A sinus X-ray (or sinus series) is an imaging test that uses a small amount of radiation to visualize details of your sinuses. Sinuses are paired (right and left) air-filled pockets that circumscribe the nasal structures. They clean the air breathed through the nose and provide shape to the face.
There are four different pairs of sinuses:
- Frontal sinuses: The right and left frontal sinuses are located over and around the eyes. Specifically, they are situated near the center of the forehead just above each eye.
- Maxillary sinuses: The maxillary sinuses are the largest of the sinuses. They are positioned behind the cheekbones near the maxillae, or upper jaws.
- Sphenoid sinuses: The sphenoid sinuses are located behind the skull, near the optic nerve and the pituitary gland.
- Ethmoid sinuses: These sinuses are situated between the eyes and the bridge of the nose. Ethmoid sinuses consist of a collection of six to 12 small air cells that open independently into the nasal passage. They are divided into front, middle, and rear groups.
A sinus X-ray helps doctors detect problems with the sinuses. Sinuses are normally filled with air, so the passages will appear black on an X-ray of healthy sinuses. A grey or white area on the X-ray of the sinuses indicates a problem. This is most often due to inflammation or a buildup of fluid in the sinuses (e.g. sinusitis).
A sinus X-ray may also be called X-ray of the sinuses, or paranasal sinus radiography. It is a noninvasive test that can be completed quickly and with little discomfort or pain.
Your doctor will order a sinus X-ray if you’re experiencing symptoms of a sinus problem or sinusitis, also known as a sinus infection. Sinusitis occurs when the sinuses become inflamed, causing a buildup of pus and mucus in the sinuses. The condition is usually caused by a bacterial infection that develops after a viral infection. Symptoms of sinusitis include:
- stuffy nose with thick nasal secretions that may appear white, yellow, or green
- pain or tenderness in the forehead, between the eyes, in the cheeks, and upper jaw
- swelling around the eyes, around the nose, and in the cheeks
- decreased sense of smell
- postnasal drainage
- sore throat
Sinusitis can either be acute or chronic. Acute sinusitis typically lasts between one and two weeks. Infections that can cause acute sinusitis include viral infections, fungal infections, and bacterial infections. Sinusitis can also be triggered by:
- reduced immune function
- prolonged colds or flus
- tumors or polyps in the nasal passages or sinuses
- enlarged or infected adenoids, which are glands located in the roof of the mouth
Chronic sinusitis causes the sinuses to stay inflamed and infected for 12 weeks or longer. The condition can develop as a result of:
- viral infections
- recurring acute sinusitis
- trauma to the face
- problems with the respiratory tract
- immune system deficiency disorders
A sinus X-ray can also be used to detect other sinus problems, including a tumor or bleeding in the sinuses. In some cases, it may be used to help diagnose meningitis or orbital cellulitis. Meningitis is a bacterial or viral infection in the brain and spinal cord, while periorbital cellulitis is an infection around the eye.
A sinus X-ray typically takes place at a hospital or medical laboratory. It may be performed on an outpatient basis or as part of your stay in a hospital. There is no preparation required. However, you will need to remove any jewelry or metal objects you may be wearing before the test. A radiologist or X-ray technician will perform the sinus X-ray.
You may be asked to sit or lie down on an X-ray table. The radiologist will place a lead apron over your torso to help protect you from radiation. They will then place your head in line with the X-ray machine. You will need to hold this position for a few moments while the X-ray image is being produced. The radiologist will step behind a protective window to take the X-ray.
It is important to remain still as possible while the X-ray is being taken, otherwise the image will be blurred. It will only take a couple of seconds for the X-ray image to be completed. You may hear a clicking sound, similar to the sound a camera makes when taking a picture.
The radiologist may need to reposition you several times in order to get images of all the sinuses.
A sinus X-ray involves the use of radiation to create images of the body. While it uses relatively low amounts of radiation, there is still a risk every time the body is exposed to radiation. It is important to notify your doctor about any medical tests you’ve had in the past. This will help your doctor make sure that you’re not overexposed to radiation.
It is also vital to tell your doctor if you are pregnant or think you might be pregnant, as radiation can cause birth defects. Your doctor may decide to order a different test or to use special measures to protect your baby from radiation.
Sinus X-rays are less invasive than other types of sinus tests, but they are also less comprehensive. In most cases, a sinus X-ray will be one test performed in a series of tests. A sinus X-ray may indicate the presence of a problem, but other sinus tests can help determine the specific cause of a sinus problem.
These tests may include:
- nasal endoscopy or rhinoscopy
- blood tests
- CT or MRI scan
- sinus puncture and bacteria culture
The specific types of additional tests performed will vary depending on your particular situation. Speak with your doctor about the results of your sinus X-ray and next steps in the diagnostic process.