多层螺旋CT血管成像评价左结肠动脉、肠系膜下静脉解剖位置分型在腹腔镜结直肠癌根治术中的应用

Preoperative evaluation of anatomical pattern of left colic artery and inferior mesenteric vein in laparoscopic radical operation for colorectal cancer by using multislice spiral computed tomography angiography

目的:通过多层CT血管成像技术(MSCTA)回顾性分析左结肠动脉(LCA)与肠系膜下静脉(IMV)的解剖位置分型、IMV回流变异情况及IMV于根部以上水平的分支情况。方法:回顾性收集2018年9月至2021年11月92例患者(其中左半结肠癌8例、乙状结肠癌25例、直肠癌59例)的腹部CT增强扫描结果,并进行血管重建与术后录像复习。其中男56例,女36例,中位年龄63(54,72)岁。分别记录肠系膜下动脉(IMA)的分型、LCA/IMV分型及LCA、IMV至IMA根部的距离,IMV的回流汇入位置,IMV于根部以上的分支数量。通过卡方检验分析患者各指标之间与LCA/IMV解剖位置分型的相关关系。结果:MSCTA技术准确判断肠系膜动脉分型情况及LCA与IMV的位置关系准确率达98.91%。其中95.65%(88/92)的病例存在LCA,4例患者LCA缺如;1例患者IMV属于边缘型,85.06%(74/87)的IMV行走于LCA后方,余者走行于前方。IMA根部距LCA的距离平均为(30.11±11.85)mm,距IMV的距离平均为(24.77±10.36)mm。于IMA根部水平LCA走行于IMV外侧者最多,占37.50%(33/88),其次为交叉型(30.68%,27/88)、远侧型(17.05%,15/88)与内侧型(13.64%,12/88)。IMV、LCA边缘型最为少见,仅占1.14%(1/88)。LCA内侧型中,IMV距IMA根部的距离远于其他各型(P<0.05)。LCA远侧型中,LCA距IMA根部的距离远于其他各型(P<0.05)。IMV汇入脾静脉是最常见的回流模式,占55.43%(51/92);34.78%(32/92)的IMV汇入肠系膜上静脉;6.52%(6/92)的IMV汇入SMV与脾静脉交汇位置;3.26%(3/92)的IMV汇入空肠第一支静脉。IMA根部水平以上IMV有2个分支的最多,占51.09%(47/92);1个分支者次之,占25.00%(23/92);3个及以上分支者占20.65%(19/92);0个分支仅占3.26%(3/92)。单因素分析显示,LCA/IMV解剖位置分型与患者性别、身高、体重、BMI、IMV回流方式、IMV与LCA的前后关系等均不相关。结论:MSCTA技术能准确判断IMA、LCA与IMV的解剖位置分型。肠系膜下动、静脉血管解剖变异形式多样,LCA/IMV解剖位置分型与人体相关指标无明确相关关系,因此腹腔镜结直肠癌根治术前通过MSCTA技术了解上述情况十分必要。

Objective:To analyze the intersectional anatomic pattern of left colic artery(LCA)and inferior mesenteric vein(IMV),the draining variation of the IMV and the number of IMV branches above the root level of IMV by using multislice computed tomography angiography(MSCTA)technique retrospectively.Methods:The clinical data including MSCTA images and laparoscopic surgery videos of 92 patients(8 patients with left colon cancer,25 patients with sigmoid colon cancer and 59 patients with rectal cancer)were retrospectively analyzed.All these patients were treated from Sep.2018 to Nov.2021.There were 56 males and 36 females with a median age of 63(54-72)years.The anatomic pattern of inferior mesenteric artery(IMA)and intersectional anatomic pattern of LCA/IMV,the distance between LCA to the root of IMA and the distance between IMV to the root of IMA,the draining pattern of the IMV and the number of the IMV branches above the root of the IMV were recorded and analyzed.Chi-square test was used to analyze the relationship between various indexes of patients and the intersectional anatomic pattern of LCA/IMV.Results:The anatomic pattern of IMA and LCA/IMV were recognized by using MSCTA technique with an accuracy of 98.91%.Among all of the patients,95.65%(88/92)of the cases had LCA,only 4 patients were LCA deficiency,1 case of IMV was marginal type,85.06%(74/87)of the IMV walked behind the LCA,and the rest walked in front of the LCA.The average distance between IMA root and LCA was(30.11±11.85)mm,and the average distance between IMA root and IMV was(24.77±10.36)mm.At the root level of IMA,the majority of LCA walked outside the IMV,accounted for 37.50%(33/88),followed by the LCA overlapping type,which accounted for 30.68%(27/88),the LCA distant type accounted for 17.05%(15/88),and the LCA medial type accounted for 13.64%(12/88).The IMV and LCA marginal type only accounted for 1.14%(1/88).In the LCA medial type,the distance between IMV and the root of IMA was significantly longer than that of the other types.In the LCA distal type,the distance between LCA and the root of IMA was significantly longer than that of other types.The IMV most commonly drained into the splenic vein,accounted for 55.43%(51/92).34.78%(32/92)of the IMV drained into the superior mesenteric vein.6.52%(6/92)of the IMV drained into the confluence of superior mesenteric vein and splenic vein,and 3.26%(3/92)of the IMV drained into the first jejunal vein.Above the root level of IMA,IMV with 2 branches accounted for 51.09%(47/92),followed by 1 branch(25.00%,23/92),3 or more branches accounted for 20.65%(19/92),and 0 branch accounted for only 3.26%(3/92).The intersectional anatomic pattern of LCA/IMV was not associated to gender,height,weight,BMI,the draining pattern of the IMV and LCA walking in front of or behind of IMV.Conclusions:The anatomic variation of IMA and intersectional pattern of LCA/IMV can be accurately recognized by using MSCTA technique.Besides,the anatomic patterns of IMA and IMV are variable,and the intersectional anatomic pattern of LCA/IMV is not associated to body indexes.Therefore,learning the anatomic variation of IMA and intersectional pattern of LCA/IMV before laparoscopic colorectal surgeries is indispensable.