18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS.

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

Improving the chances of response to splenectomy in immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by isolated thrombocytopenia. Its pathogenesis is complex relying in large part on destruction of platelets recognized by autoantibodies within the spleen. However, other mechanisms, such as platelet desialylation, may play a role in platelet reduction by accelerating their clearance in the liver. In their study, Mendoza and colleagues reported on platelet scintigraphy performed in 51 ITP patients, showing a response in 87.5% when the sequestration occurred in the spleen versus 45% in case of non-splenic destruction. Platelet desialylation was also measured after splenectomy and found to be higher in non-responder patients. These latter results, while requiring confirmation prior to splenectomy, support platelet desialylation may also be a potential biomarker of non-response to splenectomy. Commentary on: Mendoza et al. Study of platelet kinetics in immune thrombocytopenia to predict splenectomy response. Br J Haematol 2024;204:315-323.

The usefulness of indium-111 platelet scintigraphy beyond predicting efficacy of splenectomy.

There are no clear indicators to predict the outcome of patients with immune thrombocytopenia or the response to drugs. The work of Durand et al. shows that Indium-111 platelet scintigraphy is useful in identifying those patients who will benefit from splenectomy and lays the groundwork for studies demonstrating the increased corticosteroid dependency and rituximab refractoriness of the hepatic platelet sequestration group. Commentary on: Durand et al. Course of immune thrombocytopenia according to the site of platelet destruction identified by indium-111 platelet scintigraphy. Br J Haematol 2024 (Online ahead of print). doi: 10.1111/bjh.19833.

Course of immune thrombocytopenia according to the site of platelet destruction identified by indium-111 platelet scintigraphy.

In primary immune thrombocytopenia (ITP), predictors of disease evolution and treatment response are needed. Data based on the site of platelet destruction are scarce. We performed a retrospective single-centre study of adult patients with primary ITP undergoing at least one Indium-111 platelet scintigraphy (IPS) between 2009 and 2018. Thirty-three patients had isolated hepatic platelet destruction (H-group), and 97 isolated splenic destruction (S-group). Median age at diagnosis (p < 0.001), proportion of associated cardiovascular (p < 0.001), organ-specific autoimmune diseases (p = 0.02), dependence on steroids (p = 0.003) and failure to rituximab (p = 0.01) were higher and relapse more frequent (p = 0.03) in H-group compared to non-splenectomized patients in S-group. Splenectomy was only performed in patients from S-group (as patients with hepatic sequestration are not splenectomized in our centre): 79% were in relapse-free remission at the end of a median 3.4-year post-IPS follow-up, 16% relapsed. In multivariate analyses, only a history of organ-specific autoimmune or inflammatory disease was significantly associated with hepatic sequestration (OR = 4.3, 95% CI = 1.2-15, p = 0.02). Patients with isolated hepatic sequestration were older, had more cardiovascular events and organ-specific autoimmune diseases, greater dependence on steroids, more relapses and a decreased response rate to rituximab suggesting an increased refractoriness to immunomodulatory therapies. Patients with isolated splenic sequestration responded well to splenectomy.

Benefits of Prokinetics, Gastroparesis Diet, or Neuromodulators Alone or in Combination for Symptoms of Gastroparesis.

BACKGROUND & AIMS: Prokinetics have limited effectiveness for treating symptoms of gastroparesis. Thus, alternative or adjunct therapies, such as gastroparesis diets or neuromodulators, are often prescribed. Their therapeutic benefits alone or in combination remain unclear. METHODS: One hundred and twenty-nine patients with symptoms of gastroparesis underwent wireless motility capsule gastric emptying time and gastric emptying scintigraphy. Based on test results, changes in therapy were recommended. Changes in Gastroparesis Cardinal Symptom Index (GCSI) and individual symptom scores over 6 months were related to recommendations for prokinetics, gastroparesis diet, or neuromodulators given as solo new therapies or in dual combinations. Multivariate analyses were performed to adjust for gastric emptying and other variables. RESULTS: In the whole group regardless of therapy, GCSI scores decreased by 0.53 points (interquartile range, -1.25 to 0.05; P < .0001) over 6 months. GCSI did not decrease for prokinetics as solo new therapy (P = .95). Conversely, neuromodulators as solo therapy decreased GCSI scores (P = .04) and all individual symptoms except nausea/vomiting (P = .86). Prokinetics combined with gastroparesis diets or neuromodulators improved GCSI scores (P ≤ .04) and most individual symptoms. Adjusting for gastric emptying time on multivariate analyses showed greater GCSI decreases for nondelayed emptying for neuromodulators as solo new therapy (P = .01). Gastric emptying scintigraphy, gender, diabetes, and functional dyspepsia did not influence responses to any treatment. CONCLUSIONS: Initiating prokinetics as solo new therapy had little benefit for patients with symptoms of gastroparesis. Neuromodulators as the only new therapy decreased symptoms other than nausea and vomiting, especially with nondelayed gastric emptying. Adding gastroparesis diets or neuromodulators to prokinetics offered relief, suggesting that combination therapies may be more useful in managing these patients. (ClinicalTrials.gov NCT02022826.).

[99mTc]Tc-hydroxydiphosphonate uptake in soft tissue is associated with amyloid load in subcutaneous abdominal fat tissue and mortality in wild-type transthyretin amyloidosis patients.

PURPOSE: Bone scintigraphy is key to non-invasively diagnosing wild-type transthyretin (ATTRwt) amyloidosis, and is mainly used to assess cardiac radiotracer uptake. However, extracardiac radiotracer uptake is also observed. We investigated whether intensity of soft tissue radiotracer uptake is associated with amyloid load in subcutaneous abdominal fat tissue and with mortality. METHODS: This prospective cohort study included 94 ATTRwt amyloidosis patients and 26 amyloid-negative heart failure controls who underwent whole-body [99mTc]Tc-hydroxydiphosphonate scintigraphy. Site-to-background ratios were calculated for heart, elbows, subcutaneous tissue, shoulders and wrists on anterior planar bone scintigraphy images using rib and whole-body radiotracer uptake as background. Fat tissue aspirates were stained with Congo red to grade amyloid load. Site-to-rib ratios were compared between ATTRwt amyloidosis patients and controls, and associations of site-to-background ratio with Congo red score and all-cause mortality were studied. RESULTS: ATTRwt amyloidosis patients had higher soft tissue-to-rib, heart-to-rib and heart-to-whole body ratios compared with controls. The intensity of soft tissue uptake was positively associated with amyloid load in fat tissue in ATTRwt amyloidosis patients. Estimated glomerular filtration rate, N-terminal brain natriuretic propeptide, high-sensitivity cardiac troponin T (hs-cTnT), and the prognostic Mayo and NAC staging system were associated with all-cause mortality in univariable models. Soft tissue/rib ratio, hs-cTnT and the prognostic staging systems were the only two variables that were independently associated withall-cause mortality. CONCLUSION: Soft tissue radiotracer uptake on bone scintigraphy in ATTRwt amyloidosis patients is positively associated with amyloid load in abdominal fat tissue and is independently associated with mortality.

Cardiac [99mTc]Tc-hydroxydiphosphonate uptake on bone scintigraphy in patients with hereditary transthyretin amyloidosis: an early follow-up marker?

PURPOSE: There is a need for early quantitative markers of potential treatment response in patients with hereditary transthyretin (ATTRv) amyloidosis to guide therapy. This study aims to evaluate changes in cardiac tracer uptake on bone scintigraphy in ATTRv amyloidosis patients on different treatments. METHODS: In this retrospective cohort study, outcomes of 20 patients treated with the transthyretin (TTR) gene silencer patisiran were compared to 12 patients treated with a TTR-stabilizer. Changes in NYHA class, cardiac biomarkers in serum, wall thickness, and diastolic parameters on echocardiography and NYHA class during treatment were evaluated. RESULTS: Median heart/whole-body (H/WB) ratio on bone scintigraphy decreased from 4.84 [4.00 to 5.31] to 4.16 [3.66 to 4.81] (p < .001) in patients treated with patisiran for 29 [15-34] months. No changes in the other follow-up parameters were observed. In patients treated with a TTR-stabilizer for 24 [20 to 30] months, H/WB ratio increased from 4.46 [3.24 to 5.13] to 4.96 [ 3.39 to 5.80] (p = .010), and troponin T increased from 19.5 [9.3 to 34.0] ng/L to 20.0 [11.8 to 47.8] ng/L (p = .025). All other parameters did not change during treatment with a TTR-stabilizer. CONCLUSION: A change in cardiac tracer uptake on bone scintigraphy may be an early marker of treatment-specific response or disease progression in ATTRv amyloidosis patients.

Ultra-fast whole-body bone tomoscintigraphies achieved with a high-sensitivity 360° CZT camera and a dedicated deep-learning noise reduction algorithm.

This study aimed to determine whether the whole-body bone Single Photon Emission Computed Tomography (SPECT) recording times of around 10 min, routinely provided by a high-sensitivity 360° cadmium and zinc telluride (CZT) camera, can be further reduced by a deep-learning noise reduction (DLNR) algorithm. METHODS: DLNR was applied on whole-body images recorded after the injection of 545 ± 33 MBq of [99mTc]Tc-HDP in 19 patients (14 with bone metastasis) and reconstructed with 100%, 90%, 80%, 70%, 60%, 50%, 40%, and 30% of the original SPECT recording times. RESULTS: Irrespective of recording time, DLNR enhanced the contrast-to-noise ratios and slightly decreased the standardized uptake values of bone lesions. Except in one markedly obese patient, the quality of DLNR processed images remained good-to-excellent down to 60% of the recording time, corresponding to around 6 min SPECT-recording. CONCLUSION: Ultra-fast SPECT recordings of 6 min can be achieved when DLNR is applied on whole-body bone 360° CZT-SPECT.

Diagnostic performance of molecular imaging methods in predicting the progression from mild cognitive impairment to dementia: an updated systematic review.

PURPOSE: Epidemiological and logistical reasons are slowing the clinical validation of the molecular imaging biomarkers in the initial stages of neurocognitive disorders. We provide an updated systematic review of the recent advances (2017-2022), highlighting methodological shortcomings. METHODS: Studies reporting the diagnostic accuracy values of the molecular imaging techniques (i.e., amyloid-, tau-, [18F]FDG-PETs, DaT-SPECT, and cardiac [123I]-MIBG scintigraphy) in predicting progression from mild cognitive impairment (MCI) to dementia were selected according to the Preferred Reporting Items for a Systematic Review and Meta-Analysis (PRISMA) method and evaluated with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Main eligibility criteria were as follows: (1) ≥ 50 subjects with MCI, (2) follow-up ≥ 3 years, (3) gold standard: progression to dementia or diagnosis on pathology, and (4) measures of prospective accuracy. RESULTS: Sensitivity (SE) and specificity (SP) in predicting progression to dementia, mainly to Alzheimer's dementia were 43-100% and 63-94% for [18F]FDG-PET and 64-94% and 48-93% for amyloid-PET. Longitudinal studies were lacking for less common disorders (Dementia with Lewy bodies-DLB and Frontotemporal lobe degeneration-FTLD) and for tau-PET, DaT-SPECT, and [123I]-MIBG scintigraphy. Therefore, the accuracy values from cross-sectional studies in a smaller sample of subjects (n > 20, also including mild dementia stage) were chosen as surrogate outcomes. DaT-SPECT showed 47-100% SE and 71-100% SP in differentiating Lewy body disease (LBD) from non-LBD conditions; tau-PET: 88% SE and 100% SP in differentiating DLB from Posterior Cortical Atrophy. [123I]-MIBG scintigraphy differentiated LBD from non-LBD conditions with 47-100% SE and 71-100% SP. CONCLUSION: Molecular imaging has a moderate-to-good accuracy in predicting the progression of MCI to Alzheimer's dementia. Longitudinal studies are sparse in non-AD conditions, requiring additional efforts in these settings.

EANM position paper on challenges and opportunities of full-ring 360° CZT bone imaging: it's time to let go of planar whole-body bone imaging.

The introduction of smaller footprint, more sensitive Cadmium-Zinc-Telluride (CZT)-based detectors with improved spatial and energy resolution has enabled the design of innovative full-ring 360° CZT SPECT/CT systems (e.g., VERITON® and StarGuide™). With this transformative technology now aiming to become mainstream in clinical practice, several critical questions need to be addressed. This EANM position paper provides practical recommendations on how to use these devices for routine bone SPECT/CT studies, facilitating the transition from traditional planar whole-body imaging and conventional SPECT/CT to these novel systems. In particular, initial guidance is provided on imaging acquisition and reporting workflows, image reconstruction, and CT acquisition parameters. Given the emerging nature of this technology, the available evidence base is still limited, and the proposed adaptations in workflows and scan protocols will likely evolve before being integrated into definitive guidelines. In the meantime, this EANM position paper serves as a comprehensive guide for integrating these advanced hybrid SPECT/CT imaging systems into clinical practice and outlining areas for further study.

Diagnostic performance of liver stiffness as marker of liver involvement in systemic immunoglobulin light chain (AL) amyloidosis.

OBJECTIVE: To investigate the diagnostic performance of liver stiffness for detecting liver involvement in immunoglobulin light chain (AL) amyloidosis. METHODS: Liver stiffness was measured using transient elastography in 71 patients with systemic AL amyloidosis and 18 patients with wild type transthyretin (ATTRwt) amyloidosis with cardiomyopathy. Both non-invasive consensus criteria and serum amyloid P component (SAP) scintigraphy were used as substitute standards instead of liver biopsy for establishing liver involvement. RESULTS: Liver stiffness was higher in AL amyloidosis patients with liver involvement than in those without: this was observed using both consensus criteria (median 14.4 kPa vs. 8.1 kPa; p = 0.001) and SAP scintigraphy (median 20.9 kPa vs. 6.2 kPa; p < 0.001). Liver stiffness was also higher in AL amyloidosis patients with liver involvement compared to AL and ATTRwt amyloidosis patients with cardiac involvement. Based on receiver operating characteristic (ROC) curves a cut-off value of 14.4 kPa for stiffness was optimal to indicate liver involvement, providing sensitivity and specificity of 50% and 74%, respectively, using the consensus criteria and 63% and 90%, respectively, using SAP scintigraphy as standard. CONCLUSION: Liver stiffness is a promising tool to establish liver involvement in AL amyloidosis having potential to become part of updated criteria for liver involvement.

Concordance between vessel-specific and vascular territory coronary functional assessment: A comparison of quantitative flow ratio and myocardial perfusion scintigraphy.

BACKGROUND: Quantitative flow ratio (QFR) and myocardial perfusion scintigraphy (MPS) are utilized for assessing coronary artery disease (CAD) significance. We aimed to analyze their concordance and prognostic impact. AIMS: We aimed to analyze the concordance between QFR and MPS and their risk stratification. METHODS: Patients with invasive coronary angiography and MPS were categorized as concordant if QFR ≤ 0.80 and summed difference score (SDS) ≥ 4 or if QFR > 0.80 and SDS < 4; otherwise, they were discordant. Concordance was classified by coronary territory involvement: total (three territories), partial (two territories), poor (one territory), and total discordance (zero territories). Leaman score assessed coronary atherosclerotic burden. RESULTS: 2010 coronary territories (670 patients) underwent joint QFR and MPS analysis. MPS area under the curve for QFR ≤ 0.80 was 0.637. Concordance rates were total (52.5%), partial (29.1%), poor (15.8%), and total discordance (2.6%). Most concordance occurred in patients without significant CAD or with single-vessel disease (89.5%), particularly without MPS perfusion defects (91.5%). Leaman score (odds ratio [OR]: 0.839, 95% confidence interval [CI]: 0.805-0.875, p < 0.001) and MPS perfusion defect (summed stress score [SSS] ≥ 4) (OR: 0.355, 95% CI: 0.211-0.596, p < 0.001) were independent predictors for discordance. After 1400 days, no significant difference in death/myocardial infarction was observed based on MPS assessment, but Leaman score, functional Leaman score, and average QFR identified higher risk patients. CONCLUSIONS: MPS showed good overall accuracy in assessing QFR significance but substantial discordance existed. Predictors for discordance included higher atherosclerotic burden and MPS perfusion defects (SSS ≥ 4). Leaman score, QFR-based functional Leaman score, and average QFR provided better risk stratification for all-cause death and myocardial infarction than MPS.

Can CT or MRI volumetry substitute scintigraphy in living kidney donor evaluation? A systematic review.

BACKGROUND: Current potential living kidney donor's assessment includes functional and anatomical evaluation. Scintigraphy is recommended in some cases and some centers include this test in the donor's protocol. Recent studies advocate for the avoidance of this test as CT or MRI volumetry showed to accurately assess donor's renal function. OBJECTIVE: To summarize scientific evidence on image tests for pre-donation and/or post-nephrectomy renal function evaluation. EVIDENCE ACQUISITION: This review followed the guidelines set by the European Association of Urology and adhered to PRISMA 2020 recommendations. The protocol was registered in PROSPERO on 10th December 2022 (ID: CRD42022379273). EVIDENCE SYNTHESIS: Twenty-one studies met the inclusion criteria after thorough screening and eligibility assessment. According to QUADAS-2, patient selection and flow/timing domains showed a predominant low risk of bias. The correlation between split renal function (SRF) using CT and scintigraphy varied from weak (r = 0.21) to remarkably strong (r = 0.949). Bland-Altman agreement demonstrated moderate to excellent results, with mean differences ranging from -0.06% to 1.76%. The correlation between split renal volume (CT) and estimated glomerular filtration rate (eGFR) at 6 months or 1 year after nephrectomy showed a moderate correlation, with coefficients ranging from 0.708 to 0.83. The correlation between SRF (MRI) and renal scintigraphy reported a moderate correlation, with correlation coefficients of 0.58 and 0.84. MRI and scintigraphy displayed a good agreement, with a 66% agreement observed and mean differences of ± 0.3%. CONCLUSIONS: Despite study heterogeneity, MRI or CT-based renal volumetry appears promising compared to scintigraphy, with favorable correlations and agreement.

Comparison between CT volumetry, technetium99m galactosyl-serum-albumin scintigraphy, and gadoxetic-acid-enhanced MRI to estimate the liver fibrosis stage in preoperative patients.

OBJECTIVES: To compare the efficacy of computed tomography volumetry (CTV), technetium99m galactosyl-serum-albumin (99mTc-GSA) scintigraphy, and gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid-enhanced MRI (EOB-MRI) in estimating the liver fibrosis (LF) stage in patients undergoing liver resection. METHODS: This retrospective study included 91 consecutive patients who had undergone preoperative dynamic CT and 99mTc-GSA scintigraphy. EOB-MRI was performed in 76 patients. CTV was used to measure the total liver volume (TLV), spleen volume (SV), normalised to the body surface area (BSA), and liver-to-spleen volume ratio (TLV/SV). 99mTc-GSA scintigraphy provided LHL15, HH15, and GSA indices. The liver-to-spleen ratio (LSR) was calculated in the hepatobiliary phase of EOB-MRI. Hyaluronic acid and type 4 collagen levels were measured in 65 patients. Logistic regression and receiver operating characteristic (ROC) analyses were performed to identify useful parameters for estimating the LF stage and laboratory data. RESULTS: According to the multivariable logistic regression analysis, SV/BSA (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.003-1.02; p = 0.011), LSR (OR, 0.06; 95%CI, 0.004-0.70; p = 0.026), and hyaluronic acid (OR, 1.01; 95%CI, 1.001-1.02; p = 0.024) were independent variables for severe LF (F3-4). Combined SV/BSA, LSR, and hyaluronic acid correctly estimated severe LF, with an AUC of 0.91, which was significantly larger than the AUCs of the GSA index (AUC = 0.84), SV/BSA (AUC = 0.83), or LSR (AUC = 0.75) alone. CONCLUSIONS: Combined CTV, EOB-MRI, and hyaluronic acid analyses improved the estimation accuracy of severe LF compared to CTV, EOB-MRI, or 99mTc-GSA scintigraphy individually. CLINICAL RELEVANCE STATEMENT: The combined analysis of spleen volume on CT volumetry, liver-to-spleen ratio on gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid-enhanced MRI, and hyaluronic acid can identify severe liver fibrosis associated with a high risk of liver failure after hepatectomy and recurrence in patients with hepatocellular carcinoma. KEY POINTS: • Spleen volume of CT volumetry normalised to the body surface area, liver-to-spleen ratio of EOB-MRI, and hyaluronic acid were independent variables for liver fibrosis. • CT volumetry and EOB-MRI enable the detection of severe liver fibrosis, which may correlate with post-hepatectomy liver failure and complications. • Combined CT volumetry, gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid-enhanced MRI (EOB-MRI), and hyaluronic acid analyses improved the estimation of severe liver fibrosis compared to technetium99m galactosyl-serum-albumin scintigraphy.

Urodynamic study and its correlation with cardiac meta-iodobenzylguanidine (MIBG) in body-first and brain-first subtypes of Parkinson's disease.

BACKGROUND AND PURPOSE: Lower urinary tract symptoms (LUTS) are frequently observed in patients with Parkinson's disease (PD), but the underlying mechanism remains elusive. The concept of "body-first" and "brain-first" subtypes in PD has been proposed, but the correlation of PD subtype with LUTS remains unclear. We aimed to investigate the disparities in urological dysfunctions between body-first and brain-first subtypes of PD using urodynamic studies (UDS). METHODS: We reviewed patients with PD (disease duration <3 years) who had undergone UDS and completed urological questionnaires (Overactive Bladder Symptom Score [OABSS] and International Prostate Symptom Score [IPSS]) and a voiding diary. Patients were categorized as having body-first or brain-first PD based on cardiac sympathetic denervation (CSD) using cardiac meta-iodobenzylguanidine (MIBG) uptake and the presence of rapid eye movement sleep behavior disorder (RBD), assessed using a questionnaire (PD with CSD and RBD indicating the body-first subtype). RESULTS: A total of 55 patients with PD were categorized into body-first PD (n = 37) and brain-first PD (n = 18) groups. The body-first PD group exhibited smaller voiding volume and first desire volume (FDV) than the brain-first PD group (p < 0.05 in both). Also, the body-first PD group had higher OABSS and IPSS scores, and higher prevalence of overactive bladder diagnosed by OABSS, compared to the brain-first PD group. In multiple linear regression, cardiac MIBG uptake was positively correlated with FDV and voiding volume and negatively correlated with OABSS and IPSS (p < 0.05 in all). CONCLUSIONS: Patients with the body-first PD subtype exhibited more pronounced overactive bladder symptoms and impaired storage function in the early stage of disease. Additionally, cardiac MIBG was significantly associated with urological dysfunction.

Are 99mTC-Sestamibi Single Photon Emission Computed Tomography Scan Results Associated to the Parathyroid Cell Type in Primary Hyperparathyroidism?

INTRODUCTION: 99mTC-sestamibi scintigraphy (SPECT-CT) is a common imaging modality for parathyroid localization in primary hyperparathyroidism (PHPT). Prior studies have suggested that the cellular composition of parathyroid adenomas influences SPECT-CT imaging results. Other biochemical and anatomical factors may also play a role in false negative results. Therefore, after controlling for confounding variables, we sought to determine whether the histologic composition of parathyroid adenomas is associated to SPECT-CT results in patients with single gland disease causing PHPT. METHODS: A retrospective review of patients with PHPT due to confirmed single gland disease was performed over a 2-y period. A 1:1 propensity score matching was done between patients with positive and negative SPECT-CT results with regard to demographical, biochemical, and anatomical characteristics followed by blinded pathologic examination of cell composition in the matched pairs. RESULTS: Five hundred forty two patients underwent routine four gland exploration and 287 (53%) patients were found to have a single adenoma. Of those, 26% had a negative SPECT-CT result. There were significant differences between groups with regards to biochemical profile, gland location, and gland size. All of which became nonsignificant after propensity score matching. Adenomas were primarily composed of chief cells, with no difference between groups (95% versus 97%, P = 0.30). In the positive SPECT-CT group, chief cells were the dominant cell type in 68% of the cases, followed by mixed type (13%), oxyphil cells (12%), and clear cells (7%). This was similar to the negative SPECT-CT group (P = 0.22). CONCLUSIONS: While certain patient's clinical characteristics are associated with SPECT-CT imaging results, histologic cell type is not significantly associated.

18F-FDG PET/CT and radiolabeled leukocyte SPECT/CT imaging for the evaluation of cardiovascular infection in the multimodality context: ASNC Imaging Indications (ASNC I2) Series Expert Consensus Recommendations from ASNC, AATS, ACC, AHA, ASE, EANM, HRS, IDSA, SCCT, SNMMI, and STS.

This document on cardiovascular infection, including infective endocarditis, is the first in the American Society of Nuclear Cardiology Imaging Indications (ASNC I2) series to assess the role of radionuclide imaging in the multimodality context for the evaluation of complex systemic diseases with multi-societal involvement including pertinent disciplines. A rigorous modified Delphi approach was used to determine consensus clinical indications, diagnostic criteria, and an algorithmic approach to diagnosis of cardiovascular infection including infective endocarditis. Cardiovascular infection incidence is increasing and is associated with high morbidity and mortality. Current strategies based on clinical criteria and an initial echocardiographic imaging approach are effective but often insufficient in complicated cardiovascular infection. Radionuclide imaging with 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (CT) and single photon emission computed tomography/CT leukocyte scintigraphy can enhance the evaluation of suspected cardiovascular infection by increasing diagnostic accuracy, identifying extracardiac involvement, and assessing cardiac implanted device pockets, leads, and all portions of ventricular assist devices. This advanced imaging can aid in key medical and surgical considerations. Consensus diagnostic features include focal/multi-focal or diffuse heterogenous intense 18F-FDG uptake on valvular and prosthetic material, perivalvular areas, device pockets and leads, and ventricular assist device hardware persisting on non-attenuation corrected images. There are numerous clinical indications with a larger role in prosthetic valves, and cardiac devices particularly with possible infective endocarditis or in the setting of prior equivocal or non-diagnostic imaging. Illustrative cases incorporating these consensus recommendations provide additional clarification. Future research is necessary to refine application of these advanced imaging tools for surgical planning, to identify treatment response, and more.

When surgical option is not provided: a successful multidisciplinary approach to a refractory case of sternal osteomyelitis following coronary surgery.

PURPOSE: Sternal osteomyelitis is a major complication of cardiac operations performed through median sternotomy. The surgical treatment, which involves the debridement and removal of whole infected and necrotic tissue is the standard of care, although it is sometimes unachievable. This may occur, for instance, when the infectious-inflammatory process invades the anterior mediastinum and tenaciously incorporates one or more of vital anatomical structures. METHODS AND RESULTS: An inoperable case of postoperative sternal osteomyelitis that involved the right ventricle and the right coronary artery, and that was successfully treated using a nonsurgical multidisciplinary approach, is reported here. CONCLUSION: For highly selected patients with sternal osteomyelitis for whom surgery is a too risky option, an approach including the contribution of various specialists might be a viable way out.

Comparison between whole-body magnetic resonance imaging and whole-body metaiodobenzylguanidine scintigraphy in the evaluation of primary tumor and metastases in neuroblastoma.

BACKGROUND: Whole-body metaiodobenzylguanidine (131 I-MIBG) scintigraphy is the gold standard method to detect neuroblastoma; however, it depends on radioactive material and is expensive. In contrast, whole-body magnetic resonance imaging (WB-MRI) is affordable in developing countries and has been shown to be effective in the evaluation of solid tumors. This study aimed to compare the sensitivity and specificity of WB-MRI with MIBG in the detection of primary tumors and neuroblastoma metastases. PROCEDURE: This retrospective study enrolled patients with neuroblastoma between 2013 and 2020. All patients underwent WB-MRI and MIBG at intervals of up to 15 days. The results were marked in a table that discriminated anatomical regions for each patient. Two experts evaluated, independently and in anonymity, the WB-MRI images, and two others evaluated MIBG. The results were compared in terms of sensitivity and specificity, for each patient, considering MIBG as the gold standard. This study was approved by the UNIFESP Ethics Committee. RESULTS: Thirty patients with neuroblastoma were enrolled in this study. The age ranged from 1 to 15 years, with a mean of 5.7 years. The interval between exams (WB-MRI and MIBG) ranged from 1 to 13 days, with an average of 6.67 days. Compared to MIBG, WB-MRI presented a sensitivity and specificity greater than or equal to 90% for the detection of primary neuroblastoma in bones and lymph nodes. When we consider the patient without individualizing the anatomical regions, WB-MRI presented sensitivity of 90% and specificity of 73.33%. CONCLUSION: In conclusion, WB-MRI is a sensitive and specific method to detect neuroblastoma in bone and lymph nodes and highly sensible to primary tumor diagnosis, suggesting that this test is a viable alternative in places where MIBG is difficult to access. Studies with a larger number of cases are necessary for definitive conclusions.

Emerging Role of Scintigraphy Using Bone-Seeking Tracers for Diagnosis of Cardiac Amyloidosis: AJR Expert Panel Narrative Review.

Amyloidoses are a complex group of clinical diseases that result from progressive organ dysfunction due to extracellular protein misfolding and deposition. The two most common types of cardiac amyloidosis are transthyretin amyloidosis (ATTR) and light-chain (AL) amyloidosis. Diagnosis of ATTR cardiomyopathy (ATTR-CM) is challenging owing to its phenotypic similarity to other more common cardiac conditions, the perceived rarity of the disease, and unfamiliarity with its diagnostic algorithms; endomyocardial biopsy was historically required for diagnosis. However, myocardial scintigraphy using bone-seeking tracers has shown high accuracy for detection of ATTR-CM and has become a key noninvasive diagnostic test for the condition, receiving support from professional society guidelines and transforming prior diagnostic paradigms. This AJR Expert Panel Narrative Review describes the role of myocardial scintigraphy using bone-seeking tracers in the diagnosis of ATTR-CM. The article summarizes available tracers, acquisition techniques, interpretation and reporting considerations, diagnostic pitfalls, and gaps in the current literature. The critical need for monoclonal testing of patients with positive scintigraphy results to differentiate ATTR-CM from AL cardiac amyloidosis is highlighted. Recent updates in guideline recommendations that emphasize the importance of a qualitative visual assessment are also discussed.