Sinusitis (or rhinosinusitis) is defined as an inflammation of the mucous membrane that lines the paranasal sinuses and is classified chronologically into several categories:

    •    Acute rhinosinusitis — a new infection that may last up to twelve weeks and can be subdivided symptomatically into severe and non-severe. Acute sinus infections usually start with a viral cold and approximately 2% will turn into a bacterial sinus infection, generally after 7-10 days from the start of a cold. Acute sinus infections may also start after a dental infection or complication from a dental procedure.

    •    Recurrent acute rhinosinusitis — four or more separate episodes of acute sinusitis that occur within one year episodes between infections;

    •    Chronic rhinosinusitis — when the signs and symptoms last for more than 12 weeks; and

    •    Acute exacerbation of chronic rhinosinusitis — when the signs and symptoms of chronic rhinosinusitis exacerbate, but return to baseline after treatment.

All these types of sinusitis have similar symptoms, and are thus often difficult to distinguish. Acute sinusitis is very common. Roughly ninety percent of adults have had sinusitis at some point in their life.

Acute and Chronic Rhinosinusitis

Sinusitis is a large group of diseases of the sinus lining(mucosa and sometimes the surrounding structures. Sinusitis occurs when the mucosa becomes inflamed. The inflammation of the lining of the sinuses can become so extensive that it causes the very small sinus ostia (openings) to become blocked. 

Most cases of rhinosinusitis are caused by viral colds but can also be caused by allergies, exposure to chemicals and smoke or after dental procedures. In general, it takes about 7-10 days for a bacterial sinus infection to start following a cold. 

Signs and symptoms of an acute bacterial sinus infections include:

    •    pain the upper teeth (often worse with walking)
    •    thick, purulent nasal discharge (not just a small amount of mucous on tissue)
    •    worsening of nasal congestion with a decrease/ loss in sense of smell
    •    'Double Worsening' - illness worsening after approximately 7 days

It generally takes about 7-10 days for a cold to become a bacterial sinus infection and can last up to 12 weeks. 

With good care, most sinus infections will clear without any complications or long term problems. Most infections will clear with adjunctive therapy, including saline rinses, decongestants and intranasal corticosteroids to decrease the presence of inflammation. Antibiotics are used for severe symptoms with the presence of a fever and for symptoms not clearing or worsening after trying other treatments. Chronic rhinosinusitis (CRS) is a medical condition presenting for greater than 12 weeks with the following symptoms:

    •    mucopurulent discharge (thick colored mucous - not a little bit on Kleenex and present through the whole day)

    •    nasal obstruction (congestion and the inability to breathe through the nose)

    •    decreased sense of smell (often accompanied with decreased sense of taste)

    •    facial pressure/ congestion (but ONLY in the presence of other nasal symptoms- chronic/ intermittent facial pain and pressure without any other symptoms is RARELY due to sinusitis)

These symptoms are also found along with:

    •    endoscopic findings of purulent mucous (pus) in the middle meatus (major drainage area of the sinuses)

    •    nasal polyps

    •    CT scan changes of sinusitis (plain Xrays are not sensitive enough and MRIs are too sensitive for diagnosis)


Patients often describe CRS as a “cold that never went away” and are often under the impression that it is a chronic infection and they have often been treated with several courses of antibiotics without resolution of their symptoms. CRS is an inflammatory condition affecting the lining of the nose and sinuses and often has no definable cause (often thought of an overactive immune response that does not shut off). CRS produces a similar immunologic response as other disease where the inside or the body is separated from the outside world by a mucous membrane (ie. asthma, dermatitis/ eczema, inflammatory bowel disease, etc) and can provide a wide range of symptoms and presentations... not all patients are the same! 

What is NOT sinusitis?

Many people feel that they have sinus problems as most of us are aware that the sinus are in the face (and there are many medications advertised on TV for “sinus pain”). Symptoms that are not suggestive of sinusitis include: 

    •    facial pain that comes and goes out of the blue
    •    facial pain that is associated with pain in the temples, back of the neck
    •    facial 'pressure' / sinus headaches (related to muscle tension or migraine-type headache)
    •    nasal congestion that alternates from side to side (this is the nasal cycle and is caused by turbinate swelling
    •    post nasal drainage and phlegm without other nasal symptoms
Diagnosing CRS

Diagnosis of CRS requires a complete history and endoscopic examination. CT scans are used to help assess the sinuses that cannot be visualized with an endoscope. A clear CT scan is a very strong indication that sinusitis is not a cause of congestion, pain, post nasal drainage, etc.

Treatment of CRS

CRS is a medical disease with surgical treatment used for medically resistant symptoms or with anatomical blockage (deviated septum, extensive nasal polyposis, etc). Sinus surgery is not a cure for CRS, but is used to help medical treatments work better and are most often continued after any surgical treatment. 

Some patients experience very difficult to treat and refractory sinus problems. This is common in patients with untreated allergies, asthma and allergies to Aspirin/ NSAIDs. Often, a dedicated sinus surgeon will work with an allergist and a lung doctor (Pulmonologist) to help treat patients with severe symptoms.