Digital Anatomy Of Female Abdominopelvic Ureter And Its Adjacent Structures

BackgroundAt present,the incidence of cervical cancer has been increasing gradually,making the cervical cancer the most common gynecological malignant tumor.The radical hysterectomy is one of the main surgical treatments,in which ureteral dissociation is the main step.However,due to its invisibility in the operation and special anatomical physiology characteristic,ureter is prone to be injured in the operation compared with other organs.Once the ureter gets injured,it will be associated with oliguria,abdominal distension,abdominal pain and other symptoms.What's more,serious complications will happen in severe samples,such as hydronephrosis peritonitis,oliguria,no urine,acute renal insufficiency and so on.Therefore,in order to improve the success rate of surgery and reduce the incidence of complications,the surgeon needs to have a comprehensive grasp of the position of the ureter and adjacent structures.ObjectiveThis present research uses CTA images data set to build a three-dimensional model of the ureter and adjacent structures to avoid the ureteral injury in radical hysterectomy.Through 3D measurement to calculate the distances between ureter and abdominal pelvic blood vessels and the distance of the uterus to ureter,it aims to provide a quantitative parameter for ureter dissociation in radical hysterectomy.Methods1.Choose 10 New Zealand rabbits as the research animals,and measure the angle,diameter and length of the dorsal artery and internal and external iliac artery after anesthesia.Collect CT images,measure the angle,diameter and length of arteries in three-dimensional model reconstructed via digital technology.Compare the parameters obtained with the two measure methods and discuss the statistical significance and accuracy of the measurements.2.Collect the CT data of 65 cases of female pelvic cavity,investigate the way ureter crossing the iliac artery.Three-dimensional reconstruction was performed on the pelvic blood vessels and ureters.The horizontal distances between the ureter and the pelvic artery at different bifurcation points were measured,and the difference between left and the right side distances was statistically analyzed.3.The CT date of the 65 women was used to observe the movement of the pelvic segment of the ureter and measure the horizontal distances between the ureter and the"ureteral tunnel entrance",the lateral margin of the inner cervical mouth and the lateral margin of the outer cervical mouth.The difference between the left and the right side distance was statistically analyzed.Results1.In this study,the artery models were constructed successfully.No signi-ficant difference between the 3D reconstruction measurement method and vivo measurement methods in New Zealand rabbits was observed(P>0.05).2.There were three structural types of ureter cross the iliac artery,on the left side:the common iliac artery(33.84%),the confluence of common iliac artery(13.85%),external iliac vein(55.38%);on the right side:the common i-liac artery(27.69%),the confluence of common iliac artery(20.00%),external iliac vein(52.30%).The distance between the abdominal aorta bifurcation and ureter:left:32.45±6.24 mm,right:32.45±6.24 mm;The distance between the left bifurcation of the abdominal aorta and the left ureter was 32.45±6.24 mm and the distance of the right was 32.45±6.24 mm;the distance between the le-ft bifurcation of the common iliac artery and the left ureter was 10.5514.85 m m and the distance of the right was 13.34±5.49 mm;Statistical-ly significant d ifference of distances between the above two sides was observed for all the m easurement(P<0.05).3.The entrance of the 'ureteral tunnel' corresponds to the cervix(66.15%)and the entrance of the ureter into the bladder corresponds to the vagina(70.7%).the distance between the left ureteral tunnel entrance and the left uterine body was 16.94±6.83 mm and the distance of the right was 18.11±6.53 mm,the distance between the left ureter and the left lateral margin of the innercer-vical was 19.26±7.62 mm,and the distance of the right was 22.5±7.41 mm;the distance between the left ureter and the left lateral margin of t-he external cervical was 17.06± 6.19 mm and the distance of the right was 22.49±4.94 mm.The differences between the above two sides were statistic-ally significant.(P<0.05).Conclusion1.The 3D reconstruction technology presents high accuracy and precision in measuring the angle?diameter and length parameters.2.By measuring the three-dimensional space distance between the ureter and the artery,we discovered the shortest horizontal distance is the distance between the bifurcation of the common iliac artery and the ureter.The longest horizontal distance is the distance between the bifurcation of the abdominal aorta and the ureter.The structure of the ureter crossing the iliac artery is complex and the most of them are external iliac arteries.3.The ureter is closer to the left side than the right side in cervical and the whole cervix showed a left-leaning trend.The'tunnel entrances'correspond to the cervix.Most of the ureter corresponds to the vagina in bladder.