title: Quantitative Sodium MR Imaging at 7 T: Initial Results and Comparison with Diffusion-weighted Imaging in Patients with Breast Tumors.
abstract: Purpose To investigate the clinical feasibility of a quantitative sodium 23 ((23)Na) magnetic resonance (MR) imaging protocol developed for breast tumor assessment and to compare it with 7-T diffusion-weighted imaging (DWI). Materials and Methods Written informed consent in this institutional review board-approved study was obtained from eight healthy volunteers and 17 patients with 20 breast tumors (five benign, 15 malignant). To achieve the best image quality and reproducibility, the (23)Na sequence was optimized and tested on phantoms and healthy volunteers. For in vivo quantification of absolute tissue sodium concentration (TSC), an external phantom was used. Static magnetic field, or B0, and combined transmit and receive radiofrequency field, or B1, maps were acquired, and image quality, measurement reproducibility, and accuracy testing were performed. Bilateral (23)Na and DWI sequences were performed before contrast material-enhanced MR imaging in patients with breast tumors. TSC and apparent diffusion coefficient (ADC) were calculated and correlated for healthy glandular tissue and benign and malignant lesions. Results The (23)Na MR imaging protocol is feasible, with 1.5-mm in-plane resolution and 16-minute imaging time. Good image quality was achieved, with high reproducibility (mean TSC values ± standard deviation for the test, 36 mmol per kilogram of wet weight ± 2 [range, 34-37 mmol/kg]; for the retest, 37 mmol/kg ± 1 [range, 35-39 mmol/kg]; P = .610) and accuracy (r = 0.998, P < .001). TSC values in normal glandular and adipose breast tissue were 35 mmol/kg ± 3 and 18 mmol/kg ± 3, respectively. In malignant lesions (mean size, 31 mm ± 24; range, 6-92 mm), the TSC of 69 mmol/kg ± 10 was, on average, 49% higher than that in benign lesions (mean size, 14 mm ± 12; range, 6-35 mm), with a TSC of 47 mmol/kg ± 8 (P = .002). There were similar ADC differences between benign ([1.78 ± 0.23] × 10(-3) mm(2)/sec) and malignant ([1.03 ± 0.23] × 10(-3) mm(2)/sec) tumors (P = .002). ADC and TSC were inversely correlated (r = -0.881, P < .001). Conclusion Quantitative (23)Na MR imaging is clinically feasible, may provide good differentiation between malignant and benign breast lesions, and demonstrates an inverse correlation with ADC. (©) RSNA, 2016 Online supplemental material is available for this article.
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Olgica
authors.initials: O
authors.lastname: Zaric
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Katja
authors.initials: K
authors.lastname: Pinker
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Stefan
authors.initials: S
authors.lastname: Zbyn
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Bernhard
authors.initials: B
authors.lastname: Strasser
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Simon
authors.initials: S
authors.lastname: Robinson
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Lenka
authors.initials: L
authors.lastname: Minarikova
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Stephan
authors.initials: S
authors.lastname: Gruber
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Alex
authors.initials: A
authors.lastname: Farr
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Christian
authors.initials: C
authors.lastname: Singer
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Helbich
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Siegfried
authors.initials: S
authors.lastname: Trattnig
authors.affiliation: From the MR Center of Excellence (MRCE), Department of Biomedical Imaging and Image-guided Therapy (O.Z., S.Z., B.S., S.R., L.M., S.G., S.T., W.B.), Division of Molecular and Gender Imaging, Department of Biomedical Imaging and Image-guided Therapy (K.P., T.H.H.), and Department of Obstetrics and Gynecology (A.F., C.S.), Medical University of Vienna, Lazarettgasse 14, A-1090, Vienna, Austria; and Christian Doppler Laboratory for Clinical Molecular MRI, Christian Doppler Forschungsgesellschaft, Vienna, Austria (S.T.).
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Bogner
mesh_terms: D000328:Adult; D000368:Aged; D001940:Breast / Q000000981:diagnostic imaging; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012979:Sodium Radioisotopes
chemical_list: D012979:Sodium Radioisotopes