The Study With MR Diffusion-weighted Imaging(DWI) Of Female Complex Adnexal Masses

Objective To compare signal characteristics and image qualities of MRdiffusion-weighted imaging (DWI) at3.0T and1.5T in patients with the complexadnexal masses.Materials and methods: Magnetic resonance imaging including routine MRI and DWI（b=0s/mm2、400s/mm2、600s/mm2、800s/mm2、1000s/mm2） of1.5T (50patientswith31benign and19malignant lesions) and3.0T (53patients with29benign and24malignant lesions) was performed in103patients histopathologically provedadnexal masses．The optimal b value was analyzed, and the apparent diffusion coefficient(ADC) value and signal intensity (SI) value and contrast to noise ratio (CNR)of solid and cystic components in adnexal masses from both3.0T and1.5T MRI wererespectively compared statistically．Results The800s/mm2is the optimal b value in demonstrating adnexal masses at1.5T and3.0T. The SI value of solid and cystic components in adnexal masses s at1.5T and3.0Tdecreased with increasing b values. The decreasing of SI value is significant higher ofcystic lesions than of solid lesions, and no significant different between at3.0T andat1.5T. The ADC value of solid lesions at1.5T and3.0T decreased with increasing bvalues, so did that of cystic lesions at1.5, but that of cystic lesions at3.0T did not. TheADC value of cystic lesions is higher than that of solid lesions. The CNR of solid andcystic components in adnexal masses were significantly higher at3.0T than at1.5T onall b values（all P=0.000）. There was no significant difference of SI value of solidlesions between1.5T and3.0T when b=800s/mm2（P>0.05）, and significant differenton b400、b600、b1000（all P<0.05）; so did that of ofADC value of cystic lesions.Thedifference in SI value of cystic lesions between1.5T and3.0T when b400had nostatistically significant （P>0.05）, statistically significant on b600、b800、b1000（allP<0.05）. The difference in ADC value of solid lesions between1.5T and3.0T on all bvalues had no statistically significant （all P>0.05）.Conclusions MR diffusion-weighted imaging at3.0T comparing with1.5T hasquantitative and qualitative advantages of evaluating for adnexal masses. Objective To evaluate the role of MR diffusion-weighted imaging (DWI) in thediagnosis for cystic components of the complex adnexal masses in female patients.Materials and methods Totally82women with cystic components of the complexadnexal masses confirmed by pathology were collected retrospectively．82cases (mean age48.5years; age range16–84years) were histopathologically diagnosed as serous lesions24(serous cystadenoma8, borderline and invasive serous cystadenoma16),mucinous lesions23(mucinous cystadenoma14, borderline and invasive mucinouscystadenoma9), purulent lesions (tubo ovarian abscess)14, hemorrhagic lesions(endometrial cyst)5, physiologic cyst6, fatty lesions (cystic teratoma)10.All patientsunderwent routine MRI and DW（Ib=800s/mm2）．The apparent diffusion coefficient (ADC)average value and signal intensity (SI) average value of cystic lesions of thecomplex adnexal masses were respectively compared statistically．Results The ADC average value(10-4mm2/s) and SI average value of different cysticlesions on b=800s/mm2were as follows：serous cystadenoma (25.1±4.2，82.4±40.0),mucinous cystadenoma (23.3±7.8,107.5±78.3), cystic teratoma (4.5±3.2,56.2±27.4), physiologic cyst was (31.8±4.7,83.8±16.2), abscess (19.3±5.7,123.4±44.9),endometrial cyst (9.4±6.3,116.9±36.1).The mean ADC value of the cysticcomponents differed among different cystic lesions （P=0.000）. There were significantdifference of the ADC mean value between fat (cystic teratoma) and blood(endometrial cyst) and physiologic cyst (all P<0.05), and significant difference betweenthem and abscess or serous fluid or mucinous fluid (all P<0.05), and no significantdifference between abscess and serous fluid and mucinous fluid(P>0.05). The differencein SI mean value of cystic component among6groups had no statistically significant（P>0.05）. TheADC(10-4mm2/s) and SI mean value of the serous fluid did not differbetween benign (24.3±6.0,95.6±57.3, respectively) and malignant (25.7±2.3，72.5±16.7, respectively) adnexal masses（P>0.05）. There were no significant difference ofthe ADC(10-4mm2/s) value of the mucinous fluid between benign(22.4±9.2) andmalignant (24.6±5.8) adnexal masses（P>0.05）, and significant difference of SImean value between benign (137.8±91.3) and malignant (69.0±30.9) masses（P<0.05）.Conclusions By analysis of the ADC and SI values for cystic lesions of thecomplex adnexal masses in female patients, we found that the ADC and SI values couldprovide qualitative value，and that DWI combined with routine MRI was helpful fordifferential diagnosis of cystic lesions of complex adnexal masses. Objective To prospectively assess the contribution of diffusion-weighted MRimaging (DWI) for characterizing complex adnexal masses.Materials and methods103women with complex adnexal masses confirmed bypathology and underwent MR imaging including DWI before surgery. Conventionalmorphological MR imaging criteria were prospectively recorded in addition to signalintensity(SI) value and apparent diffusion coefficient (ADC) value on DWI (b=800s/mm2）measurements of cysticand solid components. Positive likelihood ratios(PLR)were calculated for predicting benignity and malignancy.Results Of103cases (mean age50years; age range16–84years),60cases werehistopathologically diagnosed as benign lesions and43cases of malignant tumors.ADC measurements did not contribute to differentiating benign from malignantadnexal masses. There were significant difference of SI mean value of solid or cysticcomponents between benign and malignant adnexal masses on b800DWI (all P<0.05).The sensitivity, specificity,accuracy and PLR were41.7%,90.7%,73.1%,4.5,respectively by using a threshold SI mean value of of solid components greater than80for predicting malignancy. The sensitivity, specificity, accuracy and PLR were56.3%,87.2%,78.5%,4.4, respectively by using a threshold SI value of cystic components ofgreater than75for predicting benignity. The most significant criteria for predictingbenignity were low signal intensity within the solid component (PLR=4.5) on b800DWI,low T2WI signal intensity within the solid component (PLR=4.0), absence of solid portion(PLR=4.3), absence of peritoneal implants (PLR=1.4) and absence of papillaryprojections (PLR=1.7). The most significant criteria for predicting malignancy wereperitoneal implants, papillary projections (PLR=4.2), high signal intensity within thesolid component (PLR=2.0) on b800DWI, solid portion (PLR=2.2), solid component withintermediate T2signal(PLR=1.7). All masses that displayed simultaneously low signalintensity within the solid component on T2-weighted and on b800DWI were benign.Alternatively, the presence of a solid component with intermediate T2signal and highb800signal intensity was associated with a PLR of3.9for a malignant adnexal tumor.Conclusions DWI signal intensity combined with routine MRI is an accurate tool forpredicting benignity or malignancy of complex adnexal masses.