目的　为内窥镜下十二指肠乳头括约肌切开术( EST) 与内镜乳头气囊扩张术 (EPBD)取结石术提供形态学依据。 方法　(1)20例乳胶动脉血管灌注胰腺十二指肠标本，解剖观测十二指肠大乳头血供的来源、数量，营养血管起始处直径、至Vater壶腹和十二指肠大乳头开口的距离。前、后弓最凸处与十二指肠内缘、肝胰壶腹、十二指肠大乳头的距离。(2)按胰十二指肠正常解剖学位置摆放，以十二指肠大乳头的开口为圆心，十二指肠大乳头背面纵轴为12~6点轴，横轴为9~3点轴，顺时针依次定点，观察动脉分布特点。  结果　(1) 胰十二指肠前、后动脉弓各发出2支营养血管至十二指肠大乳头。前弓2支血管起始处直径分别为（1.3±0.1、1.0±0.2）mm，至Vater壶腹和十二指肠大乳头开口的距离分别为（5.7±0.6、6.0±0.4）mm、（16±0.9、16±1.5）mm。后弓2支血管起始处直径分别为（0.62±0.02、0.98±0.06）mm，至Vater壶腹和十二指肠大乳头开口的距离分别为（20±1.5、16.4±0.4）mm、（25±1.2、19.2±0.6）mm。前、后弓最凸处与十二指肠内缘、肝胰壶腹的距离分别为（4.05±0.1、3.1±0.15）mm、（10.5±1.5、13.2±1.6）mm。(2)十二指肠大乳头前壁第1支血管位于9~10点钟方位，第2支位于2~3点钟方位；后壁第1支动脉血管位于8~9点钟方位，第2支位于4~5点钟方位；8~10点钟方位血管最集中，2~5点钟方位血管次之，11~1、6~7点钟方位血管供应最少。  结论　临床EST Oddi括约肌切开和EPBD取结石时，易损伤十二指肠大乳头血管，需小心保护。EST可在11~1或6~7点钟方位行乳头切开。

 Objective    To provide exact and reliable morphological data for the operation of endoscopic sphincterotomy (EST).    Method   (1) 20 cadeveric duodenum and pancreas were perfused with latex.  (2)The resource, number, diameter, branches of all carunculae major arteries of these specimens and the distance from vascular origin to Vater bulb, the inner margin of duodenum and carunculae major were observed.         Results   (1) Carunculae major arteries originated from the anterior and posterior arterial arches, and each had two branches. The diameter of the two branches of the anterior carunculae major artery was (1.3±0.1) mm and (1.0±0.2) mm. The distance from the vascular origin of the two branches to the Vater’s ampulla, the inner margin of duodenum and carunculae major was (5.7±0.6) mm and (6.0±0.4) mm, (8.7±1.1) mm and (9.7±1.7) mm, (16±0.9) mm and (16±1.5) mm, respectively. The diameter of the two branches of the posterior carunculae major artery was (0.62±0.02) mm and (0.98±0.06) mm. The distance from the vascular origin of the two branches to Vater’s ampulla, the inner margin of duodenum and carunculae major were (11±0.7) mm and (16.4±0.4) mm ,(13±0.3) mm and (17.9±0.3) mm, (16±0.7) mm and (19.2±0.6) mm, respectively. (2) The first branch of the anterior carunculae major arteries was at the direction 10~11 o'clock and the second branch was at the position 2~3 o'clock. The first branch of the posterior carunculae major arteries was at the position of 8~9 o'clock and the second branch was at the position of 4~5 o'clock. The branches of carunculae major arteries were primarily located at the position of 8~11 o'clock and secondarily at the position of 2~5 o'clock, and least at 11~1 as well as 6~7 o'clock.   Conclusion    In EST the incision should be made at the direction of 11~1 or 6~7 o'clock.