Breast tumor imaging with ultra low field MRI.
Ultra low field MRI was evaluated for breast tumor imaging. Twenty-seven patients with a known or suspected breast malignancy were imaged preoperatively with a T2-weighted gradient-echo sequence. Additional IR- and gradient-echo sequences were used for measurements of T1 and T2 relaxation times. Seventeen resected specimens were also imaged within four hours after removal. Nineteen of 23 carcinomas detected at mammography were also detected with MRI (sensitivity 83%), and one of four benign cases was evaluated as pathologic (specificity 75%). Most of the tumors had T1 and T2 relaxation times longer than those of normal breast parenchyma. The T1 values of the tumors were significantly different from the T1 values of fat (p = .0002) and breast parenchyma (p = .0151). The tumor T2 values differed significantly from the T2 of breast parenchyma (p = .0223) but not from that of fat (p = .1475). In vitro tumor measurements were similar to the in vivo measurements. Despite these statistically significant findings, the calculated relaxation times were not considered sufficiently reliable for the clinical evaluation of breast tumors.
Dean
K I
KI
Department of Diagnostic Radiology, University of Turku, Finland.
Komu
M
M
D000328:Adult; D000368:Aged; D001706:Biopsy; D001940:Breast / Q000473:pathology; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008279:Magnetic Resonance Imaging; D008327:Mammography; D008875:Middle Aged; D012680:Sensitivity and Specificity