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Treatment Strategies of Ureteral Stones
Stefanos Papadoukakis a, Jens-Uwe Stolzenburg b, Michael C. Truss a,*
a
b
Department of Urology, Klinikum Dortmund, Dortmund, Germany
Department of Urology, University of Leipzig, Leipzig, Germany
Article info
Abstract
Keywords:
Urolithiasis
Ureteral stones
Ureteroscopy
Lithotripsy
Urinary stone disease is a major health care problem due to its high
prevalence and incidence. There are different therapeutic approaches
for ureteral stones depending on stone size, location and anatomical
variations of the urogenital tract. Watchful waiting with concomitant
medication (i.e., analgetics, anti-inflammatory agents, alpha-blockers) is
considered an option for smaller stones (<6 mm) that have a high
probability for spontaneous passage. Extracorporeal shock wave lithotripsy is a minimally invasive therapeutic approach which has been
widely used through the past 20 years. It is a standardized procedure
which results in stone free rates between 59% and 100% depending on
the size and the location of the stone as well as the type of the lithotriptor. However, more than one session are frequently needed and
ureteral stenting is still a matter of debate. Ureteroscopy results in stone
free rates of almost 95% in a single session. Stone removal may be
achieved with forceps and baskets and with or without intraureteral
stone disintegration with various lithotripsy devices. Treatment
approaches should be individualized in order to achieve optimum outcomes.
# 2006 European Association of Urology and European Board of Urology.
Published by Elsevier B.V. All rights reserved.
* Corresponding author. Department of Urology, Klinikum Dortmund gGmbH, Münsterstr.
240, D-44145 Dortmund. Tel. +49 231 953 18700; Fax: +49 231 953 18790.
E-mail address: [email protected] (M.C. Truss).
1.
Introduction, epidemiology and stone
composition
Urinary stones are the third most common affliction
of the urinary tract, exceeded only by urinary tract
infections and pathologic conditions of the prostate
(BPH and prostate cancer). Stone disease has been a
major problem afflicting human population ever
since the antiquity. Early reports of the disease can
be found in the Aphorisms of Hipparchos and even in
Hippocrates. The disease is both very common
among men and women with estimated prevalence
among the population of 2–3% and an estimated
lifetime risk of 12% for white males [1] and 5–6% for
white females [2]. The life time recurrence rate is
approximately 50% [3]. The interval between recurrences is variable, with approximately 10% within
one year, 35% within five years, and 50% within 10
years [2]. The increased incidence of urinary stones
in the industrialized world is associated with
improved standards of living (mainly including the
high dietary intake of proteins and minerals) as well
1871-2592/$ – see front matter # 2006 European Association of Urology and European Board of Urology.
Published by Elsevier B.V. All rights reserved.
doi:10.1016/j.eeus.2006.07.004
185
eau-ebu update series 4 (2006) 184–190
as with race, ethnicity and region of residence [4]. A
seasonal variation is also seen, with high urinary
calcium oxalate saturation in men during summer
and in women during early winter [5]. Stones form
twice as often in men as in women. The peak age in
men is 30 years; women have a bimodal age
distribution, with peaks at 35 and 55 years.
The composition of the urinary stones can vary
considerably (calcium oxalate, calcium phosphate,
uric acid, ammonium urate, sodium urate, magnesium ammonium phosphate, carbonate apatite,
cystine, xanthine, sulphonamide and indinavir
stones).
Many theories have been proposed for the pathogenesis of urolithiasis, including nucleation theory,
the crystal inhibitor theory or even the crystal
retention theory. Moreover there are a number of
diseases associated with stone formation (i.e., hyperparathyroidism, renal tubular acidosis, cystinuria,
hyperoxaluria, intestinal malabsorptive conditions)
as well as medications (i.e., calcium supplements,
vitamin D, triamterene, indinavir). Predisposing
factors for stone formation also include anatomical
abnormalities (i.e., ureteral strictures, vesico-ureteral
reflux, ureteropelvic stenosis, extrinsic ureteral
compression and ureterocele among others).
Most of the urinary stones pass through the renal
calyces to the pelvis and subsequently to the ureter.
Primary stone formation in the ureter requires an
already existing obstructed urinary flow. Despite an
improved understanding of the mechanisms of
stone formation it is obvious that ureteral stones
are still a problem afflicting an increasing number of
patients worldwide. Advances in technology have
led to a wide armamentarium for the treatment of
the urinary stones.
2.
Watchful waiting
The initial step of any adequate management of the
ureteral stones should be considered the relief of
pain. Pain relief may be achieved by the administration of various agents through different routes.
Diclofenac sodium, indomethacine, ibuprofen,
methamizol, tramadol, pentazocine and hydromorphone with atropine sulphate are among the most
frequently used agents. Comparative studies
between diclofenac and other agents proved diclofenac to be superior to narcotic analgetics [6]
(showing fewer side effects), while on the other
hand showed no difference compared to Ketoprofen
[7]. Moreover it has been speculated that diclofenac
may be able to prevent recurrent episodes of renal
colic if given on a regular basis (50 mg t.i.d) [8].
Table 1 – Stone size, location and spontaneous passage
rate [10,13]
Stone size, location
<4 mm
<7 mm proximal ureter
<7 mm mid ureter
<7 mm distal ureter
Stone passage rate
80%
25%
45%
70%
The treatment strategy of watchful waiting with
ultrasound follow-up is an appealing and efficacious
approach for ureteral stones with a diameter of
7 mm. Ureteral stones of less than 4 mm in
diameter have a chance of over 80% to pass
spontaneously [9].
On the contrary, most stones with a diameter
>8 mm will ultimately necessitate intervention. The
spontaneous passage rate depends on the stone
burden as well as its location. The overall passage
rate is 25% for the proximal ureter stones, 45% for
the mid ureter stones and 70% for the distal ureter
stones, provided that the mean diameter does not
exceed 7 mm (Table 1).
Time to spontaneous passage also depends on
stone size and location. In one study the mean
passage time was between 5 days (for smaller distal
stones) and 59 days (for larger proximal stones) [10].
Therefore conservative management within a
watchful waiting strategy of 4 to 6 weeks may be
reasonable for smaller distal stones if the patient
remains asymptomatic. However the presence of an
acute infection, the decreased renal function or the
persistence of the symptoms despite the analgesic
therapy could be among the contraindications for
such an approach (Table 2).
Recently a number of studies investigated the
effect of various drugs on spontaneous stone
expulsion of distal ureteral stones. These drugs
included analgetics, anti-inflammatory drugs, calcium antagonists such as nifedipine and alphablockers such as tamsulosin. Of the above mentioned agents tamsulosin seems to be especially
promising in preliminary studies [11].
Table 2 – Contraindications for watchful waiting
approach [13]
Containdications for watchful waiting approach of
ureteral stones
Stone diameter >7 mm
Inadequate pain relief
Concomitant infection
Risk of pyonephrosis or sepsis
Bilateral obstruction, or unilateral obstruction in single kidneys
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3.
Extracorporeal shock wave lithotripsy
(ESWL)
ESWL has been established as a major therapeutic
and minimally invasive option for the treatment of
renal stones the last twenty years. Initially, there
was uncertainty about the efficacy in the treatment
of ureteral stones. There were major concerns due
the mobility of ureteral stones, the possible affection
of organs outside the urinary tract as well as the
applied energy. With increased expertise it has been
shown that ESWL is safe and effective in the
treatment of ureteral stones.
Some early studies reported success and stone
free rate after ESWL in up to 90% [12]. It could have
been shown that ureteral stones may be treated with
ESWL without regional or general anaesthesia and
with low complication rate or side effects. The most
common side effects of ESWL are local pain, edema
of the ureteral mucosa with subsequent mild
obstruction and hydronephrosis.
The stone free rate is depending on the study, the
type of the lithotriptor used, the size of the stone and
its location within the ureter. It has been estimated
that a mean stone free rate of 77.4% (range 63–100) is
achievable for proximal ureter stones, with a
retreatment rate of 10%. Data for mid ureteral
stones are 80.3%(range 60–98) and 8.2% and for
distal ureteral stones 77.9 (range 59–100) and 9.4%,
respectively [13] (Table 3).
The rather wide range of the above mentioned
rates is attributed to the different types of equipment used in each study, the size and the composition of the stone as well as the degree of the
impaction and the prior shockwave sessions.
In a remarkable study from the United States,
18.825 patients were treated with one to three
sessions of ESWL for ureteral stones of variable
location and size. All patients were treated within a 6
year follow up period (1988–1993). The mean stone
free rate was 83.8% (ranging from 67.9% for stones
larger than 20 mm, to 85.8% for stones smaller than
10 mm). The retreatment rate was 10.8% [14].
In the majority of studies only a minor percentage
of patients required a previously inserted DJ stent.
The vast majority (>80%) was treated with ESWL in
Table 3 – Stone free rate and retreatment rate after ESWL
for ureteral stones
Stone location
Stone free rate
Retreatment rate
Proximal ureter
Mid ureter
Distal ureter
77.4% (63–100%)
80.3% (60–98%)
77.9% (59–100%)
10%
8.2%
9.4%
situ without a stent. Interestingly, complication and
retreatment rates were not affected by ureteral
stents [14].
The introduction of the 2nd generation lithotriptors that use electro hydraulic energy has improved
single session stone free rates. The technical
development of the latest 3rd generation lithotripters that use electromagnetic energy also led to a
reduction of retreatment rates, increased the stone
free rate up to 88.5% and reduced treatment time per
session to 54(32)min [16].
The fact that ESWL is a minimal invasive
procedure that may be applied without local,
regional or general anesthesia has made it an
attractive alternative in the treatment of ureteral
stones. However, stone free rates after a single
treatment session still remain still higher with
ureteroscopy.
4.
Ureteroscopy
What started as a therapeutic approach in selected
centres has become the standard therapeutic option
for the past decade. Ureteroscopy has changed our
perception and eventually our treatment strategies
of ureteral stones. Ureteroscopy was first described
from one of the pioneers in Urology, Hugh Hampton
Young back in 1912 [17], but it has not been until the
late 70’s that it became a standardized procedure
[18]. Alone in the USA the ureteroscopic procedures
have increased by 83% in the past 10 years [19].
The ureteroscopic approach has been standardized through the years [20]. The procedure is
performed under general or regional anaesthesia
in an operative room with fluoroscopic equipment
with the patient in the lithotomy position. Prior
stenting of the ureter remains a debatable issue. It is
not indicated on a routine basis, but only occasionally depending on the size and the shape of the
stone, the size of the ureteroscope and the diameter
of the ureter. The ultimate goal is the retrievement
of the stone, either as one piece (if <10 mm) or in
more pieces after its disintegration within the ureter.
Indications for an ureteroscopy can be any stone
within the ureter, irrespective distal or proximal. If
there is a suspicion of any other pathology beside
urolithiasis ureteroscopy is the only modality that
can actually establish a diagnosis.
The clinical outcome of ureteroscopy has been
improved considerably over the years. The stone
free rates used to be 72% and 90% for proximal and
distal ureteral calculi till 1996 [34]. The review of the
latest literature shows that the stone free rates with
the use of semi rigid or flexible ureteroscopes have
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Table 4 – Stone free rate after ureteroscopic extraction
Stone location
Stone free rate
Proximal ureter
Distal ureter
74%
90–100%
increased to 90–100% for the distal ureteral calculi
and to 74% for proximal ureteral stones [35] (Table 4).
Moreover an impressive 95% of the patients were
stone free after a single procedure [30].
The instruments that are used are either rigid
ureteroscopes (9.5–11 F), or semi rigid (6.0–8.5 F)
or even flexible ureteroscopes inserted through a
10–13 F sheath. Stone removal is easier with a
rigid or a semi rigid instrument, while stone
fragmentation with laser may be more feasible
with a flexible instrument. The expanded use of
flexible ureteroscopes has enabled us to reach
stones even within the renal pelvis and calices that
have been considered unreachable with rigid
ureteroscopes. The miniaturisation of the instruments allows easier access within the ureter without prior dilatation in more than 50% of the patients
and easier approach of the proximal ureter [24]. On
the other hand, if a stone is localized in the distal
ureter, a rigid ureteroscope should be used due to
the superior visualisation and therefore better
efficacy.
Through the working channel of a rigid instrument a variety of tools can be introduced in order to
remove the stone in total (if the size is adequate).
For smaller distal stones the grasper or the forceps
is better since it allows better control in manipulation within the ureter. The ureteroscopic removal
of the stone with a basket is a fast approach
with minimal morbidity [21]. This approach seems
more suitable for small distal ureteral stones and
many variable type of baskets (such as nitinol
tipples basket) have been developed through the
past few years to enable the urologist to remove the
stone with minimal or no trauma to the ureteral
mucosa and a maximum of intraluminar mobility
[22].
Stone disintegration through a rigid ureteroscope
can be achieved with in situ lithotripsy. The
spectrum of lithotripters includes ultrasonic lithotripsy, electro hydraulic lithotripsy, ballistic lithotripsy, pneumatic lithotripsy, and laser lithotripsy.
Good vision throughout the procedure is facilitated
with a flow control unit. Laser lithotripsy is a reliable
method of stone disintegration irrespective of the
stone composition and hardness. It is carried out
through all types of ureteroscopes [25]. The Holmium-YAG Laser 365 mm fibre is recommended and
used for the treatment of ureteral stones, while the
200 mm fibre is indicated only for intrarenal stones
[26]. The Neodymium YAG Laser is also used, with
less success, especially in harder stones (i.e., cystine
stones), but it remains a cost effective alternative
option [27].
The ballistic lithotriptors with probes of 2.4 F are
introduced through semi rigid ureterorenoscopes.
They are less expensive compared to laser fibres,
and provide a fragmentation rate of 90–96% [29].
They are mostly indicated for distal ureteral calculi,
because their use in the proximal ureter may lead to
stone migration into the renal pelvis and calyces.
Using laser lithotriptors the trauma to the urethelial
mucosa is usually less compared to the other
lithotripters [28].
Comparative studies of the two lithotripsy
sources have shown that the Holmium YAG laser
seems to give superior stone free rates (97% vs. 87%)
[30] (Table 5). For stones <15 mm a ballistic
lithotripsy can be regarded as a standard, because
of its better efficacy and shorter operative time,
while for stones >15 mm a laser lithotripsy should
be advised because of its minimal risk of uereteral
injury.
Post-ureteroscopy stenting has been a matter of
debate for the past decade without a final consensus [31]. It is accepted that a DJ stent after a
procedure eliminates the risk of hydronephrosis
due to mucosal edema. On the other hand ureteral
stenting itself is associated with some degreee of
morbidity, including stent encrustation, ureteral
mucosa erosion, flank pain and irritative voiding
symptoms. Recent comparative studies have
shown that procedural costs can be reduced by
30% if postoperative stenting is avoided [32,33].
Currently most urologists avoid stenting as long as
ureteroscopy was uncomplicated and no dilatation
was necessary.
Acute intraoperative complications of ureteroscopy have been reported with a rate of 9% and 11%
for distal and proximal stones, respectively [34],
including ureteral avulsion, intussusception, perforation, false passage, mucosal abrasion, extravasation, thermal injury, equipment malfunction,
and bleeding [36]. Postoperative complications
Table 5 – Stone free rate after various ureteroscopic
approaches
Ureteroscopic approach
Stone free rate
Extraction (grasper, basket)
Ballistic lithotripsy
Laser lithotripsy
75–95%
87%
97%
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are rather rare (1%) and include urinary retention
[15], ureteral strictures, vesicoureteral reflux, and
postoperative steinstrasse along with ureteral
obstruction [36]. Most of the intraoperative complications are handled with a prolonged postoperative
stenting of the ureter [37]. The only exception to this
approach is the avulsion of the ureter which
requires an immediate operative intervention (i.e.,
autologous transplantation or ureteral reconstruction with small bowel) [38].
Finally, miniaturization of instruments continues, as shown with the introduction of a 4.5 F
ureteroscope [23].
5.
ESWL vs. ureteroscopy
There is no real debate or rivalry between those two
methods. Both are accepted as the main therapeutic
approaches to ureteral stones. ESWL is a minimally
invasive method that requires no anesthesia and in
most cases no hospitalization of the patient. On the
other hand its success rate for distal ureteral calculi
is still somewhat less favorable compared to
ureteroscopy and in many cases one single session
might not be sufficient.
Ureteroscopy is an operative procedure with
specific indications, extremely high stone free rate
and minimal complication rate. Most of the comparative studies between the two methods are not
conclusive and sometimes ambiguous. While
some studies are in favor of ESWL [15], others
concluded that ureteroscopy is the preferable
approach [39–41].
6.
Alternative strategies
The major treatment strategies for the ureteral
stones are the three above mentioned. Nevertheless,
chemolysis may also be indicated especially for uric
acid stones.
One should never forget other ‘‘conventional’’
techniques, such as open or laparoscopic ureterolithotomy as these options may be indicated in rare
circumstances.
7.
Conclusion
Urinary stone disease is a major health problem that
concerns millions of patients worldwide, since it
affects 2–3% of the population with a high recurrence rate of almost 50%. The treatment strategies
have been altered throughout the years, with the
introduction of new technological modalities. The
current trends in approaching a ureteral stone
depend mostly on the stone size and location in
the ureter. A watchful waiting approach, with
concomitant medication (pain relief, tamsulosin)
is indicated for relative small (<7 mm) stones,
localized at the distal ureter. The stone fragmentation using extracorporeal lithotripsy shows good
results even in bigger stones, both in the proximal
and distal ureter, and remains a less invasive option.
The ureteroscopic approach with simultaneous
extraction or intraureteral stone fragmentation
using various lithotripsy devices is an efficacious
single session treatment. There are certain indications, limitations, advantages and disadvantages for
each of the above mentioned approaches. The final
therapeutic decision should be individualized in
every patient (regarding preferences, age, and
coexisting comorbidity factors).
References
[1] Menon M, Parulkar BC, Drash GW, et al. Urinary lithiasis:
etiology, diagnosis, diagnosis and management. In:
Walsh PC, editor. Campbell’s Urology. 7th edition, Philadelphia: Saunders; 1998. p. 2661–733.
[2] Wilkinson H. Clinical investigation and management of
patients with renal stones. Ann Clin Biochem 2001;38:
180–7.
[3] Bihl G, Meyers A. Recurrent renal stone disease—
advances in pathogenesis and clinical management. Lancet 2001;358:651–6.
[4] Stamatelou KK, Francis ME, Jones CA, Nyberg Jr LM,
Curhan GC. Time trends in reported prevalence of kidney
stones in the United States: 1976–1994. Kidney Int 2003;
63:1817–23.
[5] Parks JH, Barsky R, Coe FL. Gender differences in seasonal
variation of urine stone risk factors. J Urol 2003;170:
384–8.
[6] Lundstam SO, Leissner KH, Wahlander LA, Kral KG. Prostaglandin-synthetase inhibition of diclofenac sodium in
the treatment of renal colic: comparison with use of a
narcotic analgesic. Lancet 1982;1096–7.
[7] Walden M, Lahtinen J, Elvander E. Analgesic effect and
tolerance of ketoprofen and diclofenacc in acute ureteral
colic. Scand J Urol Nephrol 1993;27:323–5.
[8] Cohen E, Hafner R, Rotenberg Z, Garty M. Comparison of
ketorolac and diclofenac in treatment of renal colic. Eur J
Clin Pharmacol 1998;54:455–8.
[9] Ibrahim Al, Shelty SD, Awad RM, Patel KP. Prognostic
factors in the conservative treatment of ureteric stones.
Br J Urol 1991;67:358–61.
[10] Miller OF, Kane CJ. Time to stone passage for observed
ureteral calculi: a guide for patient education. J Urol
1999;162:688–91.
[11] Dellabella M, Milanese J, Muzzonigro G. Randomised trial
of the efficacy of Tamsulosin, Nifedipin and Phloroglyci-
eau-ebu update series 4 (2006) 184–190
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]
[26]
[27]
[28]
[29]
[30]
nol in medical expulsive therapy for distal ureteral calculi.
J Urol 2005;174:167–72.
Miller K, Bubeck JR, Hautmann R. Extracorporeal shockwave litthotripsy of distal ureteral calculi. Eur Urol
1986;12:305.
Tiselius HG, Ackermann D, Alken P, Buck C, Conort P,
Gallucci M. Guidelines on urolithiasis. Eur Urol
2001;40:362–71.
Mobley TB, Myers DA, Jenkins JM, Grine WB, Jordan WR.
Effects of stents on lithotripsy of ureteral calculi: treatment results with 18.125 calculi using the Lithostar
lithotripter. J Urol 1994;152:66–7.
Pearl M, Nadler R, Berkowski E, Chen C, Dunn M,
Figenshau S, et al. Prospective randomized trial comparing shockwave lithotripsy and ureteroscopy for management of distal ureteral calculi. J Urol 2001;1255–60.
Sheir K, Madbouly K, Elsobsky E. Prospective randomised
comparative study of the effectiveness and safety of
Electrohydraulic and Electromagnetic Extracorporeal
Shockwave Lithotriptors. J Urol 2003;170:389–92.
Young HH, McKay RW. Congenital valvular obstruction of
the prostatic urethra. Surg Gynecol Obstr 1929;48:509.
Lyon ES, Kyker JS, Schoenberg HW. Transurethral ureteroscopy in women: a ready addition to the urological armamentarium. J Urol 1978;119:35–6.
Markovich R, Altana J, Jacobson A, Smith A. Changing
practice patterns in the management of nephrolithiasis in
the USA: Analysis of Medicare data. J Endourol 2002;
16:A105.
Grasso M, Conlin M, Bagley D. Retrograde ureteropyeloscopic treatment of 2 cm or greater upper urinary tract
and minor staghorn calculi. J Urol 1998;160:346–51.
Harmon WJ, Sershon PD, Blute ML, Patterson DE, Segura
JW. Ureteroscopy: current practice and long term complications. J Urol 1997;157:28–32.
Honey JR. Assessment of a new tipples nitinol stone
basket and comparison with an existing flat wire basket.
J Endourol 1998;12:529–32.
Marbeger M. ‘‘Needle’’ Ureteroscopes–where are the margins of miniaturisation. J Endourol 1992;I-2:46.
Puppo P, Riccioti G, Bozzo W, Intoini C. Primary endoscopic treatment of ureterci calculi. A review of 378 cases.
Eur Urol 1999;36:48–52.
Tawfiek ER, Bagley DH. Management of upper urinary
tract calculi with ureteroscopic techniques. Urology
1999;53:25–32.
Gould DL. Holmium:YAG Laser and its use in the treatment of urolithiasis: our first 160 cases. J Endourol
1998;12:23–6.
Delvechio FC, Auge BK, Brizuela RM, Weizer AZ, Zong P,
Preminger GM. In vitro analysis of the stone fragmentation ability of the FREDDY laser. J Endourol 2003;17:177–9.
Scarpa RM, De Lisa A, PorruD, Usai E. Holmium YAG laser
ureterolithotripsy. Eur Urol 1999;35:233–8.
Tan PK, Tan SM, Consigliere D. Ureteroscopic lithoclast
lithotripsy: a cost effective option. J Endourol 1998;12:
341–4.
Teichman JM, Rao RD, Rogenes VJ, Harris JM. Ureteroscopic management of ureteral calculi: electrohydraulic
[31]
[32]
[33]
[34]
[35]
[36]
[37]
[38]
[39]
[40]
[41]
189
versus holmium:YAG laser lithotripsy. J Urol 1997;
158:1358–61.
Knudsen B, Beiko D, Denstedt J. Stenting after ureteroscopy: pros and cons. Uro Clin N Am 2004;31:173–80.
Netto N, Ikonomidis J, Zillo C. Routine ureteral stenting
after ureteroscopy for ureteral lithiasis:Is it really necessary? J Urol 2001;166:1252–4.
Denstedt J, Wollin T, Sofer M, Nott L, Weir M, Honey J. A
prospective randomized controlled trial comparing nonstented versus stented ureteroscopic lithotripsy. J Urol
2001;165:1419–22.
Segura JW, Preminger GM, Assimos DG, Dretler SP, Kahn
RI, Macluso JN. Ureteral stones clinical guidelines panel
summary report on the management of ureteral calculi. J
Urol 1997;158:1915–21.
Osti AH, Hofmockel G, Frohmüller H. Ureteroscopic
treatment of ureteral stones: only an auxiliary measure
of extracorporeal shockwavelithotripsy or a primary
therapeutic option? Urol Int 1997;59:177–81.
Johnson B, Pearl M. Complications of ureteroscopy. Urol
Clin North Am 2004;31:157–71.
Ferraro RF, Abraham VE, Cohen TD, Preminger GM. A new
generation of semirigid fiberoptic ureteroscopes. J
Endourol 1999;13:35–40.
Martin X, Ndoye A, Konan PG, Feitosa LC, Gelet A, Dawahra
M, et al. Hazards of lumbar ureteroscopy: a propos of 4
cases of avulsion of the ureter. Prog Urol 1998;8:358–62.
Peschel R, Janetschek G, Bartsch G. Extracorporeal shockwave lithotripsy versus ureteroscopy for distal ureteral
calculi: A Prospective randomized study. J Urol
1999;162:1909–12.
Turk T, Jenkins A. A comparison of ureteoscopy to in situ
extracorporeal schockwave lithotripsy for the treatment
of distal ureteral calculi. J Urol 1999;161:45–7.
Lotan Y, Gettman M, Roehrborn C, Cadeddu G, Pearle M.
Management of ureteral calculi: A cost comparison decision making analysis. J Urol 2002;167:1621–9.
CME questions
Please visit www.eu-acme.org/europeanurology
to answer these CME questions on-line. The CME
credits will then be attributed automatically.
1. Which of the following antiviral agents is considered a causative factor for upper urinary tract
lithiasis
A. Acyclovir
B. Gancyclovir
C. Indinavir
D. Oseltamivir
2. Stone disease recurrence rate is
A. 10% for the first 5 years
B. 30% for the first year
C. 30% life time risk
D. 50% for the first 10 years
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eau-ebu update series 4 (2006) 184–190
3. Which of the following agents, initially introduced
for the treatment of BPH/LUTS, has been shown to
facilitate ureteral stone passage in preliminary
studies.
A. Tamsulosin
B. Terazosin
C. Finasteride
D. Serenoa Repens
4. The 3rd generation lithotriptors use
A. Electro-hydraulic energy
B. Electromagnetic energy
C. Ultrasound wave energy
D. Laser energy
5. Stone free rates after single session ureteroscopy,
reaches
A. 95%
B. 100%
C. 72%
D. 80%
6. Which of the following lasers have been widely
used in the ureteroscopic disintegration of ureteral stones
A. Neodymium YAG laser
B. Erbium YAG laser
C. Holmium-yttrium laser
D. Thulium laser