Abstract:
Magnetic Resonance Spectroscopy (MRS) and Diffusion Techniques (DWI) are
currently being used more extensively than conventional Magnetic Resonance
Imaging (MRI) in diagnosing lesions, therefore the main objective of this study
was to evaluate the accuracy of MRS and DWI in characterization of female
breast cancer. The data was collected from 100 patients with breast lesions in
Saudi German Hospital using MRS and DWI. MRI was performed using a 1.5-T
system (Magnetom symphony 1.5 Tesla, Siemens-Germany). For Magnetic
Resonance Spectroscopy a Single-voxel MRS (SVS) was applied using a Point-
resolved Spectroscopy Sequence (PRESS). All patients underwent diffusion
weighted images with b values, 500, 1,000, 1,500, 2,000, and 3,000 s/mm 2.
Apparent Diffusion Coefficient (ADC) values were generated automatically
through soft-ware system. If a high-signal-intensity lesion was detected in high-
b-value (b = 3,000 s/mm2) images, that lesion was defined as malignant. We
observed that the signal-intensity of benign lesion disappeared in the high-b-
value (b = 3,000 s/mm2) and continue in brightness in case of malignant. The
ADC values of the mass was calculated from two different gradient factors (b 1 =
500 s/mm2 and b2 = 1,500 s/mm2) for positive results. For the in vivo MRS
studies, each spectrum was evaluated for the presence of choline based on
consensus reading, the results of this study showed that the sensitivity, specificity
and accuracy of MRS were 100%, 90% and 93% respectively. For DWI, lesions
with ADC values (> 1.5 mm2/s) were considered benign where as lesions with
ADC values (< 1 mm2/s) were considered malignant, those lesions with ADC
values (>1–<1.5 mm2/s) represented the overlap cases (between benign and
malignant). This method of using ADC values for the detection of malignant
lesions showed a sensitivity, specificity and accuracy of 96%, 86% and 89%
respectively. In conclusion MR spectroscopy was useful for characterizing breast
lesions measuring 1.5 cm or larger and diffusion-weighted imaging was useful
for characterizing small and large lesions despite of overlap in some cases.
