Whats the Difference Between a PET Scan and CT Scan

What’s the Difference Between a PET Scan and CT Scan?

CT scans and PET scans focus on different aspects of the human body and use unique materials to do so, but they still share a lot in common. Similarities between CT scans and PET scans include:

  • Both are usually performed at an outpatient facility and do not require a hospital stay.
  • Both are common scans to detect cancer and cancerous cells.
  • Both are accurate, painless, and noninvasive procedures.
  • Both help eliminate the need for exploratory surgery.
  • Both sometimes use a contrast dye* to better define certain structures and increase the odds of seeing certain abnormalities, such as tumors or blood clots. If you have had an allergic reaction to iodinated contrast, your doctor will order your test without contrast, order a different kind of test like an MRI. 

*Iodinated contrast is generally considered safe unless you have had an allergic reaction or you have chronic kidney disease.

Most importantly, both are diagnostic imaging tests that help doctors diagnose the cause of a patient’s symptoms. This allows doctors to effectively treat their patients and help them enjoy healthy lives.

The main difference between a CT scan and a PET scan is their focus. A CT scan creates a detailed non-moving image of organs, bones, and tissues. A PET scan, on the other hand, shows doctors how the tissues in your bodywork on a cellular level. Other differences include:

  • They use different materials: CT scans pass x-rays through the body to create CT images. A PET scan uses a radioactive material that emits energy. The energy is then detected by a special camera to produce images.
  • A PET scan is more time-consuming: A CT scan is performed in minutes. This makes it an excellent tool in emergency situations when doctors need to act fast. A PET scan could take 20 minutes to several hours, depending on a patient’s condition. In some cases, the procedure may be performed over several days.
  • Radiation does not stay in the body with a CT scan: After a CT scan, no radiation remains in the body. On the contrary, after a PET scan, radiation will remail in the body but only a small amount.
  • PET scans detect cancer earlier than other tests: Unlike other forms of imaging, a PET scan shows molecular activity and helps doctors identify diseases in the earliest stages. For this reason, a PET scan is a highly reliable tool for detecting diseases such as kidney cancer and cervical cancer. CT scans show signs of an issue after a disease begins to change the structure of tissues or organs and are better for knowing if cancer has spread in the body.
  • They have different rules for eating or drinking: For a CT scan, if your exam includes an IV injection of a contrast dye, you will be asked not to eat or drink anything for three hours before your exam. For PET scan, you are to not eat anything 6 hours before your appointment but drinking water is encouraged to ensure hydration for best test results.

It is a good idea to talk to our doctor to identify which scan is better suited for your needs. Deciding between a PET/CT scan often depends on factors out of a patient’s control such as if the goal is to find cancer, identify different treatments for cancer, which type of medical imaging insurance coverage is available.

To book a scan, visit us at Medmo.com. Medmo helps people schedule radiology imaging tests – such as MRI, CT scans, PET, and more – at nearby accredited centers and identify the payment solution that works best for them.

CT scans and PET scans focus on different aspects of the human body and use unique materials to do so, but they still share a lot in common. Similarities between CT scans and PET scans include:

  • Both are usually performed at an outpatient facility and do not require a hospital stay.
  • Both can be used to detect cancer.
  • Both are accurate, painless, and noninvasive procedures.
  • Both help eliminate the need for exploratory surgery.

Most importantly, both types of imaging tests help doctors diagnose the cause of a patient’s symptoms. This allows doctors to effectively treat their patients and help them enjoy healthy lives.

The main difference between a CT scan and a PET scan is their focus. A CT scan creates a detailed non-moving image of organs, bones, and tissues. A PET scan, on the other hand, shows doctors how the tissues in your body work on a cellular level. Other differences include:

  • They use different materials: CT scans pass x-rays through the body to create images. A PET scan uses a radioactive material that emits energy. The energy is then detected by a special camera to produce images.
  • A PET scan is more time-consuming: A CT scan is performed in minutes. This makes it an excellent tool in emergency situations when doctors need to act fast. A PET scan could take 20 minutes to several hours, depending on a patient’s condition. In some cases, the procedure may be performed over several days.
  • Radiation does not stay in the body with a CT scan: After a CT scan, no radiation remains in the body. On the contrary, a small amount of radiation may stay in the body for a short time after a PET scan.
  • PET scans detect cancer earlier than other tests: Unlike other forms of imaging, a PET scan shows molecular activity and helps doctors identify diseases in the earliest stages. For this reason, a PET scan is a highly reliable tool for detecting diseases such as kidney cancer and cervical cancer. CT scans show signs of an issue after a disease begins to change the structure of tissues or organs and are better for knowing if cancer has spread in the body.

To book a scan, visit us at Medmo.com. Medmo helps people schedule radiology imaging tests – such as MRI, CT scans, PET, and more – at nearby accredited centers and identify the payment solution that works best for them.

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