Retrograde Intrarenal Surgery

1. FLEXIBLE
URETERORENOSCOPY
or
RIRS
Gaurav Nahar
DNB Urology Resident
MMHRC

2. INTRODUCTION
• Trend in surgical practice today is towards
developing minimally invasive techniques.
• Endoscopic surgery using minimally
invasive techniques has been the frontier
of medical innovation in last two decades.
• Development of small calibre flexible
instruments permits endoscopic surgery of
urinary tract to treat a wide variety of
lesions/conditions within the kidney.

3. Rising trend for URS...Why???
• Shorter hospital stay
• Lower costs
• Improved cosmesis
• Earlier return to work
• Suboptimal results with ESWL(for renal
stone disease)

4. FLASHBACK...
• 1912: 1st Ureteroscopy by Hugh Hampton
Young ("Father of Modern Urology"); a
rigid 12Fr cystoscope was advanced into
massively dilated ureter of a pt. with PUV.
• Late 1950's: development of first fibreoptic
endoscope.
• 1964: first flexible ureterorenoscopy by
Marshall via a ureterotomy using a 9Fr
flexible endoscope for diagnostic
purposes.

5. • 1977: Goodman & Lyon reported first rigid
ureteroscopy for therapeutic purposes.
• 1990: Fuchs & Fuchs reported the first
large series (208 patients) of renal calculi
treated by flexible ureteroscopy.
• 1998: contemporary RIRS using flexible
ureterorenoscope and Holmium laser for
treatment of renal stones by Grasso &
Chalik.

6. ...the Ureteroscopic "EVOLUTION"
Rigid ureteroscopes with Rod-lens system & outer
diameter 12-13.5Fr & US/EHL probe
↓
Semirigid ureteroscopes containing fibreoptic
illumination & outer diameter miniaturization
↓
Laser & Pneumatic lithotripters
↓
Flexible URS
↓
Digital URS,Robotic URS & Virtual URS(future
trends)

7. RIGID, SEMIRIGID & FLEXIBLE URS

8. FLEXIBLE URS or RIRS: Definition...
• Surgery within the renal pelvicalyceal
system and parenchyma performed using
instruments introduced in retrograde
fashion through the ureter and lower
urinary tract.
• Advantage: more proximal ureter and
intrarenal collecting system more easily
accessible than conventional URS.

9. RIRS: INDICATIONS
DIAGNOSTIC:
• Evaluation of hematuria
• Evaluation of positive upper tract cytology
• Evaluation of radiographic filling defects or
obstruction
• Surveillance after conservative treatment
of upper tract tumors

10. THERAPEUTIC:
Stone Disease:
• Failed ESWL (stones <1.5 cm)
• RIRS assisted ESWL (stones upto 2.5 cm)
• Radiolucent stones (stones <1.5 cm)
• Concomitant renal and ureteral stones (renal stone <1
cm)
• Calyceal diverticular stones
• Stones with nephrocalcinosis
• Stones with associated anatomic obstruction
• Stones with supravesical diversion
• Rarely, partial staghorn stones

11. Others:
• Treatment of PUJ obstruction
• Treatment of anastomotic strictures
• Treatment of urothelial tumors
• Fulguration of bleeding vessels
• Retrograde percutaneous renal puncture

12. RIRS: CONTRAINDICATIONS
• Patients presenting with ‘high-spiking’
fever & rigors, mental status changes, or
other signs of serious infection.
• Better benefit from a PCN.
• Irrigating pressures within ureter during
endoscopy can lead to pyelovenous and/
or pyelolymphatic back-flow, placing the
patient at risk of septicemia.

13. RIRS: SPECIALLY USEFUL
• Urolithiasis m/m in prepubertal children.
• Pregnant females.
• Bleeding diathesis or
Anticoagulant/Antiplatelet therapy.

14. RIRS: INSTRUMENTATION
Instrumentation for RIRS:
1.Newly designed flexible instrument with dual
deflection
2.Energy sources (EHL, Holmium:YAG laser with
small caliber probes)
3.Flexible accessories including guidewires,
dilators, access sheaths, baskets, graspers,
ureteric catheters and forceps
4.Suction pump
5.Video camera unit
6.Fluoroscopy unit

15. FLEXIBLE URETERORENOSCOPE
• Standard fibreoptic flexible
ureterorenoscopes have a tip size in the
range of 6.75 - 9Fr.
• actively deflectable (primary deflection)
with 120 to 170 degrees of deflection in
one direction and 170 to 270 degrees in
other. Secondary deflection will be passive
or active.
• active secondary deflection allows better
manoeuvrability in LC.
• Working channels of Fr 3.6 - 4 and
standard instruments (e.g. baskets) are Fr
2.2 - 3 in size.

17. HOLMIUM: YAG :LASER
• Lithotriptor of choice for RIRS nowadays.
• Wavelength- 2100nm
• Tissue penetration of 0.4mm.
• Laser fibers caliber- 150-220-360-550μm.
• a 550 μm fiber does not allow flexion, and
forcing it may cause Flex URS rupture.
• 150-220 μm fiber allows all degrees of
flexion of Flex URS, with improved
visibility; but fibers are more fragile and
vulnerable to rupture.

18. • Laser energy is delivered via quartz fibres
to stone surface, where it is absorbed and
turned into heat energy that pulverises the
stone into dust by a "photothermal" effect.
• Stone fragment retrieval with basket /
grasping forceps not necessary.
• Can be safely done in anticoagulated pts.

20. DILATORS & ACCESS SHEATHS
• Use of Access sheath optional during
RIRS.
• Depends on surgeon's personal
preference, stone load and PCS anatomy.
• Size of commonly used Access sheaths:
9/11 Fr and 12/14 Fr.
• Serial Teflon dilators up to size 16 used
for ureteral calibration & dilatation before
introducing the Access sheath over guide-
wire under fluoroscopic guidance.

21. Serial Ureteral Dilators

23. Advantages of Access Sheath:
• Facilitate repeated introduction and withdrawal
of endoscope required for large stone burden;
reduces operative time.
• minimizes distal ureteric trauma, wear on the
ureteroscope.
• Avoid build-up of pressure within PCS especially
when pressurised irrigating fluid is used to
improve vision.
Disadvantages of Access Sheath:
• Requirement of pre-stenting 2-4 weeks due to
less spcious ureters.
• Chances of ureteral injury.

24. BASKETS/EXTRACTORS
• Development of tipless Nitinol basket is vital for success
of RIRS of renal stones.
• Tipless design avoids trauma to mucosa during
intrarenal manipulations.
• Also preserve tip deflection of the flexible
ureterorenoscope.
• Relocation of lower pole stones into renal pelvis or upper
pole calyx with basket greatly enhances the efficiency of
stone fragmentation.
• Extraction of stone fragments via Access sheath should
be considered in large stone burden.

26. RIRS: PREOPERATIVE ASSESSMENT
• CT Urogram/IVU to assess stone load, stone
location and pelvi-calyceal anatomy.
• Informed consent.
• Counselling on treatment options, procedure and
potential complications, with possibilities of
requiring postop stenting, second-look
procedure, auxiliary procedure and failed
procedure are all thoroughly explained.
• Preoperative urine cultures.
• General anesthesia & prophylactic induction
antibiotic.

27. RIRS: PATIENT POSITION
• Dorsal lithotomy position.
• Padding of all pressure points.

28. RIRS: TECHNIQUE
Essential points of RIRS technique:
• Safety guide-wire inserted up to renal pelvis;
• Ureteric dilatation and use of Access sheath as preferred
/ indicated;
• Flexible ureterorenoscope "rail-roaded" up to renal pelvis
over double-flexible tips guide-wire under fluoroscopic
and endoscopic guidance;
• Systematic inspection of the pelvi-calyceal system to
identify pathology endoscopically under saline irrigation
(pressurised irrigant as required, preferably with Access
sheath) and aided with fluoroscopy / RP as required;
• Commence lithotripsy with Holmium laser;
• Stone relocation / retrieval with basket as indicated;
• Assess stone clearance with endoscopy/fluoroscopy/RP;
• Placement of double-J ureteric catheter as indicated.

29. • Post-operative ureteric stenting is optional.
• Routine ureteric stenting after uncomplicated
ureteroscopy is not necessary.
• Indications for post-operative ureteric stenting
include
ureteric injury,
ureteric stricture,
solitary kidney,
renal insufficiency and
a large residual stone burden.

30. RIRS: Access to the Upper Urinary
Tract
• Dilation of ureteral orifice
& “optical dilation” with
9.5 Fr rigid ureteroscope.

33. Access to lower pole using secondary
deflection of scope

34. RIRS: SCREENSHOTS...

37. ALGORITHM FOR RENAL STONE
DISEASE

38. RIRS: COMPLICATIONS
Intraoperative complications:
• failure to access (ureter, kidney, or stone),
• stone migration into ureteral wall,
• failure to fragment stone,
• mucosal trauma,
• ureteral perforation,
• devastating complication like ureteral
avulsion due to use of excessive force.

39. Post-operative minor complaints:
• hematuria,
• renal colic (small residual stone
fragments, blood clot),
• pyelonephritis,
• urinoma.
• Ureteral stricture is one of delayed
complication.

40. FOLLOW-UP
• First follow-up visit scheduled about 2
weeks post-op.
• Treatment outcome assessed with a KUB
radio-graph or additional imaging.

41. LIMITATIONS OF RIRS
Technical difficulties due to deficient quality
of instruments used, such as
ureteroscopes offering
• scanty visibility,
• poor illumination,
• a small working channel,
• deficient quality of forceps and baskets,
etc. and
• limited life of instruments with high cost to
Service, especially if used by several
urologists.

42. FUTURE TRENDS...
DIGITAL URS:
• Humphreys MR et al demonstrated the beauty of
digital ureterorenoscopy.
• The distal tip objective is a CMOS imaging
sensor coupled to a prism, utilising light emitting
diodes(LED) as the light source, which gives
superb vision within the PCS.
• Further studies required to show improved
outcome.

44. FLEXIBLE ROBOTIC URS:
• Potential advantages- an increased range
of motion, instrument stability, and
improved ergonomics.
• Avoids excessive strain on the surgeon
who keeps the flexible uretroscope in
deflection for prolonged periods to
approach the target.

46. VIRTUAL URETEROSCOPY:
• Computer driven reconstruction of the
endoscopic view of ureter may prove a
useful noninvasive way of surveilling the
urinary tract.

48. CONCLUSION
• RIRS is an integral part of armamentarium of
urologists.
• A valuable tool both in the treatment of renal
stones refractory to ESWL and also for
diagnosis of upper tract pathology.
• With a refinement of technique, complications
like stricture, perforation and extravasation can
be minimized.
• Future developments of RIRS are digital imaging
to improve the quality of vision and robotics to
improve manoeuvrability.

49. THANK
YOU !!!