Nasal planum and nasal cavity Flashcards
What technique for treatment of stenotic nares was described by Dickerson 2020 in Vet Surg?
Dorsal offset rhinoplasty
In a study by Clarke 2022 in Vet Surg, did surgical correction of BOAS improve the reduction in dorsoventral diameter of the nasopharynx during respiration?
No - surgery did not improve the reduction in dorsoventral diameter of the nasopharynx. May suggest inadequate upper airway dilator muscle function.
According to Gleason 2022 in Vet Surg, list 4 respiratory and 3 gastrointestinal abnormalities that are more common in brachycephalic cats.
Increased dyspnea, sneezing, coughing, nasal discharge, respiratory noise, decreased activity.
Increased halitosis, difficulty chewing and hypersalivation.
Compare to Gleason 2023 in Vet Surg, with improvements in these parameters observed following ala vestibuloplasty - specifically improved pulmonary blood flow (decreased pulmonary transit time), decreased snoring, open mouth breathing, sneezing, dyspnoea, nasal discharge, increased activity.
According to Franklin 2024 in Vet Surg, which of the following rhinoplasty techniques resulted in the greatest increase in the cross sectional area of the nares and nasal vestibuli?
1) Vertical wedge resection
2) Modified horizontal wedge resection
3) Ala-vestibuloplasty
Ala-vestibuloplasty resulted in greatest increase (74%, as compared to 26% for vertical wedge, and 15% for modified horizontal wedge).
Ala-vestibulopasty also extended further caudally (to the level of the caudal nasal vestibule).
In a study by Bouyssou 2021 in JFMIS, what CT findings were characteristic of non-lymphomatous nasal neoplasia?
More likely to be unilateral, extend into the frontal sinus, and show areas of mineralization. Regional lymphadenomegaly was more common in lymphoma.
Overlap between CT findings of neoplastic and inflammatory conditions, but bony changes to the nasal cavity boundaries less likely with inflammatory lesions.
In a study by Yoshikawa 2023 in JVIM, what was the MST for sinonasal tumours undergoing stereotactic radiotherapy? What complications were reported (2)?
MST 441 days.
Oro-nasal or naso-cutaneous fistula (7%), and chronic rhinitis (61%).
Describe the cartilages of the nose.
Name the nasal conchae of the nasal cavity.
Ventral, dorsal, ethmoidal. Ventral is larger than the dorsal conchae and the rostral extension forms the alar fold.
Name the nasal meatuses of the nasal cavity.
Ventral, middle, dorsal and common.
What is the rostral extent of the nasopharynx?
The choanae.
What are the three paranasal sinuses?
Maxillary recess, sphenoidal sinus, frontal sinus.
The anatomy of the frontal and sphenoidal sinuses vary, and they may be absent in some patients.
What are the major differential diagnoses for dogs or cats with nasal disease?
Neoplasia (adenocarcinoma, SCC, lymphoma, other), inflammatory polyp, fungal infection, viral infection, bacterial infection, foreign body, dental disease, idiopathic rhinosinusitis, nasal mites, ciliary dyskinesia.
What imaging techniques can be used for the work-up of nasal/nasopharyngeal disease?
Radiography: bone lysis associated with the presence of neoplastic disease.
CT/MRI: allow more detailed information than radiography, and may be better able to differentiate neoplasia from rhinitis.
Rhinoscopy/nasopharyngoscopy: allows for simultaneous exploration and sample collection. Samples can be collected by swab, flush or biopsy. Severity of mucosal abnormalities are not necessarily predictive of histopathologic abnormalities.
What is the CT appearance of nasopharyngeal polyps?
Isoattenuating to the surrounding muscle, and hypoattenuating to the adjacent soft tissue. Contrast rim enhancement is common.
What test might be useful in diagnosing cryptococcus infection in cats?
Serum antigen testing. May eliminate the need for invasive testing.
What test can be used to detect Mycoplasma and Bartonella bacterial species as possible causes of rhinitis?
PCR testing. Routine culture swabs of the nasal passages are rarely informative.
What is the most common neoplasm of the nasal planum?
SCC (cats more commonly affected than dogs).
White cats at increased risk for development.
What is the MST for dogs undergoing surgical excision of nasal planum SCC?
12.5 weeks (with surgery alone). 26 weeks was reported with the use of radiotherapy alone.
What is the cause of stenotic nares in brachycephalic dogs?
Axial deviation of the dorsolateral nasal cartilage.
Abnormal conchal development is also common, with frequent extension into the nasopharynx.
What is the most common nasal neoplasm in the cat?
Lymphoma (MST 98 days with chemotherapy).
What is the most common nasal neoplasm in the dog?
Adenocarcinoma. Medium to large breed dogs are overrepresented.
What is the treatment of choice for intranasal neoplasia in dogs?
Radiation (surgery has not been shown to improve survival). MST 8-19 months. Dogs with invasion of the cribiform plate have shorter survival times.
What are the most common fungal diseases of the nose in dogs and cats?
Dogs: aspergillus fumigatus, blastomyces dermatidis, pythium.
Cats: cryptococcus.
What dogs are typically affected by fungal nasal disease?
Young, large breed dogs. Causes a destructive rhinitis that is difficult to distinguish from nasal neoplasia.
What are treatment options for fungal rhinosinusitis?
- Trephination and infusion of low dose enilconazole daily for 7-10 days, or single high dose of clotrimazole.
- Noninvasive foley catheter technique. Proposed to provide better distribution of infusate (with trephination medications often don’t reach the rostral frontal sinus if the septum between the rostral and lateral portions of the sinus are intact).
- Open rhinotomy and use of povidine iodine packing or enilconazole lavage. Typically reserved for refractory cases.
What percentage of dogs are cured with surgical or non-invasive infusion catheter treatment of fungal infections?
65% with a single treatment, 87% with up to four infusions.
What are some differentials for dogs/cats with nasopharyngeal disease?
Neoplasia, foreign bodies, inflammatory polyps, fungal granulomas, cysts, choanal atresia or nasopharyngeal stenosis.
What are nasopharyngeal polyps?
Benign lesions arising from the mucosa of the auditory tube, middle ear, or nasopharynx. More common in cats.
What is the cause of nasopharyngeal polyps?
Unknown - congenital and infectious (calicivirus, herpesvirus) have been postulated.
What are treatment options for nasopharyngeal polyps?
Traction avulsion +/- glucocorticoids, removal via VBO.
Traction avulsion may result in Horner’s syndrome or vestibular signs.
How is choanal atresia diagnosed?
Endoscopy, positive contrast rhinography, CT/MRI.
Can be complete obstruction or partial (membranous or osseous).
What is the treatment of choanal atresia?
Balloon dilatation or open excision and choanal reconstruction.
What are some causes of nasopharyngeal stenosis?
Most often acquired rather than congenital. Secondary to surgery, trauma, or upper airway infection.
What are treatment options for nasopharyngeal stenosis?
- Balloon dilatation.
- Surgical excision (requires accurate mucosal apposition to prevent recurrence).
- Stenting.
What arteries will be encountered during nasal planectomy?
Dorsal and lateral nasal arteries, and major palatine arteries.
Which bones are transected during nasal planectomy?
Incisive bones, rostral aspect of the maxilla and nasal bones.
What is the Trader’s technique for stenotic nare correction?
Amputation of the ventral portion of the dorsolateral nasal cartilage and its associated epithelium.
What types of wedge resection can be performed for correction of stenotic nares?
Vertical, horizontal, lateral. Wedges are removed from the dorsolateral nasal cartilage.
What is an alarpexy procedure?
Permanent fixation of the wing of the nostril to the adjacent skin, resulting in abaxial displacement of the wing of the nostril.
More invasive than other described techniques and usually reserved from revision surgeries.
What treatment technique can be used for management of aberrant nasal conchae?
Laser assisted turbinectomy (LATE) using a diode laser.
A reduction in intranasal airway resistance of 50% has been observed in dogs following this approach, but regrowth the turbinates has been observed.
Why should bilateral carotid artery occlusion be avoided in cats?
Less robust cerebral blood supply and lack of an internal carotid artery increase the risk of brain ischemic damage.
What are the surgical approaches that can be used to access the nasal cavity?
Dorsal: nasal cavity and sinuses.
Ventral: ventral nasal cavity, nasopharynx, ethmoid turbinates.
Lateral: unilateral exposure.
Rostral/alveolar mucosal: rostral aspect of the nasal cavity.
Why should ventral approaches to the nasal cavity be performed in caution in cats?
Prolonged maximal opening of the mouth can result in maxillary artery compression and subsequent cerebral and retinal ischemia.
Describe the dorsal approach to the nasal cavity.
Note: If the bone flap is diseased, previously irradiated, or unstable after fixation it can be removed instead of replaced.
What is nasal extirpation or extenteration?
Complete removal of the intranasal structures. The ethmoid turbinates are generally not removed due to concerns of hemorrhage and accidental intracranial penetration.
Describe the ventral approach to the nasopharynx.
Incision through the oral mucosa, palatinus muscle and nasopharyngeal mucosa. Caudal margin of the soft palate is left intact.
Layers closed separately in 3 layers.
Describe the ventral approach to the nasal cavity.
What are the potential advantages of a ventral rather than dorsal approach to the nasal cavity?
Improved cosmesis, lower risk of subcutaneous emphysema, less postoperative pain, more rapid recovery.
Potential disadvantage is the risk of oronasal fistula formation.
Why should ventral rhinotomy be performed with caution in young animals?
Damage to the vomer bone can cause altered muzzle growth in dogs, and can retard transverse palatal length in cats.
What are some potential complications following rhinotomy?
Aspiration, hemorrhage (can be reduced by packing the nasal cavity with umbilical tape or gauze and removing 24 hours after surgery), subcutaneous emphysema, chronic serous nasal discharge following removal of the turbinates, postoperative infection (uncommon).
How can subcutaneous emphysema be minimized following rhinotomy?
Minimizing subcutaneous dissection, establishing a secure periosteal closure, leaving a gap at the caudal aspect of the incision, adequate post-operative analgesia and sedation to prevent vocalization and excessive movement.
How should the ideal location for sinusotomy be determined?
Based off preoperative imaging, as the location and size of the sinuses might vary based on sex, breed and ongoing pathology.
Generally performed in conjunction with a dorsal rhinotomy.
