Diagnostic Imaging & Radiology Education and Resources

Technician with patientTo help our patients better understand the imaging services we offer, we provide more information about the different types of screenings and tests we perform at Skagit Regional Health. We have included when and why the imaging tests are typically performed and what you can expect for each of them. Please talk with your primary care provider or specialist for more information about imaging screenings and test procedures.

Computerized Tomography (CT) or CAT Scan

The computerized tomography (CT) scan, more commonly called “CAT” scan, looks at thin “slices” of the body using a rotating X-ray tube. It produces three-dimensional images of body structures, including organs or bones, and can study the chest, abdomen, pelvis, head, arms, legs, sinuses or blood vessels. It can also be used for biopsies, to see kidney stones, tumors or appendicitis.

Patients lie down on a bed or platform, which slowly moves through a large tube structure. Although it is enclosed, nothing will touch you during the exam. CT scans are usually tolerable for patients with claustrophobia. In some cases, you may need to drink or be injected with a contrast so your provider can better trace your condition.

Some CT scans can be done in a matter of seconds, while others may take up to 20 minutes. Your provider or CT technologist can provide more specific information.

Dual-Energy X-Ray Absorptiometry (DEXA) Bone Density Scan

A dual-energy X-ray absorptiometry (DEXA) is an advanced form of X-ray used to measure bone loss. It is performed with the patient lying on a padded table while a mechanical arm passes over the body. The scan usually takes less than 20 minutes.

Follow your provider’s orders to prepare for the test. Typically, you’ll be asked to discontinue any calcium supplements 24 hours prior to your test. We also suggest wearing comfortable clothes with no metal zippers or buttons so you can remain dressed during the scan.

Magnetic Resonance Imaging (MRI)

Magnetic resonance imaging or MRI is used to examine different types of soft tissue, including the brain, heart and abdomen as well as the vascular and skeletal systems. MRI provides some of the most detailed views of the body available today. Because of this, it is used to detect heart disease, heart attack, cancer, stroke, vascular disease, multiple sclerosis, tumors, infections and sports injuries.

Instead of X-rays, MRI uses magnetic fields, radio waves and complex computer processing to produce images. This is why patients are carefully screened for metal objects before entering the room. Patients with pacemakers, brain aneurysm clips or other implants cannot safely have an MRI unless the implants are MRI safe.

You will be asked to lie on your back on a table and stay still. A coil will be placed over the area being imaged. The certified technologist will leave the room during the exam and communicate with you through an intercom. The table will then move through the cylinder and powerful magnet to take images of the respective part of your body.

The MRI machine can be loud, so patients are typically offered earplugs. Generally, the test takes about 20 minutes.


Mammography imaging is used to perform mammograms, which uses a low-dose X-ray system to examine the breasts. Mammograms can detect breast cancer up to two years earlier than a patient or provider can feel a lump. Early detection of breast cancer is linked to more successful outcomes, so getting an annual mammogram is key for women over 40.

On the day of the exam, you should not wear deodorant, talcum powder or lotion under your arms or on your breasts. Before the exam, you’ll be asked to remove all jewelry and clothing above the waist and will be given a medical gown to wear that opens in the front. All screening mammogram images are analyzed using a computer-aided detection (CAD) system that is correlated with the radiologist findings. CAD analysis improves detection of early cancers by as much as 20 percent.

3D mammography is available at the Skagit Imaging Pavilion and at the Cascade Valley Hospital Diagnostic Imaging Department.

Nuclear Medicine

Nuclear medicine is an imaging technology that is safe and painless. This advanced technology uses very small amounts of radioactive materials that are specially formulated for this imaging test application. This allows providers to identify and assess medical problems based on how parts of the body function. For many studies there is a delay between receiving the radioactive material and the imaging. In these cases the patient may be able to leave and return to check in at imaging time.

Nuclear medicine is used to detect and determine the extent of a disease, infection or injury. For instance:

  • Bone scans are commonly used to monitor and stage prostate and breast cancer. These scans can also be used to monitor areas of inflammation, infection and pain.
  • Heart scans are used to assess heart function and are a non-invasive way to detect blockages in the coronary arteries. It helps to predict a patient’s risk for having a heart attack.
  • Lung scans are used to look at lung function and identify pulmonary embolus or blockages.
  • Gallbladder scans are used to detect cholecystitis.
  • Kidney scans show function and can detect renal artery hypertension.

You’ll be given a safe amount of radioactive material intravenously and then will be asked to lie on a table. The camera moves around the table. At Skagit Regional Health, we have cameras with software and hardware to reduce imaging time and radiation exposure. Nuclear medicine images actual body functions so imaging times vary depending on the imaging study.

Positron Emission Tomography Scan Plus Computerized Tomography (PET/CT)

A PET/CT scan is advanced diagnostic imaging and offers imaging that no other tests can provide, enabling providers to more accurately diagnose and identify disease. A PET/CT scan combines information about how your body is functioning with how it looks. This makes the test more convenient for patients while providing maximum information to the provider, saving both time and money in diagnostics and treatment.

This type of scan is used primarily in oncology to accurately diagnose or stage cancer, check for tumor recurrence and to monitor cancer therapy. It can also be used to determine what combination of surgery, radiation therapy or chemotherapy is most likely to be successful in managing the disease. PET is also commonly used in the diagnosis of neurological issues.

You’ll be asked not to eat or drink anything four to six hours before an exam. This advanced technology uses very small amounts of radioactive materials that are specially formulated for this imaging test application. This is manufactured specifically for you, so if for any reason you’re unable to meet the scheduled exam time, please notify the facility at least the day before the exam.

After drinking the compound, you’ll wait about 60 minutes so it has time to distribute throughout your body and be processed by the body. During the exam, you’ll lie on a scanner table, which moves through the scanner to detect and record signals from the tracers. The CT portion takes less than two minutes, and the PET exam can take up to 30 minutes.


Ultrasound uses high-frequency sound waves and their echoes to display a two-dimensional image of soft tissue in the body. It is used to view and diagnose conditions in organs such as the liver and spleen, arteries, veins, legs, arms and the neck, and to guide needle biopsies. Ultrasound can measure the flow of blood through the kidneys and allow physicians to see kidney stones. It is also commonly used on pregnant women to check the baby’s size, development and position.

Depending on the level of detail required, an ultrasound can take five minutes or be more than an hour. Before the ultrasound begins, a gel will be applied to help the probe move over your skin. In some cases, the probe will be inserted into your body. If any preparation is needed, your provider will provide additional instructions.


X-rays use high-energy electromagnetic waves to produce still images of bones and joints to help diagnose fractures or abnormalities. When used in conjunction with a fluoroscope, providers can trace the movement of contrast media through the joints and organs.

During an X-ray, you’ll be asked to stay still and hold your breath while an image is taken. The length of the test depends on the procedure performed, with fluoroscopy taking longer. For some exams, such as those of the gastrointestinal system, you’ll be asked to not consume food or beverages for a period of time before the exam. Before getting an X-ray, please tell the technologist if there’s a possibility you could be pregnant.

For More Information about Diagnostic Imaging & Radiology at Skagit Regional Health

If you have questions about our diagnostic imaging services or would like more information, please contact one of our team members at any of our Skagit Regional Health locations at 360-428-2168.