Accuracy of magnetic resonance imaging in differentiating between benign and malignant vertebral lesions: role of diffusion-weighted imaging, in-phase/opposed-phase imaging and apparent diffusion coefficient.
OBJECTIVE
To determine the ability of MRI to distinguish between benign and malignant vertebral lesions.


METHODS
We included 85 patients and studied a total of 213 vertebrae (both pathologic and normal). For each vertebra, we determined whether the lesion was hypointense in T1-weighted sequences and whether it was hyperintense in STIR and in diffusion-weighted sequences. We calculated the in-phase/out-of-phase quotient and the apparent diffusion coefficient for each vertebra. We combined parameters from T1-weighted, diffusion-weighted, and STIR sequences to devise a formula to distinguish benign from malignant lesions.


RESULTS
The group comprised 60 (70.6%) women and 25 (29.4%) men with a mean age of 67±13.5 years (range, 33-90 y). Of the 85 patients, 26 (30.6%) had a known primary tumor. When the lesion was hypointense on T1-weighted sequences, hyperintense on STIR and diffusion-weighted sequences, and had a signal intensity quotient greater than 0.8, the sensitivity was 97.2%, the specificity was 90%, and the diagnostic accuracy was 91.2%. If the patient had a known primary tumor, these values increased to 97.2%, 99.4%, and 99%, respectively.


CONCLUSIONS
Benign lesions can be distinguished from malignant lesions if we combine the information from T1-weighted, STIR, and diffusion-weighted sequences together with the in-phase/out-of-phase quotient of the lesion detected in the vertebral body on MRI.
Departamento de Diagnóstico por Imagen, Hospital Universitario Fundación Alcorcón, Alcorcón, España. Electronic address: jmartel@fhalcorcon.es.
J
J
Martel Villagrán
Departamento de Diagnóstico por Imagen, Hospital Universitario Fundación Alcorcón, Alcorcón, España.
Á
Á
Bueno Horcajadas
Departamento de Diagnóstico por Imagen, Hospital Universitario Fundación Alcorcón, Alcorcón, España.
E
E
Pérez Fernández
Departamento de Diagnóstico por Imagen, Hospital Son Llàtzer, Palma de Mallorca, España.
S
S
Martín Martín
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D013122:Spinal Diseases / Q000000981:diagnostic imaging*; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging*
Apparent diffusion coefficient; Coeficiente de difusión aparente; Diffusion; Difusión; Fase/fuera de fase; Fracturas; Fractures; In phase/out of phase; Magnetic resonance imaging; Metastasis; Metástasis; Osteoporosis; Resonancia magnética; Vertebra; Vértebra