Aperfeiçoamento de uma técnica de espectroscopia por ressonância magnética para diferenciação de nódulos e massas adrenais

• Ano de defesa: 2010
• Autor(a) principal: Melo, Homero José de Farias e [UNIFESP]
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Câncer suprarrenal; Ressonância magnética; Espectroscopia
• Link de acesso: http://repositorio.unifesp.br/handle/11600/8953

Purpose: To improve 1H MRS protocol for adrenal glands’ nodules and masses differentiation, especially adenomas, pheochromocytomas, carcinomas and metastasis. Methods: We have evaluated prospectively, 118 patients (36 men and 82 women), mean age 57.3 ± 13.3 years-old, with 138 adrenal nodules or masses. The exams were performed with 1.5-T MR imaging and 43 mT/m gradients system (Magnetom Sonata; Siemens Medical Systems, Erlangen, Germany) and 1.5-T MR imaging and 33 mT/m gradients system (Magnetom Espree; Siemens Medical Systems, Erlangen, Germany). The multivoxel grid cranium-caudal adjustment was performed using three sagittal sequences (maximum inspiration, expiration and free breathing) and left-right and anterior-posterior by using axial and coronal sequences. We used a multivoxel system acquired by hybrid PRESS CSI 2D sequence commercially available by Siemens Medical Systems (Erlangen, Germany). We defined also a post-processing and analysis systematic for all off the masses. The post-processing was performed at a workstation (LEONARDO®; Siemens Medical Systems) with spectroscopy analysis dedicated program. The spectroscopic analysis was interpreted by means of visual inspection and metabolite peak amplitude measurements, lipid (Lip), choline (Cho), creatine (Cr) and catecholamines (4.0-4.3 ppm) addition of lactate (Lac), glutamine plus glutamate (Glx). We separated too different lipid picks presents in each group studied. We have applied the previously implanted mathematics ratio (Cho/Cr; 4.0-4.3/Cr; Lip/Cr e Cho/Lip) and we tested another’s (Lac/Cr e Glx/Cr). We studied the lesion size and Glx/Cr correlation. Results: Using the sequences indicated in 1H MRS and the post-processing and analysis systematic was possible to do the exams in 123 (89.13%) included masses with earlier published results reproduction. The metabolic ratio Lac/Cr ≤-7.449 had 90.9% sensibility and 77.8% specificity in pheochromocytomas and carcinomas differentiation. There was no difference between groups for Glx/Cr ratio (p>0,05), but we had inferred adenoma, carcinoma, pheochromocytomas lesion’s size and this metabolic ratio value correlation. We have founded androstenodiona, DHEA-S, aldosterona and cortisol in all off the studied masses and the adenoma was differed from other by having increased cortisol levels. Conclusions: From the outlined 1H MRS sequence it was possible to establish an effective procedure for adrenal glands nodules and masses differentiation. This MR and MRS acquisition protocol allowed the exam realization in 123 (89.13%) masses with more than 1.0 cm lesion. The post-processing systematic was effective in nodules differentiation.