Strategies for non-medical management of renal calculi have evolved significantly over time. Originally, surgical removal of stones was highly morbid. Developments in fiber optics, imaging, and lithotripsy led to minimally invasive techniques like ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), and extracorporeal shock wave lithotripsy (SWL). Treatment selection is based on stone burden, location, and composition. For stones under 1cm, SWL or URS are generally first-line. For 1-2cm stones, URS or SWL are used, while PCNL may be used for larger or complex cases. PCNL is the standard

1. Strategies for non – medical
management of renal calculi
Dr. Manoj Kumar Deepak
Urology resident
SRM Hospital and medical college

2. “An acute pain is felt in the kidney, the loins, the flank
and the testis of the affected side;
the patient passes urine frequently; gradually the urine is
suppressed. With the urine, sand is passed.”
- Described by Hippocrates..

3. History – Evolution of Non medical treatment modalities
 In centuries that followed Hippocrates, there was little scientific
progress in the surgical therapy for patients with renal calculi.
 The alleged first account of a surgical attempt to remove a
stone from a patient’s kidney is the case of the French archer of
Bagnolet.
 This is a tale of a condemned man with a renal calculus who
agreed to allow surgery on the affected kidney with the
condition that if he survived he would be freed.
 According to the anecdote, the man survived the open surgical
stone removal and was freed in 1474 (Herman, 1973).

4. History – Evolution of Non medical treatment modalities
The first verifiable account of renal stone
surgery was in 1550, when Cardan of Milan
opened a lumbar abscess on a young girl
and removed 18 calculi (Desnos, 1972).
1880 – First nephrolithotomy by
Henry Morris of England.

5. History – Evolution of Non medical treatment modalities
1879 - first
pyelolithotomy by
Heineke.
Josef Hyrtl in 1882 and
Max Brödel in 1902
described a relatively
avascular plane
Bleeding was however
a major complication
all these techniques.

6. History – Evolution of Non medical treatment modalities
1965 - Gil- Vernet Extended pyelolithotomy.
Eventually this approach to the renal
collecting system became the procedure of
choice for treatment of the majority of renal
pelvic calculi.
1968 Smith and Boyce described anatrophic
nephrolithotomy, a procedure that derived
its name from the technique of incising the
renal parenchyma along the avascular
between the anterior and posterior vascular
distributions.
Although stone-free rates of these surgical
techniques were excellent, morbidity was
significant, and the search for new
techniques and technologies continued.

7. RISE OF ENDOUROLOGY - History
 One of the core tenets of renal stone surgery is to maximize stone removal while minimizing
patient morbidity.
 With time we saw developments leading minimally invasive surgical techniques with technologic
advances in the fields of fiber optics, radiographic imaging, and lithotripsy.
 And with it we saw the emergence of modern techniques of ureterorenoscopy (URS),
percutaneous nephrolithotomy (PCNL), and extracorporeal shock wave lithotripsy (SWL).
In 1979 Arthur Smith defined the term endourology as closed
controlled manipulation within the genitourinary tract.

8. Ureterorenoscopy
 Aided by the child’s secondary ureteral dilation, Young was able to
advance the cystoscope to the level of the renal pelvis, thus
becoming the first urologist to view the intrarenal collecting system
endoscopically
In 1912 Hugh Hampton Young introduced a pediatric cystoscope into the massively
dilated ureter of a child with posterior urethral valves (Young and McKay, 1929).

9. FLEXIBLE SCOPE
By 1957 Curtiss and Hirschowitz – created the first flexible
endoscope ( by combining large number of glass fibers)

10. Percutaneous Stone Removal
 During the same time period as development of SWL, PCNL was developed.
Rupel and Brown (1941) of
Indianapolis, who removed a stone
through a previously established
surgical nephrostomy.
In 1976 Fernstrom and Johannson first
first reported the establishment of
percutaneous access with the specific
intention of removing a renal stone.

11. Extracorporeal Shock Wave
Lithotripsy
 In the early 1980s SWL was developed.
 Based on the phenomenon that sound waves can be focused.
 The ancient Greeks, as taught by Dionysius, used this
knowledge to construct vaults that allowed them to overhear
the conversations of their imprisoned enemies.

12. SWL – the evolution
 Engineers at Dornier Medical Systems in the then
West Germany, during research on the effects of
shock waves on military hardware.
 The possibility of applying shock wave energy to
human tissue was discovered when, by chance, a test
engineer touched a target body at the very moment
of impact of a high-velocity projectile.
 The engineer felt a sensation similar to an electric
shock, although the contact point at the skin showed
no damage at all.

13. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones

14. FACTORS INFLUENCING TREATMENT SELECTION

15. FACTORS INFLUENCING TREATMENT SELECTION

16. NATURAL HISTORY -
Asymptommatic Renal Stones (Non stag horn type)
 A review of the known behavior of such stones suggests that many will grow over time, become
symptomatic, and ultimately require treatment.
 Incidence of asymptomatic renal stones ~ approximately 10%.
 Before the era of minimally invasive stone treatments, asymptomatic and minimally symptomatic
stones were not actively removed, given the high morbidity associated with treatment.
 Currently, with the expanding availability of SWL and URS then scenario has changed.
DO THEY NEED ACTIVE MANAGEMENT??

17. NATURAL HISTORY -
Asymptommatic Renal Stones (Non stag horn type)
 Hubner and Porpaczy (1990) reviewed the natural history of renal stones in 62 patients managed
before the advent of SWL or widespread URS.
 Spontaneous passage was seen in 16%, whereas 40% required surgical intervention.
 Stone growth was noted in 45% of patients, UTI in 68%, and pain developed in 51%.
 Similar results were found by
 Glowacki et al. (1992),
 Keeley et al. (2001)
 Burgher et al. 2004
 Inci (2007)
 Boyce 2010
 Koh 2012
 Yuruk 2010
 Kahng 2013

18. TREATMENT RECOMMENDATION -
Asymptommatic Renal Stones (Non stag horn type)
YES !!
THEY NEED TREATMENT..

19. TREATMENT RECOMMENDATION -
Asymptommatic Renal Stones (Non stag horn type)
 Overall stone disease progression (stone-related symptoms or stone growth), occurs in as many
as 50% to 80% of cases,
 Second, spontaneous stone passage occurs about 15% of the time and is more likely in stones 5
mm in size or smaller.
 Third, larger stones and those located in the renal pelvis are more likely to become symptomatic.
 Finally, the risk of eventual surgical intervention for initially asymptomatic renal stones is
approximately 10% to 20% at 3 to 4 years after the stones are initially discovered.

20. NATURAL HISTORY - Staghorn Calculi
 These are large renal stones that occupy most or all of the
renal collecting system.
 The name arises the look resembling the antlers of a deer or
stag on imaging.

21. NATURAL HISTORY - Staghorn Calculi
 Before the era of endourology, staghorn stones were not
always treated, because of the surgical morbidity
 Untreated, staghorn stones - recurrent UTIs, urosepsis, renal
functional deterioration, renal loss, end-stage renal disease,
and a higher likelihood of death.
 Complete renal function loss in 50% of affected kidneys can
occur after 2 years without treatment.
 AUA guideline:
 Recommends for the surgical treatment of staghorn stones in patients healthy enough
for treatment, with complete stone removal as the therapeutic goal.

22. TREATMENT
APPROACHES
SCENARIOS

23. Pretreatment Assessment
CT KUB; USG KUB; MRI
(Sensitivity & specificity of 95%; 45%; 80% resp)
CBC, RFT, URINE RE, URINE C/S
STONE FACTORS - STONE BURDEN (total number and size of stones), STONE LOCATION,
and STONE COMPOSITION.

24. MANAGEMENT BASED ON
STONE BURDEN

25. I) Treatment Decision by Stone Burden
 The total kidney stone burden, or total volume of stone(s) requiring treatment, is the most
important factor influencing treatment decisions.
 Stratifications of stone burden:

26. TREATMENT
APPROACHES
SCENARIO 1a
Kidney Stone Burden Up to 1 cm

27. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones

28. Kidney Stone Burden Up to 1 cm –
Options 1: SWL
 The majority (50% to 60%) of solitary kidney stones are 1 cm or less in diameter, and many of
them are asymptomatic.
 However they warrant treatment.
SWL has been considered first-line treatment

29. Kidney Stone Burden Up to 1 cm –
Options 1: SWL
80% to 88% for stones in the renal pelvis and ureteropelvic junction (UPJ)
~ 70% upper and middle calyces
35% to 69% for lower pole stones
Clearance rates

30. SWL CONTRA INDICATIONS

31. TREATMENT
APPROACHES
SCENARIO 1b
Kidney Stone Burden Up to 1 cm – with
Contra indications to SWL

32. Kidney Stone Burden Up to 1 cm –
Option 2: URS (RIRS)
 URS> SWL
 Recent literature suggests that URS in experienced hands has an excellent safety profile, with
stone-free rates and treatment efficiency superior to SWL for small renal stones.
 AUA AND EAU
Flexible URS is now considered an alternative first-line
therapy for kidney stone burden 1 cm or less in size

33. Kidney Stone Burden Up to 1 cm –
Option 3: PCNL
 Reserved for failures of SWL and URS
 Anatomic considerations
 Acute infundibulopelvic angles
 Calyceal diverticula.
 Similar stone-free rates but with an overall lower complication rate.
“mini” and “micro” PCNL procedures >> Traditional PCNL

34. TREATMENT APPROACHES
– SUMMARY
Kidney Stone Burden Up to 1 cm

35. Kidney Stone Burden Up to 1 cm –
 Offer SWL as first line - since it is non invasive and effective.
 SWL is not possible or contra indicated
 If available and expertise feasible
 In SWL/ URS failed cases or cases with anatomic abnormalities offer micro/ Mini PCNL.
– URS(RIRS)

36. TREATMENT
APPROACHES
SCENARIO 2
Kidney Stone Burden of 1 - 2 cm

37. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones

38. Kidney Stone Burden Between 1 and 2 cm
 Stone specific and anatomic factors must be carefully considered when weighing the relative
outcomes and invasiveness of each procedure.

39. FACTORS INFLUENCING TREATMENT

40. Kidney Stone Burden Between 1 and 2 cm –
OPTION 1: URS (RIRS)
 For stones between 1 cm and 2 cm that are not located in the lower pole,
 Current AUA and EAU stone guidelines:
Recommend URS (first line and
SWL as alternative first-line therapeutic options.

41. As a general principle, the
efficacy of SWL decreases
while the
need for ancillary
procedures and re-
treatment increases as
stone
burden enlarges
SWL

42. Kidney Stone Burden 1 - 2 cm –
Option 3: PCNL
 PCNL accomplishes higher stone-free rates and requires fewer auxiliary procedures
than SWL or URS for renal stones
 Disadvantages: Greater invasiveness
 Though the success rates were highest for PCNL (91% to 98%) compared to the URS
(87% to 91%), and SWL (66% to 86%) there is a higher rate of significant complications
of PCNL.
“mini” or “micro” PCNL procedures and Traditional PCNL

43. TREATMENT APPROACHES
– SUMMARY
Kidney Stone Burden 1- 2 cm

44. Kidney Stone Burden 1-2 cm
 Offer URS(RIRS) as first line for non lower pole stones since it is relatively less invasive
and effective.
 Offer SWL as an alternative first line therapy.
 In failed cases or cases with anatomic abnormalities/ Lower pole stones offer micro/
Mini/ traditional PCNL.

45. TREATMENT
APPROACHES
SCENARIO 3
Kidney Stone Burden of > 2 cm

46. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones

47. Kidney Stone Burden Greater Than 2 cm.
OPTION 1: PCNL
 PCNL should be considered first-line therapy for kidney stone burdens 2 cm and greater
 The success of PCNL is relatively independent of stone location and stone composition.
 Clearance of lower pole stones is also excellent with PCNL (as high as 95% in the Lower Pole I
study)

48. Kidney Stone Burden Greater Than 2 cm.
OPTION 1: PCNL
 Overall complication rates between 20% and 30% have been reported.
 Stone-free rates can be improved and blood loss decreased when flexible nephroscopy is used to
augment standard PCNL

49. TREATMENT
APPROACHES
SCENARIO 3a
Contraindications to PCNL
Kidney Stone Burden of > 2 cm

50. Kidney Stone Burden Greater Than 2 cm.
OPTION 2: URS (RIRS)
 Significant comorbidities or contraindications namely - frailty, coagulopathy, refusal of
transfusion.
 In such patients, although less efficient and potentially requiring multiple stages, less
invasive alternatives such as URS should be considered.

51. TREATMENT APPROACHES
– SUMMARY
Kidney Stone Burden > 2 cm

52. Kidney Stone Burden > 2 cm
 Offer PCNL as first line irrespective of stone location and composition though it is more
invasive but most effective.
 Offer URS – Single/ Multiple staged as an alternative when contraindications to PCNL
exist.

53. MANAGEMENT OF STAG HORN
STONES

54. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones
OPEN NEPHROLITHOTOMY

55. STAG HORN STONE –
Option 1: PCNL
 PCNL is the method of choice for treating partial and complete staghorn kidney stones
 The AUA Nephrolithiasis Guideline Panel and the EAU urolithiasis guideline:
Recommend PCNL as the first-line therapy for
staghorn stones

56. STAG HORN STONE –
Option 1: PCNL
 The aim is to render the patient stone free while minimizing morbidity.
 However PCNL in staghorn calculi is challenging to treat, frequently require multiple
percutaneous access tracts and/or multiple stages, and have high treatment-related
morbidity.
 The use of flexible nephroscopy during PCNL can improve stone clearance and reduce
the number of access tracts necessary by allowing access to calyces unreachable with
rigid instruments
 Flexible nephroscopy is considered a guideline recommendation by the AUA (Assimos
et al., 2016).

57. Combination therapy vs Monotherapy
 Combination therapy with multiple endourologic modalities has been used as an alternative to
PCNL monotherapy.
 Sandwich therapy was popularized in the 1990s, staghorn stones were treated first with
 However, outcomes for combination therapy were comparable with those attained with PCNL
monotherapy or open nephrolithotomy.
PCNL,
SWL for residual or
inaccessible stones,
Finally with another
percutaneous procedure

58. STAG HORN STONE –
Option 2: URS(RIRS)
 Indications:
 Simple partial staghorn stones
 Stones located in favorable anatomic location (non lower pole)
 Contraindications to PCNL.

59. STAG HORN STONE –
Option 3: Laparoscopic and robotic-assisted techniques
 Laparoscopic and robotic-assisted techniques have been described in small series for the
treatment of complete, or nearly complete, staghorn stones.
 Although these techniques have been shown to be feasible, actual stone-free rates were
relatively low (29% to 67%), and the techniques provide no obvious advantage over PCNL for
routine staghorn stones.

60. STAG HORN STONE –
Option 4: Open Nephrolithotomy
 Reserved for rare instances in which complicating factors make PCNL impossible or unlikely to
achieve reasonable stone clearance within an acceptable number or combination of procedures.
 Stone-free rates for open surgery have been reported to be as high as 85%; however, since the
rise of endourology and PCNL, superior stone-free rates are routinely achievable with PCNL

61. MANAGEMENT BASED ON
STONE LOCALISATION

62. Treatment Decision by Stone Localization
 Second most important factor after stone burden.
 Especially for stones between 1 cm and 2 cm.
 Location of stones within the kidney can be simplified to two groups:
LOWER POLE
PCNL URS
NON LOWER POLE
SWL or URS
PCNL
(Mid pole > Upper)

63. LOWER POLE STONES
 Lower pole stones are the most difficult to treat, especially when the lower pole
anatomy is unfavorable.
 Unfavourable factors are:
Acute Infundibulopelvic Angle
Long Infundibular Length
Narrow Infundibular Width

64. MANAGEMENT BASED ON
STONE COMPOSITION

65. Treatment by Stone Composition
 Important in SWL, whereas URS, PCNL, and laparoscopic and open stone surgery
appear to be only minimally affected.
 In general, cystine, calcium phosphate (specifically “brushite”), and calcium oxalate
monohydrate stones are the most resistant to SWL.
 In addition, SWL fragmentation of such stones results in relatively larger stone
fragments, affecting stone clearance.
 Recognition of this limitation should prompt consideration of another modality (e.g.,
URS or PCNL).

66. Treatment by Stone Composition –
Matrix stones
 Matrix renal stones are rare.
 Predominantly (approximately 65%, range 42% to
84%) composed of organic proteins, sugars, and
glucosamines, whereas other crystalline calculi
have only minimal organic material (2.5%)
 These stones are soft,gelatinous, and relatively
amorphous.
PCNL is the preferred treatment

67. MANAGEMENT OF STONES IN
RENAL ANATOMIC
ABNORMALITIES

68. Renal Anatomic Factors-
Stones & Ureteral Pelvic Junction Obstruction
 Associated with kidney stones up to 20% to 30% of the time
 It is vital to, before undertaking any surgical correction, try to
distinguish if the UPJO is the underlying disorder with
subsequent renal stone formation, or if a renal pelvis or UPJ
stone provoked edema at the UPJ, giving the misleading
appearance of UPJO when none actually exists.

69. Strategies Used To Treat UPJO With Concomitant
Kidney Stones
 Options Available are:
PCNL with
antegrade
endopyelotomy,
Pyeloplasty with
pyelolithotomy or
nephrolithotomy,
Retrograde
endopyelotomy with
URS stone removal

70. Calyceal diverticula with stones
 Calyceal diverticula are rare,
 Incidence of 0.2% to 0.6%.
 Usually asymptomatic and require no treatment;
 Diverticular stones associated with pain, recurrent infections, hematuria, or a decline in
renal function warrant treatment.

71. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones

72. CALYCEAL DIVERTICULAR
stones
PCNL
FIRST LINE
URS (RIRS)
1st line if <2 cm diverticula
upper or mid pole calyx
LAPAROSCOPIC/ ROBOTIC
Consider in anteriorly
placed calyceal diverticula;
Thin overlying parenchyma
SWL
Not used as a first line

73. Stones in horseshoe Kidneys and Renal
Ectopia
 MC Composition - calcium oxalate,
 MC locations are the renal pelvis and posterior lower pole calyces

74. The urologists armamentarium
SWL URS
PCNL laparoscopic or robotic-assisted stone
surgery
For surgical treatment
of kidney stones

75. Stones in horseshoe Kidneys and Renal
Ectopia
<15 mm (non
lower pole)
SWL URS
>15 mm
PCNL
FAILED

77. Thank You