This is a phase I feasibility study to investigate the use of a novel intelligent robotic retrograde intrarenal surgery (RIRS) platform. The TaloStone T1000 RIRS system can manipulate the flexible ureteroscope, with remote control of the instruments (laser fibre or basket) and ureteral access sheath movements. Beyond teleoperation, the TaloStone T1000 RIRS system integrates AI perception models and decision-making algorithms to enable the supervised autonomous execution of critical tasks within the RIRS workflow.

I. Introduction

Retrograde intrarenal surgery (RIRS) has become a preferred method for the diagnosis and treatment of urological diseases, such as kidney stone removal. However, the complex urinary and limited visibility of existing endoscope lead to inefficient manipulation of flexible ureteroscopes. Besides, conventional flexible ureteroscopy requires repetitive manual manipulation, which often results in surgeon fatigue, mucosa injury from respiratory motion, and variable stone clearance rates, particularly in complex calyceal anatomies.

The research focuses on the development of an novel robotic system for RIRS, currently dubbed "TaloStone T1000". The robotic system platform consists of a surgeon control console, a multi-functional video cart, and patient-side robotic arm with fiber-optic-sensitized flexible ureteroscopy as shown in Fig. 1. The surgeon console with optimized design of ergonomics is equipped with haptic master devices for smooth and precise control of the robotic arm to manipulate the flexible ureteroscope as well as instruments, e.g., stone baskets and laser fibers. The system also supports seamless integration of multiple modalities, including pre-operative CT scans, intra-operative endoscopic videos, and fiber-optic sensing. Besides, the self-developed flexible ureteroscope is embedded with fiber optic sensors for real-time shape sensing, force estimation, and simultaneous intrarenal pressure control and temperature monitoring. Shape sensing enables precise navigation of the ureteroscope within the renal collecting system, and force estimation provides accurate feedback of tip contact interaction to the master devices on the surgeon control.

Moreover, AI algorithms are incorporated to assist in diagnostics and higher level of supervised surgical autonomy, thereby improving safety and efficiency. The investigators developed AI-powered diagnostics for stone sensing, laser fiber recognition, depth awareness, and CT-to-endoscopy localization. Based on the sensing results from AI-powered diagnostics, the investigators proposed a supervised framework that can automate repetitive procedures throughout in-sheath and ureter navigation, laser approaching, and laser trajectory planning. The entire operation is under supervision of the surgeon, who can use one trigger on the master device or footswitch to enable or disable the supervised automated features. The foot pedal of laser device remains to trigger laser emission by the surgeon for stone fragmentation, dusting, and pop-corning. The basic safety and essential performance of both hardware and software in the robotic system were developed under clinical standards and medical device regulations.

To date, a total of three cadaveric studies have been conducted using the robotic system. In August 2024, the investigators performed the first cadaver study of the robotic system at Prince of Wales Hospital (PWH), where user study of ergonomic manners and tele-operation control of stone treatment was investigated. The second and third cadaver studies, focusing on the AI-powered features of the robotic system, were completed at PWH in June and December 2025. Synthetic renal stones of around 3mm were retrogradely inserted to the renal collecting systems, with successful fragmentation via the robotic RIRS system using Holmium:YAG laser. Over 10 doctors from PWH and the Chinese University of Hong Kong, participated in the cadaver studies. The current system response, motion speed of the robotic system, and operations with ergonomic control console can satisfy the requirements of the doctors. In addition to the cadaver studies, the investigators have conducted a set of laboratory testing and experiments, validating its robustness and stability of the system.

Subsequent to successful cadaveric experiments, the investigators planned to further validate of the feasibility of the use of the system in clinical cases. In this study, the investigators aim to evaluate the robotic system's safety and feasibility in RIRS in a stage 1, proof of concept study that follows the concepts outlined in the IDEAL framework (Idea, Development, Exploration, Assessment, Long-term Study).

II. Methods

Aim

The aim of this study is to evaluate the feasibility and safety of performing RIRS using the TaloStone T1000 system.

Study Design

This is a prospective, single-arm study that will be conducted by investigators from The Chinese University of Hong Kong/Prince of Wales Hospital in the period from November 2025 to June 2026. The investigators are experts in endo-urological surgery and robot-assisted surgery. The study design follows the guidelines for stage 1 of the IDEAL framework. The study will be carried out in accordance with the Declaration of Helsinki of the World Medical Association and the International Conference on Harmonization - Good Clinical Practice.

The study information will be provided to subjects during a preoperative consultation by the investigators and the research staff. Subjects will be provided with approved informed consent explaining the study procedure, risks, assessments, and required compliance; and will be given ample time to make their decision regarding participation in the study.

Perioperative data and outcomes from all cases of those participating in the study will be reviewed by an independent Data and Safety Monitoring Committee (consisting two senior urologists not involved in this study) for safety and identification of serious perioperative complications (within 30 days after the surgery) as interim to safeguard study subjects. The Committee will make periodic recommendations to the study team on whether to continue, modify, or prematurely terminate the study. Any adverse events will also be immediately reported to the Clinical Research Ethics Committee of the hospital.

Reporting of this stage 1 study will follow the IDEAL Reporting Guidelines.

Inclusion criteria

1. Adult patients >18 years old
2. Renal stone(s) less than 1cm 2cm in maximal length
3. Clinically indicated for RIRS
4. Willingness to participate as demonstrated by giving informed consent

Exclusion criteria

1. Patients with no preoperative CT imaging available
2. Patients who are not recommended to receive RIRS
3. Severe concomitant illness that drastically shortens life expectancy or increases risk of therapeutic intervention
4. Untreated active infection
5. Un-corrected coagulopathy
6. Presence of another malignancy or distant metastasis
7. Emergency surgery
8. Vulnerable population (e.g. mentally disabled, pregnant)

Study protocol, statistical analysis plan, informed consent form, clinical study report, analytic code will be available.

It will be available after the publication of the manuscript (latest 31 Dec 2027 by estimation), and will be available for up to 5 years afterwards

IPD will be shared in a de-identified manner for reasonable studies with approved from the relevant institutional review board.