V-71 Presentación: Vídeo

Flexible Ureterorenoscopy and Hybrid Thulium Laser Lithotripsy with ClearPetra® Ureteral Access Sheath
João Vital; Mariana Madanelo; Sofia Mesquita; Avelino Fraga; Vítor Cavadas
Centro Hospitalar Universitário de Santo António


The ClearPetra System combines the utility of an access sheath for laser lithotripsy, with continuous flow fluid dynamics. This system uses the vortex created by continuous high-flow irrigation and vacuum fluid dynamics to attract and capture fragments while reducing overall urinary tract pressure.

We aim to share our experience using the ClearPetra® Suction Ureteral Access Sheath to completely remove an impacted ureteral stone.


A 50-year-old female was referred to urology in may 2023 due to a renal colic she maintained for 6 months. She had past surgical history of parathyroidectomy due to hyperparathyroidism and semi-rigid ureteroscopy and laser lithotripsy for a ureteral stone. 

The ultrasound revealed right hydronephrosis caused by a 14mm stone in the proximal ureter and the KUB x-ray showed a stone with 16x7mm in the right lumbar ureter.

Extracorporeal Shock Wave Lithotripsy was performed but the stone remained stable after the procedure. 

She undergone a Flexible Ureterorenoscopy and Hybrid Thulium Laser Lithotripsy with ClearPetra® Ureteral Access Sheath with Double J Stenting in November 2023.

Under general anesthesia patient was positioned in lithotomy position. A guide wire was placed and the x-ray confirmed the position of the stone. Progression to the renal pelvis was not possible due to impaction of the stone in the proximal ureter.

The Clear Petra Ureteral Access Sheath was introduced and hybrid Thulium Laser Lithotripsy was performed.

The tip of the ureteral access sheath was used to help mobilizing some impacted stone fragments.

The fragments were evacuated progressively. A stone basket was also used for some impacted fragments. The final pyelogram showed absence of extravasation of contrast.

The surgery had a duration of 90 minutes. The laser time was around 20 minutes. The pressures used for suction and irrigation through the ureteral sheath were both 150 mmHg.


Postoperative course was uneventful. The double J stent was removed 2 weeks after surgery. 3 months after surgery, the patient is asymptomatic and the abdominal and pelvic CT confirmed the stone-free status.

The infrared spectroscopy revealed a stone composed of 50% calcium oxalate dihydrate; 20% calcium oxalate monohydrate and 30% apatitis.


This case highlighted several benefits of employing the ClearPetra® Ureteral Access Sheath. This approach facilitated the execution of the procedure with diminished intraluminal pressure, thereby decreasing the likelihood of calyceal injury, infection, and sepsis. Likewise, the removal of dust and smaller stone fragments enhanced our field of vision and minimized the risk of inflicting damage to the ureter. Also, the soft bendable tip of the sheath helped on the removal of some impacted fragments without causing damage to the ureter.