CT evaluation of self-induced and retained foreign bodies in the abdomen and pelvis.

Computed tomography (CT) can both locate and identify foreign bodies as well as pinpoint complications to help direct treatment. Retained foreign bodies in the abdomen and pelvis can lead to perforation, obstruction, intussusception, fistula formation, and abdominal abscess formation. This article reviews the imaging appearance of incidentally found common foreign bodies and the role of CT in identifying unsuspected foreign bodies.

Postoperative Spinal CT: What the Radiologist Needs to Know.

During the past 2 decades, the number of spinal surgeries performed annually has been steadily increasing, and these procedures are being accompanied by a growing number of postoperative imaging studies to interpret. CT is accurate for identifying the location and integrity of implants, assessing the success of decompression and intervertebral arthrodesis procedures, and detecting and characterizing related complications. Although postoperative spinal CT is often limited owing to artifacts caused by metallic implants, parameter optimization and advanced metal artifact reduction techniques, including iterative reconstruction and monoenergetic extrapolation methods, can be used to reduce metal artifact severity and improve image quality substantially. Commonly used and recently available spinal implants and prostheses include screws and wires, static and extendable rods, bone grafts and biologic materials, interbody cages, and intervertebral disk prostheses. CT assessment and the spectrum of complications that can occur after spinal surgery and intervertebral arthroplasty include those related to the position and integrity of implants and prostheses, adjacent segment degeneration, collections, fistulas, pseudomeningoceles, cerebrospinal fluid leaks, and surgical site infections. Knowledge of the numerous spinal surgery techniques and devices aids in differentiating expected postoperative findings from complications. The various types of spinal surgery instrumentation and commonly used spinal implants are reviewed. The authors also describe and illustrate normal postoperative spine findings, signs of successful surgery, and the broad spectrum of postoperative complications that can aid radiologists in generating reports that address issues that the surgeon needs to know for optimal patient management.©RSNA, 2019.

High-Value Multidetector CT Angiography of the Superior Mesenteric Artery: What Emergency Medicine Physicians and Interventional Radiologists Need to Know.

The superior mesenteric artery (SMA) provides vital blood supply to the midgut, and an acute abnormality can rapidly precipitate bowel ischemia and infarction and lead to morbidity and mortality. Vascular diseases that acutely compromise the SMA threaten its tributaries and include occlusion, dissection, aneurysm rupture, pseudoaneurysm, vasculitis, and SMA branch hemorrhage into the bowel. Emergency medicine physicians rely on the radiologist to identify SMA abnormalities, to characterize them, and to detail findings that guide the appropriate triage of these patients. As such, radiologists must be cognizant of the features that influence patient treatment to assist vascular surgeons and interventional radiologists in decision making. Some patients can be treated medically, while clinical and radiographic findings may suggest the need for interventional or surgical repair of the artery. In the latter case, multidetector CT findings aid in determining which of the various surgical and endovascular treatment options is optimal, and both vascular and gastrointestinal sequelae of acute SMA abnormalities contribute to these determinations. The authors review acute life-threatening conditions involving the SMA including acute occlusion, dissection, aneurysm, pseudoaneurysm, and hemorrhage and discuss the vascular and gastrointestinal multidetector CT findings in each of these conditions that help to guide surgical and interventional management. ©RSNA, 2019.