Page 2178 - Cote clinical veterinary advisor dogs and cats 4th

1086 Cystoscopy

○ Rigid endoscope sizes most commonly • Urinary tract rupture can result from inap- of the scope. The scope and calculus are
used range from 2.7-5 mm in diameter, propriate technique (e.g., overfilling, pushing then withdrawn simultaneously. The size
VetBooks.ir ranging from 3.8-6 mm; length of the pre-existing disease. Care should be taken the usefulness of this technique and lead
with respective cannula (sheath) diameters
of the calculus or its fragments can limit
without visual path) and/or weakness from
during biopsy of abnormal tissue (e.g.,
to surgery or percutaneous cystolithotomy
scopes ranges from 7-30 cm. The cannula
(PCCL).
usually includes the associated biopsy,
infusion, and outflow ports. Smaller scopes the site of remnant urachal diverticula, • The endoscope is withdrawn slowly while
intramural neoplasm).
may have the outer cannula and ports • Urethral mucosal edema due to ongoing observing for abnormalities. Visualization of
combined into one single unit. inherent trauma from endoscopy can be a the urethral mucosa is often superior during
○ A 0° viewing angle may be better for limiting factor in uroendoscopy. withdrawal of the endoscope.
viewing the urethra, and a 30° viewing • Have available catheter or lubricated guide • Ectopic ureteral openings in the urethra
angle may be preferred for viewing the wire to use as stylet through tumor-narrowed (sometimes multiple sites) can be identi-
bladder. passages. fied. Cystoscopy can be more accurate for
○ A bridge is used for connecting some • Do not rely on visual impressions, but obtain diagnosis of ectopic ureter than imaging
scopes with their cannulas and to provide samples for histopathologic or cytologic assay. studies.
additional access ports (generally one or • Might not achieve goals (diagnostic, • In the male dog, the colliculus seminalis
two) for flushing or infusion of saline and therapeutic) is located dorsally and can be seen more
passage of other instruments. prominently in intact dogs, along with
○ The Albarrán lever is a deflecting bridge Procedure the associated prostatic and deferent duct
that forces flexible biopsy instruments to • If the urine is turbid and dark or there is openings into the proximal urethra.
exit the bridge at an angle; this facilitates gross hematuria, it may be best to empty • The vaginal area is again reviewed, and if
biopsy and grasping of structures that are the bladder before the procedure. appropriate, this is the best time to obtain
almost parallel to the scope. • Ventral or dorsal recumbency; the author biopsies or brush cytologic samples or
○ The Ellik evacuator allows rapid saline prefers dorsal recumbency, but it can be to perform procedures such as balloon
lavage to provide for collection of small advantageous to reverse the initially selected bougienage.
calculi when attached to a rigid cystoscope position.
cannula. • The perineum and prepuce/vulva are Postprocedure
○ Rigid scopes tend to provide superior cleansed. • Postprocedural urethral obstruction due
images. • For female dogs and cats, the fiber endoscope to mucosal edema or inflammation occurs
or assembled rigid scope is placed in the infrequently and is usually correlated to the
Anticipated Time vulva, and the vulvar skin is gently pinched severity of the pathology present. Monitor
About 30-75 minutes, depending on ease of externally by an assistant to create a seal; then micturition until normal voiding is seen.
passage, extent of lesions, and whether the a saline infusion is started until the vault is • Use appropriate pain management.
procedure is diagnostic or also therapeutic distended.
(e.g., stone retrieval) • Examine the vulvar and vaginal areas to Alternatives and Their
the level of the cervical os, and identify the Relative Merits
Preparation: Important urethral orifice; then cannulate the urethra Laparoscopic-assisted PCCL is more invasive
Checkpoints with the scope. The urethra is distended with and carries greater equipment requirements. It
• Have clear goals for the procedure based on inflow of saline as the scope is advanced may be used when larger tumors obstruct the
case assessment, and perform sonographic to the bladder. The bladder is emptied as trigone or urethra, for removal of more calculi,
and radiographic imaging first. needed through the biopsy channel of the or for placing a retrograde catheter or guide
• Know the appearance of normal structures fiberscope or outflow port of the cannula. wire to facilitate antegrade catheterization of
in the lower urinary tract. • For male patients, the technique is similar, an obstructed urethra.
• Plan ahead for staff involvement with setup, except that the prepuce is held to form a
procedural assistance, and cleaning the seal around a flexible fiberendoscope. The Pearls
equipment. limiting diameter is the passage through the • Be vigilant about the degree of filling of the
• Discuss with owner the risks and that os penis. In some instances, male dogs may bladder to avoid bladder overdistention or
repeated procedures may be required (e.g., also have the pelvic and proximal urethral rupture.
incomplete stone retrieval, failure to dilate segments examined using a rigid urethro- • Try to avoid cystocentesis for 24 hours before
stricture). cystoscope through a temporary prepubic cystoscopy because it can leave points of
• Have alternative plans for surgery if war- perineal urethrostomy. iatrogenic hemorrhage in the mucosa.
ranted and goals are not achieved. • The bladder is examined in a methodical • Plan ahead if a retention urethral catheter
• Pre-procedure enemas can reduce interference pattern to include the apex to the trigonal should be placed after cystoscopy.
by colorectal feces (can lessen mechanical region. Adequate distention is created and • Examine the contents of the outflow urine
depression of adjacent urinary structures but maintained with saline flow through the collection bag for small calculi that might
may increase risk of fecal contamination of inflow port. It is important to visualize the have gone unseen initially.
perivulvar region) (p. 1099). appearance of mucosa when the bladder is
less distended and when filled. SUGGESTED READING
Possible Complications and • The ureteral orifices are identified, and in Morgan M, et al: Cystoscopy in dogs and cats. Vet
Common Errors to Avoid many cases, pulsatile flow of urine can be Clin North Am Small Anim Pract 45:665-701,
• Iatrogenic UTI observed. Biopsies are taken for histopatho- 2015.
• Mistaking the fossa clitoridis in female dogs logic evaluation and culture. Calculi may be AUTHOR: Mark E. Hitt, DVM, MS, DACVIM
for the urethral orifice examined and samples taken for analysis. EDITORS: Leah A. Cohn, DVM, PhD, DACVIM; Mark S.
• Prior digital- or catheter-induced trauma and Calculi may be larger than the lumen of Thompson, DVM, DABVP
edema to the urethral tubercle (papilla) or the cannula channel. If smaller than the
urethra can hinder entry of the endoscope urethral limitation, these larger calculi may
into the urethra. be drawn up to and held against the end

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