3. • By the end of this presentation our PG’s
wil be able to know common indication,
procedure and position, different
techniques and complications.
4. Percutaneous Nephrolithotomy
• is a minimal-invasive procedure to
remove stones from the kidney by
a small puncture wound (up to
about 1 cm) through the skin.
• It is most suitable to remove stones
of more than >2 cm in size and
which are present near
the pelvic region.
• PCNL attains stone free rates of
upto 95%
• AUA guidelines recommend PCNL
as a treatment of choice for
staghorn calculi.
• It has been invented in 1976 by
Fernstrom and Johansson[1]
5. INDICATIONS
Percutaneous nephrolithotomy (PNL)
is
recommended by the Guidelines of the
European Association of Urology
for the
following indications:
• 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).
• Urinary tract obstructions that need simultaneous correction (e.g.
PUJ obstruction).
• Malformations with reduced probability of fragment passage after
ESWL (e.g. horseshoe , calyceal diverticula)
• Obesity
6.
7. • PCNL is contraindicated if patient has
uncorrectable coagulopathy.
• Antiplatelet medications like aspirin should be
discontinued 7 days before operation.
8. Anaesthesia and Positioning
• Preferably performed under
a. General Anesthesia
b. Spinal or
c. Local Anesthesia
The positions generally preferred for puncture are:
1. Prone Oblique
2. Completely Prone
3. Supine
9.
10. Surgical Technique
• Pre-operative urographic assessment with
computed tomography is helpful in planning
the operation.
• Any urinary tract infection needs prior
treatment with appropriate antibiotic, and a
temporary percutaneous nephrostomy can be
inserted to drain an obstructed and infected
pelvicalyceal system beforehand.
12. BULL’S EYE TECHNIQUE
• also called the Eye of the Needle technique.
• The target calyx is identified with the C arm at 0° in
the axial plane.
• Then the C arm is rotated 30° towards the surgeon
and the calyx to be punctured would appear end on
the fluoroscopy screen.
• A tilt of 5°-10° in the caudal direction for the lower
pole or in the cranial direction for the upper pole
may be necessitated to have a circular end on
appearance of the target posterior calyx.
13.
14.
15.
16.
17. • The position on the skin overlying the
selected calyx is then marked and the
puncture initiated.
• It is seen as a Bull’s eye (as a dot) on the
fluoroscopy screen
• It is then advanced to puncture the calyx.
• Free efflux of urine confirms the position in
the collecting system.
18. BULL’S EYE TECHNIQUE
To perform the “eye-of-the-needle” technique,
first inspect the kidney with the fluoroscopy unit directly above the
patient (directed vertically 0 degree) and select the desired calyx.
Next, rotate the top of the fluoroscopic unit 30 degrees toward the
operator,
Place the tip of a hemostat on the skin and move it until it is directly
over the desired calyx.
Mark this site and make an incision.
Place the tip of the access needle into this incision, and
then move the shaft of the needle while keeping the tip in place until
the needle is directly in line with the axis of the fluoroscopy unit;
doing so gives the appearance of a “bull’s eye” with the hub of the
needle (appearing as a circle) around the shaft (which appears as a
dot).
19.
20.
21.
22.
23. TRIANGULATION TECHNIQUE
• technique of using two known points of reference to locate a third
unknown point
• guided by biplanar fluoroscopy.
• The medial and lateral plane is assessed with the C arm at 0°.
• The depth is assessed by rotating the C arm in the cranial or caudal
direction by 30°.
• The target calyx is identified with the C arm at 0°.
• Then the line of puncture is aligned with the infundibulum
• With the C arm at 0° the needle is introduced through the skin incision.
• The left and right, i.e., the mediolateral adjustments are made and the
needle is aligned with calyx.
• Then the C arm is rotated 30°, towards the head end for lower pole
punctures and towards the foot end for upper pole punctures.
• The needle is then oriented in the up and down, i.e., the cephalo-caudal
position so that the orientation is again towards the desired calyx.
24. • If the needle position in the medial-lateral and
cephalo-caudal planes is maintained, the
needle should enter the targeted calyx.
• It is preferable to use the 18-gauge rather
than a 21-gauge needle with the triangulation
technique, as its stiffness provides better
stability to help maintain angle of entry
25.
26.
27.
28. • The Standard Operative Technique of PCNL
consists of Four main steps:
• 1. Opacification
• 2. Percutaneous puncture of pelvi-calyceal
system.
• 3. Development of track.
• 4. Fragmentation and/or removal of stone.
29. 1. OPACIFICATION of PCS
• Air, contrast or both can be used.
• These agents can be gradually established in PCS
by antegrade or retrograde means.
RETROGRADE UROGRAPHY:
• Contrast injected directly into PCS via Catheter.
ANTEGRADE UROGRAPHY:
A FINE GUAGE NEEdle( Chiba) under local anesthetic inserted directly
into PCS and contrast injected to visualize the calyces, pelvis and
ureter.
32. • Initial exploratory puncture is performed with
a 21G or 22G skinny needle from below the
12th rib, targeting a posterior calyx.
• A second definitive puncture is then
performed with a larger 18G needle.
• Insertion of this needle into the target calyx
enables subsequent introduction of a .038 or
.035 working guidewire into the pelvi-calyceal
system.
2. PERCUTANEOUS PUNCTURE OF PCS
33. • A supracostal puncture provides upper pole
renal access that is needed when there is
substantial stone burden in the upper pole
calyces, or in horseshoe kidneys.
34. 3.Development of Track
• The second step is to dilate a track from the skin
through the renal parenchyma into the collecting
system, and to place a working sheath.
• Over the guidewire, fascial dilators are inserted to
serially dilate the track between the skin and the renal
calyx to enable subsequent instrumentation.
• There are 3 types of fascial dilators:
1. Amplatz teflon dilators,
2. Alken telescopic metal dilators,
3. balloon dilator.
35.
36. • Under fluoroscopic guidance, fascial dilators
are inserted along the extra-stiff guidewire
until their tips enter well into the collecting
system.
• The fastest method of track dilatation is to use
a balloon dilator, as it does not require serial
insertion of multiple dilators of increasing size.
Its only drawback is the cost of the balloon
dilator.
37. • After dilating the track to the desired size
(generally 26 to 30 Fr), an Amplatz sheath is
slipped over the dilator and manipulated into the
collecting system.
• This Amplatz sheath provides tamponade to stop
any bleeding from the freshly developed track,
while at the same time serves as a conduit for
introducing instruments and a channel for
irriggation fluid to flow out easily.
38. 4. Nephroscopy and Stone Extraction
The last step is to introduce a nephroscope via the
Amplatz sheath into the pelvi-calyceal system to
locate the stones (Fig 11).
39. • Smaller stones can be retrieved with rigid stone
forceps directly via the Amplatz sheath.
• Larger stones have to be fragmented first using
either one of the following energies:
1. Ultrasonic lithotripsy.
2. Holmium laser lithotripsy.
3. Pneumatic lithotripsy.
• Holmium laser is ideal for cutting harder stones
into smaller pieces.
40. Complications
Possible complications of PCNL include:
• Haemorrhage.
• Collecting System Injury
• Injury to adjacent bowel.
• Failed access or failure of equipment.
• Pneumothorax and Pleural effusion (with supracostal
punctures)
• Sepsis
Major complications can occur in 1% to 7% of patients
undergoing PCNL
41. COMPLICATIONS
Acute Hemorrhage
• The most common significant complication
• Factors associated with hemorrhage during
percutaneous surgery include:
• multiple access sites
• supracostal access
• increasing tract size
• tract dilation
• Prolonged operative time
• renal pelvic perforation
42. Delayed Hemorrhage
Delayed hemorrhage is usually due to
arteriovenous fistulas or arterial
pseudoaneurysms(more common)
The standard treatment of renal arteriovenous
fistulae and arterial pseudoaneurysms is
selective angio-embolization
Nephrectomy may be required if selective
angioembolization fails.
43. Postoperative Fever and Sepsis
• Incidence: 15% to 30%
• Risk factors for fever
infectious stones
preoperative urinary tract infection
Hydronephrosis
indwelling ureteral stent or
nephrostomy tube
• If pus is aspirated upon initial percutaneous to the
upper urinary tract, the safest measure is to abort the
procedure and leave a nephrostomy tube for drainage
44.
45. References
1. Fernstrom I, Johansson B. Percutaneous pyelolithotomy: a new extraction
technique. Scandinavian Journal of Urology and Nephrology, 10: 257, 1976.
2. Alken P, Hutschenreiter G, Gunther R, Marberger M. Percutaneous stone
manipulation. Journal of Urology, 125: 463- 466, 1981.
3. Wickham JEA, Kellett MJ. Percutaneous nephrolithotomy. British Journal of
Urology, 53: 297, 1981
4. Albala DM, et al. Lower pole 1: a prospective randomized trial of extracorporeal
shockwave lithotripsy and percutaneous nephrostolithotomy for lower pole
nephrolithiasis - initial results. Journal of Urology, 166: 2072, 2001.
5. Segura JW, et al. Nephrolithiasis clinical guidelines panel summary report on the
management of staghorn calculi. Journal of Urology, 151: 1648, 1994
49. To use the “triangulation” technique,
inspect the kidney with the fluoroscopy unit directly above the patient to select the
desired calyx, and hold the needle in the approximate position of the
desired angle of entry.
Rotate the top of the fluoroscopy unit cephalad
and lateral, and widen the field of view with the collimator such
that mediolateral (left-right) movements of the needle are apparent.
Move the shaft of the needle while keeping its tip in place until the
needle is aimed toward the desired calyx (Fig. 8-20A).
Then rotate the top of the fluoroscopy unit medially 45 degrees. While keeping
the mediolateral orientation of the needle constant, move the
needle in the cephalo-caudad (up-down) plane until the needle is
again aimed toward the desired calyx (Fig. 8-20B).
Resting the
forearm on the patient’s back will help stabilize the needle in one
plane while moving in the other. Move the fluoroscopy unit back
and forth between these two positions until the needle remains
aimed at the desired calyx on both views. Advance the needle under
fluoroscopic guidance while monitoring the anteroposterior direction
(depth) of the needle tip. If the needle position in the mediolateral
BRUSHITE: Calcium Phosphate stones….have tendency to reccurr.
The Panel emphasised that the first part of combination therapy should be percutaneous debulking, to remove largest stone burden possible starting from the part centrally located in renal pelvis. This is followed by adjuvant shock wave lithotripsy to the hopefully small residual peripheral burden in the calyces (Fig 3), and a 'second look' percutaneous procedure via the mature track to hasten clearance of post shock wave stone fragments, generally referred to as 'sandwich therapy' 6.
3. Gradual descent into the kidney
The standard 26 Fr rigid rod-lens nephroscope is used.
Continuous irrigation with warm normal saline is set up to fill the pelvi-calyceal system with fluid, with inflow via the endoscope and outflow simply via the Amplatz sheath.
This allows a very rapid flow to clear stone fragments and blood, and thus enables good endoscopic view.
It dissipates the heat energy of mechanical lithotripsy and so minimises its potential injury.
Last but not least, the importance of an effective irrigation system is to maintain a low pressure in the pelvi-calyceal system that reduces the risks of pyelo-renal reflux and its resultant fluid absorption and sepsis.