Surgical technique
Written informed consent was obtained from all the patients. A
retrograde pyelography was performed in all patients to control the
entire renal collecting system. A 0.035-inch safety guidewire was
placed.
In group 1 (sURS group), a second hydrophilic guidewire was carried out
into the ureteral orifice through the sURS’s (8f or 9f Fr, Karl Storz,
Rietheim-Weilheim, Germany) working channel. A semirigid ureteroscope
was gently passaged between these two guidewires (“railroad”
technique) [10]. The optical ureteral dilatation was done with sURS,
and the entire ureter was assessed for anatomy, additional pathologies,
and calibration of the ureter. Then, a UAS of an appropriate diameter
was placed just below the ureteropelvic junction for renal stones and
just below the stone for upper ureteral stones under fluoroscopic
guidance.
In group 2 (non-sURS group), the UAS was inserted directly by gliding
over the working guidewire. First, a 10-12 f or a 11-13 f UAS was tried.
If these sizes were unable to pass to the collecting system, or there
was stenosis in the ureter during sURS (for group 1), a smaller UAS was
tried under fluoroscopic control. If all attempts failed, insertion of a
bare flexible URS (fURS) was tried over guidewire. If this attempt was
unsuccessful, the procedure was stopped and a JJ stent was placed and
the patient was scheduled for reoperation after three or four weeks.
After the UAS was placed, renal stones were fragmented by a holmium:YAG
laser. Laser energy and pulse frequency were varied based on stone
burden and density. If possible, lower pole stones were repositioned
into the upper or middle calyx. Stone fragments over 2-3 mm were
extracted by a nitinol basket catheter. A JJ stent was usually left in
place according to surgeon preference.
During follow-up, the urinary ultrasound and KUB radiography were done
in the follow-up visit after the first month. NCCT was performed in
suspicious and necessary cases. Stone-free status was defined as no
residual fragments or the presence of residual fragments up to 3 mm.
Surgical success was defined as patients’ achievement of stone-free
status after a single lithotripsy session without the need for
additional sessions or ancillary procedures.