Objective To evaluate the value of MR and CT examinations in the diagnosis of nasopharyngeal carcinoma (NPC) and compare 2008 staging system with 1992 staging system and 2002 UICC staging system for NPC. Methods MR and CT images of seventy-six cases with NPC were studied. According to 2008 staging system and taking MR as a standard, differences between these two examinations were evaluated under the new NPC staging system, and three staging system were compared by MR findings. Results MR was inconsistent with CT in eveluating invasion of medial pterygoid muscle(22,24 cases), lateral pterygoid muscle( 15, 11 cases), skull base(35, 32 cases) and intracranial fossa( 11,6 cases), but no statistical diffence existed ( P ＞ 0. 05 ). There were statistical difference ( P ＜ 0. 05 )between MR and CT in determining invasion of parapharyngeal space( 50, 61 cases), retropharyngeal lymph node metastasis(48, 23 cases), stage T1 (18, 11 cases), T2 (15, 22 cases), N0 (18, 24 cases) and N1(33, 27 cases) with differences of 11 cases, 25 cases, 7 cases, 7 cases, 6 cases and 6cases respectively.For invasion of parapharyngeal space, CT showed 11 cases more than MR while 5 cases were comfirmed as compression by local tumor and 6 cases were proved as retropharyngeal lymph node metastasis according to MR. For retropharyngeal lymph node metastasis, MR presented 25 cases more than CT. These two reasons above mainly caused the differences of T-staging and N-staging. For 2008 staging system, when compared with 1992 staging system, there were 9 cases upstaging and 1 case downstaging in T classification, 16 cases upstaging in N classification, and 15 cases upstaging and 1 case downstaging in clinical classification; and when compared with 2002 UICC staging system, there were 7 cases, 10 cases and 12 cases upstaging in T,N, and clinical staging respectively. Conclusions Compared with MR examination which was regarded as standard by 2008 staging system of NPC, there were some differences in demonstrating invasion of parapharyngeal space and retropharyngeal lymph node metastasis by CT. Compared to 1992 staging system and 2002 UICC staging system, 2008 staging system mainly made T and N classification of tumor upstage,resulting in upstaging in clinical classification.

Objective To evaluate 3.0T MR diffusion weighted imaging (DWI) and ADC value in diagnosis of different pathological types and grades of malignant renal tumors. Methods DWI images of 66 patients of malignant renal tumors proved pathologically were retrospectively reviewed. ADC values of tumors and the corresponding areas of lateral normal renal parenchyma were measured and analyzed statistically. Results There was significant difference between the mean ADC value of malignant renal carcinomas ([1.653±0.598]×10~(-3) mm~2/s) and that of normal renal parenchyma ([2.305±0.218]×10~(-3) mm~2/s, P<0.001). ROC curve showed that taking ADC value of lower than 2.0×10~(-3) mm~2/s as a threshold for diagnosing renal malignant tumor, the specificity, sensitivity and accuracy was 93.94%, 71.21% and 82.58%, respectively. Statistical differences were found between clear cell carcinoma and non-clear cell carcinoma (P=0.001), as well as clear cell carcinoma grade Ⅰ and Ⅲ (P=0.002), grade Ⅱ and Ⅲ (P=0.004) respectively. However, no statistical difference was observed between grade Ⅰ and Ⅱ (P=1.000). Conclusion 3.0T MR DWI can be used in diagnosis of malignant renal tumors, and ADC value may help to differentiate the pathological type and grade.

Objective To investigate the value of DWI before treatment on predicting sensitivity of concurrent chemoradiation in nasopharyngeal carcinoma.Methods Seventy patients with nasopharyngeal carcinoma proved by nasopharyngoscope and biopsy pathology conducted DWI before concurrent chemoradiation and reexamined on receiving dose of 50 Gy.The mean, maximum and minimum ADC value of tumor were measured on DWI and maximum area of tumor before and during treatment ( on dose of 50 Gy) was delineated to calculate the tumor regression rate ( RS0-50 ).The patients were classified into three groups according to the RS0-50 as sensitive, moderate, and resistant therapeutic effect.Patients were classified into different groups according to the pathologic type and clinical stage respectively .Spearman correlation analysis was used between RS 0-50 and ADC values of all tumors , different pathologic types and clinical stages , respectively.ROC was used to evaluate the cutoff and value of ADC which had highest correlation to RS0-50 on predicting therapeutic effect.Results DWI of 3 patients were excluded due to obvious swallow artifact which influenced the measurement , and finally 67 patients were included in this study, with pathological type of nonkeratinized differentiated undifferentiated carcinoma in 49 cases, nonkeratinized undifferentiated carcinoma in 18 cases, clinical T1 stage in 7 cases, T2 in 14 cases, T3 in 17 cases and T4 in 29 cases.During treatment , there were 13 cases with sensitive therapeutic effect , 42 cases with moderate therapeutic effect and 12 cases with resistant therapeutic effect.RS0-50 [ ( 65.6 ± 3.1) %] showed mildly and moderately negative correlation to mean ADC [(1.06 ±0.19) ×10 -3 mm2/s] and maximum ADC [(1.29 ±0.33) ×10 -3 mm2/s] respectively ( r =-0.276, P =0.024 and r =-0.434, P=0.001, respectively).ROC showed when setting threshold at maximum ADC value of lower than 1.06 ×10 -3 mm2/s for predicting sensitive therapeutic effect , the specificity , sensitivity , and accuracy was 69.2%(9/13), 88.9%(48/54) and 85.1% (57/67), respectively, and when setting threshold at maximum ADC value of higher than and equal to 1.30 ×10 -3 mm2/s for predicting resistant therapeutic effect, the specificity, sensitivity, and accuracy was 75.0% (9/12), 65.5% (36/55) and 67.2%(45/67), respectively.Conclusion Pretreatment maximum ADC value were able to predict the tumor regression rate and sensitivity of concurrent chemoradiation in nasopharyngeal carcinoma .

Objective To evaluate 3.0T MR diffusion weighted imaging (DWI) and ADC value in diagnosis, histological grade, tumor staging and short-time therapeutic outcome of clear cell renal cell carcinomas (CCRCC). Methods DWI of 51 patients of CCRCC confirmed with surgery and pathology were retrospectively reviewed. ADC values of tumors and the corresponding areas of lateral normal renal parenchyma were measured. Taking ADC value at 1.8×10~(-3) mm~2/s as a cut-off value, the patients were divided into two groups. The tumors' histological grade, T-staging, clinical staging, tumor short-term control rate within 1 year follow-up were compared between the two groups with statistical test. Results Statistical difference of ADC value was observed between CCRCC ([1.778±0.582]×10~(-3) mm~2/s) and those of normal renal parenchyma ([2.314±0.223]×10~(-3) mm~2/s) (P<0.01). ADC values of 24 patients were less than 1.8×10~(-3) mm~2/s and those of 27 patients were more than or equal to 1.8×10~(-3) mm~2/s. There were statistical differences in histological grade, T-staging, clinical staging, tumor short-term control rate within 1 year follow-up between the two groups (P＜0.01). Conclusion 3.0T MR DWI can accurately differentiate CCRCC from normal renal parenchyma. Quantitative analysis of ADC value is helpful to evaluate the histological grade, tumor staging and short-term therapeutic outcome of CCRCC.

Objective:To investigate the application of the 7E teaching model (i.e., Elicit, Engage, Explore, Explain, Elaborate, Evaluate, and Extend) combined with standardized patients (SP) in nursing practice teaching for general surgery.Methods:A total of 80 nursing students who were assigned to Department of General Surgery in our hospital were selected and divided into control group and observation group according to the order of admission, with 40 students in each group. The students in the control group received traditional teaching, while those in the observation group received the 7E teaching model combined with SP. Theoretical and practical operation scores were assessed for both groups, and the scores of non-technical skills were compared between the two groups. SPSS 22.0 was used to perform the t-test. Results:Compared with the control group, the observation group had significantly better scores of theoretical assessment (89.36±2.13 vs. 87.64±2.07, P<0.05) and practical operation (92.07±4.33 vs. 85.19±3.46, P<0.05). The observation group had significantly higher scores of non-technical skills (humanistic care ability, ability to stimulate learning interest, communication ability with patients, depth of the understanding of diseases and nursing ability, knowledge extension ability, team collaboration ability, clinical thinking ability, and clinical decision-making ability) than the control group ( P<0.05). Conclusion:The 7E teaching model combined with SP in nursing practice teaching for general surgery can better enhance the theoretical and practical abilities of nursing interns and help to improve the level of non-technical skills.

Objective To evaluate the value of parameters derived from intravoxel incoherent motion diffusion?weighted magnetic resonance imaging in differentiating histopathological subtypes of renal cell carcinoma ( RCC) . Methods Between May 2014 and December 2015, a total of 69 patients who were surgically and pathologically diagnosed as renal cell carcinoma were recruited for the study. We examined 61 clear cell RCC ( ccRCC) , and 8 non?clear cell carcinoma ( non?ccRCC, including 7 chromophobe RCC and 1 papillary RCC ) . All the ccRCC were divided into well differentiated group ( n = 46 ) , moderately differentiated group (n=8), and poorly differentiated group (n=7). In addition to routine renal magnetic resonance imaging examination performed on a 3. 0?Tesla MR system, all patients were imaged with axial intravoxel incoherent motion diffusion?weighted imaging. Using biexponential model, we calculated the diffusion coefficient ( D) , pseudodiffusion coefficient ( D?) , and perfusion fraction ( f) . Results The D and f values of the ccRCC were higher (each P<0.05) than that for non?ccRCC [D (1.29±0.30)×10-3mm2/s, D?(42.92±20.21)×10-3mm2/s, and f (35.71±6.61)% versus D (0.78±0.23)×10-3mm2/s, D?(32.60±11.33)×10-3mm2/s, and f (21.52±8.44)% ]. In the well differentiated group of ccRCC, we found D of (1.36±0.29)×10-3mm2/s, D?(38.39±18.51)×10-3mm2/s, and f (36.40±6.96)%. The D, D?, f values of moderately differentiated lesions were (1.10±0.24)×10-3mm2/s, (59.90±20.23)×10-3 mm2/s, and (32.88±4.02)%, respectively, those of the poorly differentiated group were (1.03±0.16)×10-3mm2/s, (53.28±18.74)×10-3mm2/s, and (34.42±6.21)%. The well differentiated group of ccRCC showed a higher D value than the moderately differentiated and poorly differentiated groups ( each P<0.05) . D? values were significantly lower for the well differentiated group than for the moderately differentiated group (P<0.05). The sensitivity and specificity of D values were 90. 2% and 87. 5% when focusing on the differentiation of ccRCC. For the diagnosis of ccRCC, the sensitivity and specificity of f values were 98. 4% and 75. 0%, respectively. Conclusions IVIM?DWI can provide certain reliable value in evaluating pathological subtype and differentiation degree of renal cell carcinomas. D and f values are useful to distinguish ccRCC from non?ccRCC. D value is also promising for estimating the differentiation degree of ccRCC, and to indicate the biological behavior of RCC.

Objective To evaluate the value of parameters derived from intravoxel incoherent motion diffusion?weighted magnetic resonance imaging in differentiating histopathological subtypes of renal cell carcinoma ( RCC) . Methods Between May 2014 and December 2015, a total of 69 patients who were surgically and pathologically diagnosed as renal cell carcinoma were recruited for the study. We examined 61 clear cell RCC ( ccRCC) , and 8 non?clear cell carcinoma ( non?ccRCC, including 7 chromophobe RCC and 1 papillary RCC ) . All the ccRCC were divided into well differentiated group ( n = 46 ) , moderately differentiated group (n=8), and poorly differentiated group (n=7). In addition to routine renal magnetic resonance imaging examination performed on a 3. 0?Tesla MR system, all patients were imaged with axial intravoxel incoherent motion diffusion?weighted imaging. Using biexponential model, we calculated the diffusion coefficient ( D) , pseudodiffusion coefficient ( D?) , and perfusion fraction ( f) . Results The D and f values of the ccRCC were higher (each P<0.05) than that for non?ccRCC [D (1.29±0.30)×10-3mm2/s, D?(42.92±20.21)×10-3mm2/s, and f (35.71±6.61)% versus D (0.78±0.23)×10-3mm2/s, D?(32.60±11.33)×10-3mm2/s, and f (21.52±8.44)% ]. In the well differentiated group of ccRCC, we found D of (1.36±0.29)×10-3mm2/s, D?(38.39±18.51)×10-3mm2/s, and f (36.40±6.96)%. The D, D?, f values of moderately differentiated lesions were (1.10±0.24)×10-3mm2/s, (59.90±20.23)×10-3 mm2/s, and (32.88±4.02)%, respectively, those of the poorly differentiated group were (1.03±0.16)×10-3mm2/s, (53.28±18.74)×10-3mm2/s, and (34.42±6.21)%. The well differentiated group of ccRCC showed a higher D value than the moderately differentiated and poorly differentiated groups ( each P<0.05) . D? values were significantly lower for the well differentiated group than for the moderately differentiated group (P<0.05). The sensitivity and specificity of D values were 90. 2% and 87. 5% when focusing on the differentiation of ccRCC. For the diagnosis of ccRCC, the sensitivity and specificity of f values were 98. 4% and 75. 0%, respectively. Conclusions IVIM?DWI can provide certain reliable value in evaluating pathological subtype and differentiation degree of renal cell carcinomas. D and f values are useful to distinguish ccRCC from non?ccRCC. D value is also promising for estimating the differentiation degree of ccRCC, and to indicate the biological behavior of RCC.

Objective To investigate the imaging appearance of CT and MRI in retroperitoneal dedifferentiated liposarcoma ( DDL ) based on pathological findings. Methods Twelve patients with retroperitoneal DDL ( 13 lesions) who were surgically and pathologically confirmed were retrospectively collected in the Cancer Hospital of Chinese Academy of Medical Sciences. The correlation of CT and MRI features with histopathologic findings was analyzed. Results The CT and MRI images of retroperitoneal DDLs were large, heterogeneous soft?tissue masses, mostly lobulated (30.8%, 4／13) or multinodular (46.2%, 6／13), invading adjacent anatomic structures (46.2%, 6／13).The lesions contained different proportions of fatty and non?fatty components, and usually with clear boundaries. The CT images of dedifferentiated components showed non?fatty masses of soft tissue density or mixed density, among which ground?glass nodules may be related to mucinous components. Occasionally calcification or ossification was seen (45.5%, 5／11). The contrast?enhanced CT and MRI images of non?fatty components commonly showed intense heterogeneous enhancement ( 84.6%, 11／13), central cystic changes and necrosis ( 61.5%, 8／13 ), pathologically corresponding to multiple types of soft tissue sarcomas without significant specificity. The well?differentiated components were fatty masses with irregular fibrous septa or soft tissue nodules, which is pathologically corresponding to well differentiated liposarcoma. Lymph node or distant metastasis was rare. Conclusions The imaging manifestations of retroperitoneal DDLs are diverse and closely related to the proportion and distribution of different components. CT, MRI and contrast?enhanced imaging has a certain diagnostic value for retroperitoneal DDLs.

Objective To investigate the imaging appearance of CT and MRI in retroperitoneal dedifferentiated liposarcoma ( DDL ) based on pathological findings. Methods Twelve patients with retroperitoneal DDL ( 13 lesions) who were surgically and pathologically confirmed were retrospectively collected in the Cancer Hospital of Chinese Academy of Medical Sciences. The correlation of CT and MRI features with histopathologic findings was analyzed. Results The CT and MRI images of retroperitoneal DDLs were large, heterogeneous soft?tissue masses, mostly lobulated (30.8%, 4／13) or multinodular (46.2%, 6／13), invading adjacent anatomic structures (46.2%, 6／13).The lesions contained different proportions of fatty and non?fatty components, and usually with clear boundaries. The CT images of dedifferentiated components showed non?fatty masses of soft tissue density or mixed density, among which ground?glass nodules may be related to mucinous components. Occasionally calcification or ossification was seen (45.5%, 5／11). The contrast?enhanced CT and MRI images of non?fatty components commonly showed intense heterogeneous enhancement ( 84.6%, 11／13), central cystic changes and necrosis ( 61.5%, 8／13 ), pathologically corresponding to multiple types of soft tissue sarcomas without significant specificity. The well?differentiated components were fatty masses with irregular fibrous septa or soft tissue nodules, which is pathologically corresponding to well differentiated liposarcoma. Lymph node or distant metastasis was rare. Conclusions The imaging manifestations of retroperitoneal DDLs are diverse and closely related to the proportion and distribution of different components. CT, MRI and contrast?enhanced imaging has a certain diagnostic value for retroperitoneal DDLs.

Objective: To evaluate the diagnostic value of thin-slice CT navigation combined with cytology in routine preoperative bronchoscopy of peripheral pulmonary lesions and compare the diagnostic effects of different cytological sampling methods. Methods: The clinical data of peripheral lung cancer patients with preoperative bronchoscopy and cytology sampling guided by thin-slice CT from May 2015 to July 2016 in Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. The diagnostic accuracy, sensitivity and specificity of different cytological sampling methods for peripheral pulmonary lesions guided by thin-slice CT were compared, the factors affected the diagnostic sensitivity were analyzed, and the complications induced by these methods were observed. Results: The diagnostic sensitivity of thin-slice CT navigation combined with bronchoalveolar lavage for peripheral pulmonary lesions was 39.1%, and the positive diagnosis rate was 35.1%. The diagnostic sensitivity of thin-slice CT navigation combined with cell brush for peripheral pulmonary lesions was 51.7%, and the positive diagnosis rate was 46.4%. The diagnostic sensitivity of bronchoalveolar lavage combined with cell brush for peripheral pulmonary lesions was 57.5%, and the positive diagnosis rate was 51.5%. The positive diagnosis rate between brush sampling and bronchoalveolar lavage was statistically different (P=0.01). No significant difference was observed in the diagnostic rate between cell brush and cell brush combined with bronchoalveolar lavage (P=0.06). The factors affected diagnostic sensitivity of brush included the lesion location, size, and the relationship between the lesion and bronchial (all P<0.05). When the size of the peripheral lung lesion >2 cm, the diagnostic sensitivity of thin-slice CT navigation combined with cell brush for peripheral pulmonary lesions was 73.6%. Its positive diagnosis rate was 68% and the specificity was 100%, respectively. Two cases of mild bleeding were observed, and hemorrhage was terminated by conservative treatment. Conclusion Preoperative thin-slice CT navigation combined with cytological examination is an effective method for the diagnosis of peripheral pulmonary lesions, and the diagnostic efficiency of cell brush is higher than that of bronchoalveolar lavage, especially for the lesion size >2 cm.