Contributors: Kathleen P Freeman, Elizabeth Rozanski

 Species: Canine   |   Classification: Techniques

Introduction Requirements Preparation Procedure Aftercare Outcomes Further Reading




  • Well-tolerated.
  • May be curative if foreign object present.
  • Biopsy sample may be readily obtained.


  • Tendency for hemorrhage.
  • Deep planes of anesthesia required for evaluation of nasopharynx.
  • Further therapy indicated if mass or fungal infection identified:
    • Surgery.
    • Radiation therapy.
    • Infusion of anti-fungals.
  • Relatively expensive equipment.

Alternative Techniques

  • Radiography.
  • CT imaging.
  • Blind flushing or biopsy.

Time Required


  • 10-15 minutes for induction of anesthesia.
    To avert aspiration of blood use cuffed endotracheal tube for general anesthesia Tracheostomy 02: inflatable cuffed tube.


  • 10-15 minutes for procedure
    Perform radiographs or CT prior to rhinoscopy.

Decision Taking

Criteria for choosing test

Risk assessment

  • Low risk for the patient from the procedure.
  • Some risk of hemorrhage, which at times may be dramatic.
  • Older patients may have systemic disease.



Veterinarian expertise

  • Medium.

Anesthetist expertise

  • Medium.
  • Dog needs to be deep enough to tolerate the procedure but high risk of hemorrhage.

Nursing expertise

  • Medium
  • Relatively straight-forward procedure.
  • Equipment cleaning may be complex.

Materials Required

Minimum equipment

  • May be performed with a an otoscopic cone and light source in some cases.
  • Additionally, the caudal nasal cavity may be viewed with a spay hook to retract the palate, dental mirror and light source.

Ideal equipment

  • Rigid or flexible endoscope of small diameter is optimum.
  • Flexible endoscope may be retroflexed behind the soft palate to permit inspection of the caudal nasopharynx.

Ideal consumables

  • Standard equipment for care and cleaning of endoscopy.



  • None required

Dietary Preparation

  • Nothing per os for 8-12 hours prior to anesthesia.


  • General anesthesia with endotracheal intubation Endotracheal intubation.
  • Nasopharynx, very sensitive to stimulation; potential for aspiration of blood and other fluids exists.



Step 1 -

  • Induce general anesthesia using standard techniques General anesthesia: overview.
  • Perform complete oral examination, including laryngeal examination if indicated.

Step 2 -

  • Perform diagnostic imaging as clinically indicated/available.
    Skull radiographs, and/or CT or MRI scanning are very beneficial.

Core Procedure

Step 1 -

  • Place patient in sternal recumbency with nose positioned over the table.

Step 2 -

  • Place a receptacle on the floor underneath nose to collect hemorrhage.

Step 3 -

  • Inspect external nasal passages and feel for asymmetry.
  • Palpate regional lymph nodes.

Step 4 -

  • Examine posterior nasal cavity using either a dental mirror and spay hook or by retroflexing the endoscope.
    Anesthesia should be very deep to prevent patient struggling or reflexes.
  • Document and biopsy any masses visualized.
  • Nasal washing Nasal flushing may be less sensitive than biopsy Biopsy: nasal.
  • Endoscopic brushing specimen may be taken from focal lesions for cytologic evaluation.

Step 5 -

  • Examine both nasal passages from an anterior approach.
  • Evaluate:
    • Mucosa.
    • Secretions (if present).
    • Presence of fungal plaques  or foreign bodies.
    • Turbinates and ability to enter sinuses.
    • Presence of masses.
  • Biopsy abnormal regions Biopsy: nasal.


Step 1 -

  • Remove endoscope carefully.
  • Request assistant to clean endoscope.

Step 2 -

  • Control hemorrhage as needed.
  • Can infuse dilute phenylephrine Phenylephrine into nasal cavity to help trigger vasoconstriction.
  • Can place ice packs on nasal passage.
  • In rare cases with severe hemorrhage, ligation of the ipsilateral carotid artery may be necessary to stop bleeding.




  • Monitor for hemorrhage or difficulty in breathing during recovery from anesthesia.

Fluid requirements


  • Usually not required.

Antimicrobial therapy

  • Rarely required.
  • Secondary bacterial infections may occur.

Other medication

  • Other therapy as directed by rhinoscopy and biopsy results.

Potential complications

  • Hemorrhage is the most common; generally responds to standard methods of control.
    In very rare cases, an overzealous endoscopist could enter into the brain in a dog with a nasal tumor entering the brain.



  • As directed by underlying disease.

Follow up

  • As directed by underlying disease.



  • Hemorrhage.
  • Failure to get diagnostic sample.


  • Dependant upon underlying disease.

Reasons for Treatment Failure

  • Operator difficulty.
  • Dog size or bleeding causing inadequate viewing of nasal passages.

Further Reading


Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Harcourt-Brown N (2006) Rhinoscopy in the dog 1. Anatomy and techniques. In Practice 28 (4), 170-175 VetMedResource.
  • Harcourt-Brown N (2006) Rhinoscopy in the dog 2. Conditions associated with chronic nasal discharge. In Practice 28 (5), 238-246 VetMedResource.
  • Noone K E (2001) Rhinoscopy, pharyngoscopy, and laryngoscopy. Vet Clin North Am Small Anim Pract 31 (4), 671-689 PubMed.
  • Lent S E & Hawkins E C (1992) Evaluation of rhinoscopy and rhinoscopy-assisted mucosal biopsy in the diagnosis of nasal disease in dogs: 119 cases (1985-1989). J Am Vet Med Assoc 201 (9) 1425-1429 PubMed.