High b-value diffusion-weighted magnetic resonance imaging for gallbladder lesions: differentiation between benignity and malignancy
ABSTRACT BACKGROUND: Recently, the clinical application of diffusion-weighted magnetic resonance imaging (DWI) has been expanding to abdominal organs. However, only a few studies on gallbladder diseases have been published. The aim of this study was to evaluate the usefulness and limitations of high b-value DWI for gallbladder diseases. METHODS: A total of 153 patients (mean age 60 ± 15 years, 78 males) who had undergone DWI for evaluating gallbladder wall thickening or polypoid lesions were included in this study. Of these 153 patients, 36 had gallbladder cancer and 117 had benign gallbladder diseases (67 chronic cholecystitis, 44 adenomyomatosis, four cholesterol polyp, one gallbladder adenoma, and one xanthogranulomatous cholecystitis). We evaluated the positive signal rate with DWI and the apparent diffusion coefficient (ADC) value of each disease. RESULTS: The positive signal rate with DWI was significantly higher in gallbladder cancer (78 %) than in benign gallbladder diseases (22 %) (p < 0.001). The mean ADC value of gallbladder cancer was (1.83 ± 0.69) × 10(-3) mm(2)/s and that of benign gallbladder diseases was (2.60 ± 0.54) × 10(-3) mm(2)/s (p < 0.001). Benign gallbladder diseases with acute cholecystitis or a history of that had a higher positive signal rate with DWI (p < 0.001) and a lower ADC value (p = 0.018) than those without such conditions. CONCLUSION: DWI can contribute to the improvement of the diagnostic capability for gallbladder wall thickening or polypoid lesions by compensating for weaknesses of other modalities by its many advantages, although cases with acute cholecystitis or such history sometimes show false-positive on DWI.
SourceAvailable from: Reiji Sugita[Show abstract] [Hide abstract]
ABSTRACT: Background The aim of this study was to evaluate the usefulness of high b-value diffusion-weighted magnetic resonance imaging (DWI) for evaluating the histological degree of malignancy in patients with intraductal papillary mucinous neoplasm (IPMN).MethodsA total of 35 patients (mean age 68 ± 10 years, 23 males) who had undergone DWI before surgery were included in this study. Of these 35 patients, 13 had IPMN with low- or intermediate-grade dysplasia, eight had IPMN with high-grade dysplasia, and 14 had IPMN with an associated invasive carcinoma. We evaluated the positive signal rate on DWI and the apparent diffusion coefficient (ADC) value of each pathology.ResultsThe positive signal rate on DWI of IPMN with low- or intermediate-grade dysplasia, of IPMN with high-grade dysplasia, and of IPMN with an associated invasive carcinoma were 0% (0/13), 38% (3/8), and 93% (13/14), respectively. The sensitivity, specificity, and accuracy for malignancy (IPMN with high-grade dysplasia or IPMN with an associated invasive carcinoma) using DWI were 73%, 100%, and 83%, respectively. The mean ADC value of malignancy was significantly lower than that of benignity (P = 0.002).Conclusions Diffusion-weighted magnetic resonance imaging, easily applicable in addition to conventional MRI, is considered an efficient modality for evaluating the histological degree of malignancy in patients with IPMN.Journal of Hepato-Biliary-Pancreatic Sciences 11/2014; 21(11). DOI:10.1002/jhbp.135 · 2.31 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Potentially, diffusion-weighted magnetic resonance imaging (DWI) can assess the functional information on concerning the status of tissue cellularity, because increased cellularity is associated with impeded diffusion. DWI in the hepatobiliary and pancreatic regions has demonstrated the usefulness to detect malignant lesions and differentiate them from benign lesions. However, it has been shown more recently that there is some overlap in ADC values for benign and malignant neoplasms. Moreover, some non-neoplastic lesions in the hepatobiliary and pancreatic regions exhibit restricted diffusion on DWI, because of pus, inflammation, or high cellularity. Focal eosinophilic liver disease, hepatic inflammatory myofibroblastic tumor, granulomatous liver disease, acute cholecystitis, xanthogranulomatous cholecystitis, focal pancreatitis, or autoimmune pancreatitis frequently exhibit restricted diffusion on DWI, which may be confused with malignancy in the hepatobiliary and pancreatic regions. Thus, DWI should not be interpreted in isolation, but in conjunction with other conventional images, to avoid the diagnostic pitfalls of DWI. Nevertheless, the presence of diffusion restriction in the non-neoplastic lesions sometimes provides additional information regarding the diagnosis, in problematic patients where conventional images have yielded equivocal findings. DWI may help differentiate hepatic abscess from malignant necrotic tumors, gallbladder empyema from dense bile or sludge in the gallbladder, and pylephlebitis from bland thrombosis in the portal vein. Therefore, knowledge of DWI findings to conventional imaging findings of diffusion-restricted non-neoplastic conditions in the hepatobiliary and pancreatic regions helps establishing a correct diagnosis.Abdominal Imaging 09/2014; 40(3). DOI:10.1007/s00261-014-0235-5 · 1.73 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: The aim of the current study was to assess the efficiency of the apparent diffusion coefficient (ADC) measurement in diagnosis of acute cholecystitis and in differentiation of cholecystitis from extrinsic benign gallbladder wall thickening. Forty patients who were diagnosed to have acute cholecystitis by ultrasonographic examination were included in this study. The control group consisted of 18 patients without symptoms of gallstones and cholecystitis whose gallbladder walls were thickened due to cirrhotic ascites. Both groups were examined using diffusion weighted imaging, and the mean ADC values were compared using Student's t-test. The diagnoses of the 40 patients were proven by histopathological examination. The mean ADC values of patients diagnosed with cholecystitis (1.68 +/- A 0.36 x 10(-3) mm(2)/s) were significantly lower than the mean ADC values of the control group (2.35 +/- A 0.24 x 10(-3) mm(2)/s) (p < 0.05). Receiver operating characteristics curve analysis based on ADC revealed a cut-off value of 2.04 x 10(-3) mm(2)/s for the diagnosis of cholecystitis, with a sensitivity of 94 % and a specificity of 89.7 %. ADC value quantification may be an efficient method for making a diagnosis of cholecystitis and in differential diagnosis of cholecystitis from the extrinsic benign gallbladder wall thickening that can be seen during the course of cirrhotic ascites.Japanese journal of radiology 06/2014; 32(9). DOI:10.1007/s11604-014-0343-8 · 0.74 Impact Factor