Seminars in nuclear medicine最新文献

Artificial intelligence (AI) has rapidly reshaped the global practice of nuclear medicine. Through this shift, the integration of AI into nuclear medicine education, clinical practice, and research has a significant impact on workforce diversity. While AI in nuclear medicine has the potential to be a powerful tool to improve clinical, research and educational practice, and to enhance patient care, careful examination of the impact of each AI tool needs to be undertaken with respect to the impact on, among other factors, diversity in the nuclear medicine workforce. Some AI tools can be used to specifically drive inclusivity and diversity of the workforce by supporting women and underrepresented minorities. Other tools, however, have the potential to negatively impact minority groups, leading to a widening of the diversity gap. This manuscript explores how various AI solutions have the potential to both negatively and positively affect diversity in the nuclear medicine workforce.

This systematic review and network meta-analysis aimed to compare the diagnostic accuracy of 2-[¹⁸F]FDG-PET/CT, ¹⁸F-NaF-PET/CT, MRI, contrast-enhanced CT, and bone scintigraphy for diagnosing bone metastases in patients with breast cancer. Following PRISMA-DTA guidelines, we reviewed studies assessing 2-[¹⁸F]FDG-PET/CT, ¹⁸F-NaF-PET/CT, MRI, contrast-enhanced CT, and bone scintigraphy for diagnosing bone metastases in high-stage primary breast cancer (stage III or IV) or known primary breast cancer with suspicion of recurrence (staging or re-staging). A comprehensive search of MEDLINE/PubMed, Scopus, and Embase was conducted until February 2024. Inclusion criteria were original studies using these imaging methods, excluding those focused on AI/machine learning, primary breast cancer without metastases, mixed cancer types, preclinical studies, and lesion-based accuracy. Preference was given to studies using biopsy or follow-up as the reference standard. Risk of bias was assessed using QUADAS-2. Screening, bias assessment, and data extraction were independently performed by two researchers, with discrepancies resolved by a third. We applied bivariate random-effects models in meta-analysis and network meta-analyzed differences in sensitivity and specificity between the modalities. Forty studies were included, with 29 contributing to the meta-analyses. Of these, 13 studies investigated one single modality only. Both 2-[¹⁸F]FDG-PET/CT (sensitivity: 0.94, 95% CI: 0.89-0.97; specificity: 0.98, 95% CI: 0.96-0.99), MRI (0.94, 0.82-0.98; 0.93, 0.87-0.96), and ¹⁸F-NaF-PET/CT (0.95, 0.85-0.98; 1, 0.93-1) outperformed the less sensitive modalities CE-CT (0.70, 0.62-0.77; 0.98, 0.97-0.99) and bone scintigraphy (0.83, 0.75-0.88; 0.96, 0.87-0.99). The network meta-analysis of multi-modality studies supports the comparable performance of 2-[¹⁸F]FDG-PET/CT and MRI in diagnosing bone metastases (estimated differences in sensitivity and specificity, respectively: 0.01, -0.16 - 0.18; -0.02, -0.15 - 0.12). The results from bivariate random effects modelling and network meta-analysis were consistent for all modalities apart from ¹⁸F-NaF-PET/CT. We concluded that 2-[¹⁸F]FDG-PET/CT and MRI have high and comparable accuracy for diagnosing bone metastases in breast cancer patients. Both outperformed CE-CT and bone scintigraphy regarding sensitivity. Future multimodality studies based on consented thresholds are warranted for further exploration, especially in terms of the potential role of ¹⁸F-NaF-PET/CT in bone metastasis diagnosis in breast cancer.

Total-body (TB) positron emission tomography (PET) scanners are classified by their axial field of view (FOV). Long axial field of view (LAFOV) PET scanners can capture images from eyes to thighs in a one-bed position, covering all major organs with an axial FOV of about 100 cm. However, they often miss essential areas like distal lower extremities, limiting their use beyond oncology.TB-PET is reserved for scanners with a FOV of 180 cm or longer, allowing coverage of most of the body. LAFOV PET technology emerged about 40 years ago but gained traction recently due to advancements in data acquisition and cost. Early research highlighted its benefits, leading to the first FDA-cleared TB-PET/CT device in 2019 at UC Davis. Since then, various LAFOV scanners with enhanced capabilities have been developed, improving image quality, reducing acquisition times, and allowing for dynamic imaging. The uEXPLORER, the first LAFOV scanner, has a 194 cm active PET AFOV, far exceeding traditional scanners. The Panorama GS and others have followed suit in optimizing FOVs. Despite slow adoption due to the COVID pandemic and costs, over 50 LAFOV scanners are now in use globally. This review explores the future of LAFOV technology based on recent literature and experiences, covering its clinical applications, implications for radiation oncology, challenges in managing PET data, and expectations for technological advancements.

The combined use of Positron Emission Tomography (PET) and Computed Tomography (CT) has become increasingly vital for diagnosing and managing oncological and infectious diseases in pediatric patients. The introduction of long axial field-of-view (LAFOV) PET/CT scanners, also known as "Total Body PET/CT," marks a significant advancement in nuclear medicine. This new technology enables faster pediatric imaging with substantially reduced radiation exposure and essentially eliminates the need for sedation, addressing previous critical concerns in pediatric imaging. This review will explore the applications and challenges of LAFOV PET/CT in pediatric imaging, highlight the benefits observed at two Danish hospitals, and evaluate its potential to transform the management of pediatric patients.

Positron emission tomography / computed tomography (PET/CT) plays a pivotal role in the assessment of cardiovascular diseases (CVD), particularly in the context of ischemic heart disease. Nevertheless, its application in other forms of CVD, such as infiltrative, infectious, or inflammatory conditions, remains limited. Recently, PET/CT systems with an extended axial field of view (LAFOV) have been developed, offering greater anatomical coverage and significantly enhanced PET sensitivity. These advancements enable head-to-pelvis imaging with a single bed position, and in systems with an axial field of view (FOV) of approximately 2 meters, even total body (TB) imaging is feasible in a single scan session. The application of LAFOV PET/CT in CVD presents a promising opportunity to improve systemic cardiovascular assessments and address the limitations inherent to conventional short axial field of view (SAFOV) devices. However, several technical challenges, including procedural considerations for LAFOV systems in CVD, complexities in data processing, arterial input function extraction, and artefact management, have not been fully explored. This review aims to discuss the technical aspects of LAFOV PET/CT in relation to CVD by highlighting key opportunities and challenges and examining the impact of these factors on the evaluation of most relevant CVD.

Positron Emission Tomography (PET) is a crucial imaging modality in oncology, providing functional insights by detecting metabolic activity in tissues. Total-body (TB) PET and large field-of-view PET have emerged as advanced techniques, offering whole-body imaging in a single acquisition. TB PET enables simultaneous imaging from head to toe, providing comprehensive information on tumor distribution, metastasis, and treatment response. This is particularly valuable in oncology, where metastatic spread often requires evaluation of multiple body areas. By covering the entire body, TB PET improves diagnostic accuracy, reduces scan time, and increases patient comfort. Furthermore, these new tomographs offer a marked increase in sensitivity, thanks to their ability to capture a larger volume of data simultaneously. This heightened sensitivity enables the detection of smaller lesions and more subtle metabolic changes, improving diagnostic accuracy in the early stages of cancer or in the evaluation of minimal residual disease. Moreover, the increased sensitivity allows for lower radiotracer doses without compromising image quality, reducing patient exposure to radiation or very quick acquisitions. Another significant advantage is the possibility of dynamic acquisitions, which allow for continuous monitoring of tracer kinetics over time. This provides critical information about tissue perfusion, metabolism, and receptor binding in real time. Dynamic imaging is particularly useful for assessing treatment response in oncology, as it enables the evaluation of tumor behavior over a period rather than a single static snapshot, offering insights into tumor aggressiveness and potential therapeutic targets. This review is focused on the current applications of TB and large field-of-view PET scanners in oncology.