CT/MRI Imaging Diagnosis Of Colorectal Liver Metastases

Objective: This study intends to analyze the distribution of hepatic metastases in different sites of colorectal cancer to confirm the hypothesis of "portal streamline effect",analyze the relationship between colorectal cancer and the distribution of metastases in different sites,and Analyze the relationship between blood supply in different sizes of liver metastases.To investigate the CT/MRI features of colorectal cancer with a single hepatic metastasis.Improve the understanding of imaging features of liver metastases and reduce the misdiagnosis rate.Methods: Retrospective analysis was used to continuously collect 91 cases of colorectal liver metastases(CRCLM)from the first affiliated hospital of Guangxi Medical University from June 2010 to January 2018 with multi-slice spiral CT examination and complete clinical data.The location of the primary tumor,the distribution,size,number of metastatic tumors,CT values of the metastatic tumors at each stage,and the method of enhancement,and the portal vein approach of the inferior mesenteric vein(IMV)in patients with left colon cancer.The distribution of hepatic lobes,the number of hepatic metastases,and the differences in methods of hepatic artery augmentation(AEF)between different sizes were analyzed.Data was analyzed by SPSS 17.0 statistical software.Results: 1、 There was significant difference in the detection rate of hepatic metastases at each stage of CT enhancement(P<0.05).The total number of lesions detected at the portal phase was higher than that of plain scan,arterial phase and delayed phase.Especially for small liver metastases,there was no difference in the detection of liver metastases >3cm.2、 Except for the average group,there was no statistically significant difference in the distribution of hepatic metastases between the left and right colons and the lower rectum(P=0.216).When the primary tumor was in the left colon,there was a statistically significant difference in the distribution of metastatic tumors between the left and right hepatic lobes(P=0.042).The distribution of metastatic tumors was different in the left semi-colonic IMV infusion,and when the IMV was imported into the SPV The left lobe of hepatic metastases was more common than the left hepatic lobe.When IMV entered the junction of SPV and SMV,there was no significant difference in the distribution of left and right lobes of liver metastases.When IMV was introduced into SMV,the advantage of right lobe of liver metastases was more common.When the primary lesion was in the right colon,there was a statistically significant difference in the distribution of metastatic tumors between the left and right lobes(P=0.001),which was mainly distributed in the right lobe of the liver.When the primary tumor was located in the lower rectum,there was no significant difference in the distribution of metastases between the left and right hepatic lobes(P=0.763).3、 There was a statistically significant difference in the enhancement of different types of hepatic metastases(P=0.00).Fast-forward and fast-out were more common in >3cm liver metastasis,and fast-forward and slow-out were more common in ≤3cm liver metastases.4、 There was no significant difference in the portal phase enhancement of colorectal hepatic metastasis between different sizes(P=0.408).In the>3cm group,lesion arterial phase enhancement and AEF were higher than the ≤3cm group lesions,the difference was statistically significant(P= 0.03,P=0.00).5、 the diagnosis of a single liver metastases is more difficult,the diagnosis of 25 cases in this group,in addition to the common CT image characteristics of liver metastases,the following signs can also be seen: the lesion diameter is larger,mostly in the outer edge of the liver,liver lesions can be There is a change in the envelope depression.Conclusions:1、Colorectal liver metastasis tumors have different detection rates in different phases of CT scan,and detection of portal vein lesions is more advantageous,especially for tiny liver metastases.2 、 The distribution of colorectal liver metastases is consistent with the "portal streamline effect",SMV blood flow easily into the right lobe of the liver,SPV blood flow easily into the left lobe of the liver.Lower rectal cancer liver metastases were randomly distributed.3、> 3cm and ≤ 3cm compared colorectal liver metastases,blood supply composition ratio between the two groups is not the same,> 3cm group hepatic metastases to the hepatic artery blood supply.4、 The single hepatic metastatic tumor is easily confused with other liver space-occupying lesions.Grasp its characteristics and can improve the diagnostic accuracy.