Temperature and Pressure Measuring Endoscope

Clinical studies have shown that when the intrarenal pelvic pressure remains above 30 mmHg, obstruction of venous and lymphatic drainage in the renal pelvis occurs. This allows bacteria and toxins to enter the bloodstream, significantly increasing the risks of urosepsis, hydronephrosis, and renal parenchymal hemorrhage. In addition, if the intracavitary temperature exceeds 43°C for more than 3 seconds, thermal injury to the urinary tract mucosa will occur, leading to postoperative mucosal edema, stricture, persistent hematuria and other complications.

The new integrated temperature and pressure measuring ureteropyeloscope builds upon the conventional flexible/rigid endoscope or access sheath structure. It integrates miniature pressure sensors, high-precision temperature sensors and data transmission modules, paired with an intelligent monitoring and control platform. The system enables real-time acquisition, dynamic display, over-limit early warning and automatic regulation of pressure and temperature during surgery. The overall system features high precision, low latency, miniaturization and strong compatibility. It is compatible with standard flexible and rigid ureteroscopes as well as various laser lithotripsy devices.

Fiber-optic temperature-pressure sensors and miniature piezoresistive pressure sensors are widely used at present. The cost of sensors for disposable endoscopes/access sheaths ranges from 60 to 120 US.

Some sensors cost only 1 US, excluding those made merely for marketing gimmicks without actual temperature and pressure measurement functions.

Equipped with a built-in ultra-miniature pressure sensing chip that directly contacts the luminal surface of the renal pelvis and ureter, the device dynamically collects intrapelvic pressure data at a frequency of 6 times per second or higher. Data is transmitted in real time to an intelligent display screen to accurately present the fluctuation curve of intracavitary pressure. The clinically accepted safety parameter system defines the safe fluctuation range of renal pelvic pressure as -15 to 5 mmHg, with 20 mmHg as the warning threshold and 30 mmHg as the safety limit threshold. During surgery, if excessive perfusion flow or luminal blockage causes pressure to approach or exceed the limit, the system immediately triggers audible and visual alarms. Meanwhile, it automatically links with perfusion and negative pressure suction equipment to dynamically adjust perfusion flow rate and negative pressure, stabilizing renal pelvic pressure within the safe range and preventing pressure buildup.

Compared with the indirect monitoring method using traditional external pressure catheters, the built-in sensor structure requires no additional surgical instruments and does not occupy the working channel. It delivers more accurate measurements and faster response, effectively avoiding drawbacks of conventional monitoring such as cumbersome operation, data lag and large measurement errors.

A high-precision thermal sensing element is integrated at the tip of the endoscope to capture real-time temperature changes of intracavitary fluid and tissues during laser lithotripsy and mucosal thermal injury. The temperature measurement accuracy reaches ±0.1°C, and the temperature monitoring range covers all clinical surgical scenarios. In accordance with clinical safety standards, the system sets 43°C as the temperature safety threshold. When concentrated heat generation during laser lithotripsy or abnormal rise of perfusion fluid pushes intracavitary temperature beyond the limit, the system issues a rapid alarm. It then automatically pauses laser output and increases the circulation rate of low-temperature perfusate to accelerate heat dissipation inside the cavity, preventing sustained local high-temperature injury to the urinary tract mucosa and renal parenchyma.

The sensing module features a tiny footprint and does not compromise the flexible deflection of the endoscope or lithotripsy and stone retrieval operations. It is compatible with mainstream lithotripsy equipment including super-pulsed thulium lasers and holmium lasers.

The complete device establishes an integrated intelligent system of "monitoring – warning – regulation – recording". It continuously stores dynamic intraoperative pressure and temperature data and generates surgical parameter reports, providing objective data support for postoperative condition assessment, complication tracing and surgical protocol optimization. In addition, the system adapts to different surgical positions, varying perfusion flow rates and complex stone surgery scenarios. It automatically adjusts parameter control logic while balancing clear surgical vision and operational safety.

Most patients with upper urinary tract stones have concomitant occult urinary tract infections. During conventional surgery, high renal pelvic pressure damages the mucosal barrier of the urinary tract, allowing bacteria and endotoxins to enter the bloodstream. This is the primary trigger for postoperative urosepsis, which can be life-threatening in severe cases. The intelligent pressure monitoring system controls renal pelvic pressure throughout the procedure to prevent pressure buildup and reduce routes for toxins and bacteria to invade blood circulation. Meanwhile, real-time pressure data guides surgeons to standardize operations and avoid forceful perfusion and prolonged high-pressure distension, fundamentally lowering the risk of infection spread. Multiple controlled clinical studies have confirmed that patients undergoing surgery with the intelligent pressure and temperature-controlled ureteropyeloscope show a marked reduction in the incidence of postoperative fever, urinary tract infection and sepsis compared with conventional surgery.

During laser lithotripsy, concentrated local energy causes an instantaneous rise in intracavitary temperature. Conventional surgery cannot detect temperature changes in real time, which may easily lead to thermal burns of the ureteral and renal pelvic mucosa. After mucosal healing, scar adhesions form, resulting in long-term complications such as upper urinary tract stricture and hydronephrosis. The real-time temperature measurement function precisely monitors the intracavitary thermal environment and intervenes promptly when high temperatures occur to halt thermal injury progression. It maximally preserves the integrity of urinary tract mucosa, effectively reducing the incidence of postoperative ureteral stricture, persistent hematuria, dull lumbar pain and other complications, and improving patients’ long-term prognosis.

To avoid high-pressure risks in conventional operations, perfusion and lithotripsy often need to be intermittently suspended, disrupting surgical continuity and prolonging operative time. The intelligent temperature and pressure monitoring system enables continuous and stable perfusion while maintaining safe pressure and temperature levels, ensuring a clear surgical field and supporting uninterrupted lithotripsy and stone retrieval. It greatly improves stone clearance efficiency and shortens surgery duration. For complex cases such as staghorn calculi and multiple fine fragmented stones, the system’s dynamic parameter regulation capability adapts to complex surgical scenarios and raises the one-time stone clearance rate for complex stones while ensuring safety.

Intraoperatively recorded data including pressure, temperature, perfusion flow rate and laser working duration enables quantitative traceability of surgical maneuvers. It breaks the limitation of conventional surgery that relies heavily on surgeons’ experience, provides objective data for standardized clinical surgical training, review of difficult cases and optimization of treatment protocols, and also supplies data support for evidence-based medical research on minimally invasive diagnosis and treatment of the upper urinary tract.