Paranasal sinuses Flashcards
What are paranasal sinuses? What lines them?
Air filled cavities in the bones around the nose in continuity with the nasal cavity.
Frontal, maxillary, ethmoid, sphenoid
Lined by ciliated mucosa which sweep debris and mucus towards and through the osteomeatal complex into the nostrils.
Obstruction impairs drainage:
Anatomy (septal deviation, polyps) or mucosal problems (viral infection causing mucosal oedema
Where does the maxillary sinus drama?
Middle meatus (below middle concha on lateral nasal wall)
Where does the ethmoidal sinus drain?
Anterior ethmoidal –> middle meatus
Middle ethmoidal –> middle meatus
Posterior ethmoidal –> superior meatus
Where does the sphenoid sinus drain?
Sphene-Ethmoidal recess above superior meatus on superior turbinate/concha
Where does the frontal sinus drain?
Middle meatus
Where does the nasolacrimal duct drain?
Inferior meatus
What is acute bacterial rhinosinusitis?
Inflammation of the mucous membranes of the paranasal sinus due to infection
3 of:
Discoloured discharge (with unilateral predominance) and purulent secretion in the nasal cavity
Severe local pain (with unilateral predominance)
Fever (>38)
Raised ESR/CRP
Double sickening - deterioration after an initial milder illness
What are causes of bacterial sinusitis?/predisposing factors?
Most follow viral infection
Direct spread from dental root infection or diving/swimming in infected water
Odd anatomy: septal deviation, nasal polyps, large uncinate process (part of ethmoid bone forming maxillary sinus medial wall)
ITU causes: mechanical ventilation, NG tubes
Systemic causes: immunodeficiency
Biofilms: infection which destroy mucosal cells of cilia and goblet cells
What are common organisms in acute sinusitis?
Strep pneumoniae
Haemophilus influenza
Staph aureus
Moraxhella catarrhalis
Rhinovirus
What are the features of sinusitis?
Facial pain: typically frontal pressure pain which is worse on bending forward
Nasal discharge: thick and purulent
Nasal obstruction: e.g. mouth breathing
Post-nasal drip: may produce chronic cough
What investigations in sinusitis?
Clinical diagnosis
Examin nose and look for mucosal inflammation, oedema, discharge, polyps and septal aviation
CT paranasal sinuses and naasal endoscopy helps confirm in recurrent/chronic sinusitis
What is management of acute sinusitis?
Analgesia
Nasal saline irrigation
Intra-nasal decongestants
Oral antibiotics if bacterial infection suspected: phenoxymethylpenicillin, co-amoxiclav if systemically unwell
What is management of recurrent sinusitis?
Analgesia
Refer to ENT for imaging/surgery
smoking cessation as tobacco irritates nasal mucosa and reduces collar fucniton
Intranasal corticosteroids
What are complications of sinusitis?
Orbital cellulitis/abscess
Intracranial involvement: meningitis, encephalitis, cerebral abscess, cavernous sinus thrombosis
Mucocoeles may become infected
Osteomyelitis: classically staph e.g. frontal bone
When should you suspect paranasal sinus cancer? Where are early signs?
Investigations? Management?
Chronic sinusitis present for the first time in later life
Blood-stained nasal discharge and nasal obstruction, cheek swelling
MRI
CT ± endoscopy with biopsy
Radiotherpay
± radical surgery
