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Purpose: To evaluate the prognostic value of the quantitative assessment of 99mTc-methylene diphosphonate (99mTc-MDP) bone SPECT/CT in castration-resistant prostate cancer (CRPC) patients with bone metastases. Methods: A total of 103 patients who underwent 99mTc-MDP bone SPECT/CT imaging from the neck to the proximal femur were included. First, in 65 patients without bone metastases, the normal range of standardized uptake value (SUV) of non-pathological bone was evaluated to determine an SUV threshold to reliably exclude most normal osseous activity. Then, in 38 CRPC patients with bone metastases, lesion uptake volume (LUV), which is the extracted volume of bone metastases exhibiting high accumulation above the SUV threshold, was calculated. The relation between LUV and prostate-related mortality was statistically evaluated. Results: Based on the SUV measurements of non-pathological bones, the optimal SUV threshold, which defines abnormal bone SPECT uptake, was determined to be 8. Median LUV was 39 mL (interquartile range 4.0–104.3 mL) in the CRPC subjects with bone metastases. Kaplan–Meier survival analysis showed a significant relation between prostate cancer-specific survival and LUV (cut-off value, 19.95 mL; P = 0.001). Multivariate analysis revealed LUV as an independent prognostic factor for the survival (P = 0.008, hazard ratio 23.424). Global chi-square test showed that LUV had significant incremental prognostic value in addition to prostate-specific antigen and the interval from progression to CRPC until bone SPECT/CT (P = 0.022). Conclusion: Quantitative assessment of 99mTc-MDP bone SPECT images can provide valuable prognostic information in CRPC patients with bone metastases. [ABSTRACT FROM AUTHOR]

Abstract Background Atrial fibrillation (AF) is a strong risk factor for Alzheimer’s disease (AD) independent of ischemic stroke. However, the clinicopathological impact of AF on the severity of AD has not been well elucidated. We aimed to investigate the clinical differences between dementia patients with AF and those without AF by means of imaging data. Methods Following approval from the institutional ethics committee, patients with newly diagnosed AD or amnestic mild cognitive impairment (aMCI) were retrospectively screened (n = 170, 79.5 ± 7.4 years old). Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Based on the MRI data, the cerebral volume, cerebral microbleeds (CMBs), periventricular white matter lesions (WMLs), and deep WMLs were evaluated. The regional cerebral blood flow (rCBF) was measured using 123I-IMP SPECT. Results Of the patients, 14 (8.2%) and 156 (91.8%) had AF (AF group) and sinus rhythm (SR group), respectively. The AF group had significantly lower MMSE scores than the SR group (average [standard deviation (SD)]: 19.4 [4.4] and 22.0 [4.4], respectively; p = 0.0347). Cerebral volume and CMBs did not differ between the two groups. The periventricular WMLs, but not the deep WMLs, were significantly larger in the AF group than in the SR group (mean [SD] mL: 6.85 [3.78] and 4.37 [3.21], respectively; p = 0.0070). However, there was no significant difference in rCBF in the areas related to AD pathology between the two groups. Conclusion AD and aMCI patients with AF showed worse cognitive decline along with larger periventricular WMLs compared to those with SR, although the reduction of rCBF was not different between patients with AF and SR. The white matter lesions may be a more important pathology than the impairment of cerebral blood flow in dementia patients with AF. A larger study is needed to confirm our findings in the future.

Background: Cadmium-zinc-telluride (CZT)-based detectors exhibit higher diagnostic sensitivity in myocardial perfusion imaging (MPI) than conventional Anger-MPI for detection of coronary artery disease (CAD); however, reduced specificity and diagnostic accuracy of CZT-MPI were observed. This study aims to compare these different camera systems and to examine the degree of inter-rater reproducibility among readers with varying experience in MPI. Methods: 83 patients who underwent double stress/rest examinations using both a CZT and conventional SPECT cameras within one visit were included. Anonymized and randomized MPI-images were distributed to 15 international readers using a standardized questionnaire. Subsequent coronary angiography findings of ten patients served as a reference for analysis of sensitivity and specificity. Results: Image quality was significantly better in CZT-MPI with significantly lower breast attenuation (P < 0.05). CZT-MPI exhibited higher sensitivity than Anger-MPI (87.5% vs. 62.5%) and significantly reduced specificity (40% vs. 100%). Readers experienced with both camera systems had the highest inter-rater agreement indicating higher reproducibility (CZT 0.54 vs. conv. 0.49, P < 0.05). Conclusions: Higher diagnostic sensitivity of CZT-MPI offers advantages in detection of CAD yet potentially of at the cost of reduced specificity, therefore it requires special training and a differentiated evaluation approach, especially for non-experienced readers with such camera systems. [ABSTRACT FROM AUTHOR]

Nanoparticles are ultrafine particulate matter having considerable potential for treatment of central nervous system (CNS) disorders. Despite their tiny size, the blood-brain barrier (BBB) restricts their access to the CNS. Their direct cerebrospinal fluid (CSF) administration bypasses the BBB endothelium, but still fails to give adequate brain uptake. We present a novel approach for efficient CNS delivery of 111 In-radiolabelled gold nanoparticles (AuNPs; 10–15 nm) via intra- cisterna magna administration, with tracking by SPECT imaging. To accelerate CSF brain influx, we administered AuNPs intracisternally in conjunction with systemic hypertonic saline, which dramatically increased the parenchymal AuNP uptake, especially in deep brain regions. AuNPs entered the CNS along periarterial spaces as visualized by MRI of gadolinium-labelled AuNPs and were cleared from brain within 24 h and excreted through the kidneys. Thus, the glymphatic-assisted perivascular network augment by systemic hypertonic saline is a pathway for highly efficient brain-wide distribution of small AuNPs. [Display omitted] • Brain access of intrathecally administered nanoparticles has been considered sparse. • Glymphatic-assisted CNS drug delivery has emerged as a new CNS drug delivery system. • We studied the brain distribution of 111In-labelled small gold nanoparticles (AuNPs). • Systemic hypertonic solution markedly increased brainwide AuNP delivery. • MRI of Gd-AuNPs visualizes their periarterial flow towards deep brain structures. [ABSTRACT FROM AUTHOR]

Introduction and purpose: To briefly introduce the reader to the application of nuclear medicine studies in the diagnosis and treatment of musculoskeletal disorders developed among athletes. Materials and methods: To prepare this review, publications indexed in the PubMed and Google Scholar databases were analyzed. Special attention was given to full-text articles published in English between 2015 and 2023, as well as to the references cited by the authors of selected publications. Description of the state of knowledge: Nuclear medicine is applied in the diagnosis and therapy of orthopedic conditions. Commonly used nuclear medicine techniques include planar bone scintigraphy (WBS), single-photon emission computed tomography (SPECT) combined with computed tomography (CT), and positron emission tomography (PET) combined with computed tomography (CT). Summary: The utilization of nuclear medicine techniques allows for proper diagnosis and early treatment of musculoskeletal disorders, including pathologies resulting from sports-related physical activity.

Vasospastic angina (VSA), or variant angina, is an under-recognized cause of chest pain and myocardial infarction, especially in Western countries. VSA leads to a declined quality of life and is associated with increased morbidity and mortality. Currently, the diagnosis of VSA relies on invasive testing that requires the direct intracoronary administration of ergonovine or acetylcholine. However, invasive vasoreactivity testing is underutilized. Several non-invasive imaging alternatives have been proposed to screen for VSA. This review aims to discuss the strengths and limitations of available non-invasive imaging tests for vasospastic angina. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) is a strong risk factor for Alzheimer's disease (AD) independent of ischemic stroke. However, the clinicopathological impact of AF on the severity of AD has not been well elucidated. We aimed to investigate the clinical differences between dementia patients with AF and those without AF by means of imaging data. Methods: Following approval from the institutional ethics committee, patients with newly diagnosed AD or amnestic mild cognitive impairment (aMCI) were retrospectively screened (n = 170, 79.5 ± 7.4 years old). Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Based on the MRI data, the cerebral volume, cerebral microbleeds (CMBs), periventricular white matter lesions (WMLs), and deep WMLs were evaluated. The regional cerebral blood flow (rCBF) was measured using 123I-IMP SPECT. Results: Of the patients, 14 (8.2%) and 156 (91.8%) had AF (AF group) and sinus rhythm (SR group), respectively. The AF group had significantly lower MMSE scores than the SR group (average [standard deviation (SD)]: 19.4 [4.4] and 22.0 [4.4], respectively; p = 0.0347). Cerebral volume and CMBs did not differ between the two groups. The periventricular WMLs, but not the deep WMLs, were significantly larger in the AF group than in the SR group (mean [SD] mL: 6.85 [3.78] and 4.37 [3.21], respectively; p = 0.0070). However, there was no significant difference in rCBF in the areas related to AD pathology between the two groups. Conclusion: AD and aMCI patients with AF showed worse cognitive decline along with larger periventricular WMLs compared to those with SR, although the reduction of rCBF was not different between patients with AF and SR. The white matter lesions may be a more important pathology than the impairment of cerebral blood flow in dementia patients with AF. A larger study is needed to confirm our findings in the future. [ABSTRACT FROM AUTHOR]

Introduction: Major depressive disorder (MDD) is a prevalent condition which has a well-known association with ischemic cardiomyopathy, probably explained by an inflammatory mediator mechanism. Statins, besides reducing cholesterol production, have pleiotropic effects including anti-inflammatory activity. The goal was to evaluate the effect of statins as an addition to standard therapy on mood status, brain perfusion, and neurocognitive performance in MDD. Methods: We studied 20 MDD patients with brain single-photon emission tomography and Cambridge Neuropsychological Test Automated Battery (CANTAB), half randomized to 10 mg of Rosuvastatin or placebo, in addition to selective serotonin reuptake inhibitors (SSRIs) therapy and being reevaluated 3 months later. The images were compared using Statistical Parametric Mapping; clinical scores (Hamilton Depression Score with 17 items and Beck's Depression Inventory) as well as neurocognitive parameters were applied as covariances (CoV) to estimate regional cerebral blood flow (rCBF) changes with both therapies. Results: Clinical scores decreased in both groups (p = 0.0001); Beck's presented a larger decrease with statins. We observed significantly rCBF changes expressed as significant larger clusters of voxels (p < 0.05) in the pre/subgenual anterior cingulate plus orbitofrontal cortex and a small area in the posterior cingulate gyrus in the statins group, whereas it was not observed with placebo, when using clinical scores as CoV. A similar pattern of rCBF changes was present with emotions recognition, attentional, paired associates learning, spatial planning, and working memory tasks. Conclusion: Short-term use of low-dose statins in MDD patients under SSRIs results in important rCBF changes in key mood associated areas to improvement in neurocognitive performance. These findings, even though demonstrated in a small sample, could open a new therapeutic tool in the comprehensive management of this disorder. [ABSTRACT FROM AUTHOR]

Dopamine is a neurotransmitter that plays a crucial role in adaptive behavior. A wealth of studies suggests obesity-related alterations in the central dopamine system. The most direct evidence for such differences in humans comes from molecular neuroimaging studies using positron emission tomography (PET) and single-photon emission computed tomography (SPECT). The aim of the current review is to give a comprehensive overview of molecular neuroimaging studies that investigated the relation between BMI or weight status and any dopamine target in the striatal and midbrain regions of the human brain. A structured literature search was performed and a summary of the extracted findings are presented for each of the four available domains: (1) D2/D3 receptors, (2) dopamine release, (3) dopamine synthesis, and (4) dopamine transporters. Recent proposals of a nonlinear relationship between severity of obesity and dopamine imbalances are described while integrating findings within and across domains, after which limitations of the review are discussed. We conclude that despite many observed associations between obesity and substrates of the dopamine system in humans, it is unlikely that obesity can be traced back to a single dopaminergic cause or consequence. For effective personalized prevention and treatment of obesity, it will be crucial to identify possible dopamine (and non-dopamine) profiles and their functional characteristics. [ABSTRACT FROM AUTHOR]

Background: N-isopropyl- (123I) p-iodoamphetamine (123I-IMP) is specifically accumulated in primary central nervous system lymphoma (PCNSL) during single-photon emission tomography (SPECT) and contributes to its diagnostic imaging. However, whether 123I-IMP is accumulated in ocular adnexal lymphoma (OAL), one of the malignant intraorbital tumors, remains unclear. This study aimed to evaluate the diagnostic value of 123I-IMP SPECT in OAL. Methods: Between August 2005 and June 2020, 26 patients with intraorbital tumors underwent neurosurgery at the tertiary care center. Of these, 15 patients who underwent 123I-IMPSPECT before surgery were retrospectively examined. The region of interest was set in the cerebellum ipsilateral to the intraorbital tumor on 123I-IMP SPECT, and the tumor-to-cerebellum ratio (T/C ratio) was calculated using the following formula: T/C ratio = [accumulation of tumor (count/pixel)]/[accumulation of ipsilateral normal cerebellar hemisphere (count/pixel)]. Results: Six patients were included in the OAL group, who were pathologically diagnosed with extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), diffuse large B-cell lymphoma (DLBCL), and plasmacytoma. The T/C ratio in the OAL group was statistically higher than that in the non-OAL group (p < 0.01). The optimal cutoff values for both groups were between 0.76 and < 0.93. The sensitivity and specificity were 1.00, respectively. Conclusions: 123I-IMP SPECT is useful as one of the examinations in the differential diagnoses of OAL, because it showed a significantly higher accumulation in OAL group than in non-OAL group. [ABSTRACT FROM AUTHOR]

Dopamine is a neurotransmitter that plays a crucial role in adaptive behavior. A wealth of studies suggests obesity-related alterations in the central dopamine system. The most direct evidence for such differences in humans comes from molecular neuroimaging studies using positron emission tomography (PET) and single-photon emission computed tomography (SPECT). The aim of the current review is to give a comprehensive overview of molecular neuroimaging studies that investigated the relation between BMI or weight status and any dopamine target in the striatal and midbrain regions of the human brain. A structured literature search was performed and a summary of the extracted findings are presented for each of the four available domains: (1) D2/D3 receptors, (2) dopamine release, (3) dopamine synthesis, and (4) dopamine transporters. Recent proposals of a nonlinear relationship between severity of obesity and dopamine imbalances are described while integrating findings within and across domains, after which limitations of the review are discussed. We conclude that despite many observed associations between obesity and substrates of the dopamine system in humans, it is unlikely that obesity can be traced back to a single dopaminergic cause or consequence. For effective personalized prevention and treatment of obesity, it will be crucial to identify possible dopamine (and non-dopamine) profiles and their functional characteristics.

This review describes the development of single‐photon emission tomography (SPECT) in the Copenhagen area under the leadership of the internationally renown scientist, Niels A. Lassen, and the history leading up to construction of the tomograph. Measurements of global cerebral blood flow (CBF) in the 1940s and 1950s were performed by Kety & Schmidt and Lassen & Munck. Determination of regional cerebral blood flow (rCBF) by intra‐arterial injection of 133Xe and measurement with a 254‐multicrystal scintillation detector and a computer system was a major step forward in the study of physiology and pathophysiology of cortical cerebral blood flow. Tomography with radioisotope ligands, including non‐invasive administration, was advanced in different centres during the 1970s. An emission tomograph, the Tomomatic 64, was developed as a result of a multidisciplinary Danish and international collaboration. It was the first emission tomograph to provide dynamic data that could produce cross‐sectional rCBF images. The present description of the construction and function of the Tomomatic 64 includes comparison with other contemporary and later brain‐dedicated SPECT systems. Basic and clinical application of the Tomomatic 64 in Copenhagen resulted in several hundred important scientific publications and improved diagnostics for patients with a variety of neurological disorders. It is concluded that the development of the Tomomatic 64 was a major step forward in the study and examination of rCBF and brain function related to several brain disorders, in addition to vascular diseases. [ABSTRACT FROM AUTHOR]

In 2023, cardiovascular imaging has made significant advancements, in terms of technology, pathophysiology, and clinical application. In this review, the most recent research findings in the field of cardiovascular imaging are discussed. Artificial intelligence and large population cohorts, together with several technical improvements, have had a crucial impact on the technological advancements of echocardiography, cardiovascular magnetic resonance, computed tomography (CT), and nuclear medicine. In the field of ischaemic heart disease, it has been demonstrated that appropriate non-invasive imaging strategies improve patients' management and reduce invasive procedures and the need for additional testing at follow-up. Moreover, improvements in plaque characterization with CT are an expanding field of research with relevant implications for the prediction of disease severity, evolution, and response to treatment. In the field of valvular heart disease, imaging techniques have advanced alongside improvements in transcatheter treatment for aortic stenosis, mitral, and tricuspid regurgitation. Finally, in the field of heart failure and cardiomyopathies, cardiovascular imaging has reinforced its crucial role in early diagnosis and risk evaluation, showcasing advanced techniques that outperform traditional methods in predicting adverse outcomes., Competing Interests: Conflict of interest: G.P. received an honorarium as a speaker/consultant and an institutional research grant from GE Healthcare, Bracco, HeartFlow, Novartis, Alexion, and Menarini. All other authors have nothing to disclose., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Objective(s): We recently developed a new uptake index method for123I-metaiodobenzylguanidine (123I-MIBG) heart uptake measurements by using planarimages (radioisotope angiography and planar image) for the diagnosis of Lewy bodydisease (LBD), including Parkinson’s disease (PD) and dementia with Lewy bodies(DLB). However, the diagnostic accuracy of the uptake index was approximately equalto that of the heart-to-mediastinum ratio (H/M) for the discrimination of the LBD andnon-LBD patients. A simple and pain-free uptake index method using 123I-MIBG SPECTimages by modifying the uptake index method may show better diagnostic accuracythan the planar uptake index method. We hypothesized that the development of a newuptake index method for the determination of 123I-MIBG using single-photon emissioncomputed tomography (SPECT) imaging would provide a reliable and reproduciblediagnostic tool for clinical application. Regarding this, the purpose of this study wasto develop a new uptake index method with a simple protocol to determine 123I-MIBGuptake on SPECT.Methods: The 123I-MIBG input function was determined from the input counts of thepulmonary artery, assessed by analyzing the pulmonary artery time-activity curves.The 123I-MIBG output function was obtained from 123I-MIBG SPECT counts on the polarmap. The uptake index was calculated through dividing the output function by theinput function (SPECT uptake method). For the purpose of the study, 77 patientsunderwent 123I-MIBG SPECT, with an average of 31.5 min after clinical assessment andinjection of the tracer. The H/M values, as well as planar and SPECT uptake indiceswere calculated, and then correlated with clinical features.Results: According to the results, values obtained for LBD were significantly lower thanthose for non-LBD in all analyses (P

Aim. To estimate the prevalence of familial hypercholesterolemia (FH) in a sample of Moscow city and Moscow region patients with hypercholesterolemia (HCh) based on lipid spectrum and instrumental methods.Material and methods. The study included two samples of patients (age >18 years), with total cholesterol (TCh) level ≥7.5 mmol/l and/or low-density lipoprotein (LDL) cholesterol level ≥4.9 mmol/l. First sample (n=60) was included to determine secondary hyperlipidemia frequency in newly diagnosed HCh, with measurement of thyroid hormone, glucose and glycated hemoglobin (HbA1c) levels. Patients of the second sample (n=432) from Russian registry of FH (RuFH) were studied by drug therapy assessment, lipid profile measurements, calculation of FH probability according to Dutch and British criteria, carotids duplex scanning (CDS), cardiac perfusion single-photon emission computed tomography (SPECT/CT) using rest/stress protocol.Results. The incidence of secondary dyslipidemia due to diabetes or hypothyroidism in patients with severe HCh was 18.3%. Monotherapy with atorvastatin (34.2%) or rosuvastatin (31.8%), combined therapy with statins and other lipid-lowering drugs (24.4%) prevails in the structure of lipidlowering therapy in patients with severe HCh. The frequency of "definite" FH according to Dutch criteria in HCh patients was 15.3%, "probable" – 18.1%. Patients with definite FH diagnosis showed higher level of TCh (p

Pathological and experimental studies indicate the existence of a “penumbra” of progressive tissue damage and edema in regions immediately surrounding a hematoma in patients of intracerebral hemorrhage (ICH). This zone of oligemia surrounding ICH has a potential for perfusion recovery. Improved understanding of the pathophysiology of perilesional blood flow changes and brain injury after ICH may result in improved treatment strategies. The aim was to study perilesional blood flow changes in ICH by perfusion deficit(PD) measured by single‑photon emission computed tomography (SPECT) and to correlate it with the severity of ICH and outcome. Forty‑four patients of computed tomography (CT) documented nonlobar deep ICH suggestive of hypertensive hematoma of <7 days duration were subjected to 99mTc‑ethylene diacetate SPECT scans of the brain. Patients with significant midline shift (0.5 cm) or global blood flow reduction were excluded from the analysis. SPECT scan of the brain was analyzed by segmental analysis, a semi‑quantitative method of cerebral blood flow. A difference of radiotracer uptake of >10% between the region of interest of ICH cases and the ratio between the two ROI below 0.9 was taken as a significant PD. A correlation of PD was analyzed with that of various parameters such as the severity of stroke, duration from onset of ictus, and imaging including CT scan of the brain and SPECT scan. A statistically significant difference in the percentage of radiotracer uptake on comparison of ipsilateral and contralateral to ICH(P < 0.001) was observed, suggesting a significant hypoperfusion in the perilesional area in patients with ICH. A statistically significant correlation was noted between the severity of stroke and PD indicated by various parameters such as the National Institutes of Health Stroke Scale (NIHSS) score at admission (r = 0.328, P = 0.016), Glasgow Coma Scale (GCS) score at admission (r = −0.388, P = 0.005), and ICH score at admission (r = 0.314, P = 0.020). This study demonstrated more severe hypoperfusion in clinically severe ICH which is a possible explanation of poor outcomes in severe ICH cases. We observed hypoperfusion on SPECT study in 25 of 34 (73.5%) patients with subacute ICH and 5 of 10 patients (50%) with acute ICH. The mean time from the onset of ictus to SPECT scan done was 5.04 ± 1.75 days with a range of 1–7 days, suggesting the persistence of hypoperfusion in subacute stages too. This finding may be of clinical importance for identifying the salvageable area surrounding ICH for any possible intervention in future to improve the outcome. This study demonstrates that perilesional PD occurs in acute and subacute cases of ICH. This hypoperfusion is possibly time related and appears to be more severe in patients having major ICH with poor clinical and imaging parameters. This area of hypoperfusion or ischemic penumbra is a potential site for perfusion recovery to improve clinical outcomes and to reduce long‑term neurological deficits. [ABSTRACT FROM AUTHOR]

Background/Aims: Peptide receptor radionuclide therapy (PRRT) is becoming clinical routine for management of neuroendocrine tumours. The number of PRRT cycles is correlated with treatment effect but theoretically limited by off-target radiation damage to kidneys and bone marrow. New imaging biomarkers for assessment of PRRT tissue damage would enable evaluation of novel renal and bone marrow protective agents, as well as personalised PRRT treatment regiments. Methods: Mice treated with [177Lu]Lu-DOTA-TATE PRRT or vehicle were examined at baseline and following treatment with [18F]fluorothymidine (FLT) positron emission tomography (PET) and technetium-99m-mercapto-acetyl-tri-glycine ([99mTc]Tc-Mag3) single-photon emission tomography (SPECT) to assess dynamic changes in bone marrow proliferation and renal function, respectively. Results: Bone marrow proliferation as assessed by [18F]FLT was decreased 2 days after PRRT treatment, but not vehicle, compared to baseline (target-to-background ratio [TBRmax] baseline:1.69 ± 0.29 vs. TBRmax PRRT: 0.91 ± 0.02, p < 0.01). Renal function as assessed by [99mTc]Tc-Mag3 SPECT was similarly decreased 2 days following PRRT compared to vehicle (fractional uptake rate [FUR] vehicle: 0.030 ± 0.014 s–1 vs. FUR PRRT: 0.0051 ± 0.0028 s–1, p < 0.01). Conclusion: [18F]FLT PET and [99mTc]Tc-Mag3 SPECT are promising techniques for assessing bone marrow and renal injury from [177Lu]Lu-DOTA-TATE PRRT and may potentially improve patient management by allowing evaluation of protective interventions as well as enabling personalised PRRT treatments. [ABSTRACT FROM AUTHOR]

Background: The benefits of attenuation correction (AC) in technetium-99m myocardial perfusion imaging (MPI) have been well established. However, the value of thallium (Tl-201) AC and routine computed tomography AC (CTAC) were less well established. The aims of this study were to evaluate the diagnostic performance of thallium (Tl-201) MPI with additional CTAC and to determine which participants would benefit most.Methods and Results: A total of 108 consecutive patients who underwent Tl-201 MPI and received coronary angiography within 3 months were enrolled. Diagnostic performance was determined by sensitivity, specificity, and receiver operating characteristic curve analysis. Subgroup analyses were performed using gender and obesity. CTAC improved the area under the curve (0.84 vs. 0.77, P = 0.037 at patient level), primarily due to a significant improvement in specificity (0.78 vs. 0.57, P = 0.013) and no significant difference in sensitivity (0.79 vs. 0.82, P = 0.75). In subgroup analysis, CTAC was most helpful in obese subjects, men, and especially right coronary artery lesions.Conclusions: CTAC significantly improved diagnostic performance primarily by increasing the specificity, and the improvements were significantly greater in obese patients and male patients. These findings suggest that CTAC should be applied to Tl-201 MPI as routine clinical practice. [ABSTRACT FROM AUTHOR]

Background and purpose: Diphenylarsinic acid (DPAA) intoxication caused by drinking contaminated well water was found in Kamisu, Japan. The symptoms indicated cerebellar–brainstem and temporo‐occipital involvement. However, it remains unclear how it affects the human brain. To elucidate the effect of DPAA on the human brain, we analyzed cerebral blood flow (CBF) data after the drinking of DPAA‐contaminated water was stopped and investigated the correlation between DPAA exposure level and CBF by single‐photon emission computed tomography (CBF‐SPECT). Methods: The DPAA‐exposed inhabitants (n = 78) were divided into 35 symptomatic and 43 asymptomatic subjects and compared with 38 healthy controls. The DPAA concentration in nails or hair and well water was measured using a high‐performance liquid chromatography system and coupled plasma mass spectrometry after adequate extraction treatment. CBF‐SPECT data, obtained within 1 year after the drinking of contaminated well water was stopped, were analyzed by statistical parametric mapping. We also examined the relationship between variations in CBF‐SPECT signals and variations in DPAA concentrations in the hair or nails of the subjects. Results: Compared with control subjects, CBF in symptomatic DPAA‐exposed subjects was significantly lower in the occipital lobe, including the cuneus and inferior occipital gyri. The DPAA concentration in the nails or hair of subjects was inversely and significantly related to their CBF. Conclusion: These data suggest that CBF‐SPECT may be useful as a clinical marker to infer the effect of accumulated DPAA on the brain. [ABSTRACT FROM AUTHOR]

Background: Disease State Index (DSI) and its visualization, Disease State Fingerprint (DSF), form a computer-assisted clinical decision making tool that combines patient data and compares them with cases with known outcomes. Aims: To investigate the ability of the DSI to diagnose frontotemporal dementia (FTD) and Alzheimer's disease (AD). Methods: The study cohort consisted of 38 patients with FTD, 57 with AD and 22 controls. Autopsy verification of FTD with TDP-43 positive pathology was available for 14 and AD pathology for 12 cases. We utilized data from neuropsychological tests, volumetric magnetic resonance imaging, single-photon emission tomography, cerebrospinal fluid biomarkers and the APOE genotype. The DSI classification results were calculated with a combination of leave-one-out cross-validation and bootstrapping. A DSF visualization of a FTD patient is presented as an example. Results: The DSI distinguishes controls from FTD (area under the receiver-operator curve, AUC = 0.99) and AD (AUC = 1.00) very well and achieves a good differential diagnosis between AD and FTD (AUC = 0.89). In subsamples of autopsy-confirmed cases (AUC = 0.97) and clinically diagnosed cases (AUC = 0.94), differential diagnosis of AD and FTD performs very well. Conclusions: DSI is a promising computer-assisted biomarker approach for aiding in the diagnostic process of dementing diseases. Here, DSI separates controls from dementia and differentiates between AD and FTD.

Even when concussions are associated with prolonged physical and cognitive sequelae, concussions are typically “invisible” on diagnostic brain imaging, indicating that the neuropathology associated with concussion lies under the detection threshold of routine imaging. However, data from brain structural and functional research imaging studies using diffusion tensor imaging, resting‐state functional magnetic resonance imaging, and brain perfusion imaging indicate that these imaging sequences have a role in identifying concussion‐related neuropathology. These advanced imaging techniques provide insights into concussion neuropathology and might be useful for differentiating concussed patients from healthy controls. In this review article, we provide an overview of research findings from brain structural and functional imaging studies of concussion, and discuss the accuracy of classification models developed via machine‐learning algorithms for identifying individual patients with concussion based on imaging data. [ABSTRACT FROM AUTHOR]

Background: Anosognosia in Alzheimer's disease (AD) is a complicated, non‐unitary phenomenon. In a clinical setting, patients with mild AD often preserve their awareness partially. We hypothesized that compensation, as well as neural dysfunction, could be correlated with anosognosia in mild AD. Methods: The severity of anosognosia was evaluated using the Anosognosia Questionnaire for Dementia in 37 subjects with mild AD or mild cognitive impairment due to AD. The subjects also underwent single‐photon emission computed tomography with N‐isopropyl‐p‐[123I]iodoamphetamine. Correlation between the severity of anosognosia and perfusion was assessed, and anosognosia (+) and (−) groups were compared. Results: The severity of anosognosia was relatively mild; the mean Anosognosia Questionnaire for Dementia score was 6.76 ± 14.16. Subjects were divided into two groups: anosognosia (+) (n = 11) and anosognosia (−) (n = 26). In the single‐photon emission computed tomography data analysis, the severity of anosognosia was correlated with both lower regional cerebral blood flows of the right prefrontal cortex and higher regional cerebral blood flows of the parietal cortex, especially the left temporo‐parietal junction. Conclusions: Our results suggest that anosognosia in mild AD could be correlated with compensation as well as neural dysfunction. We speculate that this compensation may be related to the retrieval of outdated autobiographical memory. [ABSTRACT FROM AUTHOR]

Objective(s): We recently developed a new uptake index method for 123I-metaiodobenzylguanidine (123I-MIBG) heart uptake measurements by using planar images (radioisotope angiography and planar image) for the diagnosis of Lewy body disease (LBD), including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). However, the diagnostic accuracy of the uptake index was approximately equal to that of the heart-to-mediastinum ratio (H/M) for the discrimination of the LBD and non-LBD patients. A simple and pain-free uptake index method using 123I-MIBG SPECT images by modifying the uptake index method may show better diagnostic accuracy than the planar uptake index method. We hypothesized that the development of a new uptake index method for the determination of 123I-MIBG using single-photon emission computed tomography (SPECT) imaging would provide a reliable and reproducible diagnostic tool for clinical application. Regarding this, the purpose of this study was to develop a new uptake index method with a simple protocol to determine 123I-MIBG uptake on SPECT. Methods: The 123I-MIBG input function was determined from the input counts of the pulmonary artery, assessed by analyzing the pulmonary artery time-activity curves. The 123I-MIBG output function was obtained from 123I-MIBG SPECT counts on the polar map. The uptake index was calculated through dividing the output function by the input function (SPECT uptake method). For the purpose of the study, 77 patients underwent 123I-MIBG SPECT, with an average of 31.5 min after clinical assessment and injection of the tracer. The H/M values, as well as planar and SPECT uptake indices were calculated, and then correlated with clinical features. Results: According to the results, values obtained for LBD were significantly lower than those for non-LBD in all analyses (P<0.01). The overlap of the H/M values between the LBD and non-LBD cases ranged from 2.06 to 2.50. Furthermore, the overlap in uptake index values between LBD and non-LBD cases in planar image analysis was 1.05-1.29. The SPECT uptake index method showed the least overlap of 1.23-1.25, with the highest value for LBD patients clearly distinguished from the lowest value for the non- LBD patients. Conclusion: The new 123I-MIBG SPECT quantification method, developed by the input counts of the pulmonary artery, clearly distinguished LBD from non-LBD. Therefore, this method may be appropriate for routine clinical study. [ABSTRACT FROM AUTHOR]

As the second term of our commitment to Journal begins, we, the editors, would like to reflect on a few topics that have relevance today. These include prognostication and paradigm shifts; Serial testing: How to handle data? Is the change in perfusion predictive of outcome and which one? Ischemia-guided therapy: fractional flow reserve vs perfusion vs myocardial blood flow; positron emission tomography (PET) imaging using Rubidium-82 vs N-13 ammonia vs F-18 Flurpiridaz; How to differentiate microvascular disease from 3-vessel disease by PET? The imaging scene outside the United States, what are the differences and similarities? Radiation exposure; Special issues with the new cameras? Is attenuation correction needed? Are there normal databases and are these specific to each camera system? And finally, hybrid imaging with single-photon emission tomography or PET combined with computed tomography angiography or coronary calcium score. We hope these topics are of interest to our readers. [ABSTRACT FROM AUTHOR]

Pulmonary embolism (PE) is a common, ubiquitous, and potentially lethal disease. As symptoms and clinical findings are notoriously nonspecific, diagnostic imaging is essential to avoid undertreatment as well as overtreatment. Controversies remain regarding first-line imaging in suspected PE. The two main contemporary contenders are ventilation/perfusion scintigraphy with single-photon emission computed tomography (V/Q SPECT) with or without additional low-dose CT (SPECT/CT) and CT angiography (CTA). We present our results from a systematic review and meta-analysis of the diagnostic performances of thesemodalities: V/Q SPECT, V/Q SPECT/CT, and CTA are all viable options, but we consider V/Q SPECT/CT to be superior in most clinical settings with better overall diagnostic performance, that is, pooled sensitivities (97.6 vs. 82.0%), specificities (95.9 vs. 94.9%), positive predictive values (93.0 vs. 93.8%), negative predictive values (98.6 vs. 84.7%), and accuracies (96.5 vs. 88.6%). We further address some of the ongoing controversies regarding the various modalities, that is, radiation exposure, the issues of subsegmental PE, nondiagnostic studies, and various challenges in specific patient populations. [ABSTRACT FROM AUTHOR]

Premotor Parkinson's disease ( PD) refers to a prodromal stage of Parkinson's disease ( PD) during which nonmotor clinical features may be present. Currently, it is difficult to make an early diagnosis for premotor PD. Molecular imaging with position emission tomography ( PET) or single-photon emission tomography ( SPECT) offers a wide variety of tools for overcoming this difficulty. Indeed, molecular imaging techniques may play a crucial role in diagnosing, monitoring and evaluating the individuals with the risk for PD. For example, dopaminergic dysfunctions can be identified by detecting the expression of vesicular monoamine transporter ( VMAT2) and aromatic amino acid decarboxylase ( AADC) to evaluate the conditions of dopaminergic terminals functions in high-risk individuals of PD. This detection provides a sensitive and specific measurement of nonmotor symptoms ( NMS) such as olfactory dysfunction, sleep disorders, and psychiatric symptoms in the high-risk patients, especially at the premotor phase. Molecular imaging technique is capable of detecting the dysfunction of serotonergic, noradrenergic, and cholinergic systems that are typically associated with premotor manifestations. This review discusses the importance of SPECT/ PET applications in the detection of premotor markers preceding motor abnormalities with highlighting their great potential for early and accurate diagnosis of premotor symptoms of PD and its scientific significance. [ABSTRACT FROM AUTHOR]

Background/Aim: We developed a test named the Card Placing Test (CPT), which is potentially useful for evaluating a function of the retrosplenial and posterior cingulate cortices (RSC/PCC). Part A of the test assesses the ability of a subject to retain information on spatial locations of cards placed on the floor around the subject. Part B examines the subject's ability to integrate information on the spatial locations of similarly arranged cards and information on changes in body direction. The aim of this study is to identify brain regions involved in the CPT performance. Subjects and Methods: Twenty-five subjects were recruited from our memory clinic. We analyzed the correlation between the CPT scores and resting state regional cerebral blood flow (rCBF) determined by single-photon emission tomography. Results: The scores for part A correlated with rCBF in the right inferior parietal lobule. The scores for part B were associated with rCBF in the RSC/PCC. Conclusions: The right inferior parietal lobule seems to play a pivotal role in performing part A of the CPT, whereas the RSC/PCC appears to be involved in accomplishing part B of the CPT. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Myocardial perfusion imaging (MPI) with gated single-photon emission tomography provides important information on the extent and severity of myocardial perfusion abnormalities, including myocardial ischemia. The availability of software for automated quantitative assessment of myocardial perfusion in an objective and more reproducible manner than visual assessment has allowed MPI to be particularly effective in serial evaluation. Serial testing using MPI is widely used in guiding patient care despite the lack of well-defined appropriateness use criteria. This should not be surprising because ischemic heart disease is a life-long malady subject to dynamic changes throughout its natural course and particularly following man-made interventions that may improve or worsen the disease process, such as medical therapy and coronary revascularization. Serial MPI has filled an important clinical gap by providing crucial information for managing patients with changes in clinical presentations or in anticipation of such changes in patients with stable symptoms. In the research arena, serial MPI has been widely applied in randomized controlled trials to study the impact of various medical and interventional therapies on myocardial perfusion, as well as the relative merits of new imaging procedures (hardware and/or software), radiotracers, and stressor agents. Serial testing, however, unlike initial or 1-time testing, has more stringent requirements and is subject to variability because of technical, procedural, interpretational, and biological factors. The intrinsic variability of MPI becomes important in interpreting serial tests in order to define a true change in a given patient and to guide clinical decision making. The purpose of this first comprehensive review on this subject is to illustrate where serial MPI may be useful clinically and in research studies, and to highlight strategies for addressing the various issues that are unique to serial testing in order to derive more valid and robust data from the serial scans. [Copyright &y& Elsevier]

Dopaminergic availability is known to linearly decline in Parkinson's disease (PD). In contrast, temporal characteristics of serotonergic markers like the serotonin transporter (SERT) in relation to clinical staging of PD and dopaminergic cell loss are less clear. This study investigated SERT availability using [I]-ADAM and single-photon emission tomography (SPECT) in drug-naive, de novo patients, i.e., in a PD stage where dopaminergic decline starts to lead to the occurence of the characteristic motor symptoms. Nine de novo patients with PD and 9 age-matched healthy controls were studied. Measurements were repeated after 3 months of levodopa treatment in patients with PD, and dopaminergic transporter (DAT) binding was examined at baseline using [I]-FP-CIT SPECT. No alterations of SERT availability were found between groups, and neither correlation between SERT and DAT nor effects of levodopa treatment on SERT was found in patients with PD. These preliminary findings indicate that midbrain SERT is preserved in unmedicated patients at this early stage of PD, supporting the view that serotonergic decline temporally follows dopaminergic cell loss. [ABSTRACT FROM AUTHOR]

We evaluated the effects of olmesartan, an angiotensin II receptor blocker (ARB), on cerebral blood flow (CBF) in elderly and hypertensive subjects. Ten subjects with first- or second-degree essential hypertension (mean age, 70.5 years) underwent brain single-photon emission tomography (SPECT) scanning with 99mTc-ethyl cysteinate dimer before and after a 24-week course of olmesartan. Mean systolic blood pressure (SBP) was 156.2±9.9mm Hg, and mean diastolic blood pressure (DBP) was 89.1±5.5mm Hg. No subject had any abnormalities on neurologic examination or previous history of stroke or cardiovascular disease. Before olmesartan administration, the hypertensive subjects had approximately 15% less whole brain CBF compared with age-matched normotensive controls. Regional CBF was decreased by 11%-20% in the frontal, parietal, temporal, and posterior lobes. Olmesartan treatment significantly decreased SBP to 130.4±4.2mm Hg (P < .001) and DBP to 78.2±7.0mm Hg (P < .001). After 24 weeks of olmesartan treatment, CBF of whole brain and regional CBF of the frontal, parietal, and temporal lobe were similar to those of control subjects. Our brain SPECT data indicate that olmesartan restores brain hypoperfusion in elderly and hypertensive patients without organic damage. This ARB may have a favorable potential for cerebrovascular circulation, in addition to a blood pressure–lowering effect. [Copyright &y& Elsevier]

Background Perfusion cardiovascular magnetic resonance (CMR) has a high sensitivity for the detection of significant coronary artery disease (CAD). However, the specificity of this method is lower than its sensitivity. The reason for this observation is hitherto unclear and has been either explained by 'false-positive' results or by microvascular dysfunction in patients without CAD. Objective To evaluate whether pathological myocardial perfusion-CMR imaging in symptomatic patients without significant CAD is associated with coronary epicardial or microvascular dysfunction. Methods In this retrospective study, 42 patients who presented with unstable angina pectoris underwent (a) an adenosine-stress perfusion-CMR study; (b) coronary angiography; (c) intracoronary acetylcholine (ACh) testing following coronary angiography with exclusion of significant CAD. The CMR protocol comprised cine imaging followed by adenosine first-pass perfusion imaging and late gadolinium enhancement-CMR. Diagnostic left ventriculography and multiplane coronary angiography were performed before intracoronary ACh testing. Results An adenosine-induced, reversible subendocardial perfusion defect was detected in 22/42 patients (52%) without significant CAD. Coronary epicardial vasospasm was detected in 10/42 patients (24%) while microvascular dysfunction was found in 20/42 patients (48%). Patients with a reversible stress-induced perfusion defect had significantly more often a pathological coronary epicardial or microvascular vasoreaction (20/22; 91%) during intracoronary ACh testing than those without a perfusion defect (10/20; 50%; p<0.01). Univariate correlation analyses revealed a substantial association between a pathological ACh-testing result and a perfusion defect in the antecedent CMR study (r= +0.45; p<0.01). Conclusions Reversible perfusion defects depicted by perfusion-CMR in patients without significant CAD are mostly due to coronary epicardial or microvascular dysfunction, and correct interpretation of such perfusion-CMR results may enable targeted treatment. [ABSTRACT FROM AUTHOR]

Advances in neuroimaging over the past 5-10 years have offered opportunities to address challenging and previously unanswered clinical questions in ophthalmologic neuroimaging. Among these advances are diffusion-weighted imaging, diffusion-tensor imaging (DTI), perfusion MRI (PWI), functional MRI (fMRI) as well as single-photon emission tomography, PET scanning and high-frequency contrast harmonic ultrasound imaging. The MRI techniques are based on imaging the static or dynamic changes of the hydrogen proton in a controlled magnetic field. Diffusion-weighted imaging, for instance, offers temporal characterization of acute infarction and differentiation of neoplasm from bacterial abscess, or differentiation between certain types of neoplasms that may present with visual symptoms. The addition of PWI allows rapid assessment of tissue at risk (penumbra) beyond the core (umbra) in the setting of acute stroke. PWI, computed tomography perfusion and high-frequency contrast harmonic imaging are used to study the perfusion characteristics of the ocular tumors for determination of their prognosis. PWI is also being studied for its utility in histopathologic grading of intracranial tumors. DTI and fMRI offer new insights into presurgical planning of the brain tumor resection. DTI helps to identify the retrochiasmatic optic pathways. Importantly, such fibertracking by DTI enables the differentiation of invasive from displacing lesions. fMRI is also being studied for its utility to identify retinotopic borders, motion processing, visual attention and patients with visual defects. Furthermore, the combination of both fiber tracking and fMRI offers the opportunity to demonstrate not only spatial networks within the brain but also temporal activation and recruitment of components of such networks. Single-photon emission tomography and PET scanning are helpful for the noninvasive estimation of the cerebral visual function, as well as the evaluation of functional recovery in patients. With these advancements, neuroradiology continues to lead the transition of diagnostic imaging from anatomic to physiologic and molecular imaging. [ABSTRACT FROM AUTHOR]

Interventions to treat coronary artery disease are available but they must be targeted at the correct individuals (and indeed lesions), in order to gain maximal benefit with the minimal adverse effects. Coronary contrast angiography is not able to provide all the information required for the assessment of the effects of artery disease. Other imaging modalities are of growing importance as they can reduce radiation exposure and invasiveness of screening, as well as providing important extra information. The ideal 'multiparametric' imaging technique would assess anatomy, viability and lesion activity in a single quick scan. Currently, MRI is the technology closest to achieving this ideal, although the existing technology still has some limitations. This review discusses the currently available techniques for the imaging of coronary anatomy and of myocardial viability, and considers their benefits and limitations. We also discuss the developing field of imaging molecularly targeted to active coronary lesions. Finally we provide a 5-year view of the current and likely future optimal imaging strategies. [ABSTRACT FROM AUTHOR]

Abstract: The present work describes the development of a new detection technology for medical imaging using the method of Single-Photon Emitted Computed Tomography (SPECT) combined with X-rays Computed Tomography (CT). Our ultimate goal is to advance disease detection by imaging quantitatively molecular agents and localizing their distribution in tissues and organs by SPECT simultaneously with the anatomical CT image. To assess the imaging characteristics of the imaging agents developed, we tested and advanced a detection technique first developed for high-energy physics: Gas Electron Multipliers (GEMs). [Copyright &y& Elsevier]