Role of virtual reality in improving the spatial perception of the kidney during flexible ureteroscopy: A feasibility study using virtual reality simulators and 3D models.

Background: The aims were to describe a software-based reconstruction of the patient-specific kidney cavity intraluminal appearance via a head-mounted device and to estimate its feasibility for training novices. Materials and methods: In total, 15 novices were recruited. Each novice was shown a three-dimensional reconstruction of a patient's computed tomography scan, whose kidney was printed. They then joined the surgeon in the operating room and assisted them in detecting the stone during flexible ureteroscopy on the printed model. Then, each participant did a 7-day virtual reality (VR) study followed by virtual navigation of the printed kidney model and came to the operating room to help the surgeon with ureteroscope navigation. The length of the procedure and the number of attempts to find the targeted calyx were compared. Results: With VR training, the length of the procedure (p = 0.0001) and the number of small calyces that were incorrectly identified as containing stones were significantly reduced (p = 0.0001). All the novices become highly motivated to improve their endourological skills further. Participants noticed minimal values for nausea and for disorientation. However, oculomotor-related side effects were defined as significant. Five specialists noticed a good similarity between the VR kidney cavity representation and the real picture, strengthening the potential for the novice's education via VR training. Conclusions: Virtual reality simulation allowed for improved spatial orientation within the kidney cavity by the novices and could be a valuable option for future endourological training and curricula.

Miniaturization of flexible ureteroscopes: a comparative trend analysis of 59 flexible ureteroscopes.

The purpose of this review is to analyze the trend in miniaturization of flexible ureteroscopes over the past decades, identify the advantages and disadvantages, and determine the correlation of individual parameters with release period. Flexible ureteroscopes mentioned in the literature or those commercially available were searched. To minimize the search bias, the instruments were grouped by release date time periods of < 2000 year, 2000-2009, 2010-2019, and 2020 onwards. The final review included only those instrument models for which data on tip size, overall shaft, working length and channel size had been determined. The correlation among features investigated as well as with release period was also determined. 59 models of flexible ureteroscopes (26 fiber optic and 33 digital scopes) were included. Among the different features investigated among fiber optic endoscopes, only the sizes of the distal tip and overall shaft positively correlated with each other. In contrast to their fiber optic counterparts, a strong positive correlation was observed between tip and channel sizes, whereas negative correlation was found between channel size and overall shaft size and working length of digital scopes. Only distal tip of fiber optic flexible ureteroscopes and overall shaft of digital endoscopes were significantly reduced over their evolution. With the development of technology, there has been an improvement of flexible ureteroscopes and one of the indicators of this trend is a decrease in their size. With a definite trend towards miniaturization over the past decades, a significant correlation was observed in tip size and overall shaft for fiber optic and digital endoscopes, respectively.

Expanding horizons and navigating challenges for enhanced clinical workflows: ChatGPT in urology.

Purpose of review: ChatGPT has emerged as a potential tool for facilitating doctors' workflows. However, when it comes to applying these findings within a urological context, there have not been many studies. Thus, our objective was rooted in analyzing the pros and cons of ChatGPT use and how it can be exploited and used by urologists. Recent findings: ChatGPT can facilitate clinical documentation and note-taking, patient communication and support, medical education, and research. In urology, it was proven that ChatGPT has the potential as a virtual healthcare aide for benign prostatic hyperplasia, an educational and prevention tool on prostate cancer, educational support for urological residents, and as an assistant in writing urological papers and academic work. However, several concerns about its exploitation are presented, such as lack of web crawling, risk of accidental plagiarism, and concerns about patients-data privacy. Summary: The existing limitations mediate the need for further improvement of ChatGPT, such as ensuring the privacy of patient data and expanding the learning dataset to include medical databases, and developing guidance on its appropriate use. Urologists can also help by conducting studies to determine the effectiveness of ChatGPT in urology in clinical scenarios and nosologies other than those previously listed.

Impact of High-fidelity Nonbiological Kidney Puncture Trainer on Residents' Skills During 30-Day Practical Course.

OBJECTIVE: To describe the manufacture of the nonbiological kidney cavity puncture trainer under ultrasound control and its benefits during the 30-day learning course of junior residents. METHODS: Ten junior residents were included in this work. Each participant performed a kidney puncture on the described simulator under ultrasound control every day for a 30-day practical course. Also, ten urologists were included in the work and performed punctures on the trainer; the results obtained were compared with the residents' results on the 1st and 30th days of the study. The Face, content, construct, and criterion validities of the simulator have been defined. The residents also assessed the change in tactile sensations after the simulator's integrity restore and the increase in their motivation for a more in-depth study of all aspects of kidney puncture. RESULTS: All residents could independently perform a kidney puncture on the simulator through the calyx papilla, which was statistically significant compared with the results on day 1 of training. When comparing the final results of the residents with the urologists' ones, there were similar. Face, content, and construct validity were 4/5, 5/5, and 4.5/5. There was no change in tactile sensations during the everyday restoration of the simulator's integrity. All residents noted the positive effect of the described simulator on their motivation in mastering percutaneous kidney puncture. CONCLUSION: The described simulator allows young residents to gain experience performing punctures of the kidney cavity, which positively affects their motivation to improve obtained skills further.

Three-Dimensional Reconstruction of Pelvicalyceal System of the Kidney Based on Native CT Images Are 1-Step Away from the Use of Contrast Agent.

OBJECTIVE: To describe special algorithm for the semi-autonomous 3-dimensional reconstruction of the pelvicalyceal system based on native computed tomography images of patients with upper urinary tract obstruction. MATERIALS AND METHODS: Fifty patients with renal colic fitting to inclusion criteria were enrolled. All patients underwent computed tomography urography to perform 3-dimensional reconstruction of the pelvicalyceal system on the affected size based on excretory phase representing "gold standard" and on native phase, which was performed via Medical Imaging Interaction Toolkit program updated with the described algorithm. Five urologists estimated their similarities and the potential use of non-contrast models for interventional planning. Contralateral non-distended pelvicalyceal system was reconstructed to evaluate the viability of the proposed technology in such cases. Surface areas of contrast and non-contrast models were compared. Distended pelvicalyceal system of 1 patient was used to reconstruct virtual endoscopic view. Obtained 3-dimensional noncontrast pelvicalyceal system models were analyzed by an engineer for suitability for 3-dimensional printing. RESULTS: The average surface area of contrast and non-contrast models was 3513 and 3371 mm2 , respectively (P=.0818). Non-contrast 3-dimensional reconstruction was possible with all distended pelvicalyceal systems and with 9 non-distended cases. Properties of non-contrast models were estimated as 4.3 out of 5. Obtained models were suitable for their intraluminal reconstruction and potential 3-dimensional printing. CONCLUSION: Described semi-autonomous approach allows for 3-dimensional reconstruction of dilated pelvicalyceal system based on non-contrast computed tomography images.

InsKid-a new mobile application (app) that measures the infundibulopelvic angle before retrograde intrarenal surgery more reliably than does other approaches: pilot study.

OBJECTIVE: This study compared our program's ("InsKid") capability for measuring the infundibulopelvic angle (IPA) with existing ones. METHODS: Prospectively, data from 50 patients with lower pole kidney stones with indications for retrograde intrarenal surgery (RIRS) were collected. All patients underwent computed tomography (CT)-urography. The IPA of each pelvicalyceal (PCS) unit was measured with the Elbahnasy's, Sampaio's, and "InsKid" methods. Results were compared. Finally, we compared the area under the receiver operating characteristic (ROC) curve (AUC) for predicting stone-free status after RIRS. We defined success as stone fragments ≤ 2 mm on the CT scan on the first postoperative day (POD1). The stone-free rate refers to no identifiable stone fragments on the POD1 CT. Test-retest reliability and face validity were defined to estimate psychometric properties of InsKid. RESULTS: The success rate after first procedure was 87.5%. The average value of IPA using the Elbahnasy and Sampaio methods and our program were 85.2° ± 11.9°, 95.1° ± 10.1°, and 79.9° ± 13.0, respectively. There was a significant difference among the InsKid, Elbahnasy, and Sampaio (AUC = 0.762, 0.601, and 0.629, respectively) approaches with respect to the capability of predicting the immediate success of RIRS. Repeated measurement did not affect values of IPA (1.3° ± 0.7, p = 0.67). All specialist appreciated proposed software as highly useful (5/5). CONCLUSION: This new application reproduces the intraoperative aspects of the PCS more clearly than the other methods and also provides an easy solution for clearly defining the IPA without relying on the central axes.

Ureteral substitution with appendix.

OBJECTIVE: To study the long-term results of ureteral reconstruction with the appendix in patients with long ureteral strictures. METHODS: From 1998 to 2019, 26 patients were operated with substitution of extended defects of the ureter with the appendix. There were 22 women and four men (mean age 44.7 ± 11.3 years). One patient had stricture of the lumbar ureter because of a gunshot wound. He underwent substitution of the upper third of the right ureter with the appendix. In the other cases, we carried out substitution of the pelvis part of the ureter with appendix, in four cases from the left side. In the last 22 cases, a novel surgical technique for better appendicovesical anastomosis was carried out: a flap was dissected from the dome of the cecum to increase the diameter of anastomosis. RESULTS: The postoperative follow-up period was from 1 to 21 years. A stricture of uretero-appendical anastomosis developed in four patients (15.4%). Resection of stricture and re-anastomosis was carried out in one case. In another two cases associated with similar complications, endoureterotomy and ureteral stenting were carried out. One patient was managed with percutaneous nephrostomy. Kidney function was restored in all patients. Good short-term results were achieved in 22 patients (84.6%) and long-term (from 1 to 21 years) results in 25 patients (96.2%). CONCLUSIONS: In patients with long ureteral stricture, the use of the appendix can help to restore the function of the upper urinary tract.

The use of the three-dimensional printed segmented collapsible model of the pelvicalyceal system to improve residents' learning curve.

OBJECTIVE: The aim of the present study was to determine the effectiveness of the use of the three-dimensional (3D) printed segmented collapsible model of the pelvicalyceal system (PCS) to improve the learning curve of the residents. MATERIAL AND METHODS: 3D printed models based on computed tomography (CT) images of 10 patients with a staghorn stone were developed. Used images of patients were obtained from CT scans in Digital Imaging and Communications in Medicine format. The area of interest was extracted and saved in stereolithography format. Further, the bioengineer performed virtual segmentation corresponding to the level of each calyces group that was defined by an experienced urologist. The final stage was the printing of each separated detail. Special questionnaire for evaluating the effectiveness of 3D models during both the examination of PCS anatomy and planning percutaneous nephrolithotomy was invented. RESULTS: The determination of the anterior and posterior calyces of the upper group was improved by 61% and 69%, the difference in the determination of the calyces of the middle group was 60% and 51%, and the answers regarding the number of the anterior and posterior calyces of the lower group became better by 67% and 74%, respectively (p<0.001). The ability to select the optimal calyx for the primary and the second access became better by 60% and 55%, respectively (p<0.001). CONCLUSION: 3D printed segmented collapsible model of the PCS is promising for the improvement of the learning curve of residents and enables to optimize their clinical education, as well as compensate for their lack of experience.