Sinusitis and Its Complications
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Direct answer
Sinusitis is inflammation of the paranasal sinus mucosa, nearly always following a viral or allergic process that obstructs the sinus ostium; it is acute when symptoms last under four weeks and chronic beyond twelve weeks. The maxillary sinus is affected most often because its ostium sits high and its floor lies near the tooth roots. Although most acute episodes settle medically, spread beyond the sinus produces orbital cellulitis, cavernous sinus thrombosis, osteomyelitis and intracranial infection, which are ENT emergencies.
What you must remember
- Predisposition: any cause of ostial obstruction — upper respiratory infection, allergic rhinitis, deviated septum, polyps, dental infection and diving or flight barotrauma.
- Acute sinusitis: pain and tenderness over the affected sinus, worse on bending forward, nasal obstruction and purulent discharge; frontal sinusitis strikes older children and young adults with headache worse on lying down, and maxillary sinusitis often follows dental sepsis.
- Chronic rhinosinusitis: nasal obstruction, mucopurulent discharge, postnasal drip and hyposmia persisting beyond twelve weeks, with mucosal changes on endoscopy and computed tomography.
- Orbital complications: periorbital cellulitis and orbital cellulitis or abscess, usually from ethmoiditis in children — proptosis, chemosis, painful eye movements and visual loss demand urgent treatment.
- Cavernous sinus thrombosis: infection tracks through the valveless angular and ophthalmic veins in the "danger area of the face", producing proptosis, chemosis, severe pain and palsies of the third, fourth, sixth and ophthalmic division of the fifth nerve, often becoming bilateral.
- Other complications: frontal osteomyelitis with subperiosteal abscess (Pott's puffy tumour), meningitis, and frontal lobe brain abscess.
- Management: acute disease responds to nasal decongestants, saline irrigation, analgesia and antibiotics when bacterial; chronic disease needs intranasal steroids and saline irrigation, with functional endoscopic sinus surgery (FESS) to restore ostial drainage when medical therapy fails; complications need intravenous antibiotics, imaging and combined surgical drainage.
Common confusion
Do not label every congested nose as sinusitis — the diagnosis needs facial pain with nasal obstruction and discharge, not congestion alone. Also distinguish the tender, swollen cheek of maxillary sinusitis of dental origin from dental pain itself, and remember that periorbital oedema in a child with fever is orbital cellulitis until proved otherwise, needing admission rather than outpatient drops.
Exam-focused takeaway
For theory, classify by duration and sinus, list causes of ostial obstruction, describe acute and chronic disease and then the complications — cavernous sinus thrombosis and Pott's puffy tumour carry assured marks. In viva, expect the reason the maxillary sinus is commonest, the danger area of the face and the indications for FESS. In the posting, learn anterior rhinoscopy and endoscopy to see pus in the middle meatus, the single physical sign that anchors the diagnosis.
Frequently asked questions
Which sinus is most commonly involved?
The maxillary sinus, because its ostium is placed high on its medial wall, drainage is against gravity, and its floor is related to the tooth roots.
What is the danger area of the face?
The area around the nose and upper lip drained by the angular vein, which communicates with the cavernous sinus through the ophthalmic veins, allowing facial infection to become intracranial.
What are the features of cavernous sinus thrombosis?
Proptosis, chemosis, painful ophthalmoplegia with third, fourth and sixth nerve palsies, trigeminal hypoaesthesia, fever and often bilateral spread.
What is Pott's puffy tumour?
Frontal osteomyelitis with subperiosteal abscess presenting as a swollen, doughy forehead, classically following frontal sinusitis.
When is surgery indicated in sinusitis?
Failure of adequate medical therapy in chronic rhinosinusitis, persistent polyps or anatomical obstruction, and any suppurative complication — the modern operation being functional endoscopic sinus surgery.
How is chronic sinusitis treated medically?
Intranasal corticosteroid spray with saline irrigation, treatment of allergy and dental sepsis, and short antibiotic courses for exacerbations.