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We assessed the prognostic value of structural abnormalities and coronary vasodilator function in diabetic patients referred to a PET/CT for suspected coronary artery disease (CAD).We studied 451 diabetics and 451 nondiabetics without overt CAD and normal myocardial perfusion. Myocardial blood flow (MBF) was computed from the dynamic rest and stress imaging. Myocardial flow reserve (MFR) was defined as ratio of hyperemic to baseline MBF and was considered reduced when 2.During a mean follow-up of 44 months 33 events occurred. Annualized event rate (AER) was higher in diabetic than nondiabetic patients (1.4% vs 0.3%, P .001). Diabetic patients with reduced MFR had higher AER compared to those with preserved MFR (3.3% vs 0.4%, P .001). At Cox analysis, age, BMI and reduced MFR were independent predictors of events in diabetic patients. Patients with diabetes and reduced MFR had lower event-free survival compared to nondiabetic patients and MFR 2 (P .001). Event-free survival was similar in patients with diabetes and normal MFR and those without diabetes and reduced MFR.Diabetic patients with reduced MFR had higher AER and lower event-free survival compared to those with preserved MFR and to nondiabetic patients.Se evaluó el valor pronóstico de las alteraciones estructurales y la función vasodilatadora coronaria en pacientes diabéticos remitidos a PET/CT por sospecha de enfermedad arterial coronaria (EAC). MéTODOS: Se estudiaron a 451 diabéticos y 451 no diabéticos sin EAC manifiesta y perfusión miocárdica normal. Se calculó el flujo sanguíneo miocárdico (MBF) a partir de las imágenes dinámicas en reposo y estrés. La reserva de flujo miocárdico (MFR) se definió como la relación entre la MBF en hiperemia entre el basal y se consideró reducida al ser2.Durante un seguimiento promedio de 44 meses ocurrieron 33 eventos. La tasa anual de eventos (TAE) fue mayor en los pacientes diabéticos que en los no diabéticos (1.4% frente a 0.3%, P.001). Los pacientes diabéticos con MFR reducido tuvieron una TAE más alta en comparación con aquellos con MFR preservado (3.3% vs 0.4%, P. 001). En el análisis de Cox, la edad, el IMC y el MFR reducido fueron predictores independientes de eventos en pacientes diabéticos. Los pacientes con diabetes y MFR reducido tuvieron una supervivencia libre de eventos más baja en comparación con los pacientes no diabéticos y MFR2 (P. 001). La supervivencia libre de eventos fue similar en pacientes con diabetes y MFR normal y aquellos sin diabetes y MFR reducido.Los pacientes diabéticos con MFR reducido tuvieron una mayor TAE y una menor supervivencia libre de eventos en comparación con aquellos con MFR conservado y con los pacientes no diabéticos.背景:Nous avons évalué la valeur pronostique des anomalies structurelles et de la vasodilatation coronaire chez les patients diabétiques qui nous ont été envoyé pour un examen TEP/TDM pour suspicion de maladie artérielle coronaire (MAC). MéTHODES: Nous avons étudié 451 diabétiques et 451 non-diabétiques sans MAC manifeste et avec une perfusion myocardique normale. Le débit sanguin myocardique (DSM) a été calculé sur bases des images TEP/TDM de repos et de stress. La réserve de perfusion myocardique (RPM) a été définie comme le rapport entre l’hyperémie myocardique et la perfusion myocardique de base et a été considérée comme réduite avec un rapport inferieur à 2. RéSULTATS: Au cours d’un suivi moyen de 44 mois, 33 événements cardiaques ont été enregistrés. Le nombre d’événements cardiaques annualisés (ECA) s’est avéré plus élevé chez les patients diabétiques que chez les patients non diabétiques (1,4% vs 0,3%, P0,001). Les patients diabétiques dont la RPM était réduite ont montré un nombre d’ECA plus élevé que ceux dont la RPM était préservée (3,3% vs 0,4%, P0,001). L’analyse statistique basée sur la méthode Cox a montré que, l’âge, l’IMC et la réduction de la RPM sont des paramètres indépendants chez les patients diabétiques. Les patients atteints de diabète avec une réduction de leur RPM ont eu une survie avec un nombre plus élevés d’événements cardiaques par rapport aux patients non diabétiques avec une RPM inferieure à 2 (P.001). La survie sans événements cardiaques s’est révélée similaire chez les patients atteints de diabète avec une RPM normale et ceux sans diabète avec une RPM réduite.Dans cette étude, les patients diabétiques avec un MFR réduit ont eu une survie entachée d’un nombre plus important d’événements cardiaques par rapport aux diabétiques avec une réserve de perfusion myocardique préservée et aux patients non diabétiques.

We measured myocardial blood flow (MBF) and perfusion reserve (MPR) by dynamic CZT-SPECT andTwenty-five patients with available coronary angiography data underwentCZT-SPECT yielded similar baseline MBF, but higher hyperemic MBF and MPR values compared to PET. There was a modest correlation between the two methods for MPR (r = 0.56, P.01). MPR by CZT-SPECT showed a good ability in identify a reduced MPR by PET, with an area under the curve of 0.85. A MPR cut-off of 2.5 was identified by CZT-SPECT for detection of abnormal MPR by PET, with a sensitivity, specificity and accuracy of 86%, 73% and 80%. The area under the curve for the identification of obstructive CAD by regional MPR were 0.83 for CZT-SPECT and 0.84 for PET (P = .90). At CZT-SPECT, a regional MPR of 2.1 provided the best trade-off between sensitivity and specificity for identifying obstructive CAD. Diagnostic accuracy of CZT-SPECT and PET using respective cut-off values was comparable (P = .62).Hyperemic MBF and MPR values obtained by CZT-SPECT are higher than those measured by

Cardiac imaging with positron emission tomography/computed tomography (PET/CT) allows measurement of coronary artery calcium (CAC), stress-induced myocardial ischemia and myocardial perfusion reserve (MPR). We evaluated the prognostic role of the combined assessment of regional CAC score, ischemic total perfusion defect (ITPD) and MPR in predicting lesion-related outcome in patients with suspected coronary artery disease (CAD).We studied 206 patients with suspected CAD referred toCompared to vessels without event, those with event showed higher CAC score and ITPD, and lower hyperemic myocardial blood flow and MPR (all p 0.001). At Cox regression multivariable analysis, significant CAD (≥50% stenosis) (p 0.001), CAC score ≥ 300 (p 0.01) and MPR2 (p 0.01) were independent predictors of events. The decision trees analysis for the identification of events produced five terminal nodes. The initial split was on CAC score values. For vessels with CAC300 and MPR ≥2, no further split was performed, while vessels with CAC300 and MPR2 were further stratified by ITPD. For vessels with CAC ≥300 a further stratification was performed only by MPR. The worst prognosis was observed in vessels with CAC ≥300 and MPR2 and in vessels with CAC300, MPR2 and ITPD ≥5%.The combination of CAC score and MPR is useful to predict the lesion-related outcome in the presence of significant CAD.

Cardiac imaging with PET/CT allows measurement of coronary artery calcium (CAC), myocardial perfusion and coronary vascular function. We investigated whether the combined assessment of regional CAC score, ischemic total perfusion deficit (ITPD) and quantitative coronary vascular function would further improve the diagnostic accuracy of PET/CT in predicting obstructive coronary artery disease (CAD).We analyzed 113 patients with suspected CAD referred toVessels with obstructive CAD (71 vessels) had higher ITPD (4.6 ± 6.2 vs. 0.6 ± 1.3) and lower hyperemic MBF (1.01 ± 0.5 vs. 1.75 ± 0.6 ml/min/g) and CFR (1.56 ± 0.6 vs. 2.38 ± 0.7; all p 0.001) than those without. In prediction of per-vessel CAD, the AUCs for the models including CAC/ITPD/hyperemic MBF (0.869) and CAC/ITPD/CFR (0.875) were higher (both p 0.01) than for the model including CAC/ITPD (0.790). Compared with CAC/ITPD, continuous net reclassification improvement was 0.69 (95% bootstrap confidence interval, CI, 0.365-1.088) for the CAC/ITPD/hyperemic MBF model and 0.99 (95% bootstrap CI 0.64-1.26) for the CAC/ITPD/CFR model.Hyperemic MBF and CFR provide incremental information about the presence of CAD over CAC score and perfusion imaging parameters. The combined use of CAC, myocardial perfusion imaging and quantitative coronary vascular function in may help predict more accurately the presence of obstructive CAD.

AIM: In patients with non-hypersecreting adrenal masses, tumor characterization is clinically relevant to establish the appropriate treatment planning. The aim of this study was to comparatively characterize such adrenal lesions using MR and radionuclide techniques. METHODS: Thirty patients with non-hypersecreting unilateral adrenal tumors underwent both MR and adrenal scintigraphy. MR was performed using SE T1- (pre- and post-gadolinium DTPA) and T2-weighted images as well as in- and out-phase chemical-shift imaging (CSI). MR qualitative and quantitative (signal intensity ratios) evaluation was performed. Radionuclide studies consisted of iodine-131 nor-cholesterol (n=20), iodine-131 MIBG (n=15) and fluorine-18 FDG PET (n=11) scans. Histology (n=16), biopsy (n=3) or clinical-imaging follow-up (n=11) demomstrated 13 adenomas, 3 cysts, 2 myelolipomas, 4 pheochromocytomas (pheos), 4 carcinomas, 1 sarcoma and 3 metastases. Comparative imaging analysis was focused on adenomas, pheos and malignant tumors. RESULTS: Qualitative MR evaluation showed: signal T2-hyperintensity in 46% of adenomas and in 100% of pheos and malignant tumors, no gadolinium enhancement in 92% of adenomas and definite signal intensity loss on CSI in 100% of such tumor lesions, gadolinium enhancement in 100% of pheos and in 63% of malignancies and no absolute change of signal intensity on CSI in 100% of both pheos and malignancies. Quantitative MR analysis demonstrated: significantly higher signal T2-hyperintensity of pheos compared to adenomas and malignancies as well as significantly higher enhancement after gadolinium in pheos compared to adenomas and malignancies (p

The aim of this study was to evaluate the role of radionuclide imaging in the characterization of nonhypersecreting adrenal masses.A total of 54 patients (19 men, 35 women; mean age, 50 +/- 16 y) with nonhypersecreting unilateral adrenal tumors that had been originally detected on CT or MRI underwent adrenal scintigraphy using different radiotracers. None of the patients showed specific symptoms of adrenal hypersecretion. Screening tests for excess cortical and medullary products showed normal adrenal hormone levels. Radionuclide studies (n = 73) included (131)I-norcholesterol (n = 24), (131)I-metaiodobenzylguanidine (MIBG) (n = 23), and (18)F-FDG PET (n = 26) scans.Histology after surgery (n = 31) or adrenal biopsy (n = 23) was obtained. Adrenal lesions were represented by 19 adenomas, 4 cysts, 1 myelolipoma, 1 neurinoma, 2 ganglioneuromas, 5 pheochromocytomas, 4 pseudotumors, 6 carcinomas, 2 sarcomas, and 10 metastases (size range, 1.5- to 5-cm diameter; mean, 4.9 +/- 3.1 cm). For norcholesterol imaging, diagnostic sensitivity, specificity, and accuracy were 100%, 71%, and 92%, respectively; the positive predictive value (PPV) of the norcholesterol scan to characterize an adrenal mass as an adenoma was 89%, whereas the corresponding negative predictive value (NPV) to rule out this type of tumor was 100%. For MIBG imaging, diagnostic sensitivity, specificity, and accuracy were 100%, 94%, and 96%, respectively; the PPV of the MIBG scan to characterize an adrenal mass as a medullary chromaffin tissue tumor was 83%, whereas the corresponding NPV to rule out this type of tumor was 100%. For FDG PET, diagnostic sensitivity, specificity, and accuracy were 100%, 100%, and 100%, respectively; the PPV of FDG PET to characterize an adrenal mass as a malignant tumor was 100%, whereas the corresponding NPV to rule it out was 100%. Furthermore, in 7 patients with malignant adrenal tumors, FDG whole-body scanning revealed extra-adrenal tumor sites (n = 29), allowing an accurate diagnosis of the disease's stage using a single-imaging technique.In patients with nonhypersecreting adrenal masses, radionuclide adrenal imaging, using specific radiopharmaceuticals such as norcholesterol, MIBG, and FDG, may provide significant functional information for tissue characterization. Norcholesterol and MIBG scans are able to detect benign tumors such as adenoma and pheochromocytoma, respectively. Conversely, FDG PET allows for recognition of malignant adrenal lesions. Therefore, adrenal scintigraphy is recommended for tumor diagnosis and, hence, for appropriate treatment planning, particularly when CT or MRI findings are inconclusive for lesion characterization.

Technetium-99m-methylene diphosphonate (MDP) uptake within breast lesions was investigated during routine presurgical bone scintigraphy in a cohort of women at high risk for cancer who were candidates for surgery or excisional biopsy. The aim was twofold: (a) to demonstrate positive 99mTc-MDP uptake in primary breast cancer and (b) to differentiate malignant from benign lesions.Anterior and oblique lateral views of the breasts were acquired 0-4 min, 10-20 min and 2 hr after intravenous injection of 740 MBq of 99mTc-MDP in 200 women with elevated suspicion or proven diagnosis of breast cancer (Group 1) and in 80 women with other solid tumor types (Group 2).Physical examination and mammography revealed breast abnormalities in all Group 1 subjects. The mammographic findings were definitely positive for carcinoma in 120 patients, highly suspicious in 27 and indeterminate in 53. Breast cancer was later histologically diagnosed in 172 women (86%) and benign disease found in 28 women (14%). Of these patients, 158 (92%) showed focal uptake of 99mTc-MDP in the images collected 10-20 min after injection. This was found to be the best timing for imaging, with tumor-to-background ratios as high as 4.3 (mean +/- s.d. = 3.8 +/- 0.4). Two hr after injection, only 61 of the 158 (38%) malignant lesions were clearly detectable.Technetium-99m-MDP is concentrated by primary breast carcinoma 10-20 min after injection, enabling successful external gamma imaging. Scintimammography with 99mTc-MDP is an accurate test that differentiates malignant from benign breast lesions, particularly in patients with indeterminate mammograms.