Relationship of temporal resolution to diagnostic performance for dynamic contrast enhanced MRI of the breast.
OBJECTIVE
To investigate the relationship between temporal resolution of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) and classification of breast lesions as benign versus malignant.


METHODS
Patients underwent T(1)-weighted DCE MRI with 15 s/acquisition temporal resolution using 1.5 Tesla (n = 48) and 3.0T (n = 33) MRI scanners. Seventy-nine patients had pathologically proven diagnosis and 2 had 2 years follow-up showing no change in lesion size. The temporal resolution of DCE MRI was systematically reduced as a postprocessing step from 15 to 30, 45, and 60 s/acquisition by eliminating intermediate time points. Average wash-in and wash-out slopes, wash-out percentage changes, and kinetic curve shape (persistently enhancing, plateau, or wash-out) were compared for each temporal resolution. Logistic regression and receiver operating characteristic (ROC) curve analysis were used to compare kinetic parameters and diagnostic accuracy.


RESULTS
Sixty patients (74%) had malignant lesions and 21 patients (26%) had benign lesions. All temporal-resolution parameters significantly predicted benign versus malignant diagnosis (P < 0.05). However, 45 s/acquisition and higher temporal-resolution datasets showed higher accuracy than the 60 s/acquisition dataset by ROC curve analysis (0.72 versus 0.69 for average wash-in slope; 0.85 versus 0.82, for average wash-out slope; and 0.88 versus 0.80 for kinetic curve shape assessment, for 45 s/acquisition versus 60 s/acquisition temporal-resolution datasets, respectively (P = 0.027).


CONCLUSIONS
DCE MRI data with at least 45-s temporal resolution maximized the agreement between the kinetic parameters and correct classification of benign versus malignant diagnosis.
El Khouli
Riham H
RH
National Institutes of Health, Department of Radiology and Imaging Sciences, Bethesda, Maryland, USA.
Macura
Katarzyna J
KJ
Barker
Peter B
PB
Habba
Mohamed R
MR
Jacobs
Michael A
MA
Bluemke
David A
DA
D000328:Adult; D000368:Aged; D019540:Area Under Curve; D001940:Breast / Q000473:pathology*; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007700:Kinetics; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors
D003287:Contrast Media