Application Of The Individualized Three-dimensional Printing Models In Assisting Nephron Sparing Surgery

As medical technology advances, the detection rate of small renal cancer increases year by year, and asymptomatic renal cancer is increasing. The nephron sparing surgery gradually becomes the preferred method for the treatment of exogenous type of small renal carcinoma. The key of nephron sparing surgery is the objective and accurate understanding of the tumor size, location and relationship around preoperatively. Preoperative tumor location and spatial relations in as much detail as possible can help the best operation scheme formulated and more effective doctor-patient communication, reduce the operation risk, and improve the successful rate of surgery. Based on this, we put the CT image data through the specialized processing software to edit and connect the three-dimensional printer to rebuild the kidney and tumor physical model, providing an effective means of auxiliary for clinical surgery.Objectives:To investigate the application value of individualized Three-dimensional printing in nephron sparing surgery for renal cell carcinoma.Methods:(1) To obtain the source to print:During January to July 2015,6 cases of renal cell carcinoma patients were treated with NSS in our department. Patients experienced urinary tract CT scans preoperatively and the images were saved as a dicom format.(2) Data processing:We imported the data into Mimics three-dimensional modeling software, reconstructing three-dimensional anatomical model, and exporting three-dimensional model of the kidney, tumor, vascular and collecting system. Finally, we can get a STL format file can be recognized by three-dimensional printers.(3) Reconstruction of three-dimensional printing model:We used a three-dimensional printer to rebuild the high fidelity of proportion of individualized kidney and tumor model, while the tumor and normal renal parenchyma were presented with different colors of ABS resin print respectively. Renal blood vessels and collecting system can also be printed out at the same time.(4) Effect verification of preoperative communication with reconstruction model:The surgeon respectively used the three-dimensional printing models, communicating with the patients. In addition, as a control group,6 patients undergo nephron sparing surgery, were randomly selected, using traditional CT image to communicated.All patients answered the related questions. The communication effect was scored and analyzed statistically.Results:(1)6 cases of tumor patient’s kidney models were reconstructed preoperatively and referenced carefully, assessing the relationship of the tumor, kidney and blood supply accurately.(2) The degree of cognition, including renal function, renal tumor characteristics, operation process and possible complications, was improved significantly, after using the reconstruction model to communicate.(3) All the patients were performed laparoscopic nephron sparing surgery successfully, with three-dimensional printing model intraoperative reference. The average block ischemia time was 27.2 min, an average of 116.7 ml blood loss, and no complications, postoperative pathology of renal clear cell carcinoma in all 6 cases, all with negative margin.Conclusions:We can reconstruct the kidney and tumor models before NSS through three-dimensional printing technology, which can effectively help the surgeon in the preoperative more intuitive and accurate understanding of the tumor location relationship with the surrounding tissue, so as to make the best surgery operation scheme and make an accurate assessment of operation difficulty and risk. In addition, it can improve the patients and relatives to the understanding of disease recognition.