Surgery of urinary tract - Urethra + Ureters

Question 1

Are males or females more prone to urethral disease?

Answer 1

Males

Question 2

What are the 3 regions of a male urethral tract?

Answer 2

• Prostatic
   At neck of bladder
   Surrounded by prostate
• Pelvic
   From prostate to ischial arch
   Can be injured due to pelvic fractures
• Penile
   Ischial arch to orifice
   Prone to obstruction, does not distend

Question 3

What are the congenital abnormalities of the urethra?

Answer 3

• Hypospadias:
  failure of fusion of the urogenital folds, incomplete formation of the urethra (abnormal urethral opening, more common in males)
• Epispadias:
  failure of fusion of the dorsal penile urethra
• Urethral fistulas
   urethrorectal : developmental abnormality of fetal cloaca
   Urethrocutaneous
   Can also be acquired

Question 4

What are the acquired disorders of the urethra?

Answer 4

• Urethritis
• Urethral prolapse
• Urethral trauma
• Urethral stricture
• Urethral obstruction
• Neoplasia

Question 5

What can cause urethritis?

Answer 5

UTI
urolithiasis
neoplasia
iatrogenic trauma

Treat underlying cause

Question 6

What are the causes of urethral prolapse?
What breeds are at risk?

Answer 6

 Abnormal development of urethra?
 Increased intra-abdominal pressure due to laboured breathing?
 Urethral infection?
 Sexual excitement?
Brachycephalics - bulldog

Question 7

What are the clinical signs of urethral prolapse?

Answer 7

 Licking of penis
 Bleeding
 Protrusion of urethral mucosa through external urethral orifice of penis

Question 8

What are the treatments of urethral prolapse?

Answer 8

 Reduction of prolapsed segment if protrusion minimal and asymptomatic: catheterise urethra and
place purse string in tunic of penis at external urethral orifice for 5 days
 Resection of prolapsed tissue: haematuria for few days postop
 Castration
 Recurrence

Question 9

What is the most common urethral disease?

Answer 9

Urethral obstruction

Question 10

What happens if an urethral obstruction isn’t treated?

Answer 10

• Requires urgent management, otherwise:
   Uraemia and death
   Prolonged bladder distention > loss of detrusor muscle may be
  permanent

Question 11

What are the different causes of urethral obstruction?

Answer 11

• Urolithiasis (male dogs: caudal ro os penis or ischial arch)
• Urethral plugs (mucus and crystals, male cats/FLUTD, distal 3rd of urethra)
• Neoplasia (bladder tumours invading urethra)
• Granuloma
• Bladder displacement/herniation
• Strictures
• Trauma
• Prostatic disease (dogs)
• Fracture of os penis
• Blood clots due to idiopathic renal haematuria
• Idiopathic

Question 12

What are the clinical signs of urethral obstruction?

Answer 12

• Variable; depending on degree and duration of obstruction
• Dysuria
• Anuria
• Haematuria
• Dripping urine (owners may report ‘incontinence’)
• Abdominal distention
• Pain
• Signs of uraemia (>2days)

Question 13

How would you diagnose urethral obstruction?

Answer 13

• History
• Abdominal palpation
• Inability to pass urinary catheter
• Abdominal Radiography
   Plain radiographs (radio-opaque calculi)
   Positive-contrast urethrography (displaced bladder, radiolucent calculi, soft tissue
  lesions)
• Abdominal ultrasound

Question 14

How would you treat an urethral obstruction?

Answer 14

• Empty bladder – cystocentesis
• Fluid therapy
• Attempt urethral catheterization
   Under ga
   Pass catheter to obstruction and flush with saline
   Doyen (intestinal) clamps on penis to occlude urethra
   Empty bladder as saline will pass obstruction
• Once obstruction resolved pass advance u+ catheter in the bladder and empty it
• Cystostomy to remove calculi

Question 15

What is an urethrostomy?

Answer 15

Surgical procedure that creates a permanent opening from the urethra

Question 16

What can cause urethral trauma?

Answer 16

 Abdominal trauma
 Pelvic fracture
 Iatrogenic

Question 17

What are the clinical signs of urethral trauma?

Answer 17

 Haematuria, dysuria, anuria
 Pain
 Abdominal distention
 Signs of peritonitis
 Signs of uraemia

Question 18

How would you diagnose urethral trauma?

Answer 18

• History
• Radiography (plain and retrograde urethrogram)
• Haematology and serum biochemistry
• Attempt urethral catheterization to establish urethral patency
• Stabilise patient with fluid therapy

Question 19

How would you treat urethral trauma?

Answer 19

• For minor urethral trauma
   Conservative management: place urethral catheter for 5-10 days
• For extensive urethral trauma
   Surgical repair

Question 20

What animals tend to be affected by urethral tumours?
What type of tumours are more common?

Answer 20

• Old female dogs usually affected
• Less common than bladder tumours
• TCC and SCC more common
• Benign rare
• Metastasis in >50% of cases

Question 21

How would you treat/manage urethral tumours?

Answer 21

• Surgery usually is not an option
• Surgical resection and urethral anastomosis via pubic osteotomy??
• Cystostomy tube
• Non-steroidal anti-inflammatories (NSAIDs)
• Stent
• Treatment is palliative, prognosis poor

Question 22

What are the intraluminal, intramural and extramural causes of ureteral obstruction?

Answer 22

• Intraluminal
   Calculus
   Mass? Rare
• Intramural
   Fibrosis/stricture
   Mass? Rare
• Extramural
   Compression or invasion by abdominal tumour;
  rare except bladder tumours affecting the
  trigone
   Ligation of ureter during OHE

Question 23

What will ureteral obstruction lead to if not treated within a week?

Answer 23

Hydronephrosis

Question 24

What are the problems of ureteral surgery?

Answer 24

• Too small in diameter for safe surgery…
• Miscroscope/Loupes required; accurate surgery
• Risk of urine leakage
• Risk of healing by fibrosis which will cause stricture