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Extracorporeal Shock-wave Lithotripsy
re-treatment rate found in the literature by the American Urological Figure 1: Distal Ureteral Stone Before and After
Association (AUA)/European Association of Urology (EAU) guideline
Extracorporeal Shock-wave Lithotripsy
panel on ureteral stones.
1,2
In this regard, it is of considerable
interest to note that as many as 76.3% of patients were sufficiently
treated with only one treatment session and that for distal ureteral
stones this figure was as high as 83.2%.
3
Typical examples of ESWL-
treated stones in the distal and proximal ureters are shown in
Figures 1 and 2.
Associated auxiliary procedures such as ureteral stenting,
manipulation with ureteral catheters and contrast medium were used
in approximately 19% of our patients. However, these procedures
2
were usually confined to those patients in whom the stones were
Stone size: 21x7mm (115mm ). Treated with one session of 2,012 shock waves
(Storz Modulith SLX-F2).
difficult to treat and who thus required repeated treatment sessions.
Auxiliary procedures are also necessary in URS-treated patients,
1,2
but
Figure 2: Proximal Ureteral Stone Before and After
the great advantage of ESWL is that all stone-removing steps can be
Extracorporeal Shock-wave Lithotripsy
accomplished without the need for general or regional anaesthesia.
4
It is of particular interest to note that the treatment results in the
recent report
3
were almost identical to those that we previously
reported with the Dornier HM3 lithotripter.
5
When the treatment
results, need for repeat ESWL, auxiliary procedures and anaesthesia
were considered for patients treated by the author with the Dornier
HM3, the Dornier/Philips MFL 5000 and the Modulith SLX lithotripters,
almost identical data were recorded.
4
The overall stone-free rates with ESWL reported in the AUA/EAU
guideline document were 63–98% for stones with a diameter up to
10mm and 21–98% for stones larger than 10mm.
1,2
In a review of
treatment results carried out in 2005 on data from 20,659 patients, the
average stone-free rate was 86.5%, compared with 84.5% recorded
after URS in 5,520 patients.
4
In a number of recent reports the stone-
free rates after ESWL for ureteral stones varied between 69 and
91%.
6–20
In those studies that compared the outcome between ESWL
and URS,
6,10,12,13,17,20
stone-free rates of 71–89 and 73–89%, respectively,
were recorded. In a review of 33 articles, 67% of patients became
stone-free after URS compared with 73% after ESWL,
13
thus there was 2
Stone size: 15x7mm (82mm ). Treated with one session of 1,200 shock waves (Storz Modulith
only a minor difference in favour of URS. A similar treatment result
SLX-F2). Duration of treatment: 17 minutes.
with the two treatment modalities was reported in a Norwegian study,
with three-month stone-free rates of 88 and 89%, respectively.
20
Stones in the Kidneys
Moreover, a matched-pair analysis from Scotland showed a better Approximately half of all patients who need active removal of urinary
stone-free rate with ESWL than with URS (89 versus 82%),
17
although tract stones have their stones in the kidneys. One or several stones at
the re-treatment rate was higher for ESWL-treated patients (23 versus any location in the kidney causing constant or intermittent pain,
11%). The treatment outcome with ESWL is determined by several haematuria or infection problems, or just posing a potential risk of an
factors, of which the type of lithotripter and the extent to which acute episode of ureteral colic or a threat to renal function, require
repeat sessions are offered are apparently the most important. In active removal. For these patients ESWL provides an excellent
addition, the selection of patients will influence the result and that alternative, and this procedure’s usefulness for stone removal has
information is only occasionally included in the publications. stood the test of time. Most stones in the kidney can be satisfactorily
disintegrated with ESWL. Disintegration is considered satisfactory
In the process of choosing between ESWL and URS for the removal of when the largest stone fragments have a diameter not exceeding
ureteral stones, it must be emphasised that the AUA/EAU guideline 4mm. This size limit should allow spontaneous passage of the stone
panel found both methods acceptable as first-time treatment material. For stones in the kidney, the absolute stone-free rates are
alternatives.
1,2
The great advantage of ESWL is that it is a non-invasive lower than those recorded for ureteral stones despite sufficient
or, in a fraction of patients, a very low-invasive form of treatment that disintegration. This problem is not directly related to the lithotripter
is easy to perform, has a very low risk of complications and can be technology, but rather to the anatomical and possibly physiological
carried out with limited preparation of the patient. It is my opinion that conditions in the renal collecting system.
the need for re-treatments discussed above is a reasonably low price
to pay for the other advantages. In ureteral stone treatment, residual In a review of recent treatment results of a mainly unselected group of
stones or fragments are not a problem unless stones are pushed up patients with stones in the kidney in my own department, only
to the kidney before ESWL, but in most centres this technique was excluding a few patients with staghorn stones composed of CaOx or
abandoned many years ago. cystine, 54.2% of the patients became completely stone-free as judged
EUROPEAN UROLOGICAL REVIEW 69