MRI characteristics of solid papillary carcinomas in situ of breast / 中国介入影像与治疗学

Objective To evaluate MRI characteristics of solid papillary carcinomas (SPCs) in situ of the breast.Methods A retrospective study included 5 patients with pathologically confirmed SPC in situ was performed.MRI data before operation including conventional MRI,dynamic contrast enhanced MRI (DCE-MRI) and DWI were analyzed.Results All the lesions showed iso/hypointensity on T1 FSPGR sequence,iso/hyperintensity on FSE T2WI sequence and STIR sequence.Mass enhancements were observed for all lesions with oval or irregular shapes on DCE-MRI.The margin of lesions were circumscribed,and internal enhancements were homogeneous or heterogeneous.Time intensity curve appeared a rapid increase in initial contrast phases and platform or outflow types in delayed phases.All the lesions on DWI showed slightly hyperintensity with the ADC value range from 1.34 × 10-3 mm2/s to 1.96)× 10-3 mm2/s.Conclusion MRI manifestations of SPC are characteristics,which may provide valuable information to distinguish SPC in situ from other invasive breast carcinomas.

Values of kinetic features measured by computer-aided diagnosis for breast MRI / 中华放射学杂志

Objective To investigate the value of kinetic features measured by computer-aided diagnosis (CAD)for breast MRI.Methods One hundred and sixty four lesions diagnosed pathologically by operation or biopsy comprised the analysis set.Automated lesion kinetic information from CADStream programs for breast MRI was identified.Three CAD variables were compared for benign and malignant lesions: initial phase peak enhancement (greatest percentage of signal intensity increase on first contrast enhanced sequence),delayed phase enhancement categorized by a single type of kinetics comprising the largest percentage of enhancement (washout,plateau,or persistent),and delayed phase enhancement categorized by single most suspicious type of kinetics (any washout ＞ any plateau ＞ any persistent).Morphological characteristics of breast lesions were described according to breast imaging and reporting data system (BI-RADS).Initial phase peak enhancement mean values between benign and malignant breast lesions were compared by using Wilcoxon rank-sum test,delayed phase enhancement categorized by a single type of kinetics comprising the largest percentage of enhancement or by single most suspicious type of kinetics between benign and malignant breast lesions were compared by using Chi-square test.Results There were 72 benign and 92 malignant breast lesions.A total of 123 (75.0％) mass lesions were identified,and the other 41 (25.0％) lesions showed no mass.Thirty lesions were BI-RADS-MRI 2,68 lesions were BI-RADS-MRI 3,43 lesions were BI-RADS-MRI 4,23 lesions were BI-RADS-MRI 5.Initial phase peak enhancement mean values of benign and malignant lesions were 237％ (69％ to 629％)and 336％ (86％ to 793％),respectively.There was no significant difference between benign and malignant lesions in initial peak enhancement mean value (Z =-1.626,P =0.104).Delayed phase enhancement categorized by single most suspicious type of kinetics (any washout ＞ any plateau ＞ any persistent) for benign and malignant lesions were 15,10,47 and 2,3,87 respectively.There was a significant difference between benign and malignant lesions (x2 =23.562,P =0.000).Initial peak enhancement value ＜ 100％ or ≥100％ were 5 and 67 for benign lesions,3 and 89 for malignant lesions,respectively.There was no significant difference between benign and malignant lesions at 100％ threshold (x2 =1.181,P =0.277).Delayed phase enhancement categorized by a single type of kinetics comprising the largest percentage of enhancement (washout,plateau,or persistent) for benign and malignant lesions were 48,6,18 and 47,15,30 respectively.There was no significant difference between benign and malignant lesions (x2 =4.496,P =0.106).Conclusions Of CAD kinetics analyzed,only delayed enhancement categorized by most suspicious type is helpful for the differentiation between benign and malignant lesions.However,there is significant overlap between initial peak enhancement at 100％ threshold or delayed kinetics categorized by largest percentage enhancement types of benign and malignant lesions,so lesion morphologic features should be considered.

The comparative study of MR diffusion-weighted imaging and MR perfusion-weighted imaging in diagnosing soft tissue tumors / 中华放射学杂志

Objective To evaluate MR diffusion-weighted imaging (DWI)and MR perfusion-weighted imaging(PWI) in differentiating benign from malignant soft tissue tumors by comparing the related parameters. Methods Fifty patients with soft tissue tumors verified by pathology( benign 24, malignant 26) underwent DWI and dynamic contrast-enhanced T2 * -weighted PWI. DWI and PWI data of benign and malignant soft tissue tumors were acquired at the workstation and their difference was analyzed with t-test. The diagnostic accordance rate was verified with x2-test. Subjective overall performance of two techniques were evaluated with receiver operating characteristic (ROC) analysis. Results ADC values of benign and malignant tumors were (2. 03±0. 36) × 10-3 mm2/s, ( 1.52±0. 39) × 10-3 mm2/s,respectively. The signal intensity decrease of them during the first-pass perfusion (SIdecrease ) were ( 13.54 ± 3.37 )%, (47. 57 ± 5. 21 ) % ,respectively. The maximum linearity slope rate of TIC ( SSmax ) of them were ( 5.51 ± 2. 54 ) %, (7.94 ± 3. 33) %, respectively. There were significant differences between benign and malignant tumors of ADC value and SIdecrease ( t = 2. 515,2. 938 ;P < 0. 05 ), while there was no significant difference in SSmax (t = 1. 272,P >0. 05). When the threshold of ADC value was 1. 866 × mm2/s, sensitivity and specificity for determining malignant tumors were 84. 6% (22/26)and 83.3% (20/24). When the threshold of SIdecrease was 40. 33% ,sensitivity and specificity for determining malignant tumors were 88. 5% (23/26)and 75.0% (18/24). In type Ⅰa of TIC,the proportion of benign soft tissue tumor was 3/24 and malignant tumor was 20/26. In type Ⅰb , benign tumor was 14/24 and malignant tumor was 3/26. In type Ⅰc, malignant tumor was 3/26. In type Ⅱ ,benign tumor was 7/24. The diagnostic accordance rate of DWI and PWI were 84. 0% (42/50) and 82. 0% (41/50), respectively. There was no significant difference between them ( x2 = 0. 8, P >0. 05). The accuracies of them were 81.7% , 83. 6% respectively by the area under the ROC curve (AUC). The sensitivity of PWI in diagnosing malignant soft tissue tumors was higher. Conclusions ADC value and SIdecrease are Valllable diagnostic parameters in differentiating benign and malignant soft tissue tumors. The threshold of these parameters for diagnosing malignant soft tissue tumors are 1. 866 × 10-3 mm2/s and 40. 33%, respectively. The type of TIC can help to distinguish malignant tumors from benign tumors, while the SSmax can not. The accuracies of DWI and PWI in the diagnosis of malignant soft tissue tumors are moderate. Compared with DWI, PWI should be selected firstly because of its higher sensitivity in diagnosing malignant tumors.

The study of whole body diffusion weighted imaging application in bone metastasis / 中华放射学杂志

bution probability varied for metastasis of different location. Conclusion WB-DWI was a sensitive method for screening bone metastasis.

The comparative study of MR perfusion-weighted imaging and 1 H-MR spectroscopy in diagnosing soft tissue tumors / 中华放射学杂志

Objective To evaluate multiple magnetic resonance (MR) imaging techniques in the differentiation of benign and malignant soft tissue tumors by comparing different information from MR perfusion-weighted Imaging (MR-PWI) and 1 HMR spectroscopy (1 H-MRS).Methods Forty patients with soft tissue tumors underwent conventional MR imaging,dynamic contrast-enhanced T2*-weighted MR-PWI and 1 H proton MR spectroscopy.The differences of perfusion and 1 H-MRS parameters of benign and malignant tumors were analyzed with t test.Results There was significant difference between benign and malignant tumoral tissues of BF value and Cho/Cr ratio(t=2.531,2.927,P < 0.05),while BV,MTT,Cho,Cr or Lip peak value were not.TIC was different between benign group (Ib) and malignant group (Ia).When the threshold value of BF was 4.35 ml ·100 mg-1·min-1,sensitivity and specificity for determining malignant tumors were 81.8%(18/22),72.2%(13/18),respectively.When the threshold value of Cho/Cr ratio was 3.22,Sensitivity and specificity for determining malignant tumors were 86.4% (19/22),88.9% (16/18),respectively.The abnormal wave crest is detected at 2.0-2.1ppm in 5 malignant tumors (2 malignant schwannoma and 3 malignant fibrous histiocytoma),while the other 35 cases were not.Conclusion The BF value and Cho/Cr ratio were both valuable diagnostic parameters in differentiating benign and malignant soft tissue tumors.TIC was helpful to distinguish malignant tumors from benign tumors,while the sensitivity and specificity of 1 H-MRS in diagnosing malignant soft tissue tumors were both higher.

Investigation on the status of medical students,clinical practice / 中华医学教育探索杂志

Through feedback from questionnaire,relevant problems are summed up,further understanding of the status of medical students' clinical practice is found.then some problems,such as low positivity of students,week didactical consciousness of teachers and inflexibility of practice system,are researched to table some proposals for reformation of clinical practice.