Nonpapillary prone endoscopic combined intrarenal surgery accomplishes better "stone-free-rate" and fewer complications

Greece: Nonpapillary prone Endoscopic Combined Intrarenal Surgery (ECIRS) has proven safety and effectiveness with good stone-free-rate and outcomes, benefitting mostly patients with renal abnormalities, incrusted ureteral stents, and staghorn stones, as per the latest study published in the World Journal of Urology.

Over the years, many technical aspects have been discussed and shared to improve treatment outcomes. ECIRS combines PCNL with retrograde flexible ureterorenoscopy (fURS), with the primary objective of achieving higher stone-free rates (SFR) after a single procedure. The literature mentions the method has an SFR of 81.9 %, which has reportedly increased to 90 % (Scoffone et al.), while other studies say 61 to 97 % SFR with a complication rate between 61 and 97 %.

The technical aspects of the discussion have been Galdakao-modified supine Valdivia (GMSV) vs. prone split-leg position. GMSV is crucial for proper coordination, while successful studies demonstrate prone-split leg position feasibility for ECIRS.

There needs to be more data for ECIR affirmation as a reproducible technique. Considering this, a study was conducted by a team of researchers led by Panagiotis Kallidonis from the Department of Urology at the University of Patras Medical School to evaluate the nonpapillary prone ECIRS concerning safety and effectiveness. The research paper also shared tips and tricks to accomplish treatment goals considering anatomical peculiarities.

The conclusive study points are:

• The data was collected from January 2019 -December 2021 in a high-volume tertiary center.
• The study included 33 patients treated with prone nonpapillary ECIRS.
• The median age and body mass index was 54 (years) and 25.6, respectively.
• Twenty-nine patients were prestented, and 4 received alfa-blockers.
• The procedure was performed in a prone split leg position under general anesthesia by two surgeons with expertise in PCNL and RIRS.
• The stones were assessed by imaging study. The infection control was achieved with a single IV dose of either fluoroquinolone or an aminoglycoside.
• Most stones were treated with only one puncture.
• The requirement of two and three accesses in 15.2% and 6.1% were recorded, respectively.
• The most common PCNL tract size was 22 Fr, 64.3% of cases.
• The access sheaths used were 22Fr or 30Fr.
• Kidney stones fragmentation was done with Lithoclast Trilogy®
• Retrograde lithotripsy was performed with a holmium laser Cyber Ho 150® or MOSES (Pulse 120H) device.
• The energy settings were between 1 and 2 J, with a frequency range of 30 to 60 Hz.
• Nitinol baskets relocated and presented fragments for removal via antegrade percutaneous access.
• A double J stent (6–8Fr) and either malecot tale tubes or a balloon nephrostomy tube were placed.
• The nephrostomy or malecot tube was removed postoperatively after 2 to 3 days.
• The Double-J stent removal was done between 2 and 4 weeks after the procedure.
• The beginning of the puncture till the nephrostomy placement marked the operative time.
• The initial and final SFR was 84.8% and 90.9%, respectively.
• The median size of the stone was 35 mm.
• Nearly 60% of patients had staghorn calculi (partial or complete).
• The prevalence of renal abnormalities was 21.3%.
• A total of 7 patients had renal abnormalities. There were 3 cases of horseshoe kidney, 2 of malrotation, and 2 of complete duplicated pelvicaliceal systems.
• The median operative time was presented as 47 min.
• The median hospital stay was of 3 days.
• The median loss of hemoglobin was 1.2 gr/dL.
• The rate of complication was 9.1%
• (Grade II complications).
• Two patients had a postoperative transient fever, while one experienced bleeding (resolved conservatively).

The tips and tricks shared in the research paper include:

• Preferable split-leg position.
• The medial nonpapillary puncture enhances maneuverability and accessibility while reducing parenchyma disruption
• A guidewire "through and through" safely achieved with retrograde fURS
• A 22Fr access sheath is an appropriate diameter for large stones.
• To main a low-pressure system and reduce complications, the difference between the access sheath and nephroscope should be 4Fr.
• UAS is favorable for retrograde access.
• The "self-popping" technique is more proper than dusting.
• The activation of the lithotripter from the percutaneous tract should be avoided during RIRS.
• When the access sheath "catches" a stone, faster stone evacuation could be achieved by closing antegrade and opening retrograde irrigation.
• GMSV positioning favor easier stone extraction.
• fURS prevent stone migration to the ureter.

Dr. Arman Tsaturyan from the Department of Urology at the University of Patras Medical School wrote, " We believe that the standardization of the procedures led to the positive results of our study. Our antegrade access to the ECIRS procedure follows the same rules and steps as PCNL track establishment. We also mentioned some tips and tricks as reasons behind improved outcomes."

They added, " The limitations of our study are patient number, overcorrection of surgical steps by experienced surgeons, non-analyzed stone composition, probability of missing stones, etc."

The researchers concluded that Nonpapillary prone ECIRS is a safe and effective procedure with 90.9 % of SFR and low-grade complications. The patients who mostly benefited were those with renal abnormalities, incrusted ureteral stents, and staghorn stones.

Standardization of procedures is critical to achieving successful outcomes.

Further reading:

Kallidonis, P., Tsaturyan, A., Faria-Costa, G. et al. Nonpapillary prone endoscopic combined intrarenal surgery: effectiveness, safety and tips, and tricks. World J Urol (2022).