BACKGROUND:Hereditary transthyretin amyloidosis (ATTRv) is a multisystem disorder caused by misfolded TTR deposition, leading to neuropathy and cardiomyopathy. Early identification of subclinical involvement remains difficult. We evaluated cardiac sympathetic innervation and small fiber neuropathy in symptomatic patients and asymptomatic carriers (AC) using 123I-metaiodobenzylguanidine (123I-mIBG) scintigraphy, skin biopsy and nerve conduction studies to assess cutaneous silent period (CSP). METHODS:In this cross-sectional study, 14 symptomatic patients, 18 AC and 32 healthy controls (HC) underwent 123I-mIBG imaging to determine early and late heart-to-mediastinum ratios (e-H/M, l-H/M) and summed scores (ESS, LSS). Skin biopsies quantified intraepidermal (IENFD) and piloerector muscle nerve fiber density (PMNFD) in upper and lower limbs. Cutaneous silent period (CSP) assessed A-δ fiber function. Correlations between 123I-mIBG and years from predicted age of disease onset (delta-PADO) were analyzed in AC. RESULTS:l-H/M was reduced in AC versus HC (1.73 ± 0.23 vs 1.94 ± 0.19; p < 0.05) and further in patients (1.37 ± 0.25; p < 0.01). Delta-PADO correlated with e-H/M (p < 0.05), ESS (p < 0.01) and LSS (p < 0.01). Half of AC showed reduced lower-limb IENFD. CSP latencies were prolonged or absent in advanced cases. CONCLUSION:Reduced l-H/M indicates early cardiac sympathetic denervation in AC, preceding clinical symptoms. Combined 123I-mIBG and skin biopsy improves early detection and risk stratification in ATTRv.

We compared a novel deep learning (DL)-based quantification software (BTXBrain) with an established platform (Q.Brain) for quantitative perfusion single photon emission computed tomography (SPECT) in patients with clinically confirmed neuropsychiatric systemic lupus erythematosus (NPSLE). This retrospective exploratory inter-platform comparison study included patients with clinically established NPSLE who underwent brain SPECT with technetium-99m ethyl cysteinate dimer (99mTc-ECD). SPECT datasets were reprocessed using BTXBrain and Q.Brain. Regional perfusion estimates were compared across predefined cortical territories using paired analyses, variance ratio assessments, and Kendall’s tau correlation analysis. A total of 540 paired regional and hemispheric evaluations from 30 NPSLE patients were successfully processed and analyzed. BTXBrain and Q.Brain unveiled systematic, region-specific divergence in perfusion metrics. BTXBrain yielded higher standardized uptake value ratio values than Q.Brain in frontal (mean difference 0.081, p < 0.001), posterior cingulate (0.090, p < 0.001), medial temporal (0.333, p < 0.001), and occipital regions (0.078, p < 0.001). Conversely, a reversed trend was observed in the right lateral parietal cortex (-0.056, p = 0.009). Variance ratio analysis confirmed that the DL-based approach introduces a significantly different data dispersion profile (p < 0.05 across multiple macro-regions), while meaningful cross-platform correlation was restricted to specific territories, such as the left posterior cingulate cortex (τ = 0.44, p = 0.002). BTXBrain and Q.Brain are not directly interchangeable in patients with NPSLE. Consequently, rather than a generic drop-in replacement, the routine clinical adoption of DL-driven SPECT quantification requires software-specific reference thresholds and further calibration before cross-platform use.

We previously proposed that a probability-based sympathetic 123I-meta-iodobenzylguanidine (mIBG) index (SMILe) could distinguish the presence or absence of Lewy body disease (LBD) based on findings at a single center. However, whether the model would be useful in the real world remained uncertain. Therefore, we updated and evaluated its performance at five Japanese and three European institutions. We compared data from 967 patients with suspected LBD with 62 controls from a normal database (NDB). Of 815 patients with guideline-based diagnoses, 483 had LBD (Parkinson disease [PD] or dementia with Lewy bodies [DLB]) and 332 did not have LBD. Heart-to-mediastinum (H/M) ratios were standardized using a phantom-based method. Logistic regression models included early and late H/M ratios, age, sex, and comorbidities. We assessed diagnostic performance using ROC analysis and cross-validation. The updated model discriminated LBD from other diseases (AUC for early and late H/M, 0.880 0.899, respectively). Age correction of H/M ratios based on the NDB did not improve accuracy. Median early H/M ratios [SMILe probability] were 3.09 [12.8

To assess machine learning (ML) classifiers trained on harmonised multicentre ¹²³I-mIBG planar scintigraphy for differentiating Parkinson’s disease (PD) from non-PD parkinsonian syndromes and to determine whether early imaging alone may ensure accurate discrimination. This retrospective study included patients with suspected PD who underwent early ( 15 min) and delayed ( 240 min) imaging and received a definitive diagnosis after ≥ 12 months. Harmonised region of interest (ROI) placement and ComBat correction were applied. Early and late heart-to-mediastinum (H/M) ratios and washout rate (WR) were calculated. Differences were tested by Mann-Whitney U test, and cut-points identified by ROC analysis. Logistic regression, Gaussian naïve Bayes, and support vector machine were trained on these features with Z-score normalisation and synthetic minority oversampling technique (SMOTE). 127 patients were analysed (85 PD, 42 non-PD). Early and late H/M ratios were significantly lower in PD than non-PD (early H/M 1.45 ± 0.20 vs. 1.80 ± 0.20; late H/M 1.33 ± 0.22 vs. 1.68 ± 0.21; both p < 0.001). WR was modestly higher in PD (8.74 ± 5.76

Sentinel lymph node biopsy (SLNB) represents the current standard procedure for regional nodal staging in patients with clinically localized cutaneous melanoma. This AIMN practical guide provides an updated overview of the role of nuclear medicine in the sentinel lymph node procedure, integrating recommendations from major international guidelines and current clinical practice. The document describes indications, contraindications, radiopharmaceuticals, and technical aspects of lymphoscintigraphy, including radiotracer administration, imaging protocols, and interpretation criteria. Particular attention is devoted to the contribution of hybrid imaging techniques, especially SPECT/CT, which improve sentinel node detection and anatomical localization, thereby facilitating surgical planning. The guide also addresses intraoperative radioguided detection using handheld gamma probes, as well as relevant radiation safety considerations. By standardizing preoperative mapping and promoting multidisciplinary collaboration between nuclear medicine physicians and surgeons, these recommendations aim to optimize diagnostic accuracy and enhance the clinical management of melanoma patients undergoing SLNB.

Radium-223 (223Ra) was the first radioactive isotope approved for treating castration-resistant prostate cancer (CRPC) with symptomatic bone metastases without visceral metastatic disease. To better understand the action of 223Ra, its role in the tumor microenvironment represents a crucial aspect. A literature search was conducted using the PubMed/MEDLINE database and studies regarding the relationship between 223Ra and the tumoral microenvironment were considered. The tumoral microenvironment is a complex setting in which complex interactions between cells and molecules occur. Radium-223, as an alpha-emitter, induces double-stranded DNA breaks; to potentiate this effect, it could be used in patients with genetic instability but also in combination with therapies which inhibit DNA repair, modulate the immune response, or control tumor growth. In conclusion, a few studies have taken into consideration the tumoral microenvironment in association with 223Ra. However, its understanding is a priority to better comprehend how to effectively exploit 223Ra and its action mechanism.

Background/Objectives: The prognostic value of baseline clinical parameters in predicting the survival prolonging effect of Radium-223-dichloride (223RaCl2) for metastatic castration resistant prostate cancer (mCRPC) patients has been the object of intensive research and remains an open issue. This national multicenter study aimed to corroborate the evidence of ten years of clinical experience with 223RaCl2 by collecting data from eight Italian Nuclear Medicine Units. Methods: Data from 581 consecutive mCRPC patients treated with 223RaCl2 were retrospectively analyzed. Several baseline variables relevant to the overall survival (OS) analysis were considered, including age, previous radical prostatectomy/radiotherapy, number of previous treatment lines, prior chemotherapy, Gleason score, presence of lymphoadenopaties, number of bone metastases, concomitant use of bisphosphonates/Denosumab, Eastern Cooperative Oncology Group Performance Status (ECOG-PS), as well as baseline values of hemoglobin (Hb), platelets, Total Alkaline Phosphatase (tALP), Lactate Dehydrogenase (LDH), and Prostate-Specific Antigen (PSA). Data were summarized using descriptive statistics, univariate analysis and multivariate analysis with the Cox model. Results: The median OS time was 14 months (95%CI 12-17 months). At univariate analysis age, the number of previous treatment lines, number of bone metastases, ECOG-PS, presence of lymphadenopathies at the time of enrollment, as well as baseline tALP, PSA, and Hb, were independently associated with OS. After multivariate analysis, the number of previous treatment lines (HR = 1.1670, CI = 1.0095-1.3491, p = 0.0368), the prior chemotherapy (HR = 0.6461, CI = 0.4372-0.9549, p = 0.0284), the presence of lymphadenopathies (HR = 1.5083, CI = 1.1210-2.0296, p = 0.0066), the number of bone metastases (HR = 0.6990, CI = 0.5416-0.9020, p = 0.0059), ECOG-PS (HR = 1.3551, CI = 1.1238-1.6339, p = 0.0015), and baseline values of tALP (HR = 1.0008, CI = 1.0003-1.0013, p = 0.0016) and PSA (HR = 1.0004, CI = 1.0002-1.0006, p = 0.0005) remained statistically significant. Conclusions: In the era of precision medicine and in the landscape of novel therapies for mCRPC, the prognostic stratification of patients undergoing 223RaCl2 has a fundamental role for clinical decision-making, ranging from treatment choice to optimal sequencing and potential associations. This large Italian multicenter study corroborated the prognostic value of several variables, emerging from ten years of clinical experience with 223RaCl2.

Background/Objectives: Hereditary transthyretin-mediated amyloidosis (ATTRv) is a rare disease characterized by the deposition of amyloid in the heart and peripheral nerves, particularly affecting small fibers. This study aims to evaluate autonomic cardiac involvement in ATTRv. Methods: Twelve patients with ATTRv and twelve sex- and age-matched healthy subjects underwent 123I-mIBG scintigraphy to evaluate the early and late heart-to-mediastinum ratio (eH/M and lH/M), 99mTc-HDP bone scan scintigraphy, and neurophysiological assessments. Data were analyzed in relation to functional cardiac and neurologic scales (NYHA and FAP scales). Results: Patients with ATTRv exhibited significant cardiac denervation, as demonstrated by the reduction in early and late H/M ratios compared to the control group (eH/M: 1.48 ± 0.08 vs. 1.89 ± 0.05, p < 0.001; lH/M: 1.39 ± 0.08 vs. 2.01 ± 0.05, p < 0.001). Values of eH/M and lH/M < 1.6 effectively differentiated patients with ATTRv from the healthy controls. Cardiac denervation correlated with interventricular septal thickness and the Perugini score but was not related to neurophysiological assessments or NYHA and FAP scales. Conclusions: Ultimately, 123I-mIBG scintigraphy is an effective tool for assessing cardiac denervation in patients with ATTRv.

Positron emission tomography (PET) imaging targeting glypican-3 (GPC3) holds promise for improving the detection and characterization of hepatocellular carcinoma (HCC). Preclinical and early clinical studies have largely utilized high-molecular-weight antibodies radiolabeled with isotopes such as 89Zr and 124I, demonstrating high affinity and tumor uptake but suffering from prolonged circulation times and suboptimal signal-to-background ratios. To address these limitations, interest has shifted toward low-molecular-weight vectors—synthetic peptides and small antibody fragments—labeled with shorter-lived radionuclides (e.g., 68Ga and 18F) to enable rapid pharmacokinetics and same-day imaging protocols. Emerging platforms such as affibodies and aptamers offer further advantages in target affinity and reduced immunogenicity. However, clinical translation requires rigorous validation: larger, histologically confirmed cohorts, head-to-head comparison with CT/MRI, and correlation with hard clinical endpoints. Moreover, leveraging GPC3 expression as a biomarker could guarantee a deeper knowledge of tumor biology—differentiation grade and vascular invasion risk—and guide theranostic strategies. While β-emitters (90Y, 177Lu) have been explored for GPC3-directed therapy, their efficacy is influenced by oxygenation and cell-cycle status, whereas α-emitters (225Ac) may overcome these constraints, albeit with challenges in radionuclide selection and daughter nuclide management. Finally, dual-targeting probes combining GPC3 and prostate-specific membrane antigen (PSMA) have demonstrated superior uptake and retention in murine models, suggesting a versatile approach for future clinical diagnostics and therapy planning.

Planar cardiac scintigraphy with [123I]I-mIBG is widely used to image myocardial sympathetic activity. In multicentre studies, different γ-cameras can cause variability in quantitative parameters. This study aimed to harmonise multicentre [123I]I-mIBG data using a custom-designed phantom and to assess its feasibility and acceptability. A ‘tube and bottle’ phantom was designed to standardise the heart-to-mediastinum (H/M) ratio across 15 centres. Each centre prepared three versions of the phantom (A, B, and C) with varying pertechnetate ([99mTc]Tc-O4-) activities, acquired static images using their own γ-camera, and uploaded DICOM data to a shared platform. In the phantom, the tube and bottle represent the heart and mediastinum, respectively, with the tube-to-bottle (T/B) ratio simulating the H/M ratio. The reference centre analysed the images and calculated the T/B ratios, applying linear regression for data harmonisation. A survey was conducted to assess the phantom’s usability. The harmonised T/B ratios for versions A and B were 20.46 ± 0.78 and 6.19 ± 0.39, respectively. The average slope and intercept of the regression line across the participating centres resulted in 1.07 ± 0.38 and − 0.82 ± 4.95. Survey feedback indicated high feasibility and acceptability, with all centres recommending the phantom for multicentre harmonisation. The custom-made phantom effectively harmonised experimental data across different centres, supporting its use in multicentre studies to improve data consistency.

Purpose Coronary artery disease (CAD) underestimation represents a major pitfall of single-photon emission computed tomography-myocardial perfusion imaging (SPECT-MPI). Coronary artery calcium score (CACS) has emerged as a sensitive tool for the assessment of suspect CAD; however, the integration of SPECT-MPI with CACS has been seldom evaluated, so far, and was therefore the aim of the present study. Methods Patients undergoing SPECT-MPI with CACS and subsequent coronary angiography were included. ROC curves were used to identify the CACS values best predictive for CAD. In SPECT-MPI negative patients, the formula: defined the optimal CACS cut-points. The Systematic Coronary Risk Evaluation 2 was applied for 10-year cardiovascular risk estimation. Significant CAD was defined for an epicardial coronary stenosis >70 or 50% for the left main. Results Among 124 patients, 61 (49.19%) displayed positive SPECT-MPI, whereas 69 (56%) had significant CAD at angiography. Sensitivity, specificity, and positive predictive value (PPV) for SPECT-MPI were, respectively, 74, 82, and 84%. Considering 63 SPECT-MPI negative cases, the index values for CACS at the optimal cutoff value of 1949 were: sensitivity 28%, specificity 89%, and PPV 50%, allowing to further detect five (8%) of the patients with significant CAD. The increased discriminative power of the combined SPECT-MPI with CACS was not conditioned by the pretest cardiovascular risk. Conclusion Among patients with suspect CAD undergoing SPECT-MPI, the addition of CACS in negative cases allows to detect a consistent further 8% of patients with significant CAD, thus limiting the risk of disease underestimation and offering potential prognostic benefits.

Background: This systematic review was performed to investigate the potential diagnostic role of fibroblast activation protein (FAP)-targeted radiopharmaceuticals in hepatocarcinoma (HCC) and cholangiocarcinoma (CCA). Methods: Relevant studies published between 2019 and 2023 were selected by searching PubMed and Scopus. The following data were extracted: authors, radiopharmaceuticals, sample size, country and year of publication, study design, and main results. Selected studies were analyzed using a modified version of the Critical Appraisal Skills Programme (CASP). Results: A total of 15 papers were finally selected, where 5 (33%) were retrospective, and 10 (67%) were prospective, with an overall number of 331 involved patients. Most of the studies (14/15, 93%) employed the FAP inhibitor series (FAPI), while only one research study used cyclic peptides as FAP-binding motifs. Twelve papers (80%) compared these FAP-targeted radiopharmaceuticals with 18F-FDG. The other 3/15 (20%) were not comparative studies and used exclusively 68Ga-FAPI-04. 68Ga-FAPI-04 is the most used radiopharmaceutical in analyzed studies (11/15, 73%), while other tracers, including 18F-FAPI, 68Ga-FAPI-46, and 68Ga-FAP-2286, were used in the remaining ones. Conclusions: FAP-targeted radiopharmaceuticals have good diagnostic accuracy in HCC and CCA, with potential and promising theragnostic applications.

Objective. In the fight against cancer, improving the detectors performance is crucial to enhance diagnostic accuracy and optimize therapeutic monitoring. Current clinical SPECT systems predominantly rely on NaI(Tl) crystals, which, despite their advantages, suffer from limited count-rate performance due to long scintillation decay times. Our goal is to address this limitation by developing an innovative class of plastic scintillators doped with high-Z elements. These materials combine the fast timing characteristics of organic scintillators with improved gamma-ray detection efficiency via enhanced photoelectric interaction probability. Methods. Our research has focused on synthesizing novel organic fluorophores to fabricate plastic scintillators doped with high-Z elements with concentrations up to 10%. Moreover, we explored different fabrication techniques, including thermal polymerisation, photoinitiated polymerisation and resin 3D-printing. Results. The resulting prototypes show promising characteristics in terms of optical transparency, dopant homogeneity, light yield and timing performance, reaching levels comparable with commercial standards. Conclusions. These novel scintillators will be at the core of a next-generation SPECT detector, in which the doped scintillators are polymerized directly into the holes of a 3D-printed tungsten collimator, with signal readout performed by tiled CMOS sensors to fully exploit the plastics’ timing properties, and FPGA modules for data pre-processing. Moreover, they will serve for the development of a compact portable dosimeter tailored for metastatic castration-resistant prostate cancer (mCRPC) patients undergoing Lu-177-PSMA-617 radio-metabolic therapy. This device is designed to retrieve the radiopharmaceutical washout curve without requiring multiple SPECT scans, in order to customize the radiopharmaceutical prescription by determining the patient-specific radiometabolic parameters.

INTRODUCTION:Photo-thermal therapy (PTT) is an emerging biomedical field involving plasmonic nanoparticles (NPs), which efficiently convert light into heat due to a phenomenon known as Localized Surface Plasmon Resonance (LSPR). The ease of surface functionalization offered, especially by gold NPs (AuNPs), significantly betters their biocompatibility and stability. The radiolabeling of AuNPs with Technetium-99 (99mTc) allows for their precise spatial localization within the body at any depth and site through nuclear medicine imaging techniques. The combination of radioactive, optical, and thermo-ablative properties makes radiolabelled AuNPs a valid tool in theranostics. This review summarizes the main concepts behind PTT and the most recent clinical applications of plasmonic 99mTc-labeled NPs in cancer theranostic. AREAS COVERED:Literature research of the last 20 years was conducted using Scopus and PubMed, including papers concerning technetium-radiolabelled NPs functionalized for cancer PTT. EXPERT OPINION:AuNPs have been the subject of extensive research for diverse biomedical applications, including cancer diagnostics, therapy, and prevention, as well as drug delivery, sensing and cellular imaging. Despite the limited number of in vivo animal studies, radiolabeling and functionalizing the AuNPs with technetium represents a promising strategy to obtain a specific and efficient theranostic tool for nuclear medicine imaging.

Background: Differentiating Parkinson’s disease (PD) from essential tremor (ET) is often challenging, especially in early or atypical cases. Dopamine transporter (DAT) single-photon emission computed tomography (SPECT) with 123I-Ioflupane supports diagnosis, and semi-quantitative tools such as DaTQUANT® and BasGanV2™ provide objective measures. This study compared their diagnostic performance when integrated with supervised machine learning. Methods: We retrospectively analysed 123I-Ioflupane SPECT scans from 169 patients (133 PD, 36 ET). Semi-quantitative analysis was performed using DaTQUANT® v2.0 and BasGanV2™ v.2. Classification tree (ClT), k-nearest neighbour (k-NN), and support vector machine (SVM) models were trained and validated with stratified shuffle split (250 iterations). Diagnostic accuracy was compared between the two software packages. Results: All classifiers reliably distinguished PD from ET. DaTQUANT® consistently achieved higher accuracy than BasGanV2™: 93.8%, 93.2%, and 94.5% for ClT, k-NN, and SVM, respectively, versus 90.9%, 91.7%, and 91.9% for BasGanV2™ (p < 0.001). Sensitivity and specificity were also consistently higher for DaTQUANT® than BasGanV2. Class imbalance (PD > ET) was addressed using Synthetic Minority Over-sampling Technique (SMOTE). Conclusions: Machine learning analysis of 123I-Ioflupane SPECT enhances differentiation between PD and ET. DaTQUANT® outperformed BasGanV2™, suggesting greater suitability for AI-driven decision support. These findings support the integration of semi-quantitative and AI-based approaches into clinical workflows and highlight the need for harmonised methodologies in movement disorder imaging.

PURPOSE:To investigate the effects of radical radiotherapy (RT) relevant interruptions (RRI), single (sRRI) or multiple (mRRI), on Biochemical Failure-Free Survival (BFFS), Metastases-Free Survival (MFS) and Overall Survival (OS) in prostate cancer (PCa) patients. METHODS:We conducted a retrospective analysis involving 383 patients diagnosed with prostate cancer (PCa) who received radical RT between March 2013 and April 2021, with doses ranging from 60 to 80 Gy (median dose 76.0 Gy), either alone or in combination with androgen deprivation therapy. The study aimed to evaluate the effects of sRRI and mRRI radiation-related interruptions on BFFS, MFS, and OS using the Kaplan-Meier method. Additionally, we adjusted for relevant prognostic factors using three multivariate Cox regression proportional hazard models. RESULTS:In the univariate analysis, it was observed that patients who experienced unexpected RRIs (50.1%: 35.5% sRRI and 14.6% mRRI), resulting in a median overall treatment time prolongation of five days, exhibited a higher incidence of biochemical failure (BF) and metastases (Met). However, no difference was observed in OS. In the multivariate analysis, it was found that RRIs were significantly associated with increased hazards of BF (sRRI, aHR: 4.61, 95% CI: 2.80-7.60; mRRIs, aHR: 9.92, 95% CI: 5.61-17.54), Met (sRRI, aHR: 4.20, 95% CI: 1.97-8.94; mRRI, aHR: 7.01, 95% CI: 2.94-6.71), and all-cause mortality (mRRI, aHR: 1.89, 95% CI: 1.18-3.03). CONCLUSIONS:sRRIs were associated with both lower BFFS and MFS, while mRRIs with both BFFS, MFS and OS.

Background: In addition to the typical form resembling the classical Japanese octopus trap, atypical variants of Takotsubo cardiomyopathy (TTC) sparing the left ventricular apex have emerged over the years. The aim of this systematic review is to provide a comprehensive overview of the cardiac nuclear imaging findings in atypical variants. Methods: This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The literature research was carried out online on the Pubmed, Scopus, Central (Cochrane Library), and Web Of Science databases. Results: A total of 14 articles were ultimately selected. Myocardial perfusion scintigraphy was performed in nine studies, followed by 123I-mIBG scintigraphy, 123I-BMIPP scintigraphy, and 18F-FDG PET. In seven cases, a single cardiac nuclear imaging technique was performed, while in the remaining five and two cases, two and three different imaging modalities were, respectively, used. The most common atypical variant of our selection was the midventricular form, followed by reverse/inverted/basal TTC, with only a single case reported of a focal pattern. Conclusions: As the reason why TTC variants occur is still not clear, a deeper understanding of the current knowledge could be the basis for providing more insights into this fascinating disorder and its uncommon manifestations.

Aims Recovery of cardiovascular diagnostic testing in Italy after the coronavirus disease-2019 (COVID-19) pandemic has not been quantified. The study aims to describe cardiac diagnostic procedure volumes, centres practice and protocols, and staff members’ well-being 1 year after COVID-19 outbreak in Italy. Methods and results A global survey was conducted by the International Atomic Energy Agency to evaluate changes in cardiac diagnostic procedure volumes in April 2021. Evaluated procedures were transoesophageal echocardiogram, coronary computed tomography angiography, coronary artery calcium scanning, nuclear medicine infection studies, invasive coronary angiography, rest and stress transthoracic echocardiogram, cardiac magnetic resonance, single-photon emission computed tomography and positron emission tomography, and stress electrocardiogram. Data were compared with April 2020 and March 2019. Forty-two Italian centres took part in the survey. In April 2020, there was a 72% decrease of median volumes of cardiac diagnostic procedures compared with March 2019. In April 2021, volumes of cardiac diagnostic procedures remained decreased by 3% when compared with March 2019. Stress electrocardiogram, coronary computed tomography angiography, and stress cardiac magnetic resonance volumes increased in April 2021 compared with baseline (29%, 6%, and 16%, respectively). The majority of centres had adopted physical distancing measures (93%), COVID-19 screening through questionnaires (76%), or temperature checks (93%). Twenty-five per cent of physicians at Italian responding sites reported excessive levels of psychological stress. Conclusion In April 2021, volumes of cardiac diagnostic procedures at Italian responding sites were still recovering. Centres had implemented several adaptations to ensure the provision of care to their patients. Even 1 year after the pandemic, a substantial minority of Italian healthcare providers were still experiencing excessive psychological stress.

the aim of our study is to collect all the measures adopted in clinical daily practice to reduce the patient dose in the different steps (injected activity, CT protocol, reconstruction methods, etc.) and to explore their advantages and limitations. a comprehensive search of relevant articles was conducted in medical databases (i.e. Embase, Scopus, Web of Science and Medline), using the keywords: dose optimization, computed tomography, PET, radiopharmaceutical, PET/CT, PET/MRI, DRL. Only English and full-text articles were included, without limitations on the year of publication. after the screening, 58 articles were selected that were considered eligible for the analysis. The methods used for dose optimization include: improving reconstruction algorithms; reducing the injected radiotracer activity but increasing the acquisition times, especially in new digital PET scanner; using long-axial field of view (LAFOV) PET/CT tomographs; and modulating CT radiation dose by using artificial intelligence tools. All these approaches are in line with those implemented in our departments. Furthermore, the future trend is prioritizing data collection, in accordance with international guidelines, to better understand PET/CT dose discrepancies while also striving to optimize radiation doses without compromising the quality of PET images. several optimization methods have been developed and implemented to reduce the dose delivered to the patients who undergo PET/CT or PET/MRI examination; in recent years, the advent of digital PET and LAFOV scanners has been an important step in the evolution of molecular imaging and dose optimization and there has also been an increasingly widespread adoption in clinical practice.