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995
Stones and Infection Caliceal Diverticula: Percutaneous
in Renal Treatment
with
Procedures -1
..
James Stephanie
H. Ellis1
K. Patterson1 L. Paul Sonda2
Joel F. PIatt1 E. Sheffner1
Steven Edward
J. Woolsey1’3
Percutaneous
treatment
of symptomatic
caliceal
diverticula
has expanded
the appli-
cation of uroradiologic intervention. To assess the safety and efficacy of these procedures, we have reviewed our experience with percutaneous management of 12 symptomatic caliceal diverticula, 10 with stones and two infected. Nine stone-bearing diverticula were punctured directly with subsequent tract dilatation, nephroscopic stone extraction, and cavity obliteration (six with fulguration and drainage and three with drainage alOne). One case was approached indirectly by puncturing a distant calix, dilating the diverticular neck, and flushing the stones into the collecting system for extraction. This cavity was not treated. Two infected diverticula were punctured directly for drainage and obliteration (one by fulguration and one by tetracycline sclerosis). Complete stone extractions were accomplished in all 10 cases. In eight with clinical follow-up ranging from 4 months to 6 years, one stone has recurred and seven patients are asymptomatic. Follow-up urograms were available in eight of 10 patients in whom cavity obliteration was attempted; in six (75%) of eight, nonvisualization of the diverticulum indicated successful obliteration. Only one major complication (unnoma requiring drainage) occurred. We conclude that percutaneous procedures are safe and effective in treating infected or stone-bearing caliceal diverticula. Direct diverticular puncture for access and diverticular fulguration for cavity obliteration is our preferred technique. AJR
156:995-1000, May 1991
Caliceal diverticula are found on 0.21 to 0.45% of excretory urograms [1 2]. The true prevalence is most likely greater, because some diverticula are visualized only by retrograde pyelography [2]. Most caliceal diverticula are asymptomatic. Symptoms occur when there is urinary stasis leading to infection and calculi. Until recently, the treatment of symptomatic caliceal diverticula has been surgical. However, newer techniques for percutaneous access to the kidney and extraction of stones can be applied to the treatment of infected or stone-bearing caliceal diverticula [3-7]. We report our experience in percutaneous treatment in 12 patients with symptomatic caliceal diverticula. ,
Received September 1 1 , 1 990; revision November 20, 1990.
accepted
after
Presented in part at the annual meeting of the American Roentgen Ray Society, Washington, DC, May 1990. I Department of Radiology (Bi D520), University Hospital,
University
of Michigan
Medical
Center,
University
Address
reprint
of Surgery,
of Michigan
Medical
of Urology, Ann Arbor,
in two,
requests
Section Center,
and Methods
Twelve patients (three men, were referred to our institution caliceal diverticula. Histories at patients, flank pain in two, both
Box 0030, 1500 E. Medical Center Dr., Ann Arbor, MI 481 09-0030. Ellis. 2 Department
Subjects Subjects
to J. H.
and
mild
flank
pain
and
nine women), ranging from 24 to 64 (mean, 40.5) years old, for treatment of stone-bearing or non-stone-bearing infected presentation included recurrent urinary tract infections in two urinary tract infection and flank pain in five, gross hematuria occasional
abscess surgically drained, apparently
MI 48109. address:
Radiology
Ltd.,
85716.
Tucson,
AZ
had pyelolithotomies diverticula contained
0361-803X/91/1565-0995
extracorporeal
© American Roentgen Ray Society
isfactory
passage
hematuria
in another.
Two
patients
arising within the caliceal diverticula.
had
had
a renal
Four patients had
of the ipsilateral kidney at other institutions, but it is not known if the stone at the time of the previous procedures. Two patients had had
shock-wave of fragments.
lithotripsy
(ESWL) of their stone-bearing
diverticula
without
sat-
996
ELLIS
ET AL.
Fig. 1.-A,
AJR:156,
May 1991
cluster
of 25 small
Plain film shows
stones.
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B, Retrograde pyelogram shows that stones are contained in a caliceal diverticulum arising from upper pole of left kidney.
A
B
Preprocedure
injection of methylene
Studies
via the
Each
patient
immediately
had a retrograde
before
the
or antegrade
procedure
pyelogram
to evaluate
renal
anatomy.
obtained Ten
of
the 12 diverticula the right kidney.
were found in the left kidney, and two occurred in Eight were located in the upper pole, three in the midpole, and one in the lower pole. Others have also noted that upper
calices
are the most frequent sites of both diverticula and [1 , 2]. More than half of our diverticula arose from posterior calices. All were Type I diverticula (arising from a minor calix) by the criteria of Wulfsohn [8]. The diverticula ranged in size from 8 by 10 mm to 25 by 48 mm. Stones were present in 10 diverticula and ranged in size from 2 to pole
diverticular
27 mm.
stones
Four
diverticula contained single stones; the rest had as (Fig. 1). One patient had an incidental ipsilateral diverticulum, which did not contain stone and was not treated.
as 25 stones
many
second
indirect
who
had
with
analgesia (meperidine, Eleven ulum.
patients
In two
system with
a drainage
punctures
at another catheter
already
were administered.
into the caliceal
approach
One patient
had had an indirect
performed
or diazepam)
direct
an intercostal
12th ribs was required. diverticulum
midazolam,
received
patients,
under fluoroscopic guidance after consent. Local anesthesia and IV
between
with an upper
puncture
hospital in the
into
the
divertic11th
and
pole stone-bearing
the lower
pole
collecting
and was sent to our institution renal
a flexible
either
1 2-French
with
manual
dilators
or
30-French
with
a balloon
catheter.
Access to the neck of the diverticula in the 1 1 directly punctured cases was attempted on entry and was successful in three cases, leading to placement of safety wires. One of these cases was the infected diverticulum in which the access tract was dilated to only 1 2-French and no nephroscopy was performed. In the eight remaining
cases, the safety wire was coiled in the diverticula neck was applicable,
sought stone
neck in the patient
catheterized
by using
treated
fluoroscopy.
had
nephroscope
the
upper
pole
was
in the
reverse
and
basket.
forceps
out
approach
had
At our center,
one
pelvic
attempts
were
stone
to enter
unsuccessful
of the
upper
diverticulum
pole
The
both
nine
cases
suctioned
in which
before
access
catheter
in either cases)
indirectly
to
the
(Fig.
approached
case
neck,
necks
to was
ranging
on whether left
via
attached
catheters
we
flushed
infused
diverticular
Depending
diverticular
the diverticulum 3) for drainage
the
the
retrieved
were
agent
balloon
after
when
were
stones
contrast
to
with
and
pelvis and
out with a catheter
access
at
balloon catheter. three stones fell
renal
seven
with
obtained, the necks were dilated size from 18-French to 30-French. achieved
the
position
remaining
diverticulum
catheter (Fig. 2) and then a syringe. In the
into
Trendelenburg
extracted
the diverticulum
of the diverticular neck with an 18-French at the time of the second nephroscopy,
of
(eight
pelvis.
The nine nephrostomy tracts placed directly into stone-bearing diverticula were dilated with balloon catheters ranging in size from 24-French to 30-French. The indirect access tract was dilated to 26French. The tracts into the two infected diverticula were dilated to
indirect
institution.
dilatation However,
with
performed informed
the
the other
patient
All procedures were the patient had given
was
Methods used for stone extraction were rigid nephroscopy with forceps and ultrasonic lithotripsy, flexible nephroscopy with baskets, and simple suction with catheters. Of the 10 patients with stonebearing diverticula, complete extraction was accomplished in a single sitting at the time of the original puncture in six. One patient who underwent ESWL after an initial nephrostomy into the diverticulum for drainage had all of his fragments removed at a single subsequent nephroscopy. One patient required two nephroscopic procedures to remove stone, and one patient required three procedures. The patient
out Procedures
blue. The diverticular
approach
a large
Malecot
(three cases) or the renal pelvis and cavity obliteration in all but the
in which
no attempt
was
made
to oblit-
erate the diverticulum. After allowing the tract to mature for 2-4 days, we attempted diverticular obliteration with Bugby electrodes endoscopically in six of the 1 0 stone-bearing and one of the infected diverticula.
which which
After
fulguration,
drainage
catheters
were
not
replaced,
allowed drainage
the cavity and tract to close, except in one case in was continued with an 8-French nephrostomy tube for 2 days before tube removal. Tetracycline for sclerosis was infused twice in aliquots of 7 ml each, separated by 9 days, into the other infected
diverticulum.
the diverticulum
This
volume
was
chosen
to fill but
and was left in place for 5 mm before
not
distend
aspiration.
and the diverticular
via nephroscopy after tract dilatation and, where extraction. In five of these patients, nephroscopy was successful in directing a guidewire through the diverticular neck under direct visualization, aided in some cases by the retrograde
in
or not we
Follow-up In eight kidney
was
patients, available
clinical
and
(range,
4 months
radiologic
follow-up
to 6 years;
of the
mean,
involved
1 6 months).
AJR:156.
RENAL
May 1991
CALICEAL
DIVERTICULA
997
Fig. 2.-Lateral pyelogram of case with mdirect approach. Cluster of stones (white arrow) surrounded by contrast material is identified within diverticulum. Angled catheter (white arrowhead) has been manipulated into diverticulum for flushing of stones from cavity via contrast
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injection.
Note angulation
required
to enter di-
verticulum, making nephroscopy impossible. Ureteral catheter (black arrow) and safety oatheter containing guidewire (black arrowhead) are present. Fig. 3.-Pyelogram shows stenting of caliceal diverticulum with 24-French Malecot catheter after stone extraction and dilatation of diverticular neck. Wings of Malecot positioned within renal pelvis. 8-French extension lies within ureter
as protection
against loss of access if tube is
partly withdrawn inadvertentiy. Diverticulum is not opacified because it is filled by stent, but approximate location along course of tube is marked (D).
Fig.
4.-Caliceal
diverticulum
containing
stone and transitional cell carcinoma. A, Plain film shows stone material in right kidney (within diverticulum). B, Retrograde pyelogram shows soft-tissue
mass
representing
within
opacified
Two
patients
were
roureterectomy yet
reached
transitional
cell carcinoma
diverticulum.
for the
lost
to follow-up,
transitional
4-month
follow-up
cell
and
one
carcinoma.
had One
an interval patient
nephhas
period.
Results Stone
Infected
Diverticula
not
In the infected diverticula, cultures of aspirated showed no growth in one patient and minimal Proteus organisms in the other. Both patients treated with antibiotics before the procedures.
contents growth of had been
Extraction
Complete stone extractions were accomplished in all i 0 stone cases. One of the patients was found at the time of stone extraction to have a well-differentiated transitional cell carcinoma in the diverticulum in addition to the stone (Fig. 4). The mass had been visualized as a filling defect on a previous retrograde pyelogram and had increased in size on the retrograde pyelogram performed immediately before puncture. However, this enlargement was attributed to thrombus in this patient, who had presented with gross hematuria. The stone was removed via nephroscopy and excisional biopsy of the mass was performed. The patient subsequently elected to have a nephroureterectomy with excision of the drainage tract because of the possibility of tract seeding. Most stones were found to be mixtures of calcium oxalate monohydrate and hydroxyapatite. None of the stones were composed of cystine or uric acid.
Complications Minor complications included hemorrhage during the initial effort in three patients. This obscured the nephroscopic field and led to performance of the procedure in two stages. No transfusions were required. One of the patients who underwent an intercostal puncture developed a pneumothorax but did not require chest tube placement. One patient experienced transient hypertension and tachycardia during the procedure. One patient had mild extravasation of irrigant from the diverticulum; she experienced pain with fulguration, which obligated a second sitting to complete. Our only major complication was a urinoma from perforation of the renal pelvis with resultant pain and fever, which lengthened the patient’s hospital stay. The problem resolved with IV antibiotics and catheter drainage of the urinoma.
ELLIS
998
ET AL.
AJR:156,
Fig. 5.-Successful
verticulum A,
obliteration
by percutaneous
Preprocedure
May 1991
of caliceal
di-
techniques.
excretory
urogram
shows
lobulated caliceal diverticulum (arrows). Stone material is obscured by contrast material. Over-
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lying parenchymal thickness is reduced (arrowhead), typical for diverticula. B, Follow-up tomogram during excretory urog-
raphy at 13 months shows nonvisualization diverticulum. Focal loss of overlying chyma (arrowhead) again is seen.
Follow-up In six
patients
in whom
cavity
obliteration
was
attempted
by fulguration and in whom follow-up is available, nonvisualization of the diverticulum on careful follow-up excretory urography indicated successful obliteration (Fig. 5); this nonvisualization represented a change from preprocedural excretory urograms, which had shown the diverticula. One of these patients is asymptomatic but takes prophylactic antibiotics to prevent recurrent urinary tract infections; the others are entirely free of symptoms. One patient who underwent only catheter drainage of her diverticulum has had recurrence of her flank pain. Excretory urography 30 months after the procedure showed a persistent cavity in which stone has recurred. In the patient who underwent tetracycline sclerosis, the cavity persists on follow-up studies but the patient has remained asymptomatic. The patient who was found to have transitional cell carcinoma has been free of any evidence of tumor recurrence.
Discussion We were able to treat successfully 1 2 symptomatic caliceal diverticula, 1 0 of which contained stones, with percutaneous techniques. In those patients in whom fulguration with a Bugby electrode was performed and follow-up is available, no stones have recurred and the diverticula are no longer seen on excretory urography. Two diverticula are known to persist: one infected diverticulum in which tetracycline was used as the sclerosing agent, and one stone-bearing diverticulum in which tube drainage only was used. In the latter case, stone has recurred 30 months after the procedure. Although we were successful in extracting stones in a patient whose caliceal diverticulum had been approached indirectly
elsewhere,
ture the involved
we prefer,
diverticulum
as do others directly.
[3, 6], to punc-
The two major
advan-
of
renal paren-
tages of direct puncture are the ability to use the rigid nephroscope and the ability to treat the diverticular abnormality without accessing the diverticular neck, should this prove to be difficult. The ability to use rigid nephroscopy is a distinct advantage of the direct-puncture
approach.
The
better
optics
and
larger
irrigation channel of the rigid instrument are unquestionably beneficial in one-stage procedures for immediate visualization of the renal anatomy and stone if present, particularly in the presence of the bleeding that accompanies puncture and tract dilatation. Irrigation flow is much less through the smaller channels of the flexible nephroscope, and flow is further reduced when one channel is occupied with an instrument [9]. The rigid scope admits larger extraction instruments, and the ultrasonic lithotripsy available with the rigid scope is much more efficient in stone disintegration than the electrohydraulic lithotripsy of the flexible scope, especially for larger stones. Several other difficulties with the flexible nephroscope have been described [9]. For stone extraction or cavity fulguration with the indirect approach, the neck of the diverticulum must be located and the scope passed through it, a task that may be difficult or impossible, as we discovered in our indirectly approached
case, even with balloon dilatation This
difficulty
is avoided
of the diverticular
when
the
direct
neck (Fig.
is chosen. Ideally, with a direct diverticular puncture, the original guidewire and safety guidewire are inserted through the diverticular neck into the renal collecting system as a precaution against loss of access [3]. However, when access to the neck is not possible before tract dilatation, both wires can be coiled within the diverticulum. Lang and Glorioso [6] reported the successful use of a single guidewire in diverticular stone extractions when access to the neck was not obtained before dilatation. We have found it easy to place the second guidewire within the diverticulum and value the security it provides. 2).
approach
AJR:156.
In our
series,
large-caliber fulgurating obliterating
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single
RENAL
May 1991
diVerticular
approach fulguration,
the lining by stenting with a tube followed a few days later by electrode proved to be successful in
traumatizing
nephrostomy with the
case.
a Bugby cavity, whereas
In contrast,
stenting
alone
was
not
in a
Hulbert
et al. [3] reported successful obliteration in five stone cases using a direct and nephrostomy drainage for 2 weeks, without believing that the trauma of dilatation and ensuing
formation of granulation to obliterate the cavity. fulguration it was
CALICEAL
tissue around the tube The same group reported
to obliterate
thought
that
by the percutaneous diverticulum
might
parenchyma
[4].
a large
only
part
caliceal
diverticulum
of the lining
access
Obliteration
by the
firm,
of an infected
because
be traumatized
might
and because
be retarded
is sufficient the use of
shrinkage
of the
supporting
renal
diverticulum
has
been successfully accomplished with percutaneous drainage and stenting in one case [5], but was unsuccessfully attempted with percutaneously injected absolute alcohol in an infected
diverticulum
with
without
fulguration [3].
proaches cavity
obliteration
an occluded
have
neck
not
[7].
been
Indirect
ap-
successful
in
Unfortunately, no single center has enough cases for a wellcontrolled study comparing various modifications of percutaneous treatment of caliceal diverticula. Currently, we briefly attempt to access the neck ofthe diverticulum fluoroscopically upon entry, but it is often easier to place a wire across the neck nephroscopically after stone removal, aided by retrograde injection of methylene blue. After balloon dilatation of the diverticular neck, the neck is stented with a 24-French Malecot catheter. After the tract matures, typically in 48 hr, we proceed to fulguration of the diverticulum and its neck. If no problems occur, we remove all tubes immediately after fulguration, but occasionally tube in place for access
cavity shrinkage. We recommend cause we believe epithelium
within
we have
and/or
fulguration something the
rather should
diverticular
left a small
tube
nephrostomy
injections
to assess
than stenting alone bebe done directly to the
cavity
to incite
scar
forma-
tion. Stenting alone might only scarify the diverticular neck. The natural history of a diverticulum whose neck is isolated from
the collecting
system
is unknown;
theoretically
the resid-
ual cavity could become infected. A randomized study would be needed to compare the efficacy of fulguration vs stenting alone. However, fulguration under direct vision is easily controlled and adds no morbidity and very little time to the procedure.
Furthermore,
we
usually
remove
all tubes
after
and the patient can be discharged tube-free. In contrast, we discontinued our attempts at sclerosis with tetracycline after a single case because of the technical difficulties in calculating dosage and the potential hazards of fulguration
extravasation
tern. We believe fluoroscopic
before
or entry
that
careful
contrast
fulguration.
of tetracycline
into
inspection
injection
One should
with
the
with spot
collecting
sys-
nephroscopy
films
should
look for a flattened
and be done
renal papilla
and observe the anatomy of the neck. It is reasonable to fulgurate caliceal diverticula, as they are lined with nonsecretory endothelium [8]. However, should the presumed caliceal diverticulum
be in fact
a hydrocalix,
fulguration
of the
tract
DIVERTICULA
999
and portions of the cavity could lead to obstruction of the draining collecting ducts. The result could be focal renal parenchymal loss or redevelopment of the cavity and infection leading to abscess formation. We have percutaneously extracted stone from a patient not included in this series who appeared to have a caliceal diverticulum on initial retrograde pyelogram,
but which
looked
like a calix
on nephrostomy
tube
injection. A limitation of our study is that radiologic follow-up was limited to excretory urography. We are satisfied that, in those patients with follow-up urograms, at least the necks were obliterated because the diverticula had been identified on preprocedural excretory urography, and we feel that retrograde pyelography would not be useful. CT or sonography would be necessary to assess any residual cavity within the parenchyma, but this information is not available in our series or that of Hulbert et al. [3]. ESWL has replaced percutaneous nephrolithotomy in at least 90% of patients with nondiverticular renal calculi [10], but it has not been widely used in the treatment of diverticular calculi because the stone fragments may not pass through the narrow diverticular neck [1 i ]. Psihramis and Dretler [i2] have recently reported their experience with ESWL for treating 1 0 patients with diverticular calculi. Although all stones were completely fragmented in one or two treatments, only two patients had passed all stone fragments after a minimum follow-up period of 3 months. Three patients (30%) had persistent symptoms. Although we have successfully treated one diverticular stone with ESWL alone despite a narrow neck, two other diverticula (included in this series) treated with ESWL were referred for percutaneous stone extraction because of the inability of fragments to drain. Although primary use of ESWL for diverticular calculi has been proposed both for its low morbidity and the possibility of applying it in centers without extensive experience in percutaneous techniques [12], we believe that primary percutaneous nephrolithotomy is the optimal approach unless specific contraindications supervene. Percutaneous techniques have the advantage of treatment of the diverticulum at the same time as removal of the stone. Elimination of the underlying abnormality will reduce the chance of recurrent stones or infection. We have had no recurrences of stone in any patient who had successful cavity obliteration, but stone did recur in one of the two cases in which the cavity was not obliterated. Furthermore, some complications of ESWL are best treated with percutaneous techniques, so that it may be unwise to use ESWL for complex cases in which percutaneous techniques are not readily available. Two of our patients required percutaneous diverticular stone extraction when fragments failed to pass after ESWL. ESWL may be appropriate initial therapy in cases in which a percutaneous approach would be difficult. For example, a disadvantageous position such as a diverticular location centrally near the renal vessels or high under the ribs increases the
risks
of
hemorrhage
or
pneumothorax.
Percutaneous
techniques can be used later if ESWL fails. The most important factor that would lead us away from percutaneous treatment is the size of the diverticulum. Smaller diverticula are more difficult to puncture and to coil wires within. We suc-
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i 000
ELLIS
cessfully treated a diverticulum measuring 8 by 1 0 mm and believe that in experienced hands, favorably positioned diverticula as small as 6 or 7 mm might be treated. If wires cannot be coiled in the diverticulum or advanced through its neck, then the technique described by Glanz et al. [1 3] for difficult caliceal stones could be attempted. This involves puncturing the far wall of the cavity and anchoring guidewires in the adjacent renal parenchyma.
We conclude that percutaneous nephrostomy and nephroscopy provide a safe alternative to an open procedure for the treatment of infected or stone-bearing diverticula. Whenever possible, obliteration of the cavity should be attempted to reduce the chance of recurrence of symptoms.
ET
AL.
1 . Middleton AW Jr. Pfister RC. Stone-containing pyelocaliceal diverticulum: embryogenic, anatomic, radiologic and clinical characteristics. J Urol 1974;1 11:2-6 2. TimmonsJW Jr. Malek RS, Hattery RR, DeWeerd JH. Calicealdiverticulum. J Urol 1975:114:6-9 3. Hulbert JC, Reddy PK, Hunter DW, Castaheda-ZCiniga W, Amplatz K,
May 1991
Lange PH. Percutaneous techniques for the management of caliceal diverticula containing calculi. J Urol i986;135:225-227 4. Hulbert JC. LaPointe S, Reddy PK, Hunter DW, Castaheda-Zu#{241}iga W. Percutaneous endoscopic fulguration of a large volume caliceal diverticulum. J Urol 1987;138: 116-117 5. Kremers PW, Beckmann CF. Bihrle W, III. Percutaneous balloon dilatation in treatment of infected pyelocaliceal diverticulum. Urology i988;32: 29-32
6. Lang EK, Glorioso LW. Multiple percutaneous
access routes to multiple
calculi, calculi in caliceal diverticula, and staghom calculi. Radiology i986;158:21 1-214 7. Ramchandani P. Soulen RL, Kendall AR, Davis JA. Percutaneous management of a pyelocaliceal diverticular abscess. J Urol 1985;133:81-83 8. Wulfsohn MA. Pyelocaliceal diverticula. J Urol 1980;1 23: 1-8
9. Lange PH, Reddy PK, Hulbert JC, et al. Percutaneous
10.
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and other inaccessible” stones: instruments and techniques. J Urol i984;132:439-442 Bush WH, Gibbons RP, Lewis GP, Brannen GE. Impact of extracorporeal shock wave lithotripsy on percutaneous stone procedures. AJR
i986;147:89-93 1 1 . Smith TP, Castaneda-Z#{252}niga WR, Darcy MD, Amplatz K. Current trends in the management Radiol 1988:29: 145-1 50
12. Psihramis KE, Dretler SP. Extracorporeal diverticula
calculi.
J Urol i987;1
Cragg AH, Hunter of urinary stones.
DW, Acta
shock wave lithotripsy of caliceal
38:707-711
13. Glanz 5, Laungani GB, Gordon DH, Macchia RJ, Sclafani JA. Percutaneous removal
of renal
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caliceal
calculi:
an alternative
approach.
Urol
Radiol
995
Stones and Infection Caliceal Diverticula: Percutaneous
in Renal Treatment
with
Procedures -1
..
James Stephanie
H. Ellis1
K. Patterson1 L. Paul Sonda2
Joel F. PIatt1 E. Sheffner1
Steven Edward
J. Woolsey1’3
Percutaneous
treatment
of symptomatic
caliceal
diverticula
has expanded
the appli-
cation of uroradiologic intervention. To assess the safety and efficacy of these procedures, we have reviewed our experience with percutaneous management of 12 symptomatic caliceal diverticula, 10 with stones and two infected. Nine stone-bearing diverticula were punctured directly with subsequent tract dilatation, nephroscopic stone extraction, and cavity obliteration (six with fulguration and drainage and three with drainage alOne). One case was approached indirectly by puncturing a distant calix, dilating the diverticular neck, and flushing the stones into the collecting system for extraction. This cavity was not treated. Two infected diverticula were punctured directly for drainage and obliteration (one by fulguration and one by tetracycline sclerosis). Complete stone extractions were accomplished in all 10 cases. In eight with clinical follow-up ranging from 4 months to 6 years, one stone has recurred and seven patients are asymptomatic. Follow-up urograms were available in eight of 10 patients in whom cavity obliteration was attempted; in six (75%) of eight, nonvisualization of the diverticulum indicated successful obliteration. Only one major complication (unnoma requiring drainage) occurred. We conclude that percutaneous procedures are safe and effective in treating infected or stone-bearing caliceal diverticula. Direct diverticular puncture for access and diverticular fulguration for cavity obliteration is our preferred technique. AJR
156:995-1000, May 1991
Caliceal diverticula are found on 0.21 to 0.45% of excretory urograms [1 2]. The true prevalence is most likely greater, because some diverticula are visualized only by retrograde pyelography [2]. Most caliceal diverticula are asymptomatic. Symptoms occur when there is urinary stasis leading to infection and calculi. Until recently, the treatment of symptomatic caliceal diverticula has been surgical. However, newer techniques for percutaneous access to the kidney and extraction of stones can be applied to the treatment of infected or stone-bearing caliceal diverticula [3-7]. We report our experience in percutaneous treatment in 12 patients with symptomatic caliceal diverticula. ,
Received September 1 1 , 1 990; revision November 20, 1990.
accepted
after
Presented in part at the annual meeting of the American Roentgen Ray Society, Washington, DC, May 1990. I Department of Radiology (Bi D520), University Hospital,
University
of Michigan
Medical
Center,
University
Address
reprint
of Surgery,
of Michigan
Medical
of Urology, Ann Arbor,
in two,
requests
Section Center,
and Methods
Twelve patients (three men, were referred to our institution caliceal diverticula. Histories at patients, flank pain in two, both
Box 0030, 1500 E. Medical Center Dr., Ann Arbor, MI 481 09-0030. Ellis. 2 Department
Subjects Subjects
to J. H.
and
mild
flank
pain
and
nine women), ranging from 24 to 64 (mean, 40.5) years old, for treatment of stone-bearing or non-stone-bearing infected presentation included recurrent urinary tract infections in two urinary tract infection and flank pain in five, gross hematuria occasional
abscess surgically drained, apparently
MI 48109. address:
Radiology
Ltd.,
85716.
Tucson,
AZ
had pyelolithotomies diverticula contained
0361-803X/91/1565-0995
extracorporeal
© American Roentgen Ray Society
isfactory
passage
hematuria
in another.
Two
patients
arising within the caliceal diverticula.
had
had
a renal
Four patients had
of the ipsilateral kidney at other institutions, but it is not known if the stone at the time of the previous procedures. Two patients had had
shock-wave of fragments.
lithotripsy
(ESWL) of their stone-bearing
diverticula
without
sat-
996
ELLIS
ET AL.
Fig. 1.-A,
AJR:156,
May 1991
cluster
of 25 small
Plain film shows
stones.
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B, Retrograde pyelogram shows that stones are contained in a caliceal diverticulum arising from upper pole of left kidney.
A
B
Preprocedure
injection of methylene
Studies
via the
Each
patient
immediately
had a retrograde
before
the
or antegrade
procedure
pyelogram
to evaluate
renal
anatomy.
obtained Ten
of
the 12 diverticula the right kidney.
were found in the left kidney, and two occurred in Eight were located in the upper pole, three in the midpole, and one in the lower pole. Others have also noted that upper
calices
are the most frequent sites of both diverticula and [1 , 2]. More than half of our diverticula arose from posterior calices. All were Type I diverticula (arising from a minor calix) by the criteria of Wulfsohn [8]. The diverticula ranged in size from 8 by 10 mm to 25 by 48 mm. Stones were present in 10 diverticula and ranged in size from 2 to pole
diverticular
27 mm.
stones
Four
diverticula contained single stones; the rest had as (Fig. 1). One patient had an incidental ipsilateral diverticulum, which did not contain stone and was not treated.
as 25 stones
many
second
indirect
who
had
with
analgesia (meperidine, Eleven ulum.
patients
In two
system with
a drainage
punctures
at another catheter
already
were administered.
into the caliceal
approach
One patient
had had an indirect
performed
or diazepam)
direct
an intercostal
12th ribs was required. diverticulum
midazolam,
received
patients,
under fluoroscopic guidance after consent. Local anesthesia and IV
between
with an upper
puncture
hospital in the
into
the
divertic11th
and
pole stone-bearing
the lower
pole
collecting
and was sent to our institution renal
a flexible
either
1 2-French
with
manual
dilators
or
30-French
with
a balloon
catheter.
Access to the neck of the diverticula in the 1 1 directly punctured cases was attempted on entry and was successful in three cases, leading to placement of safety wires. One of these cases was the infected diverticulum in which the access tract was dilated to only 1 2-French and no nephroscopy was performed. In the eight remaining
cases, the safety wire was coiled in the diverticula neck was applicable,
sought stone
neck in the patient
catheterized
by using
treated
fluoroscopy.
had
nephroscope
the
upper
pole
was
in the
reverse
and
basket.
forceps
out
approach
had
At our center,
one
pelvic
attempts
were
stone
to enter
unsuccessful
of the
upper
diverticulum
pole
The
both
nine
cases
suctioned
in which
before
access
catheter
in either cases)
indirectly
to
the
(Fig.
approached
case
neck,
necks
to was
ranging
on whether left
via
attached
catheters
we
flushed
infused
diverticular
Depending
diverticular
the diverticulum 3) for drainage
the
the
retrieved
were
agent
balloon
after
when
were
stones
contrast
to
with
and
pelvis and
out with a catheter
access
at
balloon catheter. three stones fell
renal
seven
with
obtained, the necks were dilated size from 18-French to 30-French. achieved
the
position
remaining
diverticulum
catheter (Fig. 2) and then a syringe. In the
into
Trendelenburg
extracted
the diverticulum
of the diverticular neck with an 18-French at the time of the second nephroscopy,
of
(eight
pelvis.
The nine nephrostomy tracts placed directly into stone-bearing diverticula were dilated with balloon catheters ranging in size from 24-French to 30-French. The indirect access tract was dilated to 26French. The tracts into the two infected diverticula were dilated to
indirect
institution.
dilatation However,
with
performed informed
the
the other
patient
All procedures were the patient had given
was
Methods used for stone extraction were rigid nephroscopy with forceps and ultrasonic lithotripsy, flexible nephroscopy with baskets, and simple suction with catheters. Of the 10 patients with stonebearing diverticula, complete extraction was accomplished in a single sitting at the time of the original puncture in six. One patient who underwent ESWL after an initial nephrostomy into the diverticulum for drainage had all of his fragments removed at a single subsequent nephroscopy. One patient required two nephroscopic procedures to remove stone, and one patient required three procedures. The patient
out Procedures
blue. The diverticular
approach
a large
Malecot
(three cases) or the renal pelvis and cavity obliteration in all but the
in which
no attempt
was
made
to oblit-
erate the diverticulum. After allowing the tract to mature for 2-4 days, we attempted diverticular obliteration with Bugby electrodes endoscopically in six of the 1 0 stone-bearing and one of the infected diverticula.
which which
After
fulguration,
drainage
catheters
were
not
replaced,
allowed drainage
the cavity and tract to close, except in one case in was continued with an 8-French nephrostomy tube for 2 days before tube removal. Tetracycline for sclerosis was infused twice in aliquots of 7 ml each, separated by 9 days, into the other infected
diverticulum.
the diverticulum
This
volume
was
chosen
to fill but
and was left in place for 5 mm before
not
distend
aspiration.
and the diverticular
via nephroscopy after tract dilatation and, where extraction. In five of these patients, nephroscopy was successful in directing a guidewire through the diverticular neck under direct visualization, aided in some cases by the retrograde
in
or not we
Follow-up In eight kidney
was
patients, available
clinical
and
(range,
4 months
radiologic
follow-up
to 6 years;
of the
mean,
involved
1 6 months).
AJR:156.
RENAL
May 1991
CALICEAL
DIVERTICULA
997
Fig. 2.-Lateral pyelogram of case with mdirect approach. Cluster of stones (white arrow) surrounded by contrast material is identified within diverticulum. Angled catheter (white arrowhead) has been manipulated into diverticulum for flushing of stones from cavity via contrast
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injection.
Note angulation
required
to enter di-
verticulum, making nephroscopy impossible. Ureteral catheter (black arrow) and safety oatheter containing guidewire (black arrowhead) are present. Fig. 3.-Pyelogram shows stenting of caliceal diverticulum with 24-French Malecot catheter after stone extraction and dilatation of diverticular neck. Wings of Malecot positioned within renal pelvis. 8-French extension lies within ureter
as protection
against loss of access if tube is
partly withdrawn inadvertentiy. Diverticulum is not opacified because it is filled by stent, but approximate location along course of tube is marked (D).
Fig.
4.-Caliceal
diverticulum
containing
stone and transitional cell carcinoma. A, Plain film shows stone material in right kidney (within diverticulum). B, Retrograde pyelogram shows soft-tissue
mass
representing
within
opacified
Two
patients
were
roureterectomy yet
reached
transitional
cell carcinoma
diverticulum.
for the
lost
to follow-up,
transitional
4-month
follow-up
cell
and
one
carcinoma.
had One
an interval patient
nephhas
period.
Results Stone
Infected
Diverticula
not
In the infected diverticula, cultures of aspirated showed no growth in one patient and minimal Proteus organisms in the other. Both patients treated with antibiotics before the procedures.
contents growth of had been
Extraction
Complete stone extractions were accomplished in all i 0 stone cases. One of the patients was found at the time of stone extraction to have a well-differentiated transitional cell carcinoma in the diverticulum in addition to the stone (Fig. 4). The mass had been visualized as a filling defect on a previous retrograde pyelogram and had increased in size on the retrograde pyelogram performed immediately before puncture. However, this enlargement was attributed to thrombus in this patient, who had presented with gross hematuria. The stone was removed via nephroscopy and excisional biopsy of the mass was performed. The patient subsequently elected to have a nephroureterectomy with excision of the drainage tract because of the possibility of tract seeding. Most stones were found to be mixtures of calcium oxalate monohydrate and hydroxyapatite. None of the stones were composed of cystine or uric acid.
Complications Minor complications included hemorrhage during the initial effort in three patients. This obscured the nephroscopic field and led to performance of the procedure in two stages. No transfusions were required. One of the patients who underwent an intercostal puncture developed a pneumothorax but did not require chest tube placement. One patient experienced transient hypertension and tachycardia during the procedure. One patient had mild extravasation of irrigant from the diverticulum; she experienced pain with fulguration, which obligated a second sitting to complete. Our only major complication was a urinoma from perforation of the renal pelvis with resultant pain and fever, which lengthened the patient’s hospital stay. The problem resolved with IV antibiotics and catheter drainage of the urinoma.
ELLIS
998
ET AL.
AJR:156,
Fig. 5.-Successful
verticulum A,
obliteration
by percutaneous
Preprocedure
May 1991
of caliceal
di-
techniques.
excretory
urogram
shows
lobulated caliceal diverticulum (arrows). Stone material is obscured by contrast material. Over-
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lying parenchymal thickness is reduced (arrowhead), typical for diverticula. B, Follow-up tomogram during excretory urog-
raphy at 13 months shows nonvisualization diverticulum. Focal loss of overlying chyma (arrowhead) again is seen.
Follow-up In six
patients
in whom
cavity
obliteration
was
attempted
by fulguration and in whom follow-up is available, nonvisualization of the diverticulum on careful follow-up excretory urography indicated successful obliteration (Fig. 5); this nonvisualization represented a change from preprocedural excretory urograms, which had shown the diverticula. One of these patients is asymptomatic but takes prophylactic antibiotics to prevent recurrent urinary tract infections; the others are entirely free of symptoms. One patient who underwent only catheter drainage of her diverticulum has had recurrence of her flank pain. Excretory urography 30 months after the procedure showed a persistent cavity in which stone has recurred. In the patient who underwent tetracycline sclerosis, the cavity persists on follow-up studies but the patient has remained asymptomatic. The patient who was found to have transitional cell carcinoma has been free of any evidence of tumor recurrence.
Discussion We were able to treat successfully 1 2 symptomatic caliceal diverticula, 1 0 of which contained stones, with percutaneous techniques. In those patients in whom fulguration with a Bugby electrode was performed and follow-up is available, no stones have recurred and the diverticula are no longer seen on excretory urography. Two diverticula are known to persist: one infected diverticulum in which tetracycline was used as the sclerosing agent, and one stone-bearing diverticulum in which tube drainage only was used. In the latter case, stone has recurred 30 months after the procedure. Although we were successful in extracting stones in a patient whose caliceal diverticulum had been approached indirectly
elsewhere,
ture the involved
we prefer,
diverticulum
as do others directly.
[3, 6], to punc-
The two major
advan-
of
renal paren-
tages of direct puncture are the ability to use the rigid nephroscope and the ability to treat the diverticular abnormality without accessing the diverticular neck, should this prove to be difficult. The ability to use rigid nephroscopy is a distinct advantage of the direct-puncture
approach.
The
better
optics
and
larger
irrigation channel of the rigid instrument are unquestionably beneficial in one-stage procedures for immediate visualization of the renal anatomy and stone if present, particularly in the presence of the bleeding that accompanies puncture and tract dilatation. Irrigation flow is much less through the smaller channels of the flexible nephroscope, and flow is further reduced when one channel is occupied with an instrument [9]. The rigid scope admits larger extraction instruments, and the ultrasonic lithotripsy available with the rigid scope is much more efficient in stone disintegration than the electrohydraulic lithotripsy of the flexible scope, especially for larger stones. Several other difficulties with the flexible nephroscope have been described [9]. For stone extraction or cavity fulguration with the indirect approach, the neck of the diverticulum must be located and the scope passed through it, a task that may be difficult or impossible, as we discovered in our indirectly approached
case, even with balloon dilatation This
difficulty
is avoided
of the diverticular
when
the
direct
neck (Fig.
is chosen. Ideally, with a direct diverticular puncture, the original guidewire and safety guidewire are inserted through the diverticular neck into the renal collecting system as a precaution against loss of access [3]. However, when access to the neck is not possible before tract dilatation, both wires can be coiled within the diverticulum. Lang and Glorioso [6] reported the successful use of a single guidewire in diverticular stone extractions when access to the neck was not obtained before dilatation. We have found it easy to place the second guidewire within the diverticulum and value the security it provides. 2).
approach
AJR:156.
In our
series,
large-caliber fulgurating obliterating
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single
RENAL
May 1991
diVerticular
approach fulguration,
the lining by stenting with a tube followed a few days later by electrode proved to be successful in
traumatizing
nephrostomy with the
case.
a Bugby cavity, whereas
In contrast,
stenting
alone
was
not
in a
Hulbert
et al. [3] reported successful obliteration in five stone cases using a direct and nephrostomy drainage for 2 weeks, without believing that the trauma of dilatation and ensuing
formation of granulation to obliterate the cavity. fulguration it was
CALICEAL
tissue around the tube The same group reported
to obliterate
thought
that
by the percutaneous diverticulum
might
parenchyma
[4].
a large
only
part
caliceal
diverticulum
of the lining
access
Obliteration
by the
firm,
of an infected
because
be traumatized
might
and because
be retarded
is sufficient the use of
shrinkage
of the
supporting
renal
diverticulum
has
been successfully accomplished with percutaneous drainage and stenting in one case [5], but was unsuccessfully attempted with percutaneously injected absolute alcohol in an infected
diverticulum
with
without
fulguration [3].
proaches cavity
obliteration
an occluded
have
neck
not
[7].
been
Indirect
ap-
successful
in
Unfortunately, no single center has enough cases for a wellcontrolled study comparing various modifications of percutaneous treatment of caliceal diverticula. Currently, we briefly attempt to access the neck ofthe diverticulum fluoroscopically upon entry, but it is often easier to place a wire across the neck nephroscopically after stone removal, aided by retrograde injection of methylene blue. After balloon dilatation of the diverticular neck, the neck is stented with a 24-French Malecot catheter. After the tract matures, typically in 48 hr, we proceed to fulguration of the diverticulum and its neck. If no problems occur, we remove all tubes immediately after fulguration, but occasionally tube in place for access
cavity shrinkage. We recommend cause we believe epithelium
within
we have
and/or
fulguration something the
rather should
diverticular
left a small
tube
nephrostomy
injections
to assess
than stenting alone bebe done directly to the
cavity
to incite
scar
forma-
tion. Stenting alone might only scarify the diverticular neck. The natural history of a diverticulum whose neck is isolated from
the collecting
system
is unknown;
theoretically
the resid-
ual cavity could become infected. A randomized study would be needed to compare the efficacy of fulguration vs stenting alone. However, fulguration under direct vision is easily controlled and adds no morbidity and very little time to the procedure.
Furthermore,
we
usually
remove
all tubes
after
and the patient can be discharged tube-free. In contrast, we discontinued our attempts at sclerosis with tetracycline after a single case because of the technical difficulties in calculating dosage and the potential hazards of fulguration
extravasation
tern. We believe fluoroscopic
before
or entry
that
careful
contrast
fulguration.
of tetracycline
into
inspection
injection
One should
with
the
with spot
collecting
sys-
nephroscopy
films
should
look for a flattened
and be done
renal papilla
and observe the anatomy of the neck. It is reasonable to fulgurate caliceal diverticula, as they are lined with nonsecretory endothelium [8]. However, should the presumed caliceal diverticulum
be in fact
a hydrocalix,
fulguration
of the
tract
DIVERTICULA
999
and portions of the cavity could lead to obstruction of the draining collecting ducts. The result could be focal renal parenchymal loss or redevelopment of the cavity and infection leading to abscess formation. We have percutaneously extracted stone from a patient not included in this series who appeared to have a caliceal diverticulum on initial retrograde pyelogram,
but which
looked
like a calix
on nephrostomy
tube
injection. A limitation of our study is that radiologic follow-up was limited to excretory urography. We are satisfied that, in those patients with follow-up urograms, at least the necks were obliterated because the diverticula had been identified on preprocedural excretory urography, and we feel that retrograde pyelography would not be useful. CT or sonography would be necessary to assess any residual cavity within the parenchyma, but this information is not available in our series or that of Hulbert et al. [3]. ESWL has replaced percutaneous nephrolithotomy in at least 90% of patients with nondiverticular renal calculi [10], but it has not been widely used in the treatment of diverticular calculi because the stone fragments may not pass through the narrow diverticular neck [1 i ]. Psihramis and Dretler [i2] have recently reported their experience with ESWL for treating 1 0 patients with diverticular calculi. Although all stones were completely fragmented in one or two treatments, only two patients had passed all stone fragments after a minimum follow-up period of 3 months. Three patients (30%) had persistent symptoms. Although we have successfully treated one diverticular stone with ESWL alone despite a narrow neck, two other diverticula (included in this series) treated with ESWL were referred for percutaneous stone extraction because of the inability of fragments to drain. Although primary use of ESWL for diverticular calculi has been proposed both for its low morbidity and the possibility of applying it in centers without extensive experience in percutaneous techniques [12], we believe that primary percutaneous nephrolithotomy is the optimal approach unless specific contraindications supervene. Percutaneous techniques have the advantage of treatment of the diverticulum at the same time as removal of the stone. Elimination of the underlying abnormality will reduce the chance of recurrent stones or infection. We have had no recurrences of stone in any patient who had successful cavity obliteration, but stone did recur in one of the two cases in which the cavity was not obliterated. Furthermore, some complications of ESWL are best treated with percutaneous techniques, so that it may be unwise to use ESWL for complex cases in which percutaneous techniques are not readily available. Two of our patients required percutaneous diverticular stone extraction when fragments failed to pass after ESWL. ESWL may be appropriate initial therapy in cases in which a percutaneous approach would be difficult. For example, a disadvantageous position such as a diverticular location centrally near the renal vessels or high under the ribs increases the
risks
of
hemorrhage
or
pneumothorax.
Percutaneous
techniques can be used later if ESWL fails. The most important factor that would lead us away from percutaneous treatment is the size of the diverticulum. Smaller diverticula are more difficult to puncture and to coil wires within. We suc-
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i 000
ELLIS
cessfully treated a diverticulum measuring 8 by 1 0 mm and believe that in experienced hands, favorably positioned diverticula as small as 6 or 7 mm might be treated. If wires cannot be coiled in the diverticulum or advanced through its neck, then the technique described by Glanz et al. [1 3] for difficult caliceal stones could be attempted. This involves puncturing the far wall of the cavity and anchoring guidewires in the adjacent renal parenchyma.
We conclude that percutaneous nephrostomy and nephroscopy provide a safe alternative to an open procedure for the treatment of infected or stone-bearing diverticula. Whenever possible, obliteration of the cavity should be attempted to reduce the chance of recurrence of symptoms.
ET
AL.
1 . Middleton AW Jr. Pfister RC. Stone-containing pyelocaliceal diverticulum: embryogenic, anatomic, radiologic and clinical characteristics. J Urol 1974;1 11:2-6 2. TimmonsJW Jr. Malek RS, Hattery RR, DeWeerd JH. Calicealdiverticulum. J Urol 1975:114:6-9 3. Hulbert JC, Reddy PK, Hunter DW, Castaheda-ZCiniga W, Amplatz K,
May 1991
Lange PH. Percutaneous techniques for the management of caliceal diverticula containing calculi. J Urol i986;135:225-227 4. Hulbert JC. LaPointe S, Reddy PK, Hunter DW, Castaheda-Zu#{241}iga W. Percutaneous endoscopic fulguration of a large volume caliceal diverticulum. J Urol 1987;138: 116-117 5. Kremers PW, Beckmann CF. Bihrle W, III. Percutaneous balloon dilatation in treatment of infected pyelocaliceal diverticulum. Urology i988;32: 29-32
6. Lang EK, Glorioso LW. Multiple percutaneous
access routes to multiple
calculi, calculi in caliceal diverticula, and staghom calculi. Radiology i986;158:21 1-214 7. Ramchandani P. Soulen RL, Kendall AR, Davis JA. Percutaneous management of a pyelocaliceal diverticular abscess. J Urol 1985;133:81-83 8. Wulfsohn MA. Pyelocaliceal diverticula. J Urol 1980;1 23: 1-8
9. Lange PH, Reddy PK, Hulbert JC, et al. Percutaneous
10.
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