Accuracy of Choline PET/CT vs. Tc 99m Sestamibi SPECT/CT parathyroid imaging in comparison to histopathology in the diagnosis of parathyroid adenoma : A meta-analysis

Introduction@#In the advent of the recently accepted use of Choline in parathyroid PET/CT, we aimed to assess its accuracy in diagnosing parathyroid adenomas in comparison to the Tc 99m Sestamibi SPECT/CT parathyroid imaging, with histopathology as the reference standard.@*Objective@#To determine the diagnostic accuracy of Choline PET/CT in comparison to Tc 99m Sestamibi parathyroid imaging in detecting parathyroid adenomas, with histopathology as the reference standard. @*Methods@#Cross-sectional studies from 2014 to 2019 were identified through MEDLINE, Pubmed, clinicaltrials.gov, and Google scholar. Our literature search yielded 13 articles, of which only 3 met the set inclusion and exclusion criteria.@*Results@#Three published cross-sectional studies were included with a total of population of 157 patients. Choline PET/CT was found to have a pooled sensitivity of 0.99 (0.96 - 1.00), pooled specificity of 0.45 (0.17 - 0.77), positive likelihood ratio of 1.79 (1.1 – 2.9), negative likelihood ratio of 0.03 (0.0 – 0.1), positive predictive value of 96.0% (93.4 - 97.7%) and negative predictive value of 83.3% (39.0 - 97.6%), estimated with 95% CI. Tc 99m Sestamibi SPECT/CT parathyroid imaging had a pooled sensitivity of 0.77 (0.70-0.84), pooled specificity of 0.45 (0.17 - 0.77), positive likelihood ratio of 1.43 (0.8–2.4), negative likelihood ratio of 0.49 (0.2–1.4), positive predictive value of 96.0% (93.4-97.7%) and negative predictive value of 83.3% (39.0-97.6%), estimated with 95% CI@*Conclusion@#Choline PET/CT showed superior sensitivity, negative predictive value and negative likelihood ratio over Tc 99m Sestamibi SPECT/CT parathyroid imaging. The measured specificities, positive predictive values and positive likelihood ratios of both modalities were found to be similar.

Added Value of Subtraction SPECT/CT in Dual-Isotope Parathyroid Scintigraphy.

BACKGROUND: Adding subtraction single-photon emission computed tomography/computed tomography (SPECT/CT) to dual isotope (I-123 and Tc-99m-sestamibi) subtraction parathyroid scintigraphy is not widely implemented. We aimed to assess the added value of dual isotope subtraction SPECT/CT over single isotope SPECT/CT as an adjunct to dual isotope planar pinhole subtraction scintigraphy. METHODS: Parathyroid scintigraphies from 106 patients with an estimated total of 415 parathyroid glands who (1) were diagnosed with primary hyperparathyroidism, (2) underwent dual isotope subtraction scintigraphy in the Department of Nuclear Medicine, Gentofte Hospital, Denmark throughout 2017 and (3) underwent subsequent parathyroidectomy, were included. The original dual isotope planar pinhole subtraction plus dual isotope subtraction SPECT/CT (dual/dual method) exams were retrospectively re-evaluated using only Tc-99m-sestamibi SPECT/CT (dual/single method). Statistics were calculated per parathyroid. Surgical results confirmed by pathology served as reference standard. RESULTS: The dual/dual method had higher sensitivity than the dual/single method (82% (95%CI 74%-88%) vs. 69% (95%CI 60%-77%)) while specificity, positive and negative predictive values (PPV and NPV) were similar (specificity 96% vs. 93%, PPV's 87% vs. 82% and NPV's 89% vs. 93%). Reader confidence was higher when employing the dual/dual method (p = 0.001). CONCLUSIONS: The dual/dual method can be considered superior to the dual/single method in the preoperative imaging in primary hyperparathyroidism.

Ectopic Intrathymic Parathyroid adenoma demonstrated on Tc-99m Sestamibi SPECT-CT.

Intrathymic parathyroid adenoma is a rare cause of primary hyperparathyroidism. In this case, Tc-99m Sestamibi SPECT-CT successfully localized abnormal tracer uptake in the mediastinum with corresponding low density lesion on CT images suggestive of mediastinal parathyroid adenoma which late on confirmed on histopathology. After the median sternotomy a large intrathymic parathyroid adenoma was identified and excised. With the help of gamma probe the surgeons detect the lesion early and with more confidence as well as reducing the total operation time. Tc-99m Sestamibi SPECT-CT scintigraphy and gamma probe localization is recommended for preoperative and intra operative localization of ectopic parathyroid adenomas.

Prognostic value of late gadolinium enhancement in cardiovascular magnetic resonance imaging after acute ST-elevation myocardial infarction in comparison with single-photon emission tomography using Tc99m-Sestamibi.

BACKGROUND: Infarct size is an important predictor of cardiac risk after acute myocardial infarction. The established modality for its assessment is Tc99m-Sestamibi Single-photon emission computed tomography (SPECT). In recent years, data are emerging demonstrating that scar size as assessed by late gadolinium enhancement in cardiovascular magnetic resonance imaging (CMR) as well as the presence of microvascular obstruction (MO) may also provide prognostic information, however, so far no direct comparisons of both modalities have been reported. METHODS: We retrospectively analysed patients (n = 281) with acute ST-elevation myocardial infarction and primary angioplasty who underwent Tc99m-Sestamibi-SPECT and CMR on a 1.5 T scanner at a median of 4.3 (IQR: 3.7-5.1) and 4.9 (IQR: 4.1-5.9) days after the acute event, respectively. The primary endpoint of the study was a composite of all-cause mortality, recurrent myocardial infarction and congestive heart failure requiring hospitalization. RESULTS: During a median follow-up of 3.0 (IQR: 2.0-4.5) years, 24 events occurred. The best predictor was MO (P < 0.0001), followed by infarct size by CMR (P = 0.0043) and infarct size by SPECT (P = 0.012) (all P-values corrected for clinical risk). In a multivariate model including clinical and periprocedural parameters, MO remained the only significant predictor in addition to clinical risk. CONCLUSIONS: The extent of MO as determined by CMR has an excellent prognostic value in predicting cardiac events following acute myocardial infarction and may be used as an alternative to infarct size assessment by Tc99m-Sestamibi-SPECT.

Post-stress Measurements of Left Ventricular Function With Gated Perfusion SPECT: Comparison with Resting Measurements by using Exercise and Adenosine Stress

BACKGROUND AND OBJECTIVES: This study was designed to investigate the relationship between myocardial perfusion defect in single photon emission tomography(SPECT) and the difference in left ventricular functional parameters obtained after stress and at rest. MATERIALS AND METHODS: Eighty five patients known to have coronary artery disease (CAD) or suspected to have CAD underwent gated Tc-99m sestamibi SPECT using one or separate day rest/stress protocol. We compared post-stress left ventricular ejection fraction (LVEF-s) with that at rest (LVEF-r) in gated myocardial SPECT. We considered myocardial stunning was developed when LVEF was >5% lower than that at rest. METHODS: Forty one (48%) patients demonstrated reversible or irreversible perfusion defects in gated perfusion SPECT (group 1). Forty four (52%) patients demonstrated normal perfusion status (group 2). In group 1, LVEF-s was significantly lower than that at rest([mean+/-SD] 46+/-15.5 vs 48+/-16.0 respectively, p5% lower than LVEF-r. CONCLUSION: The LVEF obtained after stress with gated SPECT may not reflect true resting values. We recommend gated myocardial perfusion SPECT should be performed also at rest especially in patients with myocardial perfusion defects.

Assessments of myocardial perfusion in human using stress intravenous PESDA myocardial contrast echocardiography and Pulse Inversion Harmonic Imaging: A Comparison study with Tc-99m sestamibi SPECT

OBJECTIVE: The object of this study was to assess the accuracy of dipyridamole stress intravenous (IV) myocardial contrast echocardiography (MCE) using pulse inversion harmonic imaging and PESDA in the detection of perfusion defect in the patients with coronary artery disease in comparison with dipyridamole stress Tc-99m sestamibi SPECT. METHODS: Total 46 patients (29 males, mean age 64 years old) were consecutively enrolled. Patients with prior myocardial infarction were excluded. MCE and Tc-99m sestamibi SPECT were performed at the same day during rest and after 0.56 or 0.84mg/Kg dipyridamole infusion. Continuous IV infusion of PESDA (2-5 mL/min) was administered while obtaining triggered (1:1) end-systolic apical 2, 4 chamber and long axis views. Tc-99m sestamibi was injected 3 minutes after dipyridamole. Tc-99m sestamibi SPECT images were obtained one hour later. Coronary angiography was followed within two days in all patients. Tc-99m sestamibi SPECT images were matched to the sixteen segments of left ventricle according to American Society of Echocardiography for segmental comparison. Both images were analyzed visually. Results Using coronary angiography as the standard, MCE showed overall sensitivity of 70.7%, specificity of 95.8%, positive predictive value (PPV) of 87.8% and negative predictive value (NPV) of 88.5% in the detection of coronary atherosclerosis (70% stenosis). Tc-99m sestamibi SPECT showed sensitivity of 75.6%, specificity of 98.9%, PPV of 96.8% and NPV of 90.6%. The overall concordance rate between MCE and Tc-99m sestamibi SPECT for the detection of perfusion defects was 86.9% (Cohen's kappa value 0.63) according to the coronary territory and 86.8% (Cohen's kappa value 0.55) according to segmental analysis. CONCLUSION: Dipyridamole stress IV MCE using pulse inversion harmonic imaging and PESDA is feasible and comparable to Tc-99m sestamibi SPECT in identifying significant coronary stenosis and inducible myocardial perfusion defects in the patients with coronary artery disease. MCE using pulse inversion harmonic imaging seems to be a promising modality for assessing myocardial perfusion in the patients with suspected coronary artery disease.