Search Results (83)

Amyloid positron emission tomography (PET) has become a critical tool in the diagnosis and treatment of Alzheimer’s disease (AD). The Centiloid (CL) scale, a tracer/scanner-independent, standardized quantification unit introduced in 2015, transforms tracer- and scanner-specific standardized uptake value ratios (SUVRs) into a common metric anchored at 0 CL in young cognitively unimpaired individuals and 100 CL in patients with mild-to-moderate AD. This review synthesizes current evidence on the clinical role of the CL scale across three domains: (1) diagnostic classification, with established thresholds of <10 CL for amyloid negativity and >30 CL for high-certainty amyloid positivity; (2) treatment eligibility, where a 2024 Alzheimer’s Association Research Roundtable consensus of global experts recommended a 24–30 CL threshold for initiating lecanemab or donanemab therapy in patients with mild cognitive impairment (MCI) or mild AD dementia; and (3) longitudinal therapy monitoring, in which serial CL measurements provide objective evidence of amyloid clearance. We also review the emerging ‘gray zone’ (10–30 CL) as a distinct clinical entity with elevated progression risk, the critical role of CL quantification in complementing visual reads in borderline cases, technical limitations, and the future integration of CL in clinical practice. This review also critically addresses the ongoing debate on whether amyloid clearance represents a reliable surrogate for clinical benefit, strategies for managing discordant biomarker findings, and the practical feasibility of serial amyloid PET in routine care. With FDA approval of both lecanemab and donanemab, familiarity with the CL scale as a functional treatment biomarker is increasingly relevant for neuroradiologists and nuclear medicine physicians in the modern AD care pathway. As with all imaging modalities, the CL has physiologic and technical limitations. Although the CL scale was designed to reduce heterogeneity across tracers and scanner platforms, the impact of different commercial quantification software packages on CL output remains incompletely characterized. Consistent use of a single software platform for longitudinal monitoring in individual patients is therefore recommended. Full article

The coronary arteries are a pair of arteries that branch off from the aorta and encircle the heart, providing oxygenated blood to the myocardium. Although coronary artery atherosclerosis remains a main cause of morbidity and mortality worldwide, coronary artery anomalies (CAAs) are increasingly recognized as a clinically relevant cause of ischemic events and can be subdivided into origin, course, or termination anomalies. The aim of this narrative review is to summarize the cross-sectional diagnostic imaging and clinical background of CAAs. Full article

In medicine, nanoparticles are used for various purposes, including theranostics, imaging, diagnostics, drug delivery, tissue regeneration and targeted cancer treatments, and to minimize the harmful side effects associated with conventional therapies. Target-specific biomolecules, such as silica nanoparticles (SiNPs) labeled with metallic radionuclides, are becoming increasingly popular. The choice of radionuclide is based on its nuclear properties. Silica has several advantages for nanoparticle synthesis, including high biocompatibility, the capacity for drug encapsulation due to its porous structure, and the potential for extensive surface functionalization, including radiolabeling for imaging and therapeutic applications. A radionuclide can be attached to a silica nanoparticle either directly or through the use of chelators or polymers. Additionally, the capability to encapsulate therapeutic agents within such systems offers significant potential for the development of targeted therapies. This study aims to provide a comprehensive overview of recent developments in the radiolabeling of silica-based nanoparticles, with a focus on their application in nuclear medicine, particularly in diagnostic imaging and targeted radionuclide therapy. Theranostics employs a range of imaging modalities to guide and monitor therapeutic interventions. Principal techniques include positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), and Optical Imaging (such as fluorescence and bioluminescence). These imaging methods enable precise visualization of pathological sites, facilitate tracking of therapeutic agent distribution, and permit real-time assessment of treatment efficacy. Full article

Background: Magnetic particle imaging (MPI) is an emerging, tracer-based modality that directly detects superparamagnetic iron oxide nanoparticles (SPIONs) with exceptional sensitivity, quantitative signal behavior, and full immunity to air–tissue susceptibility artifacts. These features make MPI particularly well-suited for pulmonary imaging, where traditional techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine-based ventilation/perfusion (V/Q) imaging are limited by radiation exposure, low contrast, and motion-related signal degradation. Objective: This review synthesizes the current state of MPI for lung imaging, with emphasis on its physical principles, tracer development, preclinical applications, and its potential role in assessing pulmonary perfusion, vascular integrity, inflammation, and therapeutic responses. Methods: A systematic evaluation of preclinical studies was performed across three major application domains: pulmonary perfusion mapping, cell tracking and therapeutic monitoring, and vascular injury and permeability assessment. Study designs, SPION formulations, MPI acquisition strategies, and validation methods, including histopathology, biodistribution, broncho-alveolar lavage fluid (BALF) analysis, and Evans Blue assays, were examined to characterize methodological consistency and imaging performance. Results: MPI consistently demonstrated high-contrast, quantitative visualization of pulmonary blood flow, endothelial barrier disruption, inflammatory signaling, and transplanted or inhaled cell populations. Tracer engineering played a critical role: macroaggregated albumin superparamagnetic iron oxide nanoparticles (MAA-SPIONs) enabled capillary-level perfusion mapping, LS-008 improved temporal resolution and vascular delineation, Synomag/Synomag-D allowed quantification of vascular leakage in acute and chronic lung injury, and vascular cell adhesion molecule-1 (VCAM-1)-targeted probes provided molecular-level assessment of inflammation. Hybrid MPI-CT and MPI-MRI approaches further enhanced anatomic localization and enabled accurate pulmonary blood volume (PBV) estimation. Across studies, MPI measurements showed strong agreement with established biological assays and remained free of the artifacts that limit CT and MRI in the lung. Conclusions: Preclinical evidence demonstrates that MPI is a robust, radiation-free, and quantitatively precise modality for functional and molecular lung imaging. Its ability to map perfusion, track therapeutic agents, and noninvasively quantify vascular permeability positions MPI as a promising future alternative or complement to CT, MRI, and nuclear medicine for pulmonary assessment. Continued tracer optimization, system scaling, and clinical validation are key steps toward translating MPI into routine clinical use. Full article

Breast-conserving therapy, consisting of lumpectomy followed by adjuvant radiotherapy, is the standard of care for early-stage breast cancer, providing oncologic outcomes equivalent to mastectomy while preserving breast anatomy and quality of life. Radiotherapy remains a cornerstone of treatment across disease stages, significantly reducing local recurrence rates and improving long-term survival. Advances in radiotherapy techniques—including conventional fractionation, hypofractionation, tumor-bed boost delivery, and regional nodal irradiation—have optimized oncologic efficacy while inducing a broad spectrum of time-dependent morphological changes in breast tissue. Accurate imaging surveillance is therefore essential to distinguish expected post-radiotherapy changes from tumor recurrence and to avoid unnecessary diagnostic or therapeutic interventions. This review provides a comprehensive overview of contemporary breast radiotherapy protocols, their impact on post-treatment imaging appearances, and current recommendations for imaging surveillance. Characteristic findings across mammography, ultrasound, magnetic resonance imaging, and nuclear medicine modalities are discussed, with emphasis on their temporal evolution from acute inflammatory changes to chronic fibrosis, fat necrosis, and architectural distortion. Recognition of these imaging patterns, together with integration of radiotherapy-related parameters into image interpretation, is crucial for accurate diagnosis, early detection of recurrence, and informed clinical management of breast cancer survivors. Full article

Infective endocarditis (IE) is a severe infectious disease affecting cardiac valves (either native or prosthetic) or implantable cardiac devices, and it is associated with high rates of morbidity and mortality. Recent data from the Global Burden of Disease study have shown a significant increase in both the incidence and mortality of IE. One-year mortality following diagnosis can reach up to 30%. IE can present with a wide range of clinical manifestations, and its course may be complicated by systemic embolic events or intracardiac complications such as abscess formation or prosthetic valve dehiscence. Echocardiography remains the first-line imaging modality; however, an integrated multimodality imaging approach is increasingly adopted in contemporary practice, incorporating both cardiac computed tomography and positron emission tomography. A multidisciplinary approach involving cardiologists, cardiac surgeons, internists, infectious disease specialists, and nuclear medicine physicians is often required to ensure accurate diagnosis and effective treatment of IE. The prognosis of infective endocarditis depends on early diagnosis, appropriate antimicrobial therapy, and timely surgical intervention when indicated. This review aims to summarize the current knowledge on IE, from pathophysiological insights to surgical strategies. It also focuses on practical recommendations to address the most pressing unmet clinical needs through a multidisciplinary approach. Full article

Background: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by immune dysregulation and systemic inflammation, with the cardiovascular (CV) system representing a major yet frequently under-recognized target. Cardiac involvement spans from subclinical myocardial inflammation to overt pericardial disease, myocarditis, valvular abnormalities, coronary microvascular dysfunction, and accelerated atherosclerosis. Given that CV disease remains a leading cause of morbidity and mortality in SLE, early detection of silent cardiac injury is crucial. Aim: This review aims to provide a comprehensive and clinically oriented overview of CV involvement in SLE, focusing on the role of multimodal cardiac imaging in the detection, characterization, and risk stratification of cardiac abnormalities, as well as its potential implications for clinical management and preventive strategies. Methods: This narrative review is based on a structured, non-systematic search of PubMed (2013–2026), combining the term “systemic lupus erythematosus” with imaging-related keywords including “transthoracic echocardiography,” “cardiac magnetic resonance,” and “cardiac computed tomography.” English-language studies in adult populations were screened and selected according to clinical relevance, methodological robustness, and contribution to understanding SLE-related cardiac involvement. Discussion: Multimodal cardiac imaging plays a central role in the evaluation of SLE-related cardiac disease. Transthoracic echocardiography (TTE) represents the first-line modality for the assessment of ventricular function, pericardial disease, and valvular abnormalities, while deformation imaging enables the detection of subtle myocardial dysfunction. Cardiac magnetic resonance (CMR) provides comprehensive tissue characterization, allowing differentiation between active inflammation and chronic fibrosis. Cardiac computed tomography (cCT) identifies subclinical coronary atherosclerosis and high-risk plaque features, whereas nuclear imaging techniques offer insight into inflammatory activity and microvascular dysfunction. Conclusions: An integrated, imaging-based approach enables early diagnosis, refined CV risk stratification, longitudinal monitoring, and personalized therapeutic strategies. Multimodal imaging thus represents a key pillar of precision medicine in lupus-associated CV disease. Full article

PET scans have long been used in oncology imaging to provide molecular and metabolic information about diseases. The use of artificial intelligence (AI) in PET scans in oncology theranostics has the potential to optimise PET modality and overcome the constraints that PET scans have, such as semi-quantitative metrics, reader subjectivity, and variability across scanners/institutions. Advances in AI and radiomics are overcoming those limitations by deep learning lesion detection, enhancing image reconstruction, and improving noise resolution, which allows ultra-low dose acquisitions, while physics-informed models integrate with PET systems to strengthen interpretability and quantitative accuracy. There are also predictive AI frameworks that link PET imaging biomarkers to therapy response and outcomes, create individualised care and are even able to simulate treatment response and help with treatment planning. However, challenges do exist. Most AI PET studies are retrospective, single-centre, and underpowered (small sample), with limited external validation and inconsistent standardisation (in acquisition, segmentation, and extraction), leading to poor reproducibility and higher performance estimates. Furthermore, ethical considerations, including data protection and transparency, need to be considered before implementation. Federated learning, physics-informed frameworks, and adherence to standardised protocols offer steps towards regulated AI systems. In summary, PET is evolving from an imaging modality to a platform with the integration of deep learning, radiomics and reconstruction capable of predicting treatment response and guiding treatment. With rigorous prospective validation, cross-institutional collaboration, and regulatory standardisation, AI in PET would create an advancement in nuclear medicine imaging in oncology. Full article

Moyamoya disease (MMD) is a chronic, progressive cerebrovascular disorder characterized by steno-occlusive changes in the intracranial internal carotid arteries and the development of fragile collateral networks. Imaging plays a pivotal role in diagnosis, disease staging, and management, yet the expanding range of available imaging modalities has resulted in heterogeneous evidence that remains difficult to synthesize. This scoping review aimed to systematically map and critically appraise imaging-based diagnostic approaches used in MMD, summarizing their diagnostic performance, clinical utility, and limitations. A comprehensive literature search was conducted across major databases, and original studies evaluating imaging modalities in human MMD were included. Thirty-three studies published between 1995 and 2023 were analyzed, encompassing digital subtraction angiography, magnetic resonance imaging and angiography, perfusion and functional MRI, computed tomography-based techniques, nuclear medicine, ultrasound, neurophysiological methods, and emerging artificial intelligence applications. Digital subtraction angiography remains the diagnostic reference standard, particularly for disease confirmation and surgical planning. However, noninvasive modalities provide critical complementary information. Magnetic resonance-based techniques offer multiparametric assessment of vascular morphology, hemodynamics, vessel wall pathology, and parenchymal injury. Computed tomography angiography and perfusion imaging provide accessible alternatives with high sensitivity for vascular changes, while functional and neurophysiological methods contribute additional hemodynamic and regional assessments. Artificial intelligence applications show promising diagnostic performance but remain in early validation stages. The evidence base is limited by methodological heterogeneity, inconsistent reference standards, incomplete reporting of diagnostic accuracy metrics, and a scarcity of longitudinal and multimodal studies. Collectively, the findings support a multimodal imaging strategy in MMD, integrating structural and functional information to inform diagnosis and management. Future research should prioritize standardized protocols, longitudinal designs, and clinically validated imaging biomarkers to enable evidence-based diagnostic pathways. Full article

Cardiovascular imaging is a cornerstone of modern cardiology, yet its clinical impact is limited by operator dependence, inter-observer variability, time-consuming workflows, and unequal access to advanced expertise. Artificial intelligence (AI), particularly machine learning and deep learning, offers new opportunities to overcome these limitations. This review aims to summarize current and emerging AI applications in cardiovascular imaging and to evaluate their potential clinical value in precision diagnostics and decision support. This narrative review synthesizes clinically relevant literature on AI applications across major cardiovascular imaging modalities, including echocardiography, cardiovascular magnetic resonance, cardiac computed tomography, and nuclear cardiology. Evidence was analyzed with a focus on AI-enabled acquisition support, image segmentation, quantitative and functional assessment, workflow automation, and risk stratification, alongside key methodological and implementation considerations. Across imaging modalities, AI-driven approaches have demonstrated improved reproducibility, efficiency, and scalability of cardiovascular imaging workflows. Automated algorithms reduce operator dependence, facilitate standardized extraction of imaging biomarkers, and support advanced functional assessment and prognostic stratification. Recent developments in video-based, temporal, and multimodal models further expand AI capabilities from technical automation toward integrated disease phenotyping and personalized clinical decision support. However, translation into routine practice remains limited by heterogeneous datasets, insufficient external validation, algorithmic bias, limited interpretability, and challenges related to regulatory approval and workflow integration. Artificial intelligence has the potential to reshape cardiovascular imaging into a more efficient, reproducible, and patient-centered precision medicine tool. Real-world clinical impact will depend on outcome-driven evaluation, robust external validation, multimodal data integration, and human-in-the-loop implementation strategies that ensure safe, equitable, and clinically meaningful adoption. Full article

Owing to the high pharmacological relevance and multidimensional quality attributes of Panax spp., accurate authentication and quality evaluation of Panax-derived herbal materials remain challenging within traditional Chinese medicine (TCM) quality control systems. Conventional approaches often face trade-offs among analysis speed and throughput, non-destructive measurement, and analytical accuracy, which can limit their suitability for modern, large-scale quality control. This review summarizes recent advances in vibrational and related analytical techniques—infrared (IR) and near-infrared (NIR) spectroscopy, Raman spectroscopy, terahertz (THz) spectroscopy, hyperspectral imaging (HSI), and nuclear magnetic resonance (NMR)—for authentication and quality evaluation of Panax materials. We compare the capabilities of each modality in supporting key tasks, including species authentication, geographical origin tracing, age/cultivation-stage discrimination, and quantitative assessment of major chemical markers, with emphasis on the underlying measurement principles. In general, NIR and HSI are well suited to rapid, high-throughput screening of bulk samples, whereas Raman and NMR provide higher chemical specificity for molecular and structural characterization. To mitigate limitations of single-modality analysis, this review discusses a methodological shift from conventional spectral fingerprinting and chemometric approaches toward model-driven, data-enabled sensing strategies for robust quality evaluation. Specifically, we highlight multimodal data fusion frameworks combined with interpretable machine-learning/deep-learning methods to build robust classification and regression models for quality assessment. This perspective aims to support standardized and scalable authentication and quality evaluation of Panax herbal materials and to facilitate the digitization of quality control workflows for Chinese herbal medicines. Full article

Background: Prostate-specific membrane antigen (PSMA) is markedly overexpressed in prostate cancer (PCa), and there is growing evidence to support its usefulness in initial diagnostic assessments. This study compares the diagnostic performance of PSMA positron emission tomography/computed tomography (PET/CT) and magnetic resonance imaging (mpMRI) in evaluating seminal vesicle invasion (SVI), extraprostatic extension (EPE), and pelvic lymph node involvement before radical prostatectomy. Methods: A retrospective, single-institution analysis was performed. From a cohort of 325 patients who underwent radical prostatectomy between June 2022 to November 2024, 85 had undergone preoperative PSMA PET/CT for intermediate- and high-risk disease at biopsy, forming our study group. Two blinded specialists, one in radiology and one in nuclear medicine, independently interpreted the scans, using histopathological results as the reference standard. The primary outcome was diagnostic accuracy for T- and N-stage classification, while the secondary outcomes included the correct identification of the index lesion and comparative performance for each modality. Results: The study cohort comprised patients with intermediate-to-high-risk prostate cancer (median age: 66 years; median PSA level: 11.6 ng/mL; median PSA density: 0.3 ng/mL/cm³). Forty-eight patients presented with an ISUP grade of 3 or higher on biopsy. PSMA PET/CT was more sensitive than MRI for detecting EPE (72.2% vs. 46.9%) and nodal metastases (91.7% vs. 8.3%). Furthermore, PSMA PET/CT demonstrated significantly higher concordance with histopathological findings in index tumor localization (76.5% vs. 67.9%, p < 0.001). An exploratory analysis revealed a potential age-dependent pattern, but this requires confirmation in larger studies. Conclusions: In this select cohort, PSMA PET/CT demonstrated greater accuracy than MRI for locoregional staging in patients with intermediate-to-high-risk prostate cancer (PCa). However, the generalizability of these findings is limited by the retrospective design and potential selection bias. These results suggest that PSMA PET/CT may have a valuable role in the initial staging workflow, but this needs to be confirmed in larger, prospective studies. An exploratory analysis suggested a potential age-dependent pattern, but this requires confirmation in larger studies. Full article

Parkinson’s disease (PD) is a multifaceted neurodegenerative disorder characterized by dopaminergic neuronal loss and widespread α-synuclein pathology. Nuclear medicine imaging offers essential in vivo tools for early diagnosis, differential assessment, and monitoring disease progression. This review summarizes key PET and SPECT radiotracers targeting dopaminergic synthesis and transport, vesicular storage, post-synaptic receptors, neuroinflammation, and protein aggregation, highlighting their roles in clinical evaluation and phenotyping. Clinically, these modalities support earlier recognition of PD, distinction from atypical parkinsonian syndromes, and assessment of non-motor involvement. Future directions include the development of selective α-synuclein tracers and multimodal imaging strategies to refine prodromal detection and guide personalized therapeutic interventions. Full article

Mammary gland tumors (MGT) are the most common neoplasms in intact female dogs and represent the third most frequent tumor type in female cats. Imaging plays a central role in the diagnosis, staging, and follow-up of these neoplasms. This review summarizes the diagnostic imaging features of canine and feline MGT and the advantages and limitations of each modality. Radiography and computed tomography (CT) are mainly used to detect pulmonary and abdominal metastases, while ultrasonography provides key information about primary tumor size, margins, echogenicity, vascularization, and elasticity. Advanced ultrasound techniques, such as Doppler, contrast-enhanced ultrasonography (CEUS), and elastography, improve differentiation between benign and malignant lesions. Magnetic resonance imaging (MRI) offers excellent soft-tissue detail and can assist in preoperative planning, whereas nuclear medicine techniques, including scintigraphy and positron emission tomography (PET), allow functional assessment and the early detection of micrometastases. Although histopathology remains the diagnostic gold standard, imaging is indispensable for characterizing primary lesions, evaluating metastatic spread, guiding sampling, and monitoring therapeutic outcomes in small animal oncology. By integrating and comparing the main imaging modalities applied to canine and feline mammary tumors, this review underscores their complementary roles in improving diagnosis, staging, and therapeutic decision-making in small animal oncology. Full article

Parathyroid carcinoma (PC) is an exceedingly rare endocrine malignancy, accounting for less than 1% of all primary hyperparathyroidism (pHPT) cases. It typically presents with pronounced hypercalcemia and markedly elevated parathyroid hormone (PTH) levels. Accurate imaging plays a pivotal role in diagnosis, staging, surgical planning, and long-term surveillance, although differentiating PC from benign disease on imaging remains a significant challenge. A multimodal imaging strategy combining cervical ultrasonography (US) and nuclear medicine techniques provides high sensitivity for lesion detection. Ultrasonography with advanced detective flow imaging allows detailed anatomical assessment and evaluation of vascular patterns of the primary tumor. [^99mTc]Tc-methoxyisobutylisonitrile ([^99mTc]Tc-MIBI) scintigraphy frequently demonstrates prolonged tracer retention in PC, while [¹⁸F]fluorocholine positron emission tomography/computed tomography (PET/CT) and positron emission tomography/magnetic resonance (PET/MR) imaging have shown superior performance for detecting both primary tumors and metastatic disease due to its higher spatial resolution and higher molecular sensitivity. [¹⁸F]FDG PET serves as an adjunct modality for identifying aggressive, metabolically active lesions. Emerging radiotracers such as [¹⁸F]-fibroblast activation protein inhibitor ([¹⁸F]FAPI) and [⁶⁸Ga]Ga-trivehexin have shown potential in cases where initial imaging is inconclusive. Theranostic strategies that integrate molecular imaging with targeted radioligand therapy may transform PC management by enabling personalized treatment approaches tailored to each tumor’s biological and imaging characteristics. This review aims to evaluate available imaging modalities for PC diagnosis and provide guidance for their clinical application. Full article