Global Health Asia-Pacific September 2020 September 2020 | Page 37
2. Extracorporeal Shockwave lithotripsy (ESWL)
ESWL is a popular treatment for stones <2cm in size
in the kidneys and upper ureter. It is performed as an
outpatient procedure, and involves the patient lying
on a specially constructed treatment platform. Shock
waves of varying intensities are created outside the
body and transmitted through the skin and body tissues
to converge on these stones. The stones are then
shattered into smaller particles that pass easily through
the urinary tract in the urine (figure 2). �ecovery time is
relatively short, and most people can resume normal
activities in a few days. Side effects of �SW� treatment
include bruising and pain around the treated kidney;
downstream blockage of stone fragments in the lower
ureter; and incomplete stone clearance requiring multiple
treatment sessions.
Figure 3.
(a) A flexible ureterorenoscope is used to access stones in the
urinary tract.
(b) Holmium laser and basket used to eradicate stones.
4. Percutaneous Nephrolithotomy (PCNL)
For kidney stones > 2cm in size or occupying a
significant part of the kidney (known as staghorn stones),
�C�� is the treatment of choice for definitive stone
clearance. This procedure is performed under general
anaesthesia, usually with the patient lying prone on the
surgical table. Under X-ray or ultrasound guidance, the
urologist makes a tiny incision in the back and creates a
tunnel directly into the relevant chamber of the kidney.
�igid and �exible nephroscopes are used to locate to
the stones, which are then shattered and removed using
various devices (figure 4). A small nephrostomy tube
is left in the kidney for a few days till residual bleeding
clears up.
Figure 2. Extracorporeal shockwave lithotripter for kidney stones.
3. Ureterorenoscopy (URS)
For stones in the lower ureter <2cm, specially
constructed small-calibre endoscopes are passed up
the ureter to the stone’s location with the aid of guidewires
under X-ray guidance. The stones may then be
shattered using a Holmium laser probe under direct
vision, and the fragments retrieved out of the ureter using
special stone baskets. If the ureter or kidney is swollen
from stone obstruction, a temporary plastic stent is left
in the ureter to facilitate healing, and is subsequently
removed using a cystoscope 4-6 weeks after the initial
procedure. U�S is usually performed as an outpatient
procedure under general anaesthesia. �ain after U�S
usually resolves after 2-3 days, although blood in the
urine will take slightly longer to clear up.
In recent years, advances in endoscope technology
have enabled urologists to use small-calibre �exible
ureterorenoscopes to steer all the way up the upper
ureter into the kidney, and remove kidney stones using
Holmium lasers and stone baskets (figure �). This has
proved most successful for definitive clearance of stones
located in the lower chambers of the kidney, for which
ESWL has poor stone clearance rates.
Figure 4. Use of rigid and flexible nephroscopes to access stones in
the kidney through a small incision in the skin.
Which treatment is best for me?
Urinary stones are a common cause of visits to the
emergency department. Patients are usually referred
on to the urologist, who will then advise on the most
appropriate treatment approach based on the stone’s
size, characteristics of the urinary tract anatomy, and
clinical condition. Advances in medical therapy and
surgical technologies now allow stones to be eradicated
successfully with minimal scars, less pain and swift
recovery.
Dr.Gerald Tan Yau
Min is a consultant
urologist at Advanced
Urology with over
23 years of clinical
experience with a
record of 1,500 robotic
radical prostatectomies
performed. He
is internationally
renowned for his
expertise in minimally
invasive and robotic
surgery for prostate,
kidney and bladder
diseases. He may be
contacted via email
at enquiry@urology.
com.sg.
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