Contributors: Philip Lhermette, Elise Robertson

 Species: Canine   |   Classification: Techniques

Introduction Requirements Preparation Procedure Aftercare Outcomes Further Reading


  • Transurethral cystoscopy/vaginoscopy.



  • Complements other diagnostic imaging techniques (eg radiography and ultrasonography).
  • Increased diagnostic accuracy compared to contrast procedures.
  • Provides means of selectively obtaining biopsy specimens under direct visualization.
  • High definition images are in color and can record still images and video clips for monitoring progression/regression of disease.
  • Compared to traditional cystotomy Cystotomy , cystoscopy offers a well illuminated, magnified image of the bladder and the entire urethra and does not require invasive surgery.


  • Some bladder pathology (ie large bladder stones, tumors, polyps) may need to be removed via laparoscopic-assisted cystoscopy or traditional cystotomy, especially in male dogs Laparoscopy.

Technical Problems

  • Due to narrow diameter of male canine urethra and presence of os penis, urethroscopy is more challenging and is therefore less commonly used in male dogs.


  • Patient size, lack of instrumentation, and lack of expertise.
  • Animals with confirmed diagnosis of a ruptured urinary tract Bladder: trauma rupture.
  • Severe coagulopathy (where tumor ablation or biopsy is contemplated).

Decision Taking

Risk assessment



Veterinarian expertise

  • Ideally been trained on a formal rigid endoscopy course and wet-lab experience.

Nursing expertise

  • Good level of competence required for assisting in procedures, monitoring anesthetic/oxygenation of patient, assisting in sample collection/operating instrumentation, and handling of pathological samples.

Materials Required

Minimum equipment

  • Endoscopic camera system with monitor.
  • Light cable and xenon or metal halide light source.
  • Female:
    • Rigid telescope (superior).
    • 2.7 mm 30 degree oblique 18 cm long telescope with 14.5F cystoscopy sheath with 5F instrument channel (good for animals <30 kg).
    • >30 kg, may be helpful to use larger/longer telescope to reach the bladder ( 3.5 mm-4 mm, 30 degree oblique, 30 cm long telescope) with matching cystoscopy sheath.
    • 30 degree angle of view facilitates complete examination of the trigone by rotation of the teleescope around its long axis.
  • Male:
    • Flexible urethroscope:
      • 2.5-3.9 mm, 70 or 100 cm long fiberoptic scope.
      • Often poor quality images due to few fiberoptic bundles.
      • Small biopsy samples due to size of instrumentation.

Ideal equipment

  • video and still image capture system for patient documentation.
  • Tub table or grid over collecting tray.
  • Drip stand.
  • Equipment for use within operating channel:
    • Biopsy forceps.
    • Grasping forceps.
    • Basket catheters.
    • Injection needles (23G 10 inch).
    • Energy devices for treatments.
      Cystoscopic equipment should be sterilized or disinfected with appropriate solutions as per manufacturers recommendation (eg Med DisTM, Medichem International).

Ideal consumables

  • Giving sets:
    • Attach one to ingress port.
    • Attach one to egress port.
  • 1 liter bags of sterile saline (0.9% NaCl)- warmed.
  • Bucket, towels or incontinence sheets.
  • Water-proof fenestrated drape and towel clamps to help keep area clean from hair/debris.
  • Biopsy cassettes.
  • Pots with sterile saline for initial biopsy collection.
  • Histopathology pots.
  • Bacteriology media for bladder biopsies.



  • Should be chosen according to patients condition.
  • Patient should be allowed to void urine prior to induction of general anesthesia and cystoscopy.

Dietary Preparation

Site Preparation

  • External genitalia of the patient should be clipped and in those breeds with long hair.
  • Cleaned with surgical prep.
  • The tail should be elevated and held out of the operative field with clips and ties.


  • General anesthesia is required.
  • No special anesthetic protocol is universally preferred.
  • Drug selection should be based on animals condition and the expertise of the clinician.

Other Preparation

  • Prior to bladder inspection, urine should be removed - this can be kept for urine analysis and bacteriology prior to the procedure if required.



Step 1 - Procedure in the bitch: position patient

  • Lateral, sternal or dorsal recumbency (hindlimbs extended caudally).
  • Hindquarters positioned at edge of a tub table or grid or absorbant material placed underneath animal:
    • Avoid the animal from getting excessively wet from urine and irrigant.
  • Monitor should be positioned at the head end of the patient directly opposite the surgeon.

Step 2 -

  • Place the rigid telescope within the operating sheath (cystoscopy sheath).
  • Attach camera head to eyepiece of telescope.
  • White balance the camera system.
  • Attach giving set attached to fluid bag onto the ingress port of operating sheath:
    • Flush with sterile saline from the giving set to remove air bubbles from the system.
  • Attach another giving set to egress port on operating sheath.
  • Apply sterile water based lubricant (KY Jelly" Johnson & Johnson) to the shaft of the cystoscopy sheath.

Step 3 -

  • Place the telescope tip within the vulval lips at the dorsal commisure to avoid the clitoral fossa.
  • Point telescope dorsally at an angle of 45 degrees to align with vestibule.
  • Pinch the vulva closed around the operating sheath.
  • Open ingress port.
  • Keep egress port closed until vestibule becomes distended with saline:
    • This helps identify the vaginal os and urethral opening Cystoscopy: vestibule - normal.
  • Perform vaginal examination.
  • Once vaginal examination is completed, withdraw the telescope until the urethral orifice is identified.
  • Carefully advance telescope into urethra to the bladder neck:
    • If using a 30° telescope, maintain the lumen of the urethra at the 6 o'clock position on the screen, assuming the light post is pointing down to prevent damage to the urethral wall.
  • The urethra opens abruptly into the bladder, which is a much larger lumen:
    • Failure to drain urine and replace the fluid with saline will result in poor image quality due to the opacity of urine.
  • Once in bladder, close ingress port and open egress port to allow urine drainage.
  • When bladder collapses around the endoscope, the egress port is closed and the bladder carefully distended.
    Overdistension of bladder may cause mucosal hemorrhage and possibly bladder rupture if the wall is significantly weakened by pathology!
  • If using a 30° telescope, rotate light post to allow examination of the entire circumference of the trigone.

Step 4 -

  • As the bladder distends, examine the dorsal bladder wall at the trigone and identify the two urethral openings (small slits) in approximately the 10 oclock and 2 o'clock position (if animal is in ventral recumbency):
    • Jets of urine can be seen intermittently from the urethral openings.
      It is possible for a urethral opening to be found within the mucosal folds within the urethra (ectopic ureter Ureter: ectopic ); it is important to examine the urethra carefully!

Step 5 -


Digital images/recorded videos should be obtained for medical records and biopsies.

  • Biopsy specimens are obtained from tumors and masses and are best done with the largest cupped biopsy device that can pass through the operating channel.
  • Make sure bladder is quite flaccid as will allow for better biopsy samples.
    Do not biopsy from the center of any ulcerative lesions or areas of severe mucosal damage. This may lead to bladder rupture.
  • Place biopsy samples in pot with sterile saline:
    • Reduces damage to the biopsy forceps and to the sample compared to removing with a needle.
    • Once all biopsy samples are collected, decant the samples:
      • Place some samples into biopsy cassettes and place into formalin pots.
      • Place some samples into media for bacteriology/culture & sensitivity Bacteriology.
  • At the end of the examination, drain the bladder by opening the egress port.
  • Carefully remove cystoscope.

Core Procedure


Step 1 - Transurethral cystoscopy in male dogs

  • Empty and flush the bladder with a urethral catheter prior to examination.
  • Lubricate the insertion tube with sterile water based lubricant (KY Jelly" Johnson & Johnson).
  • Pass the long flexible scope CAREFULLY similar to passing a urethral catheter Urethral catheterization: male :
    • Small urethroscopes are extremely fragile!
    • Manipulation of the urethra and bladder can be helpful whilst urethroscope is being advanced under direct visualization.
    • A syringe filled with saline in addition to standard gravity infusion may help with urethral distension.
    • If pink out, gently withdraw and redirect until the urethral lumen is in the central position, then proceed with examination.

Step 2 - Thoroughly examine the bladder

  • This is easiest if bladder is only mildly distended.
  • Carefully move tip by moving the tip back and forth and 90 degree rotation.
  • Biopsies may be taken with a flexible 1 mm biopsy instrument.
    Do not advance the biopsy instrument through a bent scope as this may damage the lining of the biopsy channel and lead to costly repairs!




  • Mild analgestic narcotic drugs Analgesia: opioid routinely used post transurethral cystoscopy.
  • Nonsteroidal drugs Analgesia: NSAID or tramadol Tramadol may be dispensed.
  • Steroids may be used following dilation of strictures.

Antimicrobial therapy

  • Antibiotics are not routinely used following cystoscopy.
  • Urinary tract infections Cystitis should be addressed based on urine and/or bladder biopsy culture and sensitivity results.
  • On completion of antibiotic course, a cystocentesis Cystocentesis should be obtained for full urinalysis and bacteriology/sensitivity testing approximately 5-7 days post treatment.

Wound Protection

  • None.

Potential complications

  • Penetration of urethra due to excessive force/poor technique.
  • Hemorrhage:
    • Often following biopsies of bladder wall, polyps or transitional cell carcinomas. May also occur due to overdistension of the bladder with irrigant.



  • Depends on condition being investigated/diagnosed.

Follow up

  • Urinary tract disease is frequently progressive, persistent or recurrent and may be due to congenital malformations, urinary calculi, infection, urethral sphincter mechanism incontinence (USMI), or neoplasia.
  • Recurrent urinary tract infections:
    • Every 3-4 months.
    • Cystocentesis sample should be submitted for bacteriology/culture and sensitivity Urinalysis: bacteriology during each visit.
    • Recurrent cystitis may be idiopathic or stress related.
  • Recurrent calculi formation:
    • Stones should be submitted for stone analysis and appropriate treatment instituted.
  • Bladder imaging may be used to monitor disease progression/regression.


Further Reading


Refereed papers

Other sources of information

  • Rawlings C A, Berent A C (2011)Cystoscopy.In: Tams T R, Rawlings C A (eds)Small Animal Endoscopy, St. Louis, Elsevier Mosby.
  • Rawlings C A (2009)Diagnostic Rigid Endoscopy: Otoscopy, Rhinoscopy, and Cystoscopy.Vet Clin North Am Small Anim Pract39, 849-868.
  • Hotston-Moore A, England G (2008)Rigid endoscopy: Urethrocystoscopy and vaginoscopy.In: Lhermette P, Sobel D (eds):BSAVA Manual of Canine and Feline Endoscopy and Endosurgery, Quedgeley, British Small Animal Veterinary Association.