Robot-assisted partial nephrectomy of initial cases using a 3D square-block type kidney model

A new training model using the self-healing properties of supramolecular hydrogels for endoscopic combined intrarenal surgery

The combination of hydronephrosis formation, ureteroscopic imaging, and ultrasound delineation has not been included in any non-biological training model of percutaneous nephrolithotomy or endoscopic combined intrarenal surgery. We aimed to develop a realistic kidney phantom using the self-healing properties of supramolecular hydrogels for percutaneous nephrolithotomy and endoscopic combined intrarenal surgery and evaluate its suitability as a training model.Expert and resident urologists performed ultrasound-guided renal pelvic punctures and flexible ureteroscopies for endoscopic combined intrarenal surgery using a training model. Subsequently, the training model was evaluated using a 17-item Likert scale questionnaire (range, 1-5 points). After being filled with carrageenan, the collecting system was inflated, and the relationship between the collecting system volume and collecting system pressure was determined. The durability of the model was verified by repeatedly inserting a 16-Fr access sheath. Five novices and seven urology experts performed the procedure. The mean questionnaire score was 4.25 (standard deviation, 0.37). The model was able to hold 50 mL of air, and the pressure in the collecting system ranged from 6 to 33 mmHg. Repeated punctures were possible even when a 16-Fr access sheath was inserted. Our new training model included the self-healing properties of supramolecular hydrogels, which are tough and flexible and can be evaluated using ultrasonography. According to the questionnaire score, the model was highly satisfactory and has potential as a new educational tool.

3D printed kidney model could be an important educational tool for residents

INTRODUCTION

This study aimed to evaluate whether it is useful for junior physicians to use a three-dimensional (3D) kidney model when evaluating the R.E.N.A.L. nephrometry score.

MATERIALS AND METHODS

An expert and four urology residents retrospectively evaluated the R.E.N.A.L. nephrometry scores of 64 renal tumors (62 patients) that underwent robot-assisted partial nephrectomy at our hospital. The expert evaluated 64 R.E.N.A.L. nephrometry scores with computed tomography (CT), whereas four residents evaluated 32 cases using CT alone and the other 32 cases using CT and a 3D kidney model. The consistency between the expert and residents was assessed by Cohen's kappa score. Patient-specific 3D kidney models were created in a gird style using a 3D printer based on CT or magnetic resonance imaging of the patient.

RESULTS

For all four residents, the accuracy of the overall R.E.N.A.L. nephrometry score was significantly higher with the 3D model and CT than with CT alone (P < .001). Regarding the individual components of the R.E.N.A.L. nephrometry score, the accuracy rates of "E," "N," "A," and "L" scores were higher with the 3D model and CT than with the CT alone (P = .020-.089).

CONCLUSION

Patient-specific 3D-printed kidney models could improve the resident's understanding of the renal tumor complexity and could be an important educational tool for residents.

The use of individualized 3D-printed models on trainee and patient education, and surgical planning for robotic partial nephrectomies

3D printing is a growing tool in surgical education to visualize and teach complex procedures. Previous studies demonstrating the usefulness of 3D models as teaching tools for partial nephrectomy used highly detailed models costing between $250 and 1000. We aimed to create thorough, inexpensive 3D models to accelerate learning for trainees and increase health literacy in patients. Patient-specific, cost-effective ($30-50) 3D models of the affected urologic structures were created using pre-operative imaging of 40 patients undergoing partial nephrectomy at Thomas Jefferson University Hospital (TJUH) between July 2020 and May 2021. Patients undergoing surgery filled out a survey before and after seeing the model to assess patient understanding of their kidney, pathophysiology, surgical procedure, and risks of surgery. Three urological residents, one fellow, and six attendings filled out separate surveys to assess their surgical plan and confidence before and after seeing the model. In a third survey, they ranked how much the model helped their comprehension and confidence during surgery. Patient understanding of all four subjects significantly improved after seeing the 3D model (P < 0.001). The urology residents (P < 0.001) and fellow (P < 0.001) reported significantly increased self-confidence after interacting with the model. Attending surgeon confidence increased significantly after seeing the 3D model (P < 0.01) as well. Cost-effective 3D models are effective learning tools and assist with the evaluation of patients presenting with renal masses, and increase patient, resident, and fellow understanding in partial nephrectomies. Further research should continue to explore the utility of inexpensive models in other urologic procedures.

Novel high-quality and reality biomaterial as a kidney surgery simulation model

Surgical training using live animals such as pigs is one of the best ways of achieving skilled techniques and fostering confidence in preclinical medical students and surgeon trainees. However, due to animal welfare ethics, laboratory animals’ usage for training should be kept to a minimum. We have developed a novel kidney organ model utilizing a simple procedure in which the kidney is first refluxed with N-vinyl-2-pyrrolidone (NVP) solution for 1 hour in its bath, followed by permeation for 23 hours, with a subsequent freshwater refluxed for 48 hours in the washing step. Surgical simulation of the prepared kidney model (NVP-fixed kidney) was compared with three types of other basic known simulation models (fresh kidney, freeze-thaw kidney, and FA-fixed kidney) by various evaluations. We found the NVP-fixed kidney to mimicked fresh kidney function the most, pertaining to the hardness, and strength of the renal parenchyma. Moreover, the NVP-fixed kidney demonstrated successful blood-like fluids perfusion and electrocautery. Further, we confirmed that surgical training could be performed under conditions closer to actual clinical practice. Our findings suggest that our model does not only contribute to improving surgical skills but also inspires the utilization of otherwise, discarded inedible livestock organs as models for surgical training.

Natural history of asymptomatic renal artery pseudoaneurysm after robot-assisted partial nephrectomy

Background

We assessed the natural history of renal artery pseudoaneurysm (RAP) after robot-assisted partial nephrectomy (RAPN).

Methods

From May 2016 to September 2020, 106 patients underwent RAPN for renal tumors at our institution. Among 100 patients, excluding 6 who were ineligible for contrast-enhanced computed tomography (CE-CT), 4 underwent renal artery selective embolization (RAE), of which 2 cases were emergency RAE within 7 days after RAPN and the other 2 were prophylactic RAE 8 or more days after RAPN. In 98 patients examined for the clinical course of asymptomatic RAP managed by surveillance, excluding the 2 who underwent emergency RAE, routine CE-CT was performed at 7 days, 1 month and 3 months after RAPN. Factors influencing the occurrence of RAP among these 98 patients, including the 2 who underwent emergency RAE and excluding the 2 who underwent prophylactic RAE, were analyzed by logistic regression analysis.

Results

Median [interquartile range (IOR), range] observation period, age, radiographic tumor size, and maximum diameter of RAP were 20.8 (23.9, 3.0–57.6) months, 63 (18, 22–84) years, 23 (11, 9–48) mm, and 6.6 (5.2, 3.0–16.0) mm, respectively. CE-CT detected 28 RAPs in 23 (23.0%) of 100 patients by 7 days after RAPN and routine CE-CT detected 25 RAPs in 21 (21.4%) of 98 patients excluding 2 who underwent emergency RAE at 7 days after RAPN. RAP was diagnosed by routine CE-CT in 21 (21.4%), 1 (1.0%), and 0 (0%) patients at 7 days, 1 month, and 3 months after RAPN, respectively. In univariate analysis, age [odds ratio (OR) 0.144: 69–84 vs. 22–56 years old, P=0.0179], R.E.N.A.L [radius (tumor size as maximal diameter), exophytic/endophytic properties of tumor, nearness of tumor deepest portion to collecting system or sinus, anterior/posterior descriptor and location relative to polar line] nephrometry score (OR 1.374, P=0.0382), warm ischemic time (OR 1.085, P=0.0393), and renorrhaphy time (OR 1.055, P=0.0408) were significantly associated with the occurrence of RAP. In multivariate analysis, only age (OR 0.124, P=0.0148) was a significant factor.

Conclusions

Asymptomatic RAP up to 15 mm in diameter resolved spontaneously 3 months after RAPN. Young age (under 56 years) may be a factor in the development of RAP.

Utilization of a three-dimensional printed kidney model for favorable TRIFECTA achievement in early experience of robot-assisted partial nephrectomy

Background

This retrospective study aimed to investigate whether a three-dimensional (3D) model would improve the achievement of TRIFECTA, which was defined as the absence of perioperative complications and positive surgical margins and a warm ischemia time of <25 minutes, during robot-assisted partial nephrectomy (RAPN).

Methods

Prior to RAPN, a 3D-square type kidney model was prepared and used for all RAPN procedures in patients with T1a renal cell carcinoma (RCC) treated at a single center between March 2016 and April 2019. All RAPN procedures were performed by a single surgeon.

Results

The study included 50 patients, of whom 22, 24, and 4 had low-, intermediate-, and high-risk R.E.N.A.L Nephrometry scores, respectively. The TRIFECTA achievement rate was 86.0%, and transfusion or conversion to radical nephrectomy was not required in any of the patients. Only one Clavien-Dindo grade 3 complication was reported—a pseudoaneurysm that required embolism. The TRIFECTA achievement rate was independent of the R.E.N.A.L Nephrometry scores and the surgeon’s experience level (25 cases each of early and advanced experience).

Conclusions

The 3D model contributed to the achievement of TRIFECTA during RAPN performed by a less-experienced surgeon. These findings should be further evaluated in studies involving a larger number of cases and surgeons.