Lecture 33: EQUINE disease of nasal passages and paranasal sinuses

- dry MM (cold weather)

- exertion

- ethmoid hematoma

- nasal polyps

- guttural pouch mycosis

- neoplasia

What are the causes of unilateral epistaxis?

- EIPH

- head trauma

- clotting disorder

- severe pleuropneumonia

What are the causes of bilateral epistaxis?

- cartilaginous support over nasoincisive notch

- the first major site of upper airway resistance

What is the importance of this external nares or a false nostril in the horses nose?

- cyst in false nostril

- cause is unknown

What is atheroma or epidermal inclusion cyst?

- mass (3-5 cm) spherical nodule

- FNA + cytology if indicated

How do you diagnose atheroma or epidermal inclusion cyst?

- surgical removal

How do you treat atheroma or epidermal inclusion cyst?

- excellent --> no recurrence reported

What is the prognosis for atheroma or epidermal inclusion cyst?

- trauma

- inflammation

- infection (abscess or granuloma)

- neoplasia

- congenital = wry nose

What are etiologies of general problems of the nasal passage even though uncommon?

- clinical signs: RR noise, decreased airflow, nasal discharge, facial deformity

- rads: DV = best

- CT

How can you diagnose problems with the nasal spetum?

true

- can do but less helpful to see the rostral portion of the nasal passage

True or false

endoscopy is not helpful with diagnosing issues with the nasal septum

- resection of the septum

- must leave the rostral section to prevent collapse

How do you treat problems with the nasal septum?

- pedunculated growths from the mucosa of the nasal cavity, septum, ect

- treated with surgical excision

What are nasal polyps? How are they treated?

- inspiratory dyspnea

- nasal discharge

- odor

What are the clinical signs seen with nasal polyps?

- slowly expanding non-neoplastic mass

- originates from submucosa of ethmoid labyrinth or paranasal sinuses

- can expand down the nasal passages +/- into the sinuses

What is progressive ethmoid hematoma?

- unilateral serosanguinous nasal discharge

- respiratory noise and dyspnea = if large enough

- head shaking

- halitosis

- facial deformity = less common

What are the clinical signs seen with progressive ethmoid hematoma?

- clinical signs --> unilateral serosanguinous nasal discharge

- endoscopy --> smooth greenish-yellow to purple-red mass (+/- fungal plaques

- radiographs --> will see it

How do you diagnose progressive ethmoid hematoma?

- surgical excision (mass removal + destruction of origin)

- transendoscopic (laser or intra-lesional formalin inj)

How can you treat a progressive ethmoid hematoma?

- concho frontal sinus = blue

- rostral maxillary sinus = yellow

- caudal maxillary sinus = orange

What are these equine structures?

- all compartments communicate directly or indirectly

- all will eventually drain together through the nasomaxillary opening

What is important to know about the paranasal sinuses?

- Primary = often following and URT infection especially if strep sp.

- Secondary = tooth abscess, trauma (facial fracture), neoplasia

What are the primary and secondary etiologies for sinusitis?

- unilateral nasal discharge = Most common

.....- Odor - often a root tooth abscess

.....- Purulent

- +/- epiphora, conjunctivitis, enlarged submandibular LNs, respiratory noise

What are the clinical signs seen with sinutsitis?

- sinuses

- nasal cavity

Where might the fluid be from with unilateral discharge?

- guttural pouches

- nasopharynx

- lungs

- bilateral paranasal sinus disease ( primary sinusitis)

Where might the fluid be from with bilateral discharge?

- radiographs= see opacity in sinuses and fluid lines

- endoscopy= pus from nasomaxillary opening, BUT can't see into sinus

- sinocentits - cytology + culture (can LAVAGE at the same time)

- sinoscopy - visualization of sinus, minimally invasive

- CT - complicated cases

How do you diagnose sinusitis?

- primary: abx and lavage

- secondary: treat secondary issue

- failure is common = warn client

How do you treat sinusitis? What should you warn the O about?

- inspissated pus (ventral conchal sinus)

- failure to treat the primary problem

- fungal infection

- neoplasia

Why does sinusitis treatment often fail?

- has an unknown etiology

- fluid filled structures lined by epithelium and will deform the bone --> facial deformation

What is a sinus cysts?

- facial deformities

- unilateral mucoserous nasal discharge

- reduced airflow on affected side

- NO ODOR since no bacterial involved

What are the clinical signs seen with sinus cysts?

- RADS (CT and MRI)

- remove since will recur if you do not remove the lining

- good prognosis if fully removed

How do you diagnose and treat sinus cysts? What is the prognosis?

- squamous cell carcinoma

What is the most common sinus neoplasia?

- typically malignant and invasive

- nasal discharge, facial deformities, loose teeth and epiphora (tearing)

What are sinus neoplasia like in horses?

- aspirate fluid for cytology or biopsy

- surgical margins hard to get --> euthanasia

How do you diagnose and treat sinus neoplasias?

- synoscopy with a scope

- sinus flaps where you open the sinuses

How can you do surgeries on the sinus?

- standing or under GA

- cutting 3 of edges and break the 4th to hinge it open

- use a mallet and osteotome or oscillating saw

- bevel the flap

How do you create a bone flap for sinus surgery?

- make a large opening into the nasal cavity to facilitate drainage

- post-op levage may be needed

- pack the sinus post op --> controls hemorrhage

What are considerations for surgery of the sinuses?

- hemorrhage --> especially ethmoid hematoma

- recurrence

- failure to resolve clinical signs

What are complications for surgery of the sinuses?