背景:最近的研究描述了Riolan弧(AoR)穿过肠系膜下静脉(IMV)的发现。然而,AoR通常有一个中间路线,这种变异的AoR解剖过程以及在前切除术中脾屈时保留其临床重要性仍存在争议。
方法:经机构批准(QA-5775),胰腺下水平穿过IMV的血管的放射学鉴定和标测,当存在时,在一家机构(Westmead医院,新南威尔士州,澳大利亚)。回顾性回顾了2018年进行的一百次连续的计算机断层摄影(CT)肠系膜血管造影,以确定是否存在水平穿过IMV的血管。使用3D重建来绘制其过程,以了解其起源和完整过程。基线特征,包括人口统计和合并症数据,是从医疗记录中获得的。
结果:关于3D肠系膜血管造影重建,98例中有11例(11.2%)存在穿过IMV前方的血管。由于该血管的存在不确定,因此排除了2例。11例患者中有8例(72.7%)为男性,平均年龄为49.3岁(范围:21-80岁)。两组之间的年龄和合并症没有统计学上的显着差异。重要的是,在所有11个案例中,有一条动脉血管穿过源自SMA的IMV,并与IMA或IMA的分支连通,明确证明这艘船的定义是AoR。
结论:这项3D肠系膜血管造影绘图研究明确表明,水平横穿IMV前方和胰腺下方的血管是从SMA到IMA的动脉血管,根据定义,Riolan之弧。当存在时,在前切除术的脾屈时识别和保留该侧支动脉血管对于降低术后肠缺血的风险可能很重要.
BACKGROUND: Recent studies have described the finding of the Arc of Riolan (AoR) crossing the inferior mesenteric vein (IMV) seen during high ligation of IMV while performing minimally invasive colectomies. However, the AoR usually has a medial course, and this variant AoR anatomic course and the clinical importance of its preservation during splenic flexure takedown in anterior resection remains controversial.
METHODS: After institutional approval (QA-5775), radiological identification of and mapping of the vessel horizontally crossing the IMV under the pancreas, when present, was performed at a single institution (Westmead Hospital, New South Wales, Australia). One hundred consecutive computed tomographic (CT) mesenteric angiograms conducted in 2018 were reviewed retrospectively to determine the presence of a vessel horizontally crossing the IMV. 3D reconstructions were used to map out its course to understand its origin and full course. Baseline characteristics, including demographic and comorbidity data, were obtained from the medical record.
RESULTS: On 3D mesenteric angiogram reconstructions, a vessel crossing anterior to the IMV was present in 11 of 98 cases (11.2%). Two cases were excluded as the presence of this vessel was indeterminate. Eight of 11 patients (72.7%) were male, and the mean age was 49.3 years (range: 21-80 years). There was no statistically significant difference in age and comorbidities between the groups. Importantly, in all 11 cases, there was an arterial vessel crossing the IMV originating from the SMA and communicating with the IMA or a branch of the IMA, proving definitively that this vessel was by definition the AoR.
CONCLUSIONS: This 3D mesenteric angiogram mapping study has shown definitively that the vessel horizontally crossing anterior to the IMV and inferior to the pancreas is an arterial vessel from the SMA to IMA, and by definition the Arc of Riolan. When present, identification and preservation of this collateral arterial vessel during splenic flexure takedown in anterior resection may be important in reducing the risk of post-operative bowel ischaemia.