CT And MRI Perfusion Imaging Research Of The Rectal Malignant Tumor

part1:Perfusion Imaging Research of CT and MRI of the Rectal malignant TumorObjective:To explore the characterics of common malignant rectal neoplasm of rectum of time density curve (TDC), and evaluate the application value of CT perfusion (CTP) parameters in preoperative evaluation of malignant rectal tumor.Materials and Methods:Patients with malignant tumor in the rectum were hospitalized in Tianjin union medical centre during2013March to2014March.39cases were choosed from which in a random,underwent enhanced CT and CTP examination, which included33rectal cancer,6cases of rectal stromal tumors. All patients didn’t receive chemotherapy; check operation excision within2weeks after examination and successfully obtained specimens and pathological diagnosis; All images of CT are clear without artifact. In33cases of rectal cancer (6cases of highly differentiated adenocarcinoma,14cases of moderately differentiated adenocarcinoma,13cases of poorly differentiated adenocarcinoma),6cases of stromal tumor (4cases were highly malignant,2cases were moderate malignant).20Male cases,19female cases, age28～81years, average54.6years old. Firstly, determine the tumor morphology of TDC, two physician measuring tumor blindedly measureed perfusion parameters of tumor (BF, BV, MTT, PS) and compared with the consistency and reproducibility of the measured results,. The perfusion parameters of the different degrees of differentiation for between rectal cancer, rectal cancer and stromal tumor rectal cancer and stromed tumor were compared between the group.Results:The rectum cancer TDC were divided into5types:type I to speed up and slow lifting type, type II to speed up and slow down type, type III for speed up and speed slow drop type, type IV to speed up and speed-platform type, type V to speed up platform;100%of rectal stromal tumors curves are shown as quick lift platform; The type V curve was not found in the high differentiated adenocarcinoma group. Ⅰ～Ⅳ type TDC distribution had no difference in the low and moderate differentiated cancer. The consistency of CT perfusion parameters measurement and good repeatability was good. In different differentiation of rectal cancer group, differences between BV and MTT was not significant (P>0.05), BF, PS mean gradually ascended with the degree of differentiation decreasing, there was a significant difference (P<0.05). Mean values of BF, BV and PS in rectal cancer were higher than stromal tumors. There were significant differences (P<0.05), There was no significent difference of MTT between rectal cancer and stromal tumor (P>0.05).Conclusion TDC of the rectal cancer and stromal tumor had them characteristic in respects.lt was worthy that the difference of the mean values of BF,BV,andPS in the rectal cancer and stromal tumor for making a diagnosis and differential diagnosis PART2Imaging Research of MRI perfusion of the Rectal cancerObjective:To study the analysis of quantitative and semi-quantitative in the perfusion imaging in the rectal cancer, compared the similar, the advantage and defect between the CT and MR perfusion imaging. To study the application value of magnetic resonance perfusion imaging in the preoperative examination rectal cancer.Objects and methods:Patients with rectal cancer were hospitalized in Tianjin union medical centre during2013March to2014March.They were made enhanced MRI and PWI examination, including21cases of rectal cancer. Rectal cancer in21cases (including6cases of highly differentiation,9cases of the moderate differentiation,3cases of low differentiated), the same group cases were Dukes stage (stage A4cases, stage B6cases, stage C7cases, stage D4cases)14male cases,10female cases, age24～92years old, average age is56years old. Firstly, semi quantitative TICs analysis and classification, semi-quantitative parameters were compared with peak time (Tpeak), peak (SI), signal enhancement ratio (E) and the maximum signal enhancement ratio (Emax), in rectal cancer and normal intestinal tissue, benign and malignant lymph nodes around the rectal cancer, not the same degree of pathological differentiation, compared the difference between different Dukes stages. Then contrast-time curve drawing (CTCs) of the quantitative analysis were made, the volume transfer constant (Ktrans) and the rate constant (Kep) and other parameters were different histological differentiation and Dukes staging is different between groups.Results：The rectal TICs were divided into4types:type Ⅰ，speeding up and slow lifting to the platform, type Ⅱ speeding up and platform, type Ⅲ speeding up and slow down to the platform, type Ⅳ speed ascending to the platform. Well differentiated adenocarcinoma without type Ⅳ curves. It was a significant difference for the value of Tpeak, SIpeak, E,Emax from rectal cancer compared with the normal rectal wall,(P<0.05). Rectal cancer with the reduction in the degree of differentiation, Tbegin and Tpeak has a extended trend gradually, peak increased, gradually there was no significant difference (P<0.05). Early maximum signal enhancement ratio and signal enhancement rate had no significant difference (P>0.05). The peak time of different Dukes stage rectal cancer patients in stage C TIC parameter (Tpeak) is less than the rest of the time, and there were significant differences (P<0.05). Analysis Yuban quantitative parameters by single factor variance, there was no significant difference (P>0.05). Differences between benign and malignant nodules surrounding the rectum semi-quantitative parameters,which was not significant (P>0.05). Analysis of Ktrans value and Kep value increased with the malignant degree of quantitative pathological increase, but the difference was not significant (P>0.05). With the Ktrans value and Kep value of the tumor increasing, it decreased in stage D, there was a significant difference (P<0.05).Conclusion: TICs and TDC curve are similar, but different slightly. Research shows that along with the tumor differentiation and preoperative staging, perfusion parameters have certain difference. It had a good consistency between TICs and TDC.Application of DCE of rectal cancer before operation, which could describe hemodynamic that contrast agent enters and exits the tumor comprehensively, thus providing the possible of observation of the attributes fron tumor blood vessels. Not only it can display the morphological characteristics of lesions, but also part of the reaction was generally blood circulation and interstitial constitution as well as the risk of lymph node metastasis and recurrence. Some value of TICs can be used in the differential diagnosis of tumor mass between the rectal cancer and the submucosa tumor. It is very important for PWI to make a diagnosis and treatments of rectal cancer, Which can be used as an important supplementary means for clinical preoperative evaluation.