Clinical and Prognostic Implications of Right Ventricular Uptake on Bone Scintigraphy in Transthyretin Amyloid Cardiomyopathy.

BACKGROUND: The extent of myocardial bone tracer uptake with technetium pyrophosphate, hydroxymethylene diphosphonate, and 3,3-diphosphono-1,2-propanodicarboxylate in transthyretin amyloid cardiomyopathy (ATTR-CM) might reflect cardiac amyloid burden and be associated with outcome. METHODS: Consecutive patients with ATTR-CM who underwent diagnostic bone tracer scintigraphy with acquisition of whole-body planar and cardiac single-photon emission computed tomography (SPECT) images from the National Amyloidosis Centre and 4 Italian centers were included. Cardiac uptake was defined according to the Perugini classification: 0=absent cardiac uptake; 1=mild uptake less than bone; 2=moderate uptake equal to bone; and 3=high uptake greater than bone. Extent of right ventricular (RV) uptake was defined as focal (basal segment of the RV free wall only) or diffuse (extending beyond basal segment) on the basis of SPECT imaging. The primary outcome was all-cause mortality. RESULTS: Among 1422 patients with ATTR-CM, RV uptake accompanying left ventricular uptake was identified by SPECT imaging in 100% of cases at diagnosis. Median follow-up in the whole cohort was 34 months (interquartile range, 21 to 50 months), and 494 patients died. By Kaplan-Meier analysis, diffuse RV uptake on SPECT imaging (n=936) was associated with higher all-cause mortality compared with focal (n=486) RV uptake (77.9% versus 22.1%; P<0.001), whereas Perugini grade was not associated with survival (P=0.27 in grade 2 versus grade 3). On multivariable analysis, after adjustment for age at diagnosis (hazard ratio [HR], 1.03 [95% CI, 1.02-1.04]; P<0.001), presence of the p.(V142I) TTR variant (HR, 1.42 [95% CI, 1.20-1.81]; P=0.004), National Amyloidosis Centre stage (each category, P<0.001), stroke volume index (HR, 0.99 [95% CI, 0.97-0.99]; P=0.043), E/e' (HR, 1.02 [95% CI, 1.007-1.03]; P=0.004), right atrial area index (HR, 1.05 [95% CI, 1.02-1.08]; P=0.001), and left ventricular global longitudinal strain (HR, 1.06 [95% CI, 1.03-1.09]; P<0.001), diffuse RV uptake on SPECT imaging (HR, 1.60 [95% CI, 1.26-2.04]; P<0.001) remained an independent predictor of all-cause mortality. The prognostic value of diffuse RV uptake was maintained across each National Amyloidosis Centre stage and in both wild-type and hereditary ATTR-CM (P<0.001 and P=0.02, respectively). CONCLUSIONS: Diffuse RV uptake of bone tracer on SPECT imaging is associated with poor outcomes in patients with ATTR-CM and is an independent prognostic marker at diagnosis.

A systematic literature review and meta-analysis of spectral CT compared to scintigraphy in the diagnosis of acute and chronic pulmonary embolisms.

PURPOSE: To examine the diagnostic accuracy of spectral CT pulmonary angiography (S-CTPA) using ventilation-perfusions lung scintigraphy (V/Q-scan) as a reference standard in the diagnosis of acute or chronic pulmonary embolism (APE/CPE) and chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: PubMed, Embase, Scopus, and Web of Science were searched for the period from 1 Jan 2006 to 7 Feb 2019; eligible studies had > 10 patients over 18 years old, a diagnostic outcome of PE or CTEPH, and used V/Q scan as a reference standard. Bias and applicability were assessed using QUADAS-2 tools. Sensitivities, specificities, and predictive values were noted or calculated from available information. Meta-analysis employed a fixed-effects model of Mantel and Haenszel. Heterogeneity was assessed with I-squared statistics. RESULTS: Four hundred ninety-three unique records were identified. Following screening by title, 53 studies were included in the abstract and full-text assessment. A total of six articles were included; four were suitable for a meta-analysis. Pooled sensitivity was 94.2% (95% CI, 88.3-100%), pooled specificity was 88.5% (95% CI, 81.3-95.6%), and positive and negative predictive values were 87.8% (95% CI, 80.3-95.4%) and 94.5% (95% CI, 89.3-99.7%), respectively. CONCLUSION: Data on S-CTPA for PE/CTEPH remains promising, but limited; only small studies with methodological issues are available. Evidence is best for CPE/CTEPH whereas no firm conclusions are possible for APE. There is a need for larger, prospective studies with a robust composite reference standard including state-of-the-art CTPA and V/Q-scans. KEY POINTS: • S-CTPA has high sensitivity and specificity for perfusion defects in patients with PE or CPETH. • Methodological issues and diversity of reference standards were found in the small number of included studies. • There is a need for larger prospective studies with more robust composite reference standards.

The diagnostic value of SPECT/CT in predicting the occurrence of osteonecrosis following femoral neck fracture: a prospective cohort study.

BACKGROUNDS: One of the most significant complications after a femoral neck fracture is osteonecrosis of the femoral head (ONFH). The concomitant use of single-photon emission computed tomography (SPECT) with computed tomography (CT) increases the sensitivity for detecting the anatomic location and severity of ONFH. In this study, we evaluated the diagnostic value of SPECT/CT for the occurrence of ONFH by quantifying the perfusion status of the femoral head. METHODS: A total of 30 patients who had multiple pinnings for femur neck fractures were included in this study. We classified the perfusion status into three groups: normal perfusion, decreased perfusion, and avascular groups, and compared the occurrence of femoral head necrosis between them. For quantitative analysis, we evaluated the uptake ratio of both femur heads (head-to-head uptake ratio). If the patient's contralateral hip was incomparable, we measured the uptake ratio from the superior dome of the ipsilateral acetabulum (head-to-acetabulum uptake ratio). RESULTS: Twenty-four patients out of 30 achieved bone union, whereas the others developed ONFH. When the population was divided into intact and defective perfusion groups on scintigraphy, the sensitivity, specificity, and accuracy of the test were 83.3, 75.0, and 76.7%, respectively. The mean head-to-head uptake ratio value with a 95% confidence interval (CI) was 1.10 (95% CI: 0.85-1.36). In the osteonecrosis group, the mean value of the head-to-head uptake ratio was 0.33 (95% CI: 0.28-0.38). In contrast, the ratio was 1.30 (95% CI: 1.03-1.57) in the non-osteonecrosis group, demonstrating a significant difference in the uptake ratio (P < 0.001). When the cutoff value of the uptake ratio was set to 0.5, both the sensitivity and specificity were 100%. There was also a significant difference in the head-to-acetabulum uptake ratio between the two groups (P <  0.001). CONCLUSIONS: SPECT/CT was useful in evaluating the perfusion status of the femoral head, showing high accuracy in predicting the occurrence of avascular necrosis. To demonstrate the reliability and validity of SPECT/CT, further prospective studies on a larger scale are warranted.

Correlation between the availability of dopamine transporter and olfactory function in healthy subjects.

OBJECTIVES: Olfactory dysfunction in Parkinson's disease is usually prodromal to other symptoms. In this study, we aimed to explore the association of olfactory function with the availabilities of striatal dopamine transporter (DAT) in healthy subjects. METHODS: Data used in the preparation of this article were obtained from Parkinson's Progression Markers Initiative database ( www.ppmi-info.org/data ). The study population consisted of healthy controls with screening 123I-FP-CIT single photon emission tomography (SPECT). University of Pennsylvania Smell Identification Test (UPSIT) was assessed to evaluate the olfactory function. RESULTS: Totally, 181 healthy subjects (117 male, 64 female) with 123I-FP-CIT SPECT data were included in this study. Specific binding ratios (SBRs) of the caudate nucleus (rho = -0.4217, p < 0.0001), putamen (rho = -0.2292, p = 0.0019), and striatum (rho=-0.3425, p < 0.0001) showed a reduction with ageing. SBRs of the caudate nucleus, putamen, and striatum were positively correlated with UPSIT (rho = 0.3716, p < 0.0001; rho = 0.3655, p < 0.0001; rho = 0.3880, p < 0.0001). After controlling for age by partial correlation, SBRs of the caudate nucleus, putamen, and striatum showed an influence on UPSIT (rho = 0.3288, p < 0.0001; rho = 0.3374, p < 0.0001; rho = 0.3511, p < 0.0001). CONCLUSION: Olfactory function is associated with the availability of striatal DAT independent of age in healthy subjects. KEY POINTS: • Olfactory dysfunction in Parkinson's disease is prodromal to other symptoms. • The availability of dopamine transporter showed a reduction with ageing. • Olfactory function is associated with the availability of dopamine transporter.

[Relationship between coronary tortuosity and coronary microvascular disease].

Objective: To explore the relationship between coronary tortuosity and coronary microvascular disease (CMVD). Methods: Patients with typical angina symptoms and without serious coronary artery stenosis by coronary angiography were enrolled from June 2014 to December 2016, and CMVD was diagnosed by single photon emission tomography (SPECT). According to the SPECT results, patients were divided to the CMVD group and non-CMVD group. The baseline clinical characteristics, results of coronary angiography were compared between the two groups. The logistic analysis was used to analyze the relationship between coronary tortuosity and CMVD. Result: A total of 117 cases were enrolled, with 69 cases in the CMVD group and 48 cases in the non-CMVD group. No differences were found in gender distribution, age, hypertension, lipid abnormality, hyperuricemia and uses of statins between the two groups (all P>0.05). Incidence of diabetes (78.26%(54/69) vs. 35.42% (17/48) , P<0.05), hs-CRP ((4.29±2.15)mmol/L vs. (2.63±1.20)mmol/L, P<0.001), LDL-C ((2.98±0.96)mmol/L vs. (2.52±0.83)mmol/L, P=0.008) and homocysteine ((13.7±5.61)mmol/L vs. (11.5±4.38)mmol/L, P=0.025) levels were higher in the CMVD group than in the non-CMVD group. The data derived from echocardiographic examination were similar between the two groups. The Corrected TIMI frame counts were higher in the CMVD group than in non-CMVD group (LAD: 31.56±4.92 vs. 27.31±3.75, LCX: 29.47±4.18 vs. 26.62±3.19, RCA: 29.09±5.05 vs. 26.24±3.28, all P<0.001). The incidences of coronary atherosclerosis (76.81% (53/69) vs. 27.08% (13/48) , P<0.001) and coronary tortuosity ( (60.87% (42/69) vs. 33.33% (16/48) , P=0.035) were also higher in the CMVD group than in non-CMVD group. Logistic analysis found that coronary tortuosity (OR=6.111, 95%CI 2.707-13.794, P<0.001), diabetes (OR=6.565, 95%CI 2.883-14.948, P<0.001) and coronary atherosclerosis (OR=8.918, 95%CI 3.822-20.808, P<0.001) were independent risk factors of CMVD. Conclusion: Coronary tortuosity, diabetes and coronary atherosclerosis are related to CMVD in this patient cohort.

[Value of (99)Tc(m)-MDP SPECT/CT in clinical decision-making for nasopharyngeal carcinoma and a comparison of the values of different imaging techniques for diagnosing skull-base bone invasion].

Objective: To analyze the clinical value of SPECT/CT in diagnosis of skull base bone invasion and clinical decision-making for nasopharyngeal carcinoma (NPC), and to compare their diagnostic value with SPECT/CT, CT, MRI, and MRI combined with SPECT (MRI-SPECT) for skull base bone invasion. Methods: Before treatment, among 348 newly diagnosed NPC patients, CT scan was performed in 186 patients (group A) and the remaining 162 patients received MRI scan (group B). Clinical doctors then made clinical management decisions according to the CT or MRI results. After that, all patients underwent (99)Tc(m)-MDP SPECT/CT examination for nasopharyngeal local tomography, and the results were provided to the clinical doctors to make clinical management decisions again. The changes between the two clinical management decisions were scored according to diagnosis, range of lesion, staging, treatment regimens, and auxiliary examination. The diagnostic value of CT scan, MRI scan, SPECT/CT and MRI-SPECT for skull base bone invasion was then evaluated and compared. Results: In terms of changes in scores of clinical management decisions, the score of group A was 1.387 and group B was 0.951, showing a significant difference between the two groups by Wilcoxon test (Z=6.570, P<0.001). By χ(2) test, there were correlations between CT and SPECT/CT (χ(2) =98.495, P<0.001), and between MRI and SPECT/CT (χ(2) =32.662, P<0.001). The consistency of CT and SPECT/CT (Kappa=0.713) was greater than MRI and SPECT (Kappa=0.449). The sensitivity of CT, MRI, SPECT/CT and MRI-SPECT was 67.1%, 84.5%, 90.8% and 100%, the specificity was 73.3%, 92.3%, 85.6% and 84.6%, and the area under the ROC curve was 0.702, 0.884, 0.882 and 0.923, respectively. Conclusions: SPECT/CT has important impact on clinical management decision for NPC. In the judgement of skull base invasion, the diagnostic value of SPECT/CT is significantly higher than CT and approximately equal to MRI. SPECT/CT should be one of the routine examination methods of nasopharyngeal carcinoma. In addition, in view of its greater diagnostic value, MRI combined with SPECT should be the focus of future imaging studies.

[Application of γ imaging in chromatographic separation and protein molecular site density determination].

We in this study measured the site density of E-selectin in order to explore the practical pliability using radionuclide labeling method and γ-imaging of single photon emission computer tomography (SPECT). This method required labeling of antibody with 125I using Indogen method and binding of the labeled antibody to E-selectin. Labeled E-selectin was separated and purified in a Sephadex G25 column. The different fractions of the eluants were imaged, analyzed and quantified with SPECT method. For measuring the saturation curve of E-selectin, 130 µL of E-selectin solution with different concentrations were added in a 48-well plate and incubated overnight at 4℃. After incubation, 130 µL of labeled antibody solution were added and kept incubated for 30 min. The resulted mixture was washed, and the radioactivity in each sample was detected by SPECT. The levels of radioactivity were translated to site densities, and were used to plot a standard curve. The labeled product was quantitatively analyzed with SPECT. The labeling rate of E-selectin was 78%. The saturation curve of different concentration samples showed that when the concentration was in the concentration range of 0-1 mg/mL, the standard curve was y=6 045.7 x-51.166, R2=0.997 9. Based on this finding, it could be concluded that γ-imaging is an important tool for analysis of radiolabeled product and determination of site density.

Comparison of cardiovascular magnetic resonance and single-photon emission computed tomography in women with suspected coronary artery disease from the Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease (CE-MARC) Trial.

BACKGROUND: Coronary artery disease is the leading cause of death in women, and underdiagnosis contributes to the high mortality. This study compared the sex-specific diagnostic performance of cardiovascular magnetic resonance (CMR) and single-photon emission computed tomography (SPECT). METHODS AND RESULTS: A total of 235 women and 393 men with suspected angina underwent CMR, SPECT, and x-ray angiography as part of the Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease (CE-MARC) study. CMR comprised adenosine stress/rest perfusion, cine imaging, late gadolinium enhancement, and magnetic resonance coronary angiography. Gated adenosine stress/rest SPECT was performed with (99m)Tc-tetrofosmin. For CMR, the sensitivity in women and men was similar (88.7% versus 85.6%; P=0.57), as was the specificity (83.5% versus 82.8%; P=0.86). For SPECT, the sensitivity was significantly worse in women than in men (50.9% versus 70.8%; P=0.007), but the specificities were similar (84.1% versus 81.3%; P=0.48). The sensitivity in both the female and male groups was significantly higher with CMR than SPECT (P<0.0001 for both), but the specificity was similar (P=0.77 and P=1.00, respectively). For perfusion-only components, CMR outperformed SPECT in women (area under the curve, 0.90 versus 0.67; P<0.0001) and in men (area under the curve, 0.89 versus 0.74; P<0.0001). Diagnostic accuracy was similar in both sexes with perfusion CMR (P=1.00) but was significantly worse in women with SPECT (P<0.0001). CONCLUSIONS: In both sexes, CMR has greater sensitivity than SPECT. Unlike SPECT, there are no significant sex differences in the diagnostic performance of CMR. These findings, plus an absence of ionizing radiation exposure, mean that CMR should be more widely adopted in women with suspected coronary artery disease. CLINICAL TRIAL REGISTRATION URL: http://www.controlled-trials.com. Unique identifier: ISRCTN77246133.

Impact of appropriate use on the prognostic value of single-photon emission computed tomography myocardial perfusion imaging.

BACKGROUND: Appropriate use criteria (AUC) have been developed to aid in the optimal use of single-photon emission computed tomography (SPECT)-myocardial perfusion imaging (MPI), a technique that is a mainstay of risk assessment for ischemic heart disease. The impact of appropriate use on the prognostic value of SPECT-MPI is unknown. METHODS AND RESULTS: A prospective cohort study of 1511 consecutive patients undergoing outpatient, community-based SPECT-MPI was conducted. Subjects were stratified on the basis of the 2009 AUC for SPECT-MPI into an appropriate or uncertain appropriateness group and an inappropriate group. Patients were prospectively followed up for 27±10 months for major adverse cardiac events of death, death or myocardial infarction, and cardiac death or myocardial infarction. In the entire cohort, the 167 subjects (11%) with an abnormal scan experienced significantly higher rates of major adverse cardiac events and coronary revascularization than those with normal MPI. Among the 823 subjects (54.5%) whose MPIs were classified as appropriate (779, 51.6%) or uncertain (44, 2.9%), an abnormal scan predicted a multifold increase in the rates of death (9.2% versus 2.6%; hazard ratio, 3.1; P=0.004), death or myocardial infarction (11.8% versus 3.3%; hazard ratio, 3.3; P=0.001), cardiac death or myocardial infarction (6.7% versus 1.7%; hazard ratio, 3.7; P=0.006), and revascularization (24.7% versus 2.7%; hazard ratio, 11.4; P<0.001). Among the 688 subjects (45.5%) with MPI classified as inappropriate, an abnormal MPI failed to predict major adverse cardiac events, although it was associated with a high revascularization rate. Furthermore, appropriate MPI use provided incremental prognostic value beyond myocardial perfusion and ejection fraction data. CONCLUSIONS: When performed for appropriate indications, SPECT-MPI continues to demonstrate high prognostic value. However, inappropriate use lacks effectiveness for risk stratification, further emphasizing the need for optimal patient selection for cardiac testing.

The value of SPECT/CT in localizing pain site and prediction of treatment response in patients with chronic low back pain.

In many circumstances, causing sites of low back pain (LBP) cannot be determined only by anatomical imaging. Combined functional and morphological imaging such as bone scan with single-photon emission computed tomography/computed tomography (SPECT/CT) may be helpful in identifying active lesions. The purpose of this study was to evaluate the usefulness of bone SPECT/CT in localizing the pain site and the treatment of chronic LBP. One hundred seventy-five patients suffering from chronic LBP who underwent SPECT/CT were included, retrospectively. All of the patients received multiple general treatments according to the symptoms, and some of them underwent additional target-specific treatment based on SPECT/CT. Numerical rating scale (NRS) pain score was used to assess the pain intensity. Of 175 patients, 127 showed good response to the given therapies, while the rest did not. Overall, 79.4% of patients with definite active lesions showed good response. Patients with mild active or no lesions on SPECT/CT had relatively lower response rate of 63.0%. Good response was observed by the treatment with the guidance of active lesions identified on SPECT/CT. SPECT/CT could be useful in identifying active lesions in patients with chronic LBP and guiding the clinicians to use adequate treatment.

Longitudinal trajectories of cognitive decline and cerebral blood flow abnormalities in octogenarian men with normal global cognition.

Aims: Cognitive and perfusion changes have been previously observed in older men with Mini Mental State Examination scores>24 points. We aimed to investigate time change in cognitive domains in a cohort of non-demented men between age 68 and 82, and how they are expressed in regional defects estimated by Cerebral Blood Flow (rCBF). Methods: 103 men at age 81 with MMSE scores >24 (mean 28.4 ± 1.7), no dementia or stroke, were examined with the same cognitive test battery at age 68 and age 81: Synonyms (SRB-1), Block design (SRB-3), Paired Associates, Digit Symbol Substitution and Benton Visual Retention test. rCBF was estimated using 99mTc-HMPAO SPECT at age 82. Results: Between ages 68 and 82 we observed a relative decline (Δ%) of cognitive test scores: SRB-3 and Benton tests, -33.7 % (SD 16,8) and -25.8 % (SD 23.9) respectively, followed by Digit Symbol test: -22,6 % (SD 15,6). The cluster of men (46 %) could be detected, grouped on the largest test score decline and highest overall test predictors' importance in decreasing order: Δ% SRB-3, Δ% Paired Associates, Δ% Digit Symbol, Δ% Benton VR and Δ% SRB-1. Compared to the cluster with stable cognitive functions, it expressed lower rCBF in frontal and parietal lobes, and in subcortical areas. Conclusion: Nearly half of the studied, community-dwelling cohort of non-demented, octogenarian men with MMSE > 24, had a combination of decreasing visuospatial ability and episodic memory during preceding years, expressed by widespread rCBF changes in fronto-subcortical areas.

123I-iomazenil single photon emission computed tomography visualizes recovery of neuronal integrity by bone marrow stromal cell therapy in rat infarct brain.

BACKGROUND AND PURPOSE: This study was aimed to assess whether (123)I-iomazenil (IMZ) single photon emission computed tomography can serially monitor the effects of bone marrow stromal cell (BMSC) transplantation on neuronal integrity in infarct brain of rats. METHODS: The BMSCs were harvested from green fluorescent protein-transgenic rats and were cultured. The rats were subjected to permanent middle cerebral artery occlusion. Their motor function was serially quantified throughout the experiments. The BMSCs or vehicle was stereotactically transplanted into the ipsilateral striatum at 7 days after the insult. Using small-animal single photon emission computed tomography/computed tomography apparatus, the (123)I-IMZ uptake was serially measured at 6 and 35 days after the insult. Finally, fluorescence immunohistochemistry was performed to evaluate the distribution of engrafted cells and their phenotypes. RESULTS: The distribution of (123)I-IMZ was markedly decreased in the ipsilateral neocortex at 6 days postischemia. The vehicle-transplanted animals did not show a significant change at 35 days postischemia. However, BMSC transplantation significantly improved the distribution of (123)I-IMZ in the peri-infarct neocortex as well as motor function. The engrafted BMSCs were densely distributed around cerebral infarct, and some of them expressed neuronal nuclear antigen and γ-aminobutyric acid type-A receptor. CONCLUSIONS: The present findings strongly suggest that the BMSCs may enhance functional recovery by improving the neuronal integrity in the peri-infarct area, when directly transplanted into the infarct brain at clinically relevant timing. (123)I-IMZ single photon emission computed tomography may be a promising modality to scientifically prove the beneficial effects of BMSC transplantation on the host brain in clinical situation.

Vall d'Hebron Risk Score II for myocardial infarction and cardiac death.

OBJECTIVES: The aim of this study was to create a new Vall d'Hebron Risk Score-II (VH-RS-II) for non-fatal myocardial infarction (MI) and/or cardiac death (CD), excluding patients with coronary revascularisation (CR) during the follow-up. METHODS: We analysed 5215 consecutive patients underwent gated single photon emission CT (SPECT); 2960 patients (age 64.2±11, male 58.1%) had no previous MI and/or CR, and 2255 patients (age 63.3±11, male 81.9%) had previous MI and/or CR. During a follow-up of 4.3±2.6 years, the cardiac event (MI and CD) was evaluated. This study was reviewed and approved by the ethics committee of our institution (number form trial register, PR(AG)168.2012). To obtain the predictor model, multivariate Cox regression analysis and multivariate logistic regression analysis were used. RS-VH-II was validated with 679 patients. RESULTS: In patients without previous MI and/or CR, age (HR: 1.01; p<0.001), diabetes (HR: 2.1, p=0.001), metabolic equivalent (METs) (HR: 0.89, p=0.038), ST segment depression (HR: 1.4, p=0.011), ejection fraction (EF) (HR: 0.97, p<0.001) and summed stress score (HR: 1.2, p<0.001) were the independent predictors of CE (C-statistic: 0.8). In patients with previous MI and/or CR, age (HR: 1.06, p<0.001), male (HR: 1.9, p=0.047), smoker (HR: 1.5, p=0.047), METs (HR: 0.8, p<0.001), ST segment depression (HR: 1.4, p=0.002), EF (HR: 0.96; p<0.001) and summed difference score (HR: 1.03, p=0.06) were the independent predictors of CE (C-statistic:0.8). CONCLUSION: The VH-RS-II obtained from different clinical exercise and gated SPECT variables allow the risk stratification for MI and CD in patients with or without previous MI and/or CR in due form.

Value of Thallium-201 SPECT and SPECT/CT Brain Imaging in Differentiating Malignant From Nonmalignant Lesions: A Comparative Case-Series Study With Pathologic and/or Clinical Correlation.

BACKGROUND: Thallium-201 single-photon emission computed tomography/computed tomography (SPECT/CT) brain scan is an imaging modality which can be done to differentiate between malignant and nonmalignant lesions among patients with nonconclusive findings on conventional neuroimaging. This study describes the results of thallium-201 SPECT/CT brain imaging and relate it to histopathologic and/or clinical findings and evaluate the value of thallium-201 SPECT/CT brain imaging in differentiating malignant from nonmalignant lesions. METHODS: This is a retrospective case series study of 10 patients with cerebral lesions who underwent thallium-201 SPECT/CT brain imaging in a hospital in the Philippines from 2010 to 2021. RESULTS: A total of 10 patients underwent thallium-201 SPECT/CT brain scan. Six had negative results while 4 had positive results. All of the patients who had positive results were found to have malignancy, whether recurrent or newly diagnosed. All of the patients with negative scan were found to have either an infectious and inflammatory disease and responded to treatment albeit in different degrees. Two of the 10 patients underwent biopsy whose results were consistent with the thallium-201 SPECT/CT brain scan results. CONCLUSION: Thallium-201 brain scan combined with SPECT and SPECT/CT has been demonstrated to be useful in distinguishing malignant from nonmalignant lesions and is more cost-effective versus other imaging techniques. The findings in this study support the role of thallium scintigraphy in the diagnosis of patients with brain lesions most significantly when there is a need to differentiate between a malignant and benign condition.

Randomised trial of stable chest pain investigation: 3-year clinical and quality of life results from CE-MARC 2.

AIMS: Guidelines for suspected cardiac chest pain have used historical risk stratification tools, advocating invasive coronary angiography (ICA) first-line in those at highest risk. We aimed to determine whether different strategies to manage suspected stable angina affected medium-term cardiovascular event rates and patient-reported quality of life (QoL) measures. METHODS: CE-MARC 2, a three-arm parallel group trial, randomised patients with suspected stable cardiac chest pain and a Duke Clinical pretest likelihood of coronary artery disease between 10% and 90%. Patients were randomised to either first-line cardiovascular magnetic resonance (CMR), single-photon emission computed tomography (SPECT) or the UK National Institute for Health and Care Excellence (NICE) CG95 (2010) guidelines-directed care. For the three arms, 1-year and 3-year first major adverse cardiovascular event (MACE) rates and QoL assessed by the Seattle Angina Questionnaire, Short Form 12 (V.12) Questionnaire and EuroQol-5 Dimension Questionnaire were recorded. RESULTS: 1202 patients were randomised to CMR (n=481), SPECT (n=481) and NICE (n=240). Forty-two patients (18 CMR, 18 SPECT, 6 NICE) experienced one or more MACEs. The percentage rates (95% CIs) of MACE in the CMR, SPECT and NICE groups at 3 years were 3.7% (2.4%, 5.8%), 3.7% (2.4%, 5.8%) and 2.1% (0.9%, 4.8%), respectively. QoL scores did not significantly differ across domains. CONCLUSION: Despite a fourfold increase in referrals for ICA, the NICE CG95 (2010) guidelines risk-stratified care strategy did not significantly reduce 3-year MACE or improve QoL, as compared with functional imaging with CMR or SPECT. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT01664858).

Crossed aphasia in a left-handed patient with non-fluent variant of primary progressive aphasia with left asymmetric brain SPECT.

Primary progressive aphasia is a clinical syndrome caused by neurodegeneration of areas and neural networks involved in language, usually in the left hemisphere. The term "crossed aphasia" denotes an acquired language dysfunction caused by a lesion in the ipsilateral hemisphere to the dominant hand. Objective: To describe a case of crossed aphasia in a 60-year-old left-handed patient with a non-fluent variant of primary progressive aphasia diagnosis (age of onset=52), evidenced by a left asymmetry on brain SPECT scan. Methods: Clinical and family history, the Edinburgh Handedness Inventory, Measurement of Functional Activities in Older Adults in the Community, the "Mini-Mental State Examination", the Trail Making Test, the Tower of London, and the Neuropsychological assessment for dementia, and neuroimaging studies were carried out. Results: Neuropsychological assessment showed severe cognitive impairment, especially regarding language. The magnetic resonance imaging showed important signs of cortico-subcortical atrophy, with predominance in the frontal and temporal lobes. The single-photon emission computed tomography scan showed moderate to severe hypoperfusion in the left cerebral hemisphere, including the hippocampus. Conclusion: We described a clinical case of crossed aphasia in a left-handed woman with a non-fluent variant of primary progressive aphasia with asymmetry on brain SPECT, mainly on the left, followed up for seven years.

A afasia progressiva primária é uma síndrome clínica causada por uma neurodegeneração de áreas e redes neurais envolvidas na linguagem, geralmente no hemisfério esquerdo. O termo "afasia cruzada" denota uma disfunção adquirida de linguagem causada por uma lesão no hemisfério ipsilateral da mão dominante. Objetivo: Relatamos um caso de afasia cruzada em uma paciente de 60 anos, canhota, com um quadro clínico de afasia progressiva primária variante não fluente (idade de início=52), evidenciada por assimetria no SPECT cerebral à esquerda. Métodos: Foram realizados para o diagnóstico do caso: história clínica e familiar, o Inventário de Dominância de Edinburgh, a Escala de Atividades Funcionais de Pfeffer, o Miniexame do Estado Mental, o Teste das Trilhas, o Teste da Torre de Londres, a Avaliação Neuropsicológica Adequada às Demências e exames de neuroimagem. Resultados: A avaliação neuropsicológica mostrou comprometimento cognitivo severo, principalmente sobre a linguagem; a ressonância magnética do crânio mostrou sinais de involução córtico-subcortical, com predominância nos lobos frontal e temporal e a cintilografia cerebral por emissão de fóton único mostrou hipoperfusão moderada a severa no hemisfério cerebral esquerdo, incluindo o hipocampo. Conclusão: Registramos um caso clínico de afasia cruzada em uma paciente canhota com afasia progressiva primária variante não fluente com assimetria no SPECT cerebral, principalmente à esquerda, seguida há sete anos.

Myocardial Flow Assessment After Heart Transplantation Using Dynamic Cadmium-Zinc-Telluride Single-Photon Emission Computed Tomography With 201Tl and 99mTc Tracers and Validated by 13N-NH3 Positron Emission Tomography.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is an obliterative and diffuse form of vasculopathy and is the most common cause of long-term cardiovascular mortality in heart transplant patients. This study aimed to investigate the diagnostic performance of 99mTc and 201Tl tracers in the assessment of CAV using cadmium-zinc-telluride (CZT) single-photon emission computed tomography (SPECT) for myocardial blood flow (MBF) and myocardial flow reserve (MFR) quantification, which was further validated using 13 N-NH3 positron emission tomography (PET). METHODS: Thirty-eight patients with prior heart transplantation who underwent CZT SPECT and 13 N-NH3 PET dynamic scans were included in this study. CZT SPECT with 99mTc-sestamibi was used in the first 19 patients and 201Tl-chloride for the remaining patients. To determine the diagnostic accuracy of angiographically defined moderate-to-severe CAV, the analysis included patients who underwent angiographic examinations within 1 year of their second scan. RESULTS: There were no significant differences in the patient characteristics between the 201Tl and 99mTc tracer groups. Both 201Tl and 99mTc CZT SPECT-derived stress MBF and MFR values globally and in 3 coronary territories showed good correlations with 13 N-NH3 PET. The 201Tl and 99mTc cohorts did not differ significantly in the correlation coefficients of CZT SPECT versus PET for MBF and MFR, except for stress MBF (201Tl:0.95 versus 99mTc:0.80, P=0.03). 201Tl and 99mTc CZT SPECT were satisfactory for detecting PET MFR <2.0 (201Tl area under the curve, 0.92 [0.71-0.99], 99mTc area under the curve, 0.87 [0.64-0.97]) and angiographically defined moderate-to-severe CAV, and CZT SPECT results were comparable to that of 13 N-NH3 PET (CZT area under the curve, 0.90 [0.70-0.99], PET area under the curve, 0.86 [0.64-0.97]). CONCLUSIONS: This small study suggests that CZT SPECT using 201Tl and 99mTc tracers showed comparable MBF and MFR, and the results correlated well with those of 13 N-NH3 PET. Hence, CZT SPECT with 201Tl or 99mTc tracers can be used to detect moderate-to-severe CAV in patients with prior heart transplantation. However, validation using larger studies is warranted.

Accuracy and Reproducibility of Myocardial Blood Flow Quantification by Single Photon Emission Computed Tomography Imaging in Patients With Known or Suspected Coronary Artery Disease.

BACKGROUND: Single photon emission computed tomography (SPECT) has limited ability to identify multivessel and microvascular coronary artery disease. Gamma cameras with cadmium zinc telluride detectors allow the quantification of absolute myocardial blood flow (MBF) and myocardial flow reserve (MFR). However, evidence of its accuracy is limited, and of its reproducibility is lacking. We aimed to validate 99mTc-sestamibi SPECT MBF and MFR using standard and spline-fitted reconstruction algorithms compared with 13N-ammonia positron emission tomography in a cohort of patients with known or suspected coronary artery disease and to evaluate the reproducibility of this technique. METHODS: Accuracy was assessed in 34 participants who underwent dynamic 99mTc-sestamibi SPECT and 13N-ammonia positron emission tomography and reproducibility in 14 participants who underwent 2 99mTc-sestamibi SPECT studies, all within 2 weeks. A rest/pharmacological stress single-day SPECT protocol was performed. SPECT images were reconstructed using a standard ordered subset expectation maximization (OSEM) algorithm with (N=21) and without (N=30) application of spline fitting. SPECT MBF was quantified using a net retention kinetic model' and MFR was derived as the stress/rest MBF ratio. RESULTS: SPECT global MBF with splines showed good correlation with 13N-ammonia positron emission tomography (r=0.81, P<0.001) and MFR estimates (r=0.74, P<0.001). Correlations were substantially weaker for standard reconstruction without splines (r=0.61, P<0.001 and r=0.34, P=0.07, for MBF and MFR, respectively). Reproducibility of global MBF estimates with splines in paired SPECT scans was good (r=0.77, P<0.001), while ordered subset expectation maximization without splines led to decreased MBF (r=0.68, P<0.001) and MFR correlations (r=0.33, P=0.3). There were no significant differences in MBF or MFR between the 2 reproducibility scans independently of the reconstruction algorithm (P>0.05 for all). CONCLUSIONS: MBF and MFR quantification using 99mTc-sestamibi cadmium zinc telluride SPECT with spatiotemporal spline fitting improved the correlation with 13N-ammonia positron emission tomography flow estimates and test/retest reproducibility. The use of splines may represent an important step toward the standardization of SPECT flow estimation.

Imaging Characteristics of Brain SPECT, PET, and MRI in Neurosyphilis.

The incidence of neurosyphilis has declined since effective penicillin therapy against Treponema pallidum was introduced. However, the diagnosis of neurosyphilis early in the disease course is very important in order to select appropriate antibiotic therapy. We report brain MRI, SPECT with Tc-99m ECD, and PET with F-18 FDG findings before antibiotic therapy in a neurosyphilis patient with neurological symptoms. The cerebral cortices showed hypoperfusion with a patchy distribution on SPECT and foci with high signal intensity on MRI, suggesting ischemia. Brain PET showed areas with hypometabolism in the temporoparietal lobes bilaterally.