Medicare may cover positron emission tomography (PET) scans, although generally a doctor must order the scan, and it must be for a medically necessary reason.

This article explains why a PET scan is ordered, what it can detect, and how it is done. It then looks at coverage and costs.

We may use a few terms in this piece that can be helpful to understand when selecting the best insurance plan:

  • Deductible: This is an annual amount that a person must spend out of pocket within a certain time period before an insurer starts to fund their treatments.
  • Coinsurance: This is a percentage of a treatment cost that a person will need to self-fund. For Medicare Part B, this comes to 20%.
  • Copayment: This is a fixed dollar amount that an insured person pays when receiving certain treatments. For Medicare, this usually applies to prescription drugs.
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A PET scan is a type of imaging test, which is used to diagnose medical conditions. It shows bodily activity on a cellular level by using radiation.

PET scans fall into two types:

Myocardial Perfusion PET (also called Adenosine or Rubidium PET) is generally used for cardiac examinations.

FDG PET can also be used to study the heart, as well as the brain, and for tumors or other types of infection.

Both PET scans use a radioactive tracer to visualize specific areas of the body.

Before the scan, a person is required to ingest, inhale, or receive an injection of a dye that has radioactive tracers, also called radio pharmaceuticals or radiotracers. The body’s organs absorb the tracers, which allows a medical professional to examine them.

PET scans are generally used in neurology and cardiology, and for cancer treatment, and may be combined with a magnetic resonance imaging (MRI) or computerized tomography (CT) scan. The scan is used to diagnose certain health conditions, check on an existing condition, and plan and confirm treatment.

A person’s doctor generally requests a PET scan, and a person can check if the radiologist is accredited by using this online tool.

What is it used to detect?

Doctors use PET scans to detect the following:

A PET scan can detect issues with oxygen intake, metabolism, and blood flow, and may show if cancer has spread or reoccurred. Doctors may also use PET scans to verify whether cancer treatment is effective.

Can everyone have a PET scan?

While a PET scan involves ingesting or coming into contact with radioactive tracers, exposure to radiation is minimal. However, some people may have an allergic reaction to the tracers.

If a person has allergies to certain substances, including aspartame, saccharin, and iodine, they should tell their doctor before the test.

In addition, a person who is pregnant or breastfeeding, or has claustrophobia, may want to talk to their doctor before taking the test.

What to expect in a PET scan

When a doctor orders a PET scan, they will provide the person with instructions on how to prepare for the examination. Preparations for the two types of PET scans are different, and a person will need to confirm details with their doctor.

However, some instructions may include avoiding strenuous activities 24–48 hours beforehand and avoiding sugar and carbohydrates. In addition, a person may be asked to avoid eating at least 6 hours before a PET scan, although water is generally allowed.

A person with diabetes will receive special instructions since fasting before testing may negatively affect their blood sugar levels.

Accessories such as jewelry or piercing may interfere with the PET scan, and should be removed before the scan. However, medically approved devices, such as pacemakers and artificial joints, should not interfere with the procedure.

Medicare is a federal health insurance program.

  • Part A is hospital insurance, including hospice care.
  • Part B is medical insurance, including medical supplies and doctor appointments.
  • Part C, also known as Medicare Advantage, provides the same coverage as original Medicare (Part A and Part B), and may also offer additional benefits.
  • Part D covers prescription drugs.

A person may get coverage from various Medicare parts, depending on certain conditions.

Part A

If a person gets a PET scan while temporarily staying in a nursing facility or during a hospital stay, Medicare Part A may provide coverage.

Part B

Because Medicare Part B covers medically necessary services, including outpatient treatments, it may cover PET scans as diagnostic, non-laboratory tests.

To qualify for coverage, a doctor must order the test, and it must be medically necessary. A person can use this online tool provided by the National Coverage Determination (NCD) for PET Scans to find out if a condition qualifies as medically necessary.

Part C (Advantage)

Medicare-approved private insurance companies offer Medicare Part C plans, also known as Medicare Advantage. The plans must offer the basic coverage of original Medicare, parts A and B, and may also offer benefits such as dental coverage.

A person can check with their plan provider to find out if they have coverage for a PET scan, either to diagnose a condition or check on an existing one.


Medigap is supplemental insurance designed to provide coverage for additional costs not covered by original Medicare, including deductibles, copayments, and coinsurance.

There are different costs associated with the various Medicare parts.

Part A

Generally, a person does not pay a premium for Medicare Part A. It is often regarded as a premium-free plan because the costs are covered by payroll taxes. There are exceptions:

A $259 premium will apply for 2021 when a person paid tax for between 30–39 quarters.

A person who paid tax less for than 30 quarters will pay a premium of $471 in 2021.

People who qualify for this include those aged 65 and older who:

  • already receive retirement benefits from the Railroad Retirement Board or Social Security
  • had or had a spouse with Medicare-covered government employment
  • are eligible for Railroad or Social Security benefits but have yet to enroll

Part B

A person enrolled in original Medicare Part A can also get Part B benefits.

The Part B premiums are automatically deducted if a person gets benefit payments from the Railroad Retirement Board, the Office of Personnel Management, or Social Security.

In 2021, the Part B premium is $148.50 per month for a person with an income of $87,00 or less, with an annual deductible of $203. After meeting the deductible, a person will generally pay 20% of Medicare-approved costs.

Part C (Advantage)

The cost for Part C (Advantage) plans depends on various factors, including the plan provider and the plan a person chose. Some plans have zero premiums, but a person has to pay the Medicare Part B basic premium of $148.50 in 2021. A person with an income above $8,700 may have to pay higher premiums.

According to the Kaiser Family Foundation (KFF), the average out-of-pocket limit in 2019 was $8,649 for both out-of-network and in-network services and $5,059 for in-network services


A person enrolled in original Medicare, parts A and B, can also have a Medigap plan. The plans generally cover the out-of-pocket Medicare costs, including deductibles, coinsurance, and copays. However, Medigap plans do not cover the Part B deductible, as of 2020.

Original Medicare and Medicare Part C (Advantage) plans may offer coverage for PET scans. A doctor must order the PET scan, and it must be for a medically necessary reason.