PT  - JOURNAL ARTICLE
AU  - Felix Nensa
AU  - Ercan Tezgah
AU  - Thorsten D. Poeppel
AU  - Christoph J. Jensen
AU  - Juliane Schelhorn
AU  - Jens Köhler
AU  - Philipp Heusch
AU  - Oliver Bruder
AU  - Thomas Schlosser
AU  - Kai Nassenstein
TI  - Integrated <sup>18</sup>F-FDG PET/MR Imaging in the Assessment of Cardiac Masses: A Pilot Study
AID  - 10.2967/jnumed.114.147744
DP  - 2015 Feb 01
TA  - Journal of Nuclear Medicine
PG  - 255--260
VI  - 56
IP  - 2
4099  - http://jnm.snmjournals.org/content/56/2/255.short
4100  - http://jnm.snmjournals.org/content/56/2/255.full
SO  - J Nucl Med2015 Feb 01; 56
AB  - The objective of the present study was to evaluate whether integrated 18F-FDG PET/MR imaging could improve the diagnostic workup in patients with cardiac masses. Methods: Twenty patients were prospectively assessed using integrated cardiac 18F-FDG PET/MR imaging: 16 patients with cardiac masses of unknown identity and 4 patients with cardiac sarcoma after surgical therapy. All scans were obtained on an integrated 3-T PET/MR device. The MR protocol consisted of half Fourier acquisition single-shot turbo spin-echo sequence, cine, and T2-weighted images as well as T1-weighted images before and after injection of gadobutrol. PET data were acquired simultaneously with the MR scan after injection of 199 ± 58 MBq of 18F-FDG. Patients were prepared with a high-fat, low-carbohydrate diet in a period of 24 h before the examination, and 50 IU/kg of unfractionated heparin were administered intravenously 15 min before 18F-FDG injection. Results: Cardiac masses were diagnosed as follows: metastases, 3; direct tumor infiltration via pulmonary vein, 1; local relapse of primary sarcoma after surgery, 2; Burkitt lymphoma, 1; scar/patch tissue after surgery of primary sarcoma, 2; myxoma, 4; fibroelastoma, 1; caseous calcification of mitral annulus, 3; and thrombus, 3. The maximum standardized uptake value (SUVmax) in malignant lesions was significantly higher than in nonmalignant cases (13.2 ± 6.2 vs. 2.3 ± 1.2, P = 0.0004). When a threshold of 5.2 or greater was used, SUVmax was found to yield 100% sensitivity and 92% specificity for the differentiation between malignant and nonmalignant cases. T2-weighted hyperintensity and contrast enhancement both yielded 100% sensitivity but a weak specificity of 54% and 46%, respectively. Morphologic tumor features as assessed by cine MR imaging yielded 86% sensitivity and 92% specificity. Consent interpretation using all available MR features yielded 100% sensitivity and 92% specificity. A Boolean ‘AND’ combination of an SUVmax of 5.2 or greater with consent MR image interpretation improved sensitivity and specificity to 100%. Conclusion: In selected patients, 18F-FDG PET/MR imaging can improve the noninvasive diagnosis and follow-up of cardiac masses.