title: Adrenal masses: characterization with T1-weighted MR imaging.
abstract: The ability of a T1-weighted spin-echo magnetic resonance (MR) sequence to allow differentiation of benign from malignant adrenal masses at 0.5 T was investigated in 28 patients with 35 adrenal masses. All nine lesions with an adrenal mass-liver signal intensity ratio of 0.71 or less were metastases, and all 15 with a ratio of 0.78 or more were adenomas. Eleven masses (31%)--including six adenomas, three metastases, a pheochromocytoma, and a neuroblastoma--had ratios between these values. Nine of ten masses with adrenal mass-fat intensity ratios of 0.35 or less were metastases, and all 12 with ratios of 0.42 or more were benign. Eleven masses (31%), four malignant and one benign, had ratios between these values. The ratios for two masses could not be calculated due to lack of fat. The specificity of T1-weighted MR imaging in differentiating benign from malignant adrenal masses appears similar to that reported for T2-weighted imaging. However, significant overlap occurred, as has also been reported for T2-weighted imaging. While both imaging sequences may help distinguish benign from malignant adrenal masses in some cases, biopsy is still necessary when an accurate histologic diagnosis is essential.
authors.affiliation: Department of Radiology, Emory University School of Medicine, Atlanta, GA 30322.
authors.forename: J L
authors.initials: JL
authors.lastname: Chezmar
authors.forename: S M
authors.initials: SM
authors.lastname: Robbins
authors.forename: R C
authors.initials: RC
authors.lastname: Nelson
authors.forename: H V
authors.initials: HV
authors.lastname: Steinberg
authors.forename: W E
authors.initials: WE
authors.lastname: Torres
authors.forename: M E
authors.initials: ME
authors.lastname: Bernardino
mesh_terms: D000236:Adenoma / Q000175:diagnosis*; D000310:Adrenal Gland Neoplasms / Q000175:diagnosis* / Q000556:secondary; D000311:Adrenal Glands / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*