Objective To explore the value of magnetic resonance imaging(MRI)T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI)sequences in evaluating the therapeutic effect of neoadjuvant chemoradiotherapy(nCRT)for advanced rectal cancer.Methods A retrospective analysis was conducted on 124 patients with advanced rectal cancer who received nCRT from November 2020 to November 2023 in Dazhou Integrated TCM&Western Medicine Hospital.All patients underwent radical resection of rectal cancer at 6-8 weeks after the end of nCRT.MRI scans were performed before nCRT and at 6-8 weeks after the end of nCRT.The differences in tumor long and short diameters,signal intensity in tumor(SIT),apparent diffusion coefficient(ADC)and other parameters were measured,and the MRI tumor regression grade was analyzed.Surgery was performed at 3 days after the second examination.The patients were divided into grade 0-1 group and grade 2-3 group according to the postoperative pathological tumor regression grade.The differences of MRI parameters before and after treatment were compared between groups.The consistency of T2WI sequence and DWI sequence in the diagnosis of tumor regression grade after nCRT was analyzed.ROC curve was used to analyze the value of MRI parameters in evaluating the therapeutic effect of nCRT.Results The differences of tumor long diameter,short diameter,SIT and ADC measured by twice MRI examination in grade 0-1 group were increased as compared with grade 2-3 group(P<0.05).MRI detected MRI tumor regression grade 1 in 28 cases(22.58%),grade 2 in 30 cases(24.19%),grade 3 in 31 cases(25.00%),grade 4 in 25 cases(20.16%)and grade 5 in 10 cases(8.06%).Consistency analysis showed that MRI had a sensitivity,specificity,accuracy rate and Kappa value of 92.45%,87.32%,89.51%and 0.788 in evaluating postoperative tumor regression grade.ROC analysis revealed that the AUC of MRI parameters such as differences in tumor long diameter,short diameter,SIT and ADC measured by twice MRI examinations in evaluating the nCRT efficacy ranged from 0.827 to 0.921,and the AUC of combined evaluation was 0.928(P<0.05).Conclusion The combined evaluation of MRI T2WI and DWI sequences can be served as an effective tool for evaluating the therapeutic effect of nCRT for advanced rectal cancer.

Objective To explore the value of magnetic resonance imaging(MRI)T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI)sequences in evaluating the therapeutic effect of neoadjuvant chemoradiotherapy(nCRT)for advanced rectal cancer.Methods A retrospective analysis was conducted on 124 patients with advanced rectal cancer who received nCRT from November 2020 to November 2023 in Dazhou Integrated TCM&Western Medicine Hospital.All patients underwent radical resection of rectal cancer at 6-8 weeks after the end of nCRT.MRI scans were performed before nCRT and at 6-8 weeks after the end of nCRT.The differences in tumor long and short diameters,signal intensity in tumor(SIT),apparent diffusion coefficient(ADC)and other parameters were measured,and the MRI tumor regression grade was analyzed.Surgery was performed at 3 days after the second examination.The patients were divided into grade 0-1 group and grade 2-3 group according to the postoperative pathological tumor regression grade.The differences of MRI parameters before and after treatment were compared between groups.The consistency of T2WI sequence and DWI sequence in the diagnosis of tumor regression grade after nCRT was analyzed.ROC curve was used to analyze the value of MRI parameters in evaluating the therapeutic effect of nCRT.Results The differences of tumor long diameter,short diameter,SIT and ADC measured by twice MRI examination in grade 0-1 group were increased as compared with grade 2-3 group(P<0.05).MRI detected MRI tumor regression grade 1 in 28 cases(22.58%),grade 2 in 30 cases(24.19%),grade 3 in 31 cases(25.00%),grade 4 in 25 cases(20.16%)and grade 5 in 10 cases(8.06%).Consistency analysis showed that MRI had a sensitivity,specificity,accuracy rate and Kappa value of 92.45%,87.32%,89.51%and 0.788 in evaluating postoperative tumor regression grade.ROC analysis revealed that the AUC of MRI parameters such as differences in tumor long diameter,short diameter,SIT and ADC measured by twice MRI examinations in evaluating the nCRT efficacy ranged from 0.827 to 0.921,and the AUC of combined evaluation was 0.928(P<0.05).Conclusion The combined evaluation of MRI T2WI and DWI sequences can be served as an effective tool for evaluating the therapeutic effect of nCRT for advanced rectal cancer.

Objective To investigate metabolic levels of the splenium and genu of corpus callosum(CC)in subacute diffuse axonal injury (DAI)patients,and their longitudinal change in a short time.Methods 12 patients with subacute DAI and 12 gender and age matched healthy controls were enrolled successively in this study.All subjects were scanned with single volume magnetic resonance spectrum(MRS)in two regions of interest(the splenium and genu of CC),and they were reexamined with MRS a month later(31.5 d±6.2 d, 28-43 d).Some metabolite concentrations were calculated quantitatively by using LC-model software and the differences were analyzed.Results The concentrations of NAA in the splenium and genu of CC in subacute DAI patients were decreased significantly compared with those of controls (the genu:t=4.474,P=0.001;the splenium:t=4.231,P=0.001),meanwhile the Cho concentrations were increased significantly (the genu:t=2.509,P=0.031;the splenium:t=2.195,P=0.018).The concentrations of NAA and Cho in the splenium and genu of CC in patients with the follow-up were slightly elevated when compared with those of subacute DAI patients,but the difference had no statistical significance.The concentrations of Cr in the splenium and genu of CC in all subjects had no statistic difference.Conclusion The single volume MRS is sensitive to reflect the metabolic levels of CC in subacute DAI patients.The metabolic levels of CC has no significant change in the short term (about 1 month).

Objective To investigate the correlation between cervical length and preterm birth rate in pregnant women with cervical shortening.Methods A group of pregnant women who had had two children in our hospital were included.Both lengths of 24-28 weeks were measured by transvaginal ultrasound during both pregnancies.According to the length of the cervix measured by the vagina during the first trimester and whether it is full-term production,it can be divided into the cervical shortening full-term group,the cervical shortening premature delivery group,the normal cervical full-term group (control group),and the clinical and ultrasound measurements are statistically analyzed.Results The cervical shortening in the preterm group and the cervical shortening in the full-term group were more likely to have cervical reduction in the second pregnancy than in the normal cervical full-term group (P ＜ 0.05).The rate of spontaneous preterm birth in the second trimester of the cervix shortened in the preterm group was the highest (P ＜ 0.05).There was no significant difference in the preterm birth rate of the second pregnancy between the normal uterine cervix group and the cervical shortened term group (P ＞ 0.05).Conclusions In the pregnant women with cervical shortening,cervix shortening occurs.Whether the first child is full-term is the key factor in predicting the second premature birth rate.

Objective To investigate microstructure of the corpus callosum(CC) in subacute diffuse axonal injury(DAI) patients and its the longitudinal change in a short time.Methods 21 patients with subacute DAI were enrolled successively in this study,and in which 12 patients were reexamined followed-up with DTI a month later (31.5 d±6.2 d,28-43 d),and then 12 gender and age matched healthy controls were recruited.The DTI data of all subjects were acquired on at a 3.0T MRI.The CC was divided into six segments:the genu, rostral mid-body, anterior mid-body,posterior mid-body, isthmus, and splenium.ROIs were placed on each segment on color fractional anisotropy (FA) maps in the midsagittal plane manually.The FA and apparent diffusion coefficient(ADC) values of each subregion of CC were measured and compared between subacute DAI group,follow-up group and controls respectively.In addition,a related analysis between DTI parameters of each sub-region of CC and GCS on admission was done by using person correlation analysis.

Objective To explore the application value of SWI in hyperacute ischemic cerebral infarction.Methods 40 patients with massive hyperacute ischemic cerebral infarction in middle cerebral artery (MCA)territory were enrolled successively who underwent MR imaging with conventional MRI,DWI,MRA and SWI sequence immediately.The MR images were analyzed by two senior neuroimaging physicians and the results were recorded.The number of thrombosis at MCA showed on SWI was compared with that showed on conventional MR sequence and the number of MCA stenosis or occlusion showed on MRA,the length of thrombosis and the number of cases with veins increased in infarct area were also compared.Results The number of thrombosis at MCA showed on SWI was more than that showed on conventional MR sequences significantly (23 vs 12,χ2 =6.146,P =0.013),and was lower than that showed on MRA (23 vs 24,χ2 =0.052, P =0.820)slightly.Thrombosis at MCA trunk and its small branches were found in the meantime in 2 cases .The length of thrombosisshowed on SWI was longer than that showed on conventional MRI sequences (25.7 mm±9.4 mm vs 14.6 mm±8.5 mm,t=14.395,P =0.000), significantly and the number of patient with veins increased in infarct area showed on SWI was more than that showed on conventional MR sequences (21 vs 12,χ2 =4.1 78,P =0.041)significantly.Conclusion SWI has usefull application value in patients with hyperacute massive ischemic cerebral infarction.