Chronic sinusitis
Chronic sinusitis — also called chronic rhinosinusitis (CRS) — is one of the most prevalent chronic conditions in the population and one of the most common reasons for referral to an ENT specialist. It is also frequently misdiagnosed: many symptoms attributed to sinusitis have other causes, and treating sinusitis that is not actually present produces no benefit. Accurate diagnosis is the starting point, and it requires more than a patient’s report of “sinus pain.”
Diagnosis — What Chronic Sinusitis Actually Is
Chronic sinusitis is defined by the presence of two or more of the following symptoms for twelve weeks or longer: mucopurulent nasal discharge (from the nose or draining into the throat), nasal obstruction, reduced or absent sense of smell, and facial pain or pressure. Symptoms alone are not sufficient — the diagnosis also requires objective evidence of sinus inflammation, either on CT scan or on direct endoscopic examination showing pus draining from the sinus openings.
This definition matters clinically. Nasal obstruction alone, post-nasal drip alone, facial pain alone, or loss of smell alone are each individually rarely caused by sinusitis. The combination of two or more of these symptoms with imaging or endoscopic evidence is required for the diagnosis. Patients who present with isolated facial pain or headaches — particularly unilateral episodic headaches — without other sinus symptoms are more likely to have migraine or another primary headache disorder than sinusitis, regardless of what a CT scan may appear to show.
Chronic sinusitis is divided into two broad categories: CRS with nasal polyps and CRS without nasal polyps. These have different underlying pathophysiology, different natural histories, and different treatment approaches.
Differential Diagnoses — What Else Causes These Symptoms
Before treating for chronic sinusitis, it is worth considering whether each symptom may have an alternative explanation.
Nasal obstruction in the absence of other sinus symptoms is more commonly caused by a deviated nasal septum, inferior turbinate hypertrophy, allergic rhinitis, adenoid enlargement, or nasal valve collapse. Nasal valve collapse in particular is frequently missed — it produces nasal obstruction that worsens on inspiration and is not improved by medical sinusitis treatment.
Post-nasal drip — the sensation of mucus draining into the throat — can be caused by gastro-oesophageal reflux, laryngopharyngeal reflux, allergic rhinitis, vasomotor rhinitis, or simply a throat clearing habit. Not all post-nasal drip originates from the sinuses.
Facial pain and headaches around the eyes or forehead are very commonly attributed to sinuses by patients but are rarely caused by sinusitis unless other nasal symptoms are also present. Episodic periorbital or frontal headaches are more likely to represent migraine. A CT scan during a headache episode can be helpful in ruling out sinus pathology when the diagnosis is genuinely uncertain.
Loss of smell (anosmia) has many causes beyond sinusitis — including post-viral anosmia, medications, neurological conditions including Parkinson’s disease, and age-related decline. Progressive or sudden loss of smell warrants thorough assessment before attributing it to sinusitis.
Medical Management
Once the diagnosis is confirmed, the first-line treatment for chronic sinusitis is maximal medical management — a sustained trial of appropriate medical therapy before surgical intervention is considered. This typically involves high-volume saline irrigation of the nasal passages (using a large-volume delivery bottle such as NeilMed or Flo), a regular intranasal corticosteroid spray, and where polyps are present, a course of oral corticosteroids may be appropriate. Underlying allergy should be identified and managed — allergy testing and immunotherapy can significantly reduce the inflammatory burden driving recurrent sinus disease.
Medical management must be used consistently for a sufficient duration — patients who use a nasal spray intermittently or abandon treatment after two weeks are not giving the therapy a proper trial. Compliance with saline irrigation in particular is important; it physically clears debris and inflammatory mediators from the sinus openings and is a meaningful part of treatment, not merely a supplementary suggestion.
Patients who do not respond to adequate medical management, or who have recurrent exacerbations despite ongoing treatment, may be appropriate candidates for surgical intervention.
Surgical Treatment — Functional Endoscopic Sinus Surgery (FESS)
Functional endoscopic sinus surgery (FESS) addresses the structural factors that impair sinus drainage and ventilation. Using a fine telescope passed through the nostril under general anaesthesia, the sinus openings are widened, obstructing tissue is removed, and any polyps are cleared. The procedure does not involve any external incisions. It is performed as a day procedure or with a single overnight stay.
FESS does not cure the underlying inflammatory condition — in patients with CRS with polyps in particular, the polyps tend to recur over time and ongoing medical management is required after surgery. Surgery improves drainage and allows medical treatment to reach the sinuses more effectively, but it is part of an ongoing management strategy rather than a definitive cure.
In children, removal of the adenoids is an important component of managing chronic or recurrent rhinosinusitis, as adenoiditis can contribute significantly to sinus drainage problems, particularly in children under five.
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Dr Roth’s Clinical Perspective
The most important clinical skill in managing chronic sinusitis is knowing when it is not sinusitis. A large proportion of patients referred to me with a diagnosis of chronic sinusitis have headaches or facial pain as their primary symptom, often with a CT showing minor mucosal thickening that has been attributed to sinus disease. Minor mucosal thickening on CT is a very non-specific finding and does not confirm a clinical diagnosis — it can be seen as an incidental finding in asymptomatic people and can reflect any mucosal irritation including allergy. A patient with episodic unilateral frontal headache and mild CT changes almost certainly has migraine, not sinusitis, and treating them for sinusitis will not help them.
For patients who genuinely do have chronic sinusitis, the conversation I have at the first appointment is about the long-term nature of the condition. CRS with polyps in particular is a chronic inflammatory condition that is managed rather than cured. Surgery can produce substantial improvement in quality of life — patients who have been breathing poorly and smelling nothing for years often find the improvement after FESS significant — but they need to understand that ongoing medical management, nasal irrigation, and regular follow-up are part of the commitment, not optional extras.
— Dr Jason Roth, MBBS, FRACS (ORL-HNS)
Specialist Otolaryngologist & Head and Neck Surgeon
Specialist registration — Otorhinolaryngology, Head & Neck Surgery
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