LETTER TO THE EDITOR
Diffusion-Weighted Imaging in the Characterization of Breast Lesions Ali Kemal Sivrioglu,1 Hakan Mutlu,2 Kemal Kara,2 and G€ uner S€onmez2 To the Editor: We read the interesting article of Kul et al, "Diagnostic efficacy of the diffusion-weighted imaging in the characterization of different types of breast lesions," which was published in the November 2014 issue of the journal.1 The study included fairly important information which was very useful to us. However, we would like to make a few contributions. The Discussion section of the study compares apparent diffusion coefficient (ADC) values obtained for benign and malignant lesions with similar articles published in the literature. In that section, it is specified that ADC values of lesions and corresponding thresholds are the lowest values established in the literature and the possible reasons for the low values. In our opinion, one of the reasons for those low values of ADC obtained in that study is that gradients used for diffusion-weighted imaging were obtained with values of b 5 50, 400, and 1000 sec/mm2, not the use of b 5 0 sec/mm2. If ADC maps were generated based on b 5 0 sec/mm2 values in the study, the resulting ADC values would be higher.
SUVmax (maximum standard uptake values) are used for tumor assessment in positron emission tomography / computed tomography (PET/CT) imaging, a physiological imaging technique. This value indicates and quantifies the tumor cell region that has the most FDG (fluorodeoxyglucose) uptake. In another physiological imaging DWI, the area with the most limited diffusion clearly shows the tumor. The most appropriate parameter to show and quantify the related areas is the minimum ADC (ADCmin).2 We believe that minimum ADC values may give more accurate results compared to mean ADC values. 1
Department of Radiology, Kasmpasa Military Hospital, Istanbul, Turkey 2 Department of Radiology, GATA Haydarpasa Training Hospital, Istanbul, Turkey
References 1.
Kul S, Eyuboglu I, Cansu A, Alhan E. Diagnostic efficacy of the diffusionweighted imaging in the characterization of different types of breast lesions. J Magn Reson Imaging 2014;40:1158–1164.
2.
Sivrioglu AK, Incedayi M, Urhan M. Diffusion-weighted MRI as predictor of tumor treatment response. AJR Am J Roentgenol 2012;199:W415.
DOI: 10.1002/jmri.24848
C 2015 Wiley Periodicals, Inc. V 851
Diffusion-Weighted Imaging in the Characterization of Breast Lesions Ali Kemal Sivrioglu,1 Hakan Mutlu,2 Kemal Kara,2 and G€ uner S€onmez2 To the Editor: We read the interesting article of Kul et al, "Diagnostic efficacy of the diffusion-weighted imaging in the characterization of different types of breast lesions," which was published in the November 2014 issue of the journal.1 The study included fairly important information which was very useful to us. However, we would like to make a few contributions. The Discussion section of the study compares apparent diffusion coefficient (ADC) values obtained for benign and malignant lesions with similar articles published in the literature. In that section, it is specified that ADC values of lesions and corresponding thresholds are the lowest values established in the literature and the possible reasons for the low values. In our opinion, one of the reasons for those low values of ADC obtained in that study is that gradients used for diffusion-weighted imaging were obtained with values of b 5 50, 400, and 1000 sec/mm2, not the use of b 5 0 sec/mm2. If ADC maps were generated based on b 5 0 sec/mm2 values in the study, the resulting ADC values would be higher.
SUVmax (maximum standard uptake values) are used for tumor assessment in positron emission tomography / computed tomography (PET/CT) imaging, a physiological imaging technique. This value indicates and quantifies the tumor cell region that has the most FDG (fluorodeoxyglucose) uptake. In another physiological imaging DWI, the area with the most limited diffusion clearly shows the tumor. The most appropriate parameter to show and quantify the related areas is the minimum ADC (ADCmin).2 We believe that minimum ADC values may give more accurate results compared to mean ADC values. 1
Department of Radiology, Kasmpasa Military Hospital, Istanbul, Turkey 2 Department of Radiology, GATA Haydarpasa Training Hospital, Istanbul, Turkey
References 1.
Kul S, Eyuboglu I, Cansu A, Alhan E. Diagnostic efficacy of the diffusionweighted imaging in the characterization of different types of breast lesions. J Magn Reson Imaging 2014;40:1158–1164.
2.
Sivrioglu AK, Incedayi M, Urhan M. Diffusion-weighted MRI as predictor of tumor treatment response. AJR Am J Roentgenol 2012;199:W415.
DOI: 10.1002/jmri.24848
C 2015 Wiley Periodicals, Inc. V 851
