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Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 Shipov, A. 88
INTRODUCTION
Urethral obstruction is a common disorder in cats (1). It
occurs most commonly in young male cats due to urethral
plugs, and less commonly due to urethroliths, urethral stric-
ture, neoplasia and external urethral compression. Most cases
are managed medically, however a subset require surgical in-
tervention, among which perineal urethrostomy in the most
common (2). Te present report describes successful man-
agement of severe proximal urethral stricture associated with
trauma in a young male cat.
CASE REPORT
An 8 months old (estimated), male intact, stray cat, weigh-
ing 3.3 kg was presented to a local veterinarian due to inap-
petence, lethargy and dysuria. Te cat was found by his new
owners in lateral recumbency, soaked with urine. Te cat was
held indoors for few days during which time he presented
with severe stranguria, pollakiuria and urinary dribbling. On
presentation to the referring veterinarian, vital signs were
normal, however; a large and frm urinary bladder was pal-
pated. Te remainder of the physical examination was un-
remarkable. Blood work and urinalysis were not performed
since this was a stray cat. Te cat was anesthetized with
medetomidine (80 µg IM, Dormosedan, Orion Pharma,
Espoo, Finland) and a 3.5 Fr urinary catheter was inserted.
Resistance was felt few cm centimeters proximally to the
urethral orifce but with reasonable force the urinary catheter
was advanced to the bladder. Te cat recovered uneventfully.
Urine production was not quantifed, but was assessed to be
normal. Following recovery the cat improved and became ac-
tive. Phenoxybenzamine (Dibenyline, Mercury pharmaceuti-
cal Ltd., Croydon, UK) at 2 mg, PO, q12hr was administered
to decrease urethral tone. Tree days later, the urinary cath-
Successful Balloon Expandable Stent Placement in the Management
of Severe Proximal Urethral Stricture in a Cat
Shipov, A.,
1#
Zafrany, A.,
2#
Kahana, N.,
1
Peery, D.,
1
Sommer, A.,
2
Winkler, R.
2
and Segev, G.
1
*
1
Koret School of Veterinary Medicine, Te Hebrew University of Jerusalem, Israel.
2
Frishman Dizingof Veterinary Center, Tel Aviv, Israel.
#
First two authors equally contributed to the manuscript.
* Corresponding Author: Dr. Gilad Segev, Koret School of Veterinary Medicine, Te Hebrew University of Jerusalem, Israel. Email: gilad.segev@mail.huji.ac.il
ABSTRACT
Tis case report describes an 8 months old, male intact, stray cat, which was presented to a local veterinarian
due to inappetence, lethargy and dysuria. A large and frm urinary bladder was palpated. A urinary catheter
was placed, however a resistance was felt a few cm proximally to the urethral orifce. Positive urethrogram
revealed a 1 mm in diameter and 12 mm in length stricture in the proximal urethra. Due to the location and
the length of the stricture, balloon dilation and stent placement were considered the best treatment options.
Under fuoroscopic guidance the stricture was balloon dilated and a balloon expandable metallic stent was
placed across the stricture. Te cat recovered uneventfully and was able to urinate normally. Tis is the frst
report to describe a successful retrograde stent placement in a male cat that did not previously undergo
perineal urethrostomy.
Keywords: Urethra, Feline, Feline Interstitial Cystitis, Azotemia.
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 89 Urethral Stricture in a Cat
eter was removed, but the cat represented with stranguria and
pollakiuria and was not able to urinate; therefore a urinary
catheter was reintroduced. Resistance was felt once again at
the same location. Tree days later the urinary catheter was
removed, however the cat was still unable to urinate.
Survey radiography raised the suspicion of a healing frac-
ture at the greater trochanter of the femor. Positive contrast
urethrocystography documented a stricture in the proximal
urethra. Due to the location and the length of the stricture,
balloon dilation and stent placement were considered the
best treatment option. Te cat was referred to the Hebrew
University Veterinary Teaching Hospital for further assess-
ment and treatment. Pre-anesthetic blood work (i.e., com-
plete blood count and serum biochemistry) was unremark-
able. Te cat was anesthetized and the perineal area was
clipped and aseptically prepared. A marking catheter with
10 mm markings was placed within a red rubber tube into the
colon. A urinary catheter was then introduced into the distal
urethra and a positive contrast urethrogram was performed
to measure the stricture diameter and length and to select an
appropriate size stent (Figure 1). Based on the measurements
performed under fuoroscopic guidance, a 1 mm in diameter
and 12 mm in length stricture was confrmed. Severe dila-
tation of the urethra was also identifed proximally to the
stricture (Figure 1), likely resulting from the long standing
obstruction. A 0.010 Fr guidewire was placed through the
Figure 1:
A) Fluoroscopic image of positive contrast retrograde urethrogram before stent placement. A marking catheter was placed in the colon to enable
accurate measurements of the stricture diameter and length. Note the severe stricture in the proximal urethra (white arrowhead) and the marked
dilatation proximally to the stricture (white arrow).
B) Fluoroscopic image of the stent after its deportment (white arrowhead).
C) Fluoroscopic image of positive contrast retrograde urethrogram after stent placement.
D) Survey radiographs two weeks after the procedure depicting the stent (black arrowhead).
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 Shipov, A. 90
urinary catheter. Once indentifed in the urinary bladder,
the urinary catheter was removed and a 1.5 mm in diameter
and 15 mm in length balloon was inserted and placed under
fuoroscopic guidance along the stricture. Te balloon was
dilated and left in place for few seconds until ruptured. Te
balloon was then removed and a balloon expendable metal-
lic stent, 18 mm in length with a maximal diameter of 2.8
mm was placed over the guide wire, under fuoroscopic guid-
ance (Figure 1). Te stent was then deployed and the bal-
loon was removed. Following stent placement, positive con-
trast radiography revealed complete opening of the urethra
(Figure 1). Te cat recovered uneventfully, and immediately
was able to urinate normally. Incontinence was not noted. In
the subsequent days the cat showed mild pollakiuria which
spontaneously resolved. Two weeks later, survey radiographs
were performed confrming the correct location of the stent
(Figure 1).
DISCUSSION
Urethral obstruction is a common disorder in male cats (1,
3). It occurs most commonly in young cats due to urethral
plugs, and less commonly due to urethroliths, urethral stric-
ture, neoplasia and external urethral compression (3).Te
cause of the urethral stricture in this cat cannot be defnitely
determined, as it was previously a stray cat and medical his-
tory was not available; however, considering his young age
and the presence of a femoral fracture, it most likely resulted
from trauma and potentially previous urethral tear that re-
sulted in a stricture.
Most cases of urethral obstruction are managed medi-
cally and obstructions are relieved by urinary catheterization.
Medical management is directed at correcting fuid and elec-
trolyte imbalances and decreasing urethral tone (e.g., alpha
antagonists) (1). In a subset of cats, medical management
fails, or is inappropriate (e.g., strictures), and surgery is indi-
cated to relive the obstruction (2).
Perineal uerthrostomy (PU) is most commonly employed
procedure for distal urethral strictures (4). In the case pre-
sented herein the obstruction was proximal and therefore
PU was not a valid option. Surgical options for proximal
urethral strictures are limited and include subpubic urethros-
tomy, transpelvic urethrostomy, resection and anastomosis,
and temporary or permanent cystostomy tube placement (5).
Tese procedures are not commonly performed and are as-
sociated with high complication rate, including stricture for-
mation urine leakage, dehiscence, skin necrosis, incontinence,
recurrent urinary tract infections and perineal herniation (5).
Interventional radiology is gaining popularity in veteri-
nary medicine during the last years (6). Urethral stents are
placed in increased frequency to relieve obstructions in the
urethra, mostly in dogs, as a palliative measure to treat ure-
thral obstruction due to neoplasia (7). Complications of ure-
thral stenting include incontinence, re-obstruction, and dam-
age to the urethral mucosa (7). In this case, stent placement
was considered a valid option due to the location and length
of the obstruction. Resection and anastomosis was consid-
ered not feasible in this case due to the length of the stric-
ture, while othe rsurgical alternatives would have resulted in
substantial alteration of the normal anatomy, and thus were
not considered the frst therapeutic option.
Few case reports and case series have documented stent
placement in cats with benign and malignant urethral ob-
structions (8-11). In most reported cases, self-expendable
metallic stents were used (7, 8, 10). In this report due to
stricture characteristics, stent availability, and fnancial con-
straints a balloon expandable metallic stent was used. Te
small stent and delivery system used in this case allowed ret-
rograde stent placement, despite the fact that this was young
male cat. Tis is in contrast to previous reports (8, 10, 11),
in which retrograde stent placement was performed in male
cats only following PU. Otherwise, urethral stents in male
cats had to be placed in an antegrade fashion (8, 10, 11).
Retrograde stent placement in the current case was feasible
due to the small diameter of the stricture.
Te stricture of the cat in the present report was not typi-
cal due to its length and location. When stents are placed in
the proximal urethra of cats, one should bear in mind the
relatively distal location of the ureters in the vesico-urethral
junction. Laser cut balloon expendable stents, such as the one
used in this procedure, have the advantage of maintaining
their length after deployment, and are recommended for re-
lieving urethral obstruction (7). Tis is unlike some other self
expandable metallic stents which undergo shortening after
deployment (7). Te use of a laser cut stent assisted precise
placement to avoid the cat’s ureters in this case. Te disad-
vantage of balloon expandable stent, compared with self-ex-
pendable stent, is the higher potential for mucosal damage.
Self-expandable laser cut metallic stents are more fexible
and potentially less traumatic as these expand more gradu-
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 91 Urethral Stricture in a Cat
ally based on the urethral diameter. To minimize damage to
the urethral mucosa, a balloon was initially used to verify that
the stricture can be dilated and to minimize urethral damage
when deploying the stent (6).
Urethral obstruction in cats occurs most commonly at a
young age (1), and so do strictures which complicates this
disorder. Urethral stents, if selected as a solution to relieve
the obstructions, are thus expected to be in place for a long
period of time. It is yet to be determined whether stent place-
ment is associated with a lower complication rate compared
to PU, when the latter is feasible. Due to the proximal loca-
tion of the stricture and its length most of the surgical op-
tions could not have been applied in this cat. Stent placement
allowed the preservation of the normal anatomy, and for the
ability to perform the aforementioned surgical procedures,
if unmanageable complications occur.
In summary, this case report describes successful balloon
expandable stent placement in a cat as a treatment from prox-
imal urethral obstruction and is the frst to be performed in
a retrograde fashion in a male cat that did not undergo PU
prior to the procedure.
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Case Reports