Adrenal Masses: Characterization with in Vivo Proton MR Spectroscopy—Initial Experience

• DOI: 10.1148/radiol.2453061854
• Publication Date: 2008-01-05T00:54:37Z
• Authors: Juliano F. Faria; Suzan M. Goldman; Jacob Szejnfeld; Homero Melo; Cláudio Kater; Philip Kenney; Martha P. Huayllas; Guilherme Demarchi; Viviane V. Francisco; Cássio Andreoni; Miguel Srougi; Valdemar Ortiz; Nitamar Abdalla
• Keywords: Choline; Creatine

Purpose: To prospectively determine the accuracy of in vivo proton (1H) magnetic resonance (MR) spectroscopy distinguishing adrenal adenomas, pheochromocytomas, adrenocortical carcinomas, and metastases, with histologic or computed tomographic findings follow-up data as reference standards. Materials Methods: This study was approved by institutional ethics committee, informed consent obtained. Sixty consecutive patients (24 male 36 female patients; mean age, 53 years) harboring tumors larger than 2 cm diameter (mean diameter, 4.6 ± 3.4 [standard deviation]) entered were examined a 1.5-T MR imaging system point-resolved multivoxel 1H spectroscopy. Thirty-eight had adenomas; 10, pheochromocytomas; five, carcinomas; seven, metastases. Amplitude values for choline, creatine, lipid, metabolite peak at precession frequency 4.0–4.3 ppm measured. Metabolite ratios (choline-creatine, choline-lipid, lipid-creatine, ppm/creatine) cutoff (obtained using receiver operating characteristic analyses) obtained compared each type mass, which identified previously on basis clinical, hormonal, pathologic evidence. Results evaluated χ2 Student t tests. Significance inferred P < .05. Results: Cutoff 1.20 choline-creatine ratio (92% sensitivity, 96% specificity; .01), 0.38 choline-lipid 90% 2.10 lipid-creatine (45% 100% specificity) enabled adenomas pheochromocytomas to be distinguished from carcinomas A ppm/creatine greater 1.50 distinction metastases (87% 98% .01). The best comparing ratios. Conclusion: can used characterize masses spectral benign © RSNA, 2007