years. Transcatheter aortic valve replacement (TAVR) was developed as a minimally invasive surgical intervention to treat aortic stenosis in patients at high risk for surgical complications. Although the most commonly used approach for placement of a transcatheter aortic valve is in retrograde fashion via a transfemoral approach, narrowed luminal diameters, extensive atherosclerotic disease, or significant tortuosity may limit use of this route. In these patients, alternative methods including subclavian, transaortic, and transapical approaches should be considered. An understanding of these access routes and their respective indications and contraindications allows the radiologist to provide additional preprocedure measurements and images to help guide placement of the valve. ©RSNA, 2018.

Imaging of Lung Transplantation.

Lung transplantation is the only curative treatment for end-stage lung disease, which is caused by a wide variety of pathologies and encountered in a diverse range of patients. Potential recipients, as well as donors are carefully evaluated by imaging prior to transplant for contraindications to the transplant. After transplantation, recipients are imaged in the immediate, early, intermediate, and late periods for complications that may arise and require intervention. Radiography and computed tomography are the 2 most commonly used imaging modalities used to evaluate the chest after lung transplantation.