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Nasal Polyps
ALTERNATIVE NAMES: Nasal polyposis.
DEFINITION: Polyps forming from either structures within the nose or paranasal sinuses that project into the nasal cavity.
WHAT IS GOING ON IN MY BODY? The nasal cavities can be viewed as two triangular passageways separated from each other by the nasal septum, which is a cartilaginous and bony wall. Each lateral wall of the nose contains three important structures called the lower, middle, and superior turbinates. Their function is to warm, cleanse, and humidify air passing through the nose. Under the middle turbinate is one of the paranasal sinuses, the ethmoid sinus which is discussed in greater detail under ethmoiditis. Also draining under the middle turbinate are the frontal and maxillary sinuses located in the forehead and central portion of the face respectively. The nose is a very efficient filter, removing over 80% of particles larger than 6 microns which would include most particulates and pollens. Most of this material is deposited around the front portion of the middle turbinate.
Since the nose is the interface between the air in the environment and the air in the lungs, it is bombarded by a variety of agents that can cause chronic inflammation. These agents would include pollens, mold spores, animal dander, dust mite and cockroach feces, particulates such as dust and dirt, and lastly pollutants. Any of these materials can cause inflammation inside the nose and sinuses. Nasal polyps are the final result of long-term untreated nasal inflammation. They often look like grapes or small balloons hanging off the turbinates or coming out from underneath the middle turbinate when they arise from the paranasal sinuses. Because there are a variety of different forms of inflammation inside the nose, nasal polyps can be caused by a variety of different disorders. One of the most common associations seen with nasal polyps is the existence of asthma. Non-allergic rhinitis with eosinophilia syndrome (NARES), allergic rhinitis, chronic bacterial infection, structural rhinosinusitis, aspirin sensitivity syndrome, and chronic fungal allergic sinusitis are the most common causes of nasal polyps.
Polyps in children deserve a special mention. They must be considered to be caused by cystic fibrosis until proven otherwise. Cystic fibrosis is one of the most common causes of nasal polyps in children. During early childhood 10% of children with CF will have nasal polyps. This number climbs to almost 100% by adolescence. This disorder is a genetically determined systemic illness whereby the production of mucus-secreting organs is too thick and cannot be cleared, thus resulting in damage to the mucus-producing structure. In the nasal epithelium very thick secretions result which clear poorly from the nose or sinuses, with consequent chronic infection and ensuing nasal polyposis. These individuals also have significant lung disease caused by poor clearance of secretions in the bronchial tubes and thus are quite susceptible to pneumonia. Prior to the advent of antibiotics and other forms of supportive care, cystic fibrosis had a 100% mortality rate during childhood and early adulthood.
WHAT ARE THE SIGNS AND SYMPTOMS? It is unusual that nasal polyps will form in the absence of other chronic illnesses. Therefore, individuals who develop polyps already have been having sinus and nasal symptoms, such as nasal obstruction, chronic facial pain or headache, excessive nasal secretion, and impaired sense of smell. They may also have minor symptoms, such as excessive post nasal drip or chronic cough. The development of nasal polyposis is usually, therefore, noticed by the patient because the nasal obstruction becomes much more severe. Other symptoms may intensify, such as chronic facial discomfort, and also pre-existing infection may become much more difficult to resolve. An unusual sign in individuals with nasal polyps is increasing distance between the two eyes, which is particularly notable in children in whom expanding nasal polyps are forming.
Rarely will an individual actually have polyps start to protrude through the pares. Typically on examination, pale, slightly pink to gray balloon-like swellings are seen inside the nose. If the underlying inflammation is particularly intense, there will be a parallel increase in the amount of redness in the polyps and lining of other intranasal structures.
WHAT ARE THE CAUSES AND RISKS? As previously mentioned, any disorder that causes long-term sinus or nasal inflammation can result in nasal polyps. Chronic allergies, asthma, allergic fungal sinus infections, cystic fibrosis, aspirin sensitivity syndrome, structural abnormalities, and NARES syndrome are all some of the causes.
The main risks of nasal polyps have to do with their obstructive effects upon the sinus drainage. If this occurs, then either chronic infection can ensue, which would be characterized by facial pain, infected-appearing drainage, and worsening nasal stuffiness. Polyps can also cause a more symptomatically silent form of sinus obstruction termed a mucocele. A mucocele is an expanding collection of mucus within a sinus. As it continues to expand, bone erosion can occur. Since the frontal sinus forms part of the boundary for the eye socket, an expanding mucocele will often present with displacement of the eyeball inferiorly, laterally and forward. Since the back wall of the frontal sinus forms part of the brain cavity, a particularly large mucocele may erode this back wall of the frontal sinus and start to put pressure on the frontal lobe of the brain. Expanding mucous collections within the sphenoid sinus can present with double vision or actual loss of visual acuity as they press on the nerves that control eye movement and vision. Mucoceles within the ethmoid sinus usually result in displacement of the globe, although in a more lateral and forward direction. Maxillary sinus mucoceles usually result in nasal obstruction, but sometimes numbness of the cheek can occur. The nasal obstruction occurring from polyps in an asthmatic result in more mouth-breathing. As a result, the asthmatic loses the benefits of nasal humidification, air cleansing, and air warming. This unconditioned air can clearly make asthma management more problematic. Also in the asthmatic, nasal polyps can be associated with a more difficult time controlling the asthma. Polyps in children can cause some facial changes, such as increasing the distance between the eyes. Since there is such a high incidence of loss of sense of smell with nasal polyps, there are risks associated with the inability to perceive odors. If a person cannot smell, then they may eat spoiled food and get food poisoning or not be able to smell a natural gas leak and put themselves and others at risk for a possible natural gas explosion.
HOW TO PREVENT THE DISEASE: The most important means of preventing nasal polyps is to control the underlying inflammation. For example, in those individuals with prolonged or frequent allergic rhinosinusitis, environmental changes, allergen avoidance, antihistamines, nasal steroids, and/or allergy shots may be necessary. Unfortunately, asthma management alone will not prevent nasal polyps from forming in the asthmatic. Often, these individuals need chronic nasal steroid therapy. Patients having chronic bacterial infections need to be on appropriate antibiotics to try to resolve the infection and prevent the nasal polyps. However, if the infections are not cured by antibiotics or they continue at four to five or more per year, then surgery may be necessary (see chronic sinusitis). Individuals in whom there may be structural causes of the polyps would need to have the structural problems corrected surgically. In the aspirin sensitive patient, aspirin desensitization may help. Use of some of the newer leukotriene antagonists may also be beneficial, particularly in polyps associated with asthma, aspirin sensitivity, and NARES syndrome.
HOW IS IT DIAGNOSED? Large nasal polyps are easy to see just by examining the front part of the nose. Smaller polyps may require telescopic identification. CT scanning in patients with nasal polyps helps to clarify the extent of the underlying sinus disease. Usually nasal polyps are present in both sides of the nose. If polyps are only on one side, then it may be a tumor instead. In this case, it is usual to biopsy it prior to deciding on a course of medical or surgical therapy.
WHAT ARE THE LONG-TERM EFFECTS? This was covered under Causes and Risks.
AM I PUTTING OTHERS AT RISK? No.
WHAT ARE THE TREATMENTS? Not every individual who has nasal polyps requires surgical removal. Not infrequently they can be suppressed with chronic nasal steroid therapy and management of the underlying disorder (allergies, infection, etc.). For acute nasal polyp formation or acute enlargement of pre-existing nasal polyps, oral steroids are effective to bring them back down to their original size. In certain extreme situations where all forms of medical and surgical management fail, chronic oral steroids may be necessary. For those individuals with significant symptoms or complications from their polyps, surgical removal is necessary. If the polyps are arising solely from the turbinates and are not creating any other symptoms, simple removal of the polyps followed by nasal steroids is often curative. However, in those individuals who continue to have significant symptoms or complications, or who are not responding to aggressive medical therapy, surgical removal of the ethmoid sinus and restoration of the natural openings into the sphenoid, frontal, and maxillary sinuses is required. Most individuals with polyps, even though they have been successfully removed surgically, will need to be on chronic nasal steroid therapy and continue to have the underlying disease processes controlled (allergy management, aspirin desensitization).
WHAT ARE THE SIDE EFFECTS TO THE TREATMENTS? The side effects will be specific to the particular medications employed. The side effects to simple polypectomy may be hemorrhage, although this is quite infrequent. The major side effects to surgery would be significant nasal hemorrhage (less than 1%), post-operative infection (less than 5%), cerebral spinal fluid leak (0.5 to 0.1%), injury to eye structures are rare, tear duct injury (less than 1%), and polyp recurrence (approximately 50%).
WHAT HAPPENS AFTER TREATMENT? If medical management is successful, then the patient's symptoms should be reversed. Unfortunately, there is a fairly high polyp recurrence rate that parallels the underlying disorder. Individuals with aspirin sensitivity have between 50 and 75% polyp recurrence rates. Asthmatics may have approximately a 50% polyp recurrence rate. Fortunately, those with structural or bacterial causes of nasal polyps have an infrequent polyp recurrence rate of less than 25%. Children with cystic fibrosis continue to have difficulties with polyp formation. In polyp-forming diseases, the rate of polyp recurrence is lessened when more complete sinus procedures are performed.
HOW DO I MONITOR THE DISEASE? The patient monitors polyps mostly by the symptoms from which they suffer. One of the earliest symptoms of polyp recurrence is a loss of sense of smell, which often precedes the nasal obstruction. Therefore, in an individual suffering from polyps who has had successful management with restoration of their sense of smell, should it decline, they would need to seek medical attention fairly immediately. Because of the high rate of polyp recurrence, regular medical follow-up helps to determine the rapidity of regrowth and what medical regimens may be necessary.
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