Nasal Polyps

Description

Nasal polyps are soft, benign mucosal growths that occur in the paranasal sinuses. They are a few millimeters to several centimeters in size and can grow as far as into the nasal cavity.

Symptoms

Nasal polyps sometimes exist for long periods of time without causing discomfort. However, depending on their location, size and number, they can interfere with the air flow in the sinuses and nose.

These symptoms may indicate nasal polyps: difficulties breathing through the nose (nasal obstruction), bad breath (sufferers breathe more through the mouth than the nose, so the oral mucosa dries out), snoring during sleep, twangy voice (due to blocked nose), olfactory dysfunction (sense of smell impaired or lost because air does not reach the olfactory cells in the upper nasal cavity).

Frequent headaches, tenderness above the sinuses, constant mucus flow in the throat - these signs indicate persistent sinusitis which is both a catalyst and consequence of nasal polyps.

Causes and Risks

It is not known exactly how nasal polyps arise. Experts suspect that there is a certain predisposition to the disease. Precursors in most cases are persistent inflammation of the mucous membranes in the nose and paranasal sinuses (sinusitis).

The causes might for example lie in the individual anatomy: curvature of the nasal septum or other anatomical abnormalities (e.g. of the nasal turbinates) that have a relatively adverse effect in some circumstances.

The mucous membrane in the nose and sinuses can also become chronically irritated and swollen for other reasons, and thus lead to nasal polyps. Many patients with nasal polyps suffer simultaneously from an allergy such as hay fever or an allergy to house-dust. People with bronchial asthma also tend to form nasal polyps, likewise those who have an intolerance for painkillers.

Nasal polyps occur in children only very rarely, with one exception: about one-third of all children suffering from the congenital metabolic disease cystic fibrosis also have nasal polyps.

In rare cases, nasal polyps arise as a result of genetic mutation: the disease is called primary ciliary dyskinesia. Here the cilia on the mucosal cells generally have only limited movement, so that they perform their tasks poorly or not at all. Consequently, the cleaning mechanism in the nose and sinuses no longer functions optimally, which promotes inflammation and thus nasal polyps.

Examination and Diagnosis

Initially, the doctor inquires about the patient's symptoms and underlying medical conditions (e.g. asthma, allergies). Symptoms such as an impaired sense of smell, trouble breathing through the nose or frequent sinus infections may already raise suspicions of nasal polyps. Large nasal polyps, which extend into the nasal cavity, can even be distinguished with the naked eye. With the help of a diagnostic microscope and a nasal endoscope - a thin instrument with built-in light source - the doctor may also often recognize smaller or more deep-seated polyps.

Under certain circumstances, additional investigations are needed to gain certainty. Imaging methods are suited for this purpose, particularly computed tomography (CT) or digital volume tomography (DVT). Ultrasound and magnetic resonance imaging (MRI) are relevant for the diagnosis of nasal polyps only in special situations.

Nasal polyps usually occur on both sides, i.e. in the sinuses on both sides of the head. Unilateral growths should always be examined more carefully, especially if they frequently cause nosebleeds. Because - rarely - is it then not a polyp but a malignant tumor. If this is suspected, the doctor takes a tissue sample which is then examined under a microscope.

To check whether an allergy such as hay fever could be the precursor of nasal polyps, the doctor uses various allergy tests - initially the prick test. Since the results of this skin test do not entirely apply to the nasal mucosa, a nasal challenge test can then be carried out as well: the potential allergy trigger is sprayed on the nasal mucosa, then a measurement is taken as to whether air resistance in the nose increases. A painkiller intolerance can be detected by blood tests or by means of challenge tests: after administration of the suspect painkiller, resistance in the bronchi or in the nose is measured.

Treatment

Medications that are modeled on the body's own cortisol hormone (cortisone) often help against nasal polyps. These glucocorticoids can especially cause the smaller nasal polyps to shrink.

If an allergy is the precursor of nasal polyps, it must be treated accordingly. The doctor then recommends, for example, medicines against allergic reactions, called antihistamines. The patient should avoid the allergy triggers whenever possible. Often a specific immunotherapy (desensitization) comes into consideration. With painkiller intolerance, an adaptive deactivation can bring improvement.

If the drug therapy failed or if the polyps are already very large, surgery may be considered. The removal of individual, small polyps (polypectomy) can potentially be done on an outpatient basis in a doctor's office under local anesthesia. Extensive interventions usually take place instead on an in-patient basis in a hospital under general anesthesia. The doctor will often simultaneously conduct an endoscopic sinus surgery, for example eliminating further mucosal growths. Or he enlarges the openings between the sinuses and nasal cavity, so that the sinuses are again better ventilated. Sometimes it may also be appropriate to straighten a crooked nasal septum or shrink enlarged turbinates.

Course and Prognosis

Since nasal polyps grow slowly, patients often get used to the symptoms and only seek medical attention later. With proper treatment, the symptoms can be alleviated. Surgical removal of nasal polyps often quickly relieves the discomfort. Nevertheless, in about 75 percent of patients, the polypys grow again in the first few years after their removal. Therefore it is advisable to use long-lasting cortisone nasal sprays after nasal polyp surgery. This can prevent a recurrence of polyps in the nose. One can follow the progress with the help of computer tomography. Here it is advisable to employ the less radiation-intense digital volume tomography (DVT).