T1 Measurements by TOMROP: First Experiences and Applications in In Vivo Breast Studies

Abstract

Since 1984 more than 600 patients with suspected breast disease have undergone MRI at our department, including more than 400 examinations using Gd-DTPA. Besides MRI with Gd-DTPA, in the early days of MRI T1 and T2 measurements were considered to have potential as a means of tissue characterization. However, despite all efforts the diagnostic value of T1 and T2 measurements obtained from clinical in vivo imaging has been disappointing. Several reasons have been discussed, including inaccuracy of T1 and T2 determination when based on two measurements only, systematic errors caused by the slice or volume selection method of the imaging system, and possible overlap of tissue parameters of histologically different tissues due to biologically similar composition. Due to these restrictions it is not yet clear whether the calculation of T1, T2, and proton density is a possible means of tissue characterization. To obtain reliable results, it is necessary to use very precise methods for T1 and T2 quantification. This is a report about our experiences concerning the in vivo determination of T1 from multiple measurement points using a sequence scheme called TOMROP.