Sinusitis is an inflammation of the paranasal sinuses, which may or may not be as a result of infection, from bacterial, fungal, viral, allergic or autoimmune issues. Newer classifications of sinusitis refer to it as rhinosinusitis, taking into account the thought that inflammation of the sinuses cannot occur without some inflammation of the nose as well (rhinitis).
There are several paired paranasal sinuses, including the frontal, ethmoid, maxillary and sphenoid sinuses. The ethmoid sinuses can also be further broken down into anterior and posterior, the division of which is defined as the basal lamella of the middle turbinate. Depending on the sinus they are involving, sinusitis can be:
- Maxillary sinusitis - can cause pain or pressure in the maxillary (cheek) area (e.g., toothache, headache)
- Frontal sinusitis - can cause pain or pressure in the frontal sinus cavity (behind/above eyes), headache
- Ethmoid sinusitis - can cause pain or pressure pain between/behind eyes, headache
- Sphenoid sinusitis - can cause pain or pressure behind the eyes, but often refers to the vertex of the head
Recent theories of sinusitis indicate that it often occurs as part of a spectrum of diseases that affect the respiratory tract (i.e. - the "one airway" theory) and is often linked to asthma. All forms of sinusitis may either result in, or be a part of, a generalized inflammation of the airway so other airway symptoms such as cough may be associated with it.
Types
Sinusitis can be acute (going on less than four weeks), subacute (4-12 weeks) or chronic (going on for 12 weeks or more). All three types of sinusitis have similar symptoms, and are thus often difficult to distinguish.
Acute sinusitis is usually precipitated by an earlier upper respiratory tract infection, generally of viral origin. Virally damaged surface tissues are then colonized by bacteria, most commonly Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and Staphylococcus aureus. Other bacterial pathogens include other streptococci species, anaerobic bacteria and, less commonly, gram negative bacteria. Another possible cause of sinusitis can be dental problems that affect the maxillary sinus. Acute episodes of sinusitis can also result from fungal invasion. These infections are most often seen in patients with diabetes or other immune deficiencies (such as AIDS or transplant patients on anti-rejection medications) and can be life threatening. In type I diabetes, ketoacidosis causes sinusitis by Mucormycosis.
Chronic sinusitis is a complicated spectrum of diseases that share chronic inflammation of the sinuses in common. The causes are multifactorial and may include allergy, environmental factors such as dust or pollution, bacterial infection, or fungus (either allergic, infective, or reactive). Non allergic factors such as vasomotor rhinitis can also cause chronic sinus problems. Abnormally narrow sinus passages, which can impede drainage from the sinus cavities, can also be a factor.
Symptoms include: nasal congestion; facial pain; headache; fever; general malaise; thick green or yellow discharge; vertigo or lightheadedness; blurred vision, feeling of facial 'fullness' or 'tightness' which worsens on bending over; aching teeth, and halitosis.
Very rarely, chronic sinusitis can lead to Anosmia, the inability to smell or detect odors.
In a small number of cases, chronic maxillary sinusitis can also be brought on by the spreading of bacteria from a dental infection.
Attempts have been made to provide a more consistent nomenclature 6 for subtypes of chronic sinusitis. A task force for the American Academy of Otolaryngology - Head and Neck Surgery / Foundation along with the Sinus and Allergy Health Partnership broke Chronic Sinusitis into two main divisions, Chronic Sinusitis without polyps and Chronic Sinusitis with polyps (also often referred to as Chronic Hyperplastic Sinusitis). Recent studies which have sought to further determine and characterize a common pathologic progression of disease have resulted in an expansion of proposed subtypes. Many patients have demonstrated the presence of eosinophils in the mucous lining of the nose and paranasal sinuses. As such the name Eosinophilic Mucin RhinoSinusitis (EMRS) has come into being. Cases of EMRS may be related to an allergic response, but allergy is often not documentable, resulting in further subcategorization of allergic and non-allergic EMRS.
A more recent, and still debated, development in chronic sinusitis is the role that fungus may play. Fungus can be found in the nasal cavities and sinuses of most patients with sinusitis, but can also be found in healthy people as well. It remains unclear if fungus is a definite factor in the development of chronic sinusitis and if it is, what the difference may be between those who develop the disease and those who do not.
Diagnosis
Acute sinusitis is usually diagnosed clinically. Clinically bacterial and Viral Acute sinusitis are difficult to distinguish however, disease duration less than 7 days is considered as a Viral whereas more than 7 days are considered as a bacterial sinusitis (usually 30% to 50% are Bacterial sinusitis).
In suspected Acute Fungal Sinusitis - Multiple biopsy of involved area are performed to confirm etiological diagnosis.
Nosocomial Acute sinusitis is confirmed with the help of CT scan of the sinuses.
In Chronic sinusitis (lasting more than 12 weeks) CT scan, tissue sample for Histology and Cultures can be used for diagnosis.
In Chronic Bacterial sinusitis CT scan is used to define the range, extent of the disease and response of the treatment course. Tissue samples for Histology and culture is obtained to confirm a diagnosis.
Allergic fungal sinusitis are often seen in a person with asthma and nasal polyps. Multiple Biopsy is informative to confirm the diagnosis.
When imaging techniques are required for diagnosis CT scanning is the method of choice. If allergies are suspected, allergy testing may be performed.
ENT specialists utilize a procedure known as nasal endoscopy (if nasal endoscopy is indicated) to diagnose sinus infection. This involves inserting a flexible fiber-optic tube with a light and camera at its tip into the nose to examine the nasal passages and sinuses. This is generally a completely painless procedure which takes between 5 to 10 minutes to complete.
Treatment
Acute Sinusitis. There are over the counter medicines that can relieve some of the symptoms associated with sinusitis, such as headaches, pressure, fatigue and pain. Usually these are a combination of some kind of antihistamine along with decongestant or pain reliever. Seeing a doctor will usually result in a prescription for antibiotics and a recommendation for rest.
Recently, the FDA affirmed that antihistamines added to sinus products are not rational, as they don't reduce nasal congestion and can worse the condition by increasing the viscousity of the mucous (due to their drying effect; anticholinergic effects) making sinus drainage difficult.
Therapeutic measures range from the medicinal to the traditional and may include nasal irrigation or jala neti using a warm saline solution, hot drinks including tea and chicken soup, over-the-counter decongestants and nasal sprays, and getting plenty of rest. Analgesics (such as aspirin, paracetamol (acetaminophen) or ibuprofen) can be used, but caution must be employed to make sure the patient does not suffer from aspirin-exacerbated respiratory disease (AERD) as this could lead to anaphylaxis.
If sinusitis doesn't improve within 48 hours, or is causing significant pain, a doctor may prescribe antibiotics (Amoxicillin usually being the most common) with amoxicillin/clavulanate (Augmentin/Co-Amoxiclav) being indicated for patients who fail amoxicillin alone. Fluoroquinolones, and less frequently Doxycycline are used in patients who are allergic to penicillins.
A recent British study has found that for most cases of acute sinusitis, antibiotics and nasal corticosteroids work no better than a placebo.
Chronic Sinusitis. Nasal irrigation and flush promotes sinus cavity health, and patients with chronic sinusitis including symptoms of facial pain, headache, halitosis, cough, anterior rhinorrhea (watery discharge) and nasal congestion found nasal irrigation to be "just as effective at treating these symptoms as the drug therapies." In other studies, "daily hypertonic saline nasal irrigation improves sinus-related quality of life, decreases symptoms, and decreases medication use in patients with frequent sinusitis," and is "recommended as an effective adjunctive treatment of chronic sinonasal symptoms." Some people use bulb syringes, squirt bottles, and neti pots. Others use pulsating irrigation devices that deliver an intermittent pulsing saline rinse to remove bacteria, purulent material, and help restore ciliary function.
Some published medical reports indicate pulsatile lavage is more effective at cleansing and removing bacteria than non-pulsating nasal wash products like bulb syringes, neti pots and squeeze bottles, which rely simply on gravity and conventional flow. A pulsating nasal irrigation device delivers a controlled flow with pressure control that may be adjusted for individual comfort. Medical reports support that positive pressure irrigation retains a larger volume of solution and irrigates the sinuses more consistently than other methods.
For most patients the surgical approach is not superior to appropriate medical treatment. Surgery should only be considered for those patients who do not experience sufficient relief from optimal medication.
A relatively recent advance in the treatment of sinusitis is a type of surgery called functional endoscopic sinus surgery (FESS), whereby normal clearance from the sinuses is restored by removing the anatomical and pathological obstructive variations that predispose to sinusitis. This replaces prior open techniques requiring facial or oral incisions and refocuses the technique to the natural openings of the sinuses instead of promoting drainage by gravity, the idea upon which the Caldwell-Luc surgery was based.
Another recently developed treatment is balloon sinuplasty. This method, similar to balloon angioplasty used to "unclog" arteries of the heart, utilizes balloons in an attempt to expand the openings of the sinuses in a less invasive manner. Its final role in the treatment of sinus disease is still under debate but appears promising.
Based on the recent theories on the role that fungus may play in the development of chronic sinusitis, newer medical therapies include topical nasal applications of antifungal agents. Much of the original research indicating fungus took place at the Mayo Clinic and they have since patented this treatment option. Although there are some licensing battles taking place over these drugs as a result of the patent, they are currently available for other uses and therefore can be compounded by pharmacies or even by the patient.
A number of surgical approaches can be used, either by endoscopy or conventional incision generally through nose or mouth.
Endoscopic nasal Surgery allows more functional approach than by radical antrostomy.
Intranasal endoscopic operations permit minimal trauma to adjacent tissues and precise removal of the diseased mucosa.
If fibrosis of the antrum is present (natural ostium can be completely obstructed) by infection and inflammation; intranasal inferior meatal antrostomy can be used to ease drainage from the antrum. Or, intranasal indoscopic techniques can be used to create a middle meatal antrostomy (e.g. middle turbinate is lifted and infundibulum is localised and enlarged anteriorly, generally excision of anterior end of the unicate process is not required, antrum can be inspected through antrostomy by the use of 30 and 70 degree rigid endoscopy.)
For persisting Sinusitis Caldwell-Luc radical antrostomy can be used (e.g. incision in the upper gum, opening in the anterior wall of the antrum, removal of the entire diseased maxillary sinus mucosa and drainage is allowed into inferior meatus by creating a large window in the lateral nasal wall.)
Once incissional entry is gained into the paranasal sinus, surgery can be extended to another sinus or other adjacent anatomical structures. e.g. internal maxillary artery, pterygopalatine fossa and sphenopalatine ganglion.
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