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Ectopic Ureter 283

dorsolateral location but then tunnels with the kidneys, ureter (if visible), and correction or laser ablation by transurethral
through the submucosa of the bladder bladder cystoscopy.
VetBooks.ir location. Amenable to cystoscopic laser Advanced or Confirmatory Testing Acute General Treatment Diseases and Disorders
and opens distal to the normal trigone
Abdominal ultrasound (may be normal):
ablation
• Appropriate treatment of concurrent urinary
HISTORY, CHIEF COMPLAINT • Hydroureter tract infection (if present) is important before
• Hydronephrosis
surgery.
• Urinary incontinence, intermittent or • Ureterocele • Surgical technique used depends on the loca-
continuous • May see abnormal location of ureteral tion and morphology of the ectopic ureter.
• Recurrent urinary tract infections (typi- orifice Surgical techniques commonly performed:
cally causing pollakiuria, stranguria, and/ • Evidence of cystitis if secondary urinary tract ○ Ureteral reimplantation with ligation
or hematuria) infection of the distal ureter (extramural ectopic
Excretory urography (EU) with survey radio- ureters)
PHYSICAL EXAM FINDINGS graphs (p. 1101): ○ Neoureterostomy and urethra-trigone
• Moist or urine-stained hair in the perivulvar/ • Identify location of ureteral opening distal reconstruction (intramural ectopic ureters)
preputial region to the trigone of the bladder ○ Nephroureterectomy: removal of a non-
• Urinary incontinence may be noted during • Ureteral dilation (>0.09 times the length of functional kidney and associated ureter;
physical exam. the L2 vertebrae) considered a salvage procedure. Important
• Dermatitis due to urine scalding ○ Most commonly associated with intramu- to determine renal function in the
• Small or moderately sized bladder on palpa- ral ureters that open into the urethra or contralateral kidney is normal
tion (typically small) vagina • Cystoscopic-guided laser ablation
• Vulvovaginal stricture or persistent hymen ○ Due to intermittent or partial urinary ○ Laser ablation of the wall between the
palpated on digital vaginal exam obstruction and/or secondary to a urinary urethral lumen and the intramural ureteral
• Vulvovaginitis tract infection lumen is practical only for patients with
• Lateral, ventrodorsal, and oblique views are intramural ectopic ureters.
Etiology and Pathophysiology necessary to identify the distal segment of ○ Can be an effective, minimally invasive
• Ectopic ureters are the result of dysembryo- nondilated ureters. technique for correction of intramural
genesis of the ureteral bud of the mesonephric • Inability to consistently identify ectopic ectopic ureters
duct. ureter may be due to ureteral peristalsis, poor ○ Performed using a holmium:YAG or diode
• The deviation of the ureteral bud from the renal excretion of contrast, or superimposi- laser
normal position determines the location of tion of other structures. ○ Limited availability
the ectopic opening. • Diagnostic accuracy improves if combined
with pneumocystography. Chronic Treatment
DIAGNOSIS Contrast-enhanced CT scan (EU with CT): Management of concurrent urethral sphincter
• Sensitive and specific method for diagnosis mechanism incompetence, if present (p. 1011)
Diagnostic Overview and characterization of ectopic ureters (e.g.,
Ectopic ureters should be suspected in exact location of ureteral orifice, identifying Possible Complications
any young dog with urinary incontinence. multiple openings) • Hydroureter and hydronephrosis due to
Confirmation requires advanced imaging Transurethral cystoscopy (p. 1085): obstruction postoperatively
(abdominal ultrasound, excretory urography, • Direct visualization of the lower urinary tract • Persistent urinary incontinence: most
contrast-enhanced CT, or transurethral using a rigid or flexible endoscope common complication after surgical repair
cystoscopy). • Identification of ectopic ureteral openings, of ectopic ureters (40%-70% of patients)
but may be difficult to confirm intramural • Recurrent urinary tract infections
Differential Diagnosis nature of ureter with cystoscopy alone (CT
Differential diagnosis for urinary incontinence: or fluoroscopy may be useful for this) Recommended Monitoring
• Ureterocele • Allows for identification of other congenital Routine monitoring for urinary tract infections
• Pelvic bladder structural abnormalities of the lower urinary
• Urge incontinence (e.g., urinary tract infec- tract involving the bladder, vagina, vestibule, PROGNOSIS & OUTCOME
tion, urolithiasis) and urethra
• Urethral sphincter mechanism incompetence • Commonly paired with CT or performed • Prognosis with surgical repair or laser abla-
• Vaginal abnormality (e.g., vaginal stricture) alone by a skilled cystoscopist tion of ectopic ureter(s) is good if there is
• Neurologic disorders Urodynamic evaluation: no evidence of renal dysfunction before
• Congenital urethral incompetence or • Determination of the urethral pressure profile surgery.
hypoplasia may be useful in gaining information regard- • Prognosis for return of urinary continence
ing function of the urethra in patients with without specific therapy for urethral sphincter
Initial Database urinary incontinence. incompetence is poor, with up to 70% of
Urinalysis (may be normal): • Used to help predict continued postoperative dogs remaining incontinent postoperatively.
• Pyuria urinary incontinence in patients with ectopic Most dogs will improve with medical man-
• Hematuria ureter agement for urethral sphincter mechanism
• Bacteriuria • Limited availability incompetence.
Abdominal radiographs (often normal):
• Provide information regarding the size, TREATMENT PEARLS & CONSIDERATIONS
shape, and location of the kidneys and
bladder Treatment Overview Comments
• Small bladder size The treatment goal for patients with ectopic • Ectopic ureter(s) should be suspected in any
• Pelvic bladder ureters consists of correcting the abnormal young dog with urinary incontinence.
• Mainly used to rule out cystolithiasis and urethral orifice to resolve or reduce urinary • Although surgery is often successful for surgi-
identify structural abnormalities associated incontinence. This requires open surgical cal correction of ectopic ureters, 40%-70%

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