Premium
Diagnostic utility of diffusion‐weighted MR imaging and apparent diffusion coefficient value for the diagnosis of adrenal tumors
Author(s) -
Tsushima Yoshito,
TakahashiTaketomi Ayako,
Endo Keigo
Publication year - 2009
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.21616
Subject(s) - effective diffusion coefficient , medicine , nuclear medicine , diffusion mri , echo planar imaging , magnetic resonance imaging , radiology
Purpose To determine the utility of diffusion‐weighted MR imaging (DWI) for the diagnosis of adrenal tumors. Materials and Methods Forty‐two patients (24 men and 18 women; age, 61.5 ± 12.7 years old; range, 34–86 years) with 43 adrenal tumors (11 functioning cortical adenomas, 20 nonfunctioning cortical adenomas, 7 metastatic tumors, and 5 pheochromocytomas) were retrospectively investigated. DWIs were obtained by single‐shot spin‐echo type echo‐planar imaging sequence (1.5 Tesla [T]; TR = 8000 ms, TE = 72, b ‐factor = 0 and 1000 s/mm 2 ), and apparent diffusion coefficient (ADC) value was calculated. Chemical shift images were obtained by gradient echo sequence (TR = 161, TE = 2.38 [out‐of‐phase, OP] and 4.76 [in‐phase, IP], FA = 60), and the signal intensity index (SII; [IP‐OP]/IP *100%) was calculated. Results There was no difference in ADC values between adenomas (1.09 ± 0.29*10 −3 mm 2 /s; range, 0.52–1.64) and metastatic tumors (0.85 ± 0.26*10 −3 ; 0.51–1.23; p = 0.14). Pheochromocytomas showed the higher mean ADC value (1.59 ± 0.34*10 −3 ; 1.04–1.96) compared with those of adenomas or metastatic tumors ( P < 0.05 and P < 0.005, respectively). The mean SII of adenomas (62.1 ± 17.9%; 14.5–88.4) was significantly higher than those of pheochromocytomas (4.0 ± 10.0%; −19.6–3.3; P < 0.005) or metastatic tumors (−1.5 ± 11.7%; −18.3–8.2; P < 0.01). There was no correlation between ADC values and SII. Conclusion Although pheochromocytomas showed higher ADC values, we did not find that ADC value had diagnostic utility for differentiating adenomas and metastatic tumors. J. Magn. Reson. Imaging 2009;29:112–117. © 2008 Wiley‐Liss, Inc.