OBJECTIVE: To report an experiment involving the introduction of a protocol utilizing commercially available three-dimensional 1H magnetic resonance spectroscopy imaging (3D 1H MRSI) method in patients diagnosed with prostatic tumors under suspicion of neoplasm. MATERIALS AND METHODS: Forty-one patients in the age range between 51 and 80 years (mean, 67 years) were prospectively evaluated. The patients were divided into two groups: patients with one or more biopsies negative for cancer and high specific-prostatic antigen levels (group A), and patients with cancer confirmed by biopsy (group B). The determination of the target-area (group A) or the known cancer extent (group B) was based on magnetic resonance imaging and MRSI studies. RESULTS: The specificity of MRSI in the diagnosis of prostate cancer was lower than the specificity reported in the literature (about 47%). On the other hand, for tumor staging, it corresponded to the specificity reported in the literature. CONCLUSION: The introduction and standardization of 3D 1H MRSI has allowed the obtention of a presumable diagnosis of prostate cancer, by a combined analysis of magnetic resonance imaging and metabolic data from 3D 1H MRSI.

Keywords: Magnetic resonance spectroscopy imaging, Prostate, Prostatic neoplasm

OBJECTIVE: To evaluate a protocol for two-dimensional (2D) hydrogen proton (1H) magnetic resonance spectroscopy (MRS) (Siemens Medical Systems; Erlangen, Germany) in the detection of adrenal nodules and differentiation between benign and malignant masses (adenomas, pheochromocytomas, carcinomas and metastases). MATERIALS AND METHODS: A total of 118 patients (36 men; 82 women) (mean age: 57.3 ± 13.3 years) presenting with 138 adrenal nodules/masses were prospectively assessed. A multivoxel system was utilized with a 2D point-resolved spectroscopy/chemical shift imaging sequence. The following ratios were calculated: choline (Cho)/creatine (Cr), 4.0–4.3/Cr, lipid (Lip)/Cr, Cho/Lip and lactate (Lac)/Cr. RESULTS: 2D-1H-MRS was successful in 123 (89.13%) lesions. Sensitivity and specificity values observed for the ratios and cutoff points were the following: Cho/Cr > 1.2, 100% sensitivity, 98.2% specificity (differences between adenomas/pheochromocytomas and carcinomas/metastases); 4.0–4.3 ppm/Cr > 1.5, 92.3% sensitivity, 96.9% specificity (differences between carcinomas/pheochromocytomas and adenomas/metastases); Lac/Cr < –7.449, 90.9% sensitivity and 77.8% specificity (differences between pheochromocytomas and carcinomas/adenomas). CONCLUSION: Information provided by 2D-1H-MRS were effective and allowed for the differentiation between adrenal masses and nodules in most cases of lesions with > 1.0 cm in diameter.

Keywords: Adrenal gland; Magnetic resonance imaging; Spectroscopy.

OBJECTIVE: To investigate the advantages of using modified signal intensity measurements on chemical shift imaging alone or in conjunction with proton magnetic resonance spectroscopy in the differential diagnosis of adrenal adenomas. MATERIALS AND METHODS: This was a prospective study involving 97 patients with adrenal nodules or masses. The signal intensity index (SII) was calculated as [(signal intensity on the in-phase image − signal intensity on the out-of-phase image) / (signal intensity on the in-phase image)] × 100%. We determined the averages of the minimum, mean, and maximum signal intensity values measured on three consecutive images. When that was not possible (for smaller lesions), we used one or two images. We employed a region of interest that covered one half to two thirds of the mass. All indices were compared with metabolite ratios derived from spectroscopy: lactate/creatine; glutamine-glutamate/creatine; choline/creatine; choline/lipid; 4.0–4.3 ppm/Cr; and lipid/creatine. RESULTS: Of the 97 patients evaluated, 69 were diagnosed with adenomas and 28 were diagnosed with nonadenomas. All SII measurements and spectroscopy-derived metabolite ratios were significant to the differentiation between adenomas and nonadenomas, except for the lipid/creatine and choline/lipid ratios. In 37.8% of the cases, it was not possible to perform spectroscopy. When it was possible, the lactate/creatine ratio was found to have higher accuracy than did the SII. CONCLUSION: Determining the SII and metabolite ratios increased the accuracy of the differential diagnosis of adrenal adenomas.

Keywords: Adrenal glands; Adrenal gland neoplasms; Adenoma/diagnostic imaging; Magnetic resonance imaging/methods; Proton magnetic resonance spectroscopy/methods.