Study On Three-dimensional Reconstruction Of Human Kidney Structures Based On The UroMedix-3D System And Its Guiding Significance To Renal Surgery

BackgroundSurgical renal diseases,which are common diseases with a high incidence,can usually be cured or alleviated surgically.In view of the complexity of retroperitoneal structures,it is of crucial importance to preoperatively gain a clear understanding of the anatomic relationship between the kidney and its adjacent tissues,thus providing precise surgical guidance.Conventional medical techniques(e.g.,CT and CTA)cannot display or measure the spatial anatomic relationship between the kidney and its adjacent structures in a simple and intuitive manner,so they cannot meet the increasing requirement for surgical precision.To address this problem,three-dimensional(3D)kidney reconstruction is developed to clearly display the 3D spatial configuration and interrelationship of kidney structures,and provide a large number of objective anatomic parameters for renal surgery.Nevertheless,3D kidney reconstruction is currently faced with various deficiencies(e.g.,inefficiency,poor precision and insufficient mining from clinical applications).Hence,its practical value in renal surgery is yet to be further observed.ObjectiveA three-dimensional reconstruction system of kidney was established,which included three-dimensional reconstruction software,high-precision enhanced CT scanning and three-dimensional reconstruction of kidney.Through the deep mining and analysis of the anatomic parameters of the three-dimensional model of the kidney,the guiding significance and application mode of the three-dimensional model of the kidney for the operation were explored.MethodsⅠ.Establishment of the 3D kidney model reconstruction system1.In accordance with the requirements of 3D reconstruction for the precision of CT images,usage of contrast agent,scanning time,slice thickness and resolution were set and adjusted to develop a better scanning method,to obtain enhanced renal CT data for 3D reconstruction.2.High-quality enhanced renal CT data about 173 cases were collected from the hospital from December 2015 to October 2018,to reconstruct 3D kidney models using the Uromedix-3D system.Furthermore,the spatial anatomic parameters of various tissues were measured for the purpose of surgical guidance.Ⅱ.Application of 3D kidney models in laparoscopic surgeries for renal tumor1.Laparoscopic partial nephrectomy(LPN):Clinical data about 124 cases of LPN in the department from December 2015 to October 2018 were collected.3D kidney models were preoperatively reconstructed for 78 patients to guide the renal surgery(experimental group),while only CT images were used to guide the renal surgery for 46 patients without performing a reconstruction of 3D kidney models(control group).The profile and perioperative data of the patients were statistically analyzed.2.Laparoscopic radical nephrectomy(LRN):Clinical data about 62 cases of LRN in the department from December 2016 to October 2018 were collected.3D kidney models were preoperatively reconstructed for 31 patients to guide the renal surgery(experimental group),while only CT images were used to guide the renal surgery for 31 patients without performing a reconstruction of 3D kidney models(control group).The profile and perioperative data of the patients were statistically analyzed.Ⅲ.Exploration of other retroperitoneal diseases through 3D reconstruction3D reconstruction of kidneys and focal lesions was completed for 2 patients with renal tumor accompanied with vena cava tumor thrombus,4 patients with UPJO,4 patients with adrenal tumor,and 4 patients with retroperitoneal mass,to mine anatomic parameters for the purpose of surgical guidance.ResultsⅠ.Results of 3D reconstruction3D reconstruction was completed for 173 cases totally,presenting clear andcomplete structures,strong 3D effects,and high consistency with real kidney structures.Specifically,the 173 cases included 147 cases of renal tumor,as well as some cases of UPJO,renal stone,retroperitoneal mass,and so on.The reconstruction of renal arteries numbered 170 cases with the highest grade of reconstructed artery branches as Grade 7,including 109 cases whose renal artery branches of Grade 5 or above were reconstructed,and 37 cases whose accessory renal arteries were reconstructed.The reconstruction of renal veins numbered 164 cases with the highest grade of reconstructed vein branches as Grade 4,including 138 cases whose renal rein branches of Grade 2 or above were reconstructed.Ⅱ.Application in laparoscopic surgeries for renal tumor1.LPN:The profile and tumor characteristics of patients between the two groups were not statistically different.In terms of surgical results of the experimental group and control group,the surgical time was 124.36±42.714 vs 150.20±69.772 min(p=0.026);the renal warm ischemia time was 28.18±7.514 vs 31.61±6.695 min(p=0.012);the renal tumor resection time was 9.10±3.123 vs 10.93±2.507 min(p=0.001);the retroperitoneal drainage volume within postoperative 24h was 109.35±64.865 vs 140.54±73.024 mL(p=0.015);the drainage volume within postoperative 48h was 156.82±87.257 vs 203.04±107.132 mL(p=0.010).In the experimental group,1 patient underwent postoperative hematuria.In the control group,2 patients received intraoperative blood transfusion;3 patients suffered vascular injury;2 patients underwent postoperative hematuria;1 patient underwent postoperative renal hemorrhage.2.LRN:The profile and tumor characteristics of patients between the two groups were not statistically different.The surgical time in the experimental group was shorter than that in the control group(130.1±48.9 vs 165.4±41.2 min,p<0.05),and the rest indexes were not statistically significant.Ⅲ.Exploration of other retroperitoneal diseasesBased on the exploration of a limited number of cases of renal tumor accompanied with tumor thrombus,UPJO,and retroperitoneal mass,this study found that the results of 3D reconstruction were accurate enough to provide precise surgical guidance,thus enhancing the controllability of the surgical procedure and improving the surgical success rate.Conclusion.1.High-precision CT data combined with the highly specialized UroMedix-3D system can be used to reconstruct 3D models of kidney structures precisely and efficiently.2.3D models provide an intuitive and stereoscopic spatial visual effect,and can be adopted to deeply mine the spatial anatomic parameters of kidney structures,thus satisfying the clinical demands for "integration,visualization and datamation".3.3D models have an obvious advantage in location and separation of tissues and vessels,tumor resection,and so on in the laparoscopic surgeries for renal tumor.Specifically,they can protect renal functions effectively and improve surgical efficiency and safety.4.3D models are worthy to be further explored as they can provide precise surgical guidance for other urinary diseases.5.3D models can serve as a powerful means for medical teaching and doctor-patient communication.