PCNL A Global Perspective Dr CW Wong Division of Urology Department of Surgery Pamela Youde Nethersole Eastern Hospital

PCNLPCNLA Global PerspectiveA Global Perspective

Dr CW WongDr CW WongDivision of UrologyDivision of Urology

Department of SurgeryDepartment of SurgeryPamela Youde Nethersole Eastern HospitalPamela Youde Nethersole Eastern Hospital

Introduction and historyIntroduction and history PCNL: what is it?PCNL: what is it? IndicationsIndications Imaging modalities for percutaneous accessImaging modalities for percutaneous access Dilatation of the nephrostomy tractDilatation of the nephrostomy tract Mini-perc techniqueMini-perc technique Mode of stone fragmentationMode of stone fragmentation Chinese MPCNL: PYNEH experience Conclusion

Introduction and historyIntroduction and history 18651865 Thomas Hillier described first Thomas Hillier described first

percutaneous nephrostomypercutaneous nephrostomy

19551955 Willard Goodwin & associates reported Willard Goodwin & associates reported their experience with percutaneous their experience with percutaneous nephrostomies in 16 patientsnephrostomies in 16 patients

19761976 Fernstrom & Johansson described a Fernstrom & Johansson described a procedure through which a renal pelvic procedure through which a renal pelvic calculus could be extracted through a calculus could be extracted through a percutaneous tractpercutaneous tract

Early 80sEarly 80s Percutaneous nephrolithotomy Percutaneous nephrolithotomy gained gained widespread popularitywidespread popularity

PCNL & ESWLPCNL & ESWL

With the advent of With the advent of ESWLESWL in the mid 80s, in the mid 80s, the indications for percutaneous stone the indications for percutaneous stone extraction were narrowedextraction were narrowedAs the As the limitations of ESWLlimitations of ESWL were recognised, were recognised,

percutaneous surgery once again rose in percutaneous surgery once again rose in popularity with a redefined role in stone popularity with a redefined role in stone managementmanagement

PCNL: what is it?PCNL: what is it?

Percutaneous nephrolithotripsyPercutaneous nephrolithotripsyRetrograde pyelogramRetrograde pyelogramTract formation for renal accessTract formation for renal access

PCNL: what is it?PCNL: what is it?

Stone fragmentation & retrievalStone fragmentation & retrieval

IndicationsIndications PCNL is the preferred treatment for PCNL is the preferred treatment for

Large stone burden 2 cm or 1.5 cm for lower calyceal stones Staghorn stones Stones that are difficult to disintegrate by ESWL

(calcium-oxalate monohydrate, brushite, cystine) Stones refractory to ESWL or ureteroscopy Urinary tract obstructions that need simultaneous

correction (e.g. PUJ obstruction) Malformations with reduced probability of fragment

passage after ESWL (e.g. horseshoe or dystopic kidneys, calyceal diverticula)

Obesity

EAU Guidelines on Urolithiasis 2001

Imaging modalities for Imaging modalities for percutaneous accesspercutaneous access

Image guidedImage guidedFluoroscopyFluoroscopyUSGUSG


FluoroscopyFluoroscopyMost commonly employedMost commonly employedUse of 2-plane fluoroscopy to achieve Use of 2-plane fluoroscopy to achieve

accurate needle entryaccurate needle entryRadiation safety: patient, surgeons, staffRadiation safety: patient, surgeons, staff


UltrasonographyUltrasonography::The simplest & most directThe simplest & most directMinimises radiation exposureMinimises radiation exposureAllows imaging of intervening structures Allows imaging of intervening structures

between skin and kidneybetween skin and kidneySonographic identification of the puncture Sonographic identification of the puncture

needle may be technically demandingneedle may be technically demanding Inability to clearly visualise and manipulate a Inability to clearly visualise and manipulate a

guidewire once it is placed through the guidewire once it is placed through the percutaneous access tractpercutaneous access tract

Dilatation of the nephrostomy tractDilatation of the nephrostomy tract

Progressive fascial dilatorsProgressive fascial dilatorsMetal coaxial dilatorsMetal coaxial dilatorsBalloon dilation cathetersBalloon dilation catheters

Dilation of the nephrostomy tractDilation of the nephrostomy tract

Fascial dilatorsFascial dilatorsProgressively larger Teflon tubes designed to Progressively larger Teflon tubes designed to

slide over a 0.038 inch GWslide over a 0.038 inch GWSize ranging from 8 to 36 FrSize ranging from 8 to 36 Fr Inserted in a rotating, screw-type fashionInserted in a rotating, screw-type fashionAdvantages:Advantages:

SafeSafeIdeal for dilation of fibrous tractsIdeal for dilation of fibrous tracts

Disadvantages:Disadvantages:Dependence on the integrity of the GWDependence on the integrity of the GW


Metal coaxial dilatorsMetal coaxial dilators Stainless steel, mounted together in a telescopic Stainless steel, mounted together in a telescopic

fashionfashion 8 Fr hollow guide rod that slides over a GW8 Fr hollow guide rod that slides over a GW A set of six metal tubes ranging in diameter from 9 to A set of six metal tubes ranging in diameter from 9 to

24 Fr, each adapting exactly to the lumen of the next 24 Fr, each adapting exactly to the lumen of the next dilatorsdilators


Balloon dilation cathetersBalloon dilation cathetersTo achieve tract dilation in a single stepTo achieve tract dilation in a single stepAvoid the need for serial dilationAvoid the need for serial dilationGenerate lateral compressive forces, Generate lateral compressive forces,

theoretically less traumatictheoretically less traumaticDrawback: relative inability to dilate dense Drawback: relative inability to dilate dense

fascial tissue or scar tissuefascial tissue or scar tissue

Mini-perc techniqueMini-perc technique

Use of 13 to 20 Fr tractUse of 13 to 20 Fr tractSmaller volume of renal parenchyma Smaller volume of renal parenchyma

dilated, leading to decrease in blood loss dilated, leading to decrease in blood loss and post-op painand post-op pain

Lahme et al Eur Urol. 40(6):619-24Lahme et al Eur Urol. 40(6):619-24

Stone fragmentationStone fragmentation

Electrohydraulic LithotripsyElectrohydraulic LithotripsyFragments stones with shock waves Fragments stones with shock waves

generated by an underwater electrical generated by an underwater electrical dischargedischarge

Narrow margin of safety owing to the risk of Narrow margin of safety owing to the risk of damage to ureteral mucosa and ureteral damage to ureteral mucosa and ureteral perforationperforation


Holmium:YAG laserHolmium:YAG laser lithotripsy lithotripsyOccurs primarily through a photothermal Occurs primarily through a photothermal

mechanism that causes stone vaporisationmechanism that causes stone vaporisationHighly absorbed by waterHighly absorbed by waterZone of thermal injury associated with laser Zone of thermal injury associated with laser

ablation ranges from 0.5 to 1.0 mmablation ranges from 0.5 to 1.0 mmAble to fragment all stonesAble to fragment all stones

regardless of compositionregardless of composition


Ballistic LithotripsyBallistic Lithotripsy A “jackhammer” effectA “jackhammer” effect Swiss LithoClastSwiss LithoClast Effective means for stone fragmentation in the entire Effective means for stone fragmentation in the entire

urinary tract with wide margin of safetyurinary tract with wide margin of safety Relatively high rate of stone propulsionRelatively high rate of stone propulsion


Ultrasonic lithotripsyUltrasonic lithotripsyProbe tip causes the stone to resonate at high Probe tip causes the stone to resonate at high

frequency and breakfrequency and breakWhen placing it on compliant tissues such as When placing it on compliant tissues such as

the urothelium, damage is minimal because the urothelium, damage is minimal because the tissue does not resonate with the the tissue does not resonate with the vibrational energy vibrational energy

Minimally Invasive PCNL (MPCNL) according to the Chinese Method:

A Comparison with Traditional PCNL

CW Wong, TC Fung, CW Fan, SM Hou, SK Li

Division of Urology, Department of SurgeryPamela Youde Nethersole Eastern Hospital

Hong Kong

Chinese MPCNLChinese MPCNL Minimally invasive PCNL, according to the Minimally invasive PCNL, according to the

Chinese methodChinese method

MPCNLMPCNL First described by First described by LahmeLahme, Germany in 2001 , Germany in 2001

Eur Urol. 40(6):619-24Eur Urol. 40(6):619-24

The termThe term Chinese MPCNLChinese MPCNL Coined by Coined by Dr SK LiDr SK Li, PYNEH at ELSA 2005, PYNEH at ELSA 2005 Based on the approach described by Based on the approach described by Professor Li Professor Li

XunXun, Guangzhou, China, Guangzhou, China

Essential featuresEssential features

PuncturePuncture::Kidney puncture based on pre-op imaging Kidney puncture based on pre-op imaging

and tactile feedbackand tactile feedbackMinimal use of fluoroscopyMinimal use of fluoroscopySize Fr 18 tractSize Fr 18 tract

Stone fragmentation:Stone fragmentation:LithoClastLithoClast®® (using 1 mm probe) (using 1 mm probe)

Stone removal:Stone removal:Mainly by retrograde saline flushingMainly by retrograde saline flushing

Puncture & tract dilatationPuncture & tract dilatation

Patient in prone position

puncture site in 11th intercostal space

12th rib

11th rib

Miniaturized endoscopeMiniaturized endoscope

Olympus® slim compact cystoscope

Pressurized irrigationPressurized irrigation

350mmHg

Access to all calyces & ureterAccess to all calyces & ureter

MPCNL: the techniqueMPCNL: the technique

MethodMethod

PatientsPatients16 consecutive cases of staghorn stones16 consecutive cases of staghorn stonesUnderwent Chinese MPCNL by one single Underwent Chinese MPCNL by one single

SurgeonSurgeon

Statistical analysisStatistical analysisResults were retrospectively compared to that Results were retrospectively compared to that

of the last 20 cases of traditional PCNL using of the last 20 cases of traditional PCNL using Fr 24-28 sheathFr 24-28 sheath

Results – stone characteristicsResults – stone characteristics

Chinese Chinese MPCNLMPCNL PCNLPCNL

Stone diameter (cm) Stone diameter (cm) 3.79 3.79 1.3 1.3 3.36 3.36 0.94 0.94

Stone area (mmStone area (mm²²) ) 784.8784.8 926.3926.3

Type n (%) Type n (%)

BorderlineBorderline 5 (5 (3131)) 13 (13 (6565))

PartialPartial 9 (9 (5656)) 5 (5 (2525))

Complete Complete 2 (2 (1313)) 2 (2 (1010))

Results – Results – operative parameters & outcomeoperative parameters & outcome


OR time (minutes) OR time (minutes) 94.794.7 122122

Length of stay (day) Length of stay (day) 6.76.7 7.67.6

Stone clearance n (%) Stone clearance n (%)

CompleteComplete 8 (8 (5050)) 12 (12 (6060))

Residual Residual ≤ ≤ 4 mm 4 mm 2 (2 (12.512.5)) 2 (2 (1010))

Residual > 4 mmResidual > 4 mm 6 (6 (37.537.5)) 6 (6 (3030))

Auxiliary treatmentAuxiliary treatment 55 66

Results - complicationsResults - complications


Complications n (%)Complications n (%)

TransfusionTransfusion 1 (1 (6.36.3)) 5 (5 (2525))

UTIUTI 1 (1 (6.36.3)) 2 (2 (1010))

Pleural effusionPleural effusion 1 (1 (6.36.3)) 00

TOTALTOTAL 3 (18.9)3 (18.9) 7 (35)7 (35)

Advantages of Chinese MPCNLAdvantages of Chinese MPCNL

Miniaturised endoscope allows Miniaturised endoscope allows good calyceal good calyceal and ureteric accessand ureteric access even with middle calyceal even with middle calyceal puncturepuncture

Middle calyceal puncture at 11th intercostal Middle calyceal puncture at 11th intercostal space space avoids riskavoids risk associated with supra-11th associated with supra-11th upper pole calyceal punctureupper pole calyceal puncture

A Fr 18 percutaneous tract A Fr 18 percutaneous tract minimises trauma minimises trauma withwith less blood lossless blood loss

ConclusionConclusion PCNL is a good and valuable method for PCNL is a good and valuable method for

removal of renal calculiremoval of renal calculi Different techniques of percutaneous renal Different techniques of percutaneous renal

access, tract dilation and stone fragmentation access, tract dilation and stone fragmentation have been developedhave been developed

Mini-perc is an evolving PCNL techniqueMini-perc is an evolving PCNL technique An effectiveAn effective treatment option even for staghorn stone treatment option even for staghorn stone Good stone clearanceGood stone clearance Good calyceal and ureteric accessGood calyceal and ureteric access A A safesafe option option Reducing traumaReducing trauma Less transfusion requirementLess transfusion requirement

The needle is being advanced with the C-arm at 30 degrees. A, Use of a clamp to reduce radiation exposure to the hands of the urologist. B, The C-arm is rotated back to the vertical position, and the depth of the needle is ascertained.

Documents

PCNL A Global Perspective Dr CW Wong Division of Urology Department of Surgery Pamela Youde Nethersole Eastern Hospital