Diseases of nasal passages and paranasal sinuses

what nasal disorders do we see?

• trauma - e.g. lacerations

• facial nerve paresis / paralysis

• nasal atheroma

• alar fold collapse

what is the anatomy of the nares / nostrils?

• alar folds - allows dilating of nostrils

• supported by alar cartilages

• input from facial nerve

• nasal diverticulum

  • false nostril

what are clinical signs of facial nerve paresis / paralysis?

• facial swelling

• asymmetry

• reduced airflow

• nasal stertor

• may get facial distortion

• poor performance

how do we diagnose facial nerve paresis / paralysis?

• observation

• palpation

what side is the paralysis on?

• right hand side of the image (horses left hand side)

• drooping occurring on right side

when do we see facial nerve paresis / paralysis?

• when under GA / recumbent - with pressure over facial nerve

• iatrogenic - e.g. surgery of face

• most often temporary and will resolve with time

what is needed for acute lacerations to the nares?

• for full thickness defects - precise anatomical repair important to persevere ability to dilate fully

• minimal debridement needed - good blood supply and want to preserve tissues

• 2 or 3 layer closure

• monitor for rubbing of sutures

what is the significance of chronic scarring?

• performance limiting - reduced nasal airflow

• cosmesis may be important

• reconstructive surgery possible

what are epidermal inclusion cysts?

cysts within nasal diverticulum (false nostril)

what are clinical signs of epidermal inclusion cysts?

no painful swelling at nasoincisive notch

how do we diagnose epidermal inclusion cysts?

• history

• visual appearance

• histopathology

how do we treat epidermal inclusion cysts?

• surgical removal - under local anaesthetic and standing sedation

• formalin treatment - reported but risk of necrosis so not recommended

what is the prognosis for epidermal inclusion cysts?

• excellent with surgical removal

• likely to recur with simple drainage

what is alar fold collapse?

flaccid or redundant alar folds

what do we see with alar fold collapse?

• respiratory tract noise at exercise

• exercise intolerance in performance horses

how do we diagnose alar fold collapse?

• fluttering sound during exercise (note - DDx = laryngeal / soft palate disorders)

• temporary sutures - see if it makes a difference

how do we treat alar fold collapse?

can resect folds

what are key parts of nasal passage anatomy?

• nasal septum and vomer bone separate nasal passages

• dorsal and ventral conchae (terbinates)

  • thin scrolls of cartilage and bone

  • divide nasal passages into 3 meati - dorsal, middle and ventral

  • form conchal sinuses caudally

• sinus drainage angle

  • narrow passageway where paranasal sinuses drain into nasal passages

  • usually 2-3mm diameter - cannot directly access paranasal sinuses in normal horse with endoscopy

• ethmoidal turbinates

what are congenital disorders of nasal passages?

• wry nose (nasal septum deviation)

• choanal atresia (rare)

what are acquired disorders of the nasal passages?

• trauma

• progressive ethmoid haematoma

• fungal rhinitis

• foreign bodies (rare)

what are clinical signs of disease of nasal passages?

• nasal discharge

• abnormal respiratory noise

• dyspnoea

• malodorous smell

• facial / nasal distortion

• head shaking

• snorting / rubbing nose

what can cause nasal trauma?

• epistaxis

• kick / blunt trauma

• iatrogenic - trauma during nasogastric intubation / endoscopy (common)

how can we avoid iatrogenic trauma?

• ensure tube placement is in the ventral meatus not middle

• use a smooth tube

• lubricant on end of tube

• don’t force the tube when you meet resistance

what are progessive ethmoid haematomas?

• (basically a blood clot)

• encapsulated non-neoplastic mass

• unknown aetiology

• locally invasive - but don’t metastasise

• grows into nasal passages / paranasal sinuses

what are clinical signs of progressive ethmoid haematomas?

• epistaxis - usually intermittent, often slightly brown / red colour

• may get facial swelling

what do these images show?

progressive ethmoid haematoma

how do we diagnose nasal progressive ethmoid haematomas?

• endoscopy - characteristic yellow / green lesion on ethmoid

• can use computed tomography

how do we diagnose sinus progressive ethmoid haematomas?

• radiography

• sinoscopy

• computed tomography - to assess cribriform plate

  • often bilateral so check both sides

how do we treat nasal progressive ethmoid haematomas?

• intra-lesional formalin

  • need to CT first to assess the cribiform plate

  • multiple formaline injections

• laser excision / ablation

  • can be done if it is small

  • can be done post formalin treatment

how do we treat sinus progressive ethmoid haematomas?

sinus flap surgery

• treat sinusitis

• remove lesions - can use laser

what is fungal rhinitis due to?

• can be primary - but uncommon in UK

• secondary - fungal disease secondary to bacterial sinusitis

what are clinical signs of fungal rhinitis?

• unilateral purulent / haemorrhagic nasal discharge

• malodorous smell

• occasionally nasal stertor

how do we diagnose fungal rhinitis?

• endoscopy

• fungal culture

how do we treat fungal rhinitis?

• removal of fungal plaques and necrotic bone

• topical anti-fungal treatment - e.g. enilconazole lavage

what are the two groups of paranasal sinuses?

• rostral group

• caudal group

• sinuses within each group share drainage into nasal passages

• note - no communication between groups - separated by oblique bony septum

what sinuses are in the rostral group of paranasal sinuses?

• rostral maxillary

• ventral conchal

what sinuses are in the caudal group of paranasal sinuses?

• caudal maxillary

• frontal

• dorsal conchal

• sphenopalatine

• ethmoid sinus

why is the proximity of nasal sinuses to other structures significant?

• can cause disease in close structures - e.g. intrasinus PEH can extend into the brain

• diseases may extend from these structures to the nasal sinuses - e.g. periapical regions of the teeth can lead to secondary sinusitis

what disease of the paranasal sinus do we see?

• primary sinusitis

• secondary sinusitis - due to fungal or periapical infection

• sinus cysts

• sinus PEH

• neoplasia

• trauma

what clinical signs are common for paranasal sinus diseases?

• nasal discharge - usually unilateral

  • serous, purulent, mucopurulent or haemorrhagic

• may get facial swelling, facial deformity or decreased nasal airflow

how do we diagnose paranasal sinus disease?

• using history, clinical signs, physical examination, and external examination of the head - lymph nodes, facial symmetry, nasal airflow, percussion of sinuses

• endoscopy

  • can see sinus drainage angle

• radiography

  • laterolateral or dorsoventral

• computed tomography

• sinoscopy

when do we usually see primary sinusitis?

• 40% of cases are primary

• occurs often with previous URT infection

• most common cause - Streptococcus spp

when treating secondary sinusitis, what should we consider?

need to treat sinusitis and the primary cause, e.g:

• dental disease

• sinus cyst

• PEH

• neoplasia

• fungal sinusitis

how would we diagnose sinusitis on endoscopy?

visualise purulent material coming from sinus drainage angle

how would we diagnose sinusitis by radiography?

• fluid lines on lateral views

• increases radiodensity in sinuses on dorsoventral views

• (poor sensitivity for identifying cause of secondary sinusitis)

what are advantages of computed tomography for diagnosis of sinusitis?

• allows differentiation of primary vs secondary sinusitis

• has greater sensitivity when imaging the teeth

• useful for pre-operative planning

how would we treat primary sinusitis?

• antimicrobials - one course only (poor response indicates further investigation required)

  • do culture and sensitivity testing to rule out Strep. equi var equi infection (strangles)

• NSAIDs - e.g. phenylbutazone

• feed from ground to encourage drainage

• dust free management - reduce YRT inflammation

• turn out as much as possible - encourage drainage and reduce inflammation

• surgical drainage may be required in cases that don’t respond to other treatments

how do we treat secondary sinusitis due to dental disease?

• removal of infected tooth

• management of sinusitis

how do we diagnose secondary sinusitis due to dental disease?

• computed tomography gold standard

• computed tomography is difficult to interpret

what are paranasal sinus cysts?

• uncommon

• seen in young horses most commonly

• aetiology is unknown

• cysts filled with yellow, viscous fluid

• causes erosion and distortion as it expands

  • nasal passage deformity

  • facial swelling

what are clinical signs of paranasal sinus cysts?

how do we diagnose paranasal sinus cysts?

how do we treat paranasal sinus cysts?

what common types of sinus neoplasia do we see?

what are clinical signs of sinus neoplasia?

how do we diagnose sinus neoplasia?

how do we treat sinus neoplasia?

how do we diagnose sinus trauma?

how do we treat sinus trauma?

what are advantages of sinoscopy for nasal sinuses?

how do we perform sinus surgery - sinus flaps?

what are potential complications of sinus surgery?

what is empyaemia of conchal bullae?

chronic infection of dorsal or ventral conchal bulla

• surgical techniques for drainage of bullae

what is suturitis?