Radiographics最新文献

Due to longer survival of patients with cancer, better recognition and understanding of immunocompromising conditions, and emerging immune-modulating therapies for malignant and nonmalignant diseases, the number of immunocompromised individuals has increased. Immunocompromised patients require complex, often individualized, evaluation and treatment of an expanded spectrum of pathogens. Pneumonia is a leading cause of death due to infectious disease in these patients, and identification of the pathogen is key to providing appropriate therapy. One important factor in evaluating an immunocompromised patient with pneumonia is the type of immunocompromise, because this will help determine the potential opportunistic agents that should be included in the differential diagnosis. Radiologists can play a vital role in the diagnosis of a wide range of pulmonary diseases associated with immunocompromise, including many opportunistic pulmonary infections, by recognizing key imaging features. The authors summarize the types of immunocompromise encountered in different clinical settings and associate these with specific opportunistic organisms, describe patterns of disease seen in patients with HIV infection with different CD4 cell counts, and describe the imaging appearance of viral and fungal infections in patients with neutropenia. ^©RSNA, 2025.

US is an important diagnostic tool in evaluation of the pancreas, as it is noninvasive, does not require irradiation, and offers real-time imaging capability and broad accessibility. Despite the utility of pancreatic US, it often has limited effectiveness due to the complex anatomy of the pancreas and peripancreatic structures, which inevitably leads to diagnostic errors. The authors summarize the lessons learned from quality assurance rounds at a high-volume tertiary care center. The errors are systematically categorized as perceptual, interpretive, information transfer, and process errors. Each error type is discussed with detailed case studies from clinical practice to underscore common pitfalls and their impact on patient management. Perceptual errors occur when the operators overlook subtle pathologic signs due to the complex anatomy. Interpretive errors arise from misjudgments regarding the clinical significance of visible abnormalities, while information transfer errors stem from inadequate communication of patient history or suboptimal review of previous imaging findings. Process errors reflect systemic issues related to US protocol and scanning techniques. The authors advocate having a thorough understanding of the US appearances of normal and variant pancreatic anatomy and emphasize the importance of correlating US findings with findings of complementary imaging modalities to improve diagnostic accuracy. They also highlight the need to use high-resolution US transducers, embrace new technologies, and adopt meticulous scanning techniques as valuable practical strategies to mitigate diagnostic errors. By providing a detailed analysis of cases, this review demonstrates how structured quality assurance measures and continuous education can significantly reduce diagnostic errors. These efforts are crucial in ensuring accurate diagnoses and optimizing patient outcomes. ^©RSNA, 2025 Supplemental material is available for this article.

Despite technical advances and careful preparation, motion artifacts are commonly encountered in cardiac CT. Artifacts due to patient motion or breathing are not correctable and may necessitate repeat scanning; however, cardiac motion artifacts may be mitigated without repeating the scan. Cardiac motion artifacts may manifest as blur, transition, interpolation, or duplication. Blur artifact due to mismatch between cardiac motion speed and the scanner's temporal resolution can be mitigated by using a different cardiac phase, a motion-correction algorithm, or multisegment reconstruction. Transition artifact at the interface between different scanned segments with different R-R interval lengths may be mitigated by using a different cardiac phase or edge-correction algorithms. Interpolation artifact results when the pitch is too high for the heart rate (HR) at some point of a retrogated scan, either due to the patient taking a deep breath, missing electrocardiographic (ECG) synchronization (sync)-points, or long ECG pauses after premature atrial contractions (PACs) or premature ventricular contractions (PVCs). The scanner fills the data gaps by interpolating (ie, "smearing") data from above and below the gap. Duplication artifact results when the pitch is too low for the HR at some point of a retrogated scan, due to contrast material injection, medications, premature or extra beats, or spurious ECG sync-points. Interpolation and duplication artifacts can often be mitigated by manipulating ECG sync-points. In sync-point editing, sync-points are added (eg, for a missed R wave) or deleted (eg, tagging of a tall T wave, exercise spike, or bifid R waves) such that every R wave (and only R waves) are tagged. In sync-point composing, sync-points are artificially manipulated to improve image quality in arrhythmias with variable R-R intervals (eg, PACs or PVCs, atrial fibrillation). ^©RSNA, 2025 Supplemental material is available for this article. See the invited commentary by Ufuk and Landeras in this issue.

Bone surface lesions are those that originate at or adjacent to the cortex. They include a variety of benign and malignant tumors, as well as nonneoplastic entities such as infectious, posttraumatic, and developmental lesions. Many of these lesions arise from certain layers from within or about the cortex and have features dictated by the layer from which they arise. Knowledge of the different cell types and cortical bone surface anatomy equips radiologists with the ability to provide a useful differential diagnosis for these lesions. The authors review the important anatomic and imaging features that radiologists can use to evaluate bone surface lesions. ^©RSNA, 2025 Supplemental material is available for this article.

Surgical approaches to lung cancer resection are rapidly evolving, particularly for early-stage lung cancer. Advances in chest CT technology and increasing use of CT in patient care have led to detection of smaller nodules, many with ground-glass attenuation that do not require lobectomy for resection. Lung-sparing and minimally invasive techniques have been shown to result in improved patient outcomes compared with those of traditional open thoracotomy and are noninferior in terms of cancer recurrence. As more patients undergo these surgeries, it is important for radiologists to be aware of useful information for surgeons before the operation. It is helpful for radiologists to understand the indications for lung-sparing surgery and have a basic understanding of the techniques involved in video-assisted and robotic thoracic operations. Identification of the location and morphology of the tumor, as well as the pulmonary vasculature that feeds and drains the segment of lung containing the tumor is important. Also, the presence of emphysema, pulmonary fibrosis, and incomplete fissures is useful information. In addition, chest imaging is also progressing, with improvements in multiplanar reformations and three-dimensional imaging allowing for more detailed and accurate image-based localization of tumors and visualization of anatomy. Nodule localization for surgery plays an even larger role given the limited ability to palpate nodules during surgery with minimally invasive surgery approaches. Methods can involve imaging and in vivo localization, with transthoracic and bronchoscopic methods used to label a nodule. Finally, radiologists should be aware of postoperative complications and their imaging characteristics, such as suture line granulomas and bronchopleural fistulas. Supplemental material is available for this article. ^©RSNA, 2025.

Reverse total shoulder arthroplasty (RTSA) is increasingly used for a variety of complex shoulder abnormalities, particularly in patients with rotator cuff deficiency. Design improvements with better biomechanics have led to improved clinical outcomes, but the radiographic appearance and complication profile of contemporary RTSA implants differ from those of a decade ago. Plain radiographs can be used to identify whether the prosthesis is medialized (primarily older prostheses) or lateralized. A standardized imaging protocol and a reporting checklist are vital for the identification of complications. Although most complications can be identified with standard radiography, CT and MRI performed with dedicated protocols to reduce metallic artifacts are helpful problem-solving adjuncts. US can be used to assess the surrounding muscles before and after RTSA, to evaluate for postoperative complications such as fluid collections, and to provide guidance for aspiration. Complications such as periprosthetic fracture, instability, loosening, scapular notching, and implant failure require focused search patterns for identification. More chronic complications such as stress fractures and tuberosity fragmentation require comparison with previously acquired images. Implant disassembly, rarely seen with other arthroplasties, can occur and requires familiarity with the expected appearance of the prosthesis components. A downloadable checklist for imaging evaluation of the prosthesis is provided, and imaging examples of common and uncommon complications are presented. After reviewing this article, the reader will have an improved understanding of the RTSA prosthesis and will be able to recognize the normal and abnormal imaging appearances of this increasingly popular type of shoulder replacement. ^©RSNA, 2025 Supplemental material is available for this article.

PET/MRI has been established as a clinical imaging modality with a wide range of applications. In pediatric imaging, it has been shown to provide valuable diagnostic information for a variety of indications and clinical questions. Despite the increasing availability of clinical PET/MRI, its routine use for pediatric patients is still primarily limited to large clinical and academic centers. One reason is the high complexity of pediatric PET/MRI, which requires thorough patient preparation and examination planning, skilled image acquisition, and careful image interpretation. The authors provide practical guidance to support the clinical implementation of pediatric PET/MRI and thus increase its availability to pediatric patients. To this end, the authors provide an overview of technical prerequisites, imaging protocols, clinical indications, and image analysis strategies. These aspects are illustrated with clinical examples provided by established clinical pediatric PET/MRI programs worldwide. ^©RSNA, 2025 Supplemental material is available for this article.

Neoadjuvant therapy (NAT) for patients with rectal cancer is intended to reduce the risk of local recurrence and distant metastasis while preserving quality of life. Choosing the optimal approach after NAT is complex, requiring a personalized plan that considers the unique characteristics of each patient and their tumor, as well as the resources and capabilities of the treating institution. Advances in treatment, guided by insights from randomized clinical trials and increasing acceptance of organ preservation strategies, also known as nonoperative management or the watch-and-wait approach, emphasize the importance of precise treatment response assessment and multidisciplinary communication. A comprehensive evaluation using digital rectal examination, endoscopy, and MRI with a dedicated rectal cancer protocol ensures accurate clinical and locoregional response assessment. This integrative approach enables clinicians to make decisions regarding organ preservation, surgery, treatment de-escalation, or even additional NAT, with MRI having a critical role in surgical planning when resection is needed. The authors provide a comprehensive guide for interpreting postneoadjuvant rectal cancer MRI and applying the Society of Abdominal Radiology Colorectal and Anal Cancer Disease-focused Panel (SAR DFP) synoptic MRI restaging report template. The aim is to improve the quality, consistency, and clarity of MRI interpretations across different readers and institutions. Each section corresponds to the SAR DFP synoptic MRI restaging report template, addressing common areas of confusion and providing essential background material to ensure that clinically relevant information is clearly communicated to the treatment team, supporting effective decision making and enhancing patient outcomes. ^©RSNA, 2025 Supplemental material is available for this article.