3 doctors weighed in:

What is the difference between mris & pet scans?

3 doctors weighed in
Dr. Joseph Accurso
Radiology

In brief: Anatomy vs Physiolog

Mri and ct look at the structure of the body, the anatomy, and the way diseases change or distort it.
Pet looks at the physiology, or how the body uses, or metabolizes something. For pet, the most common metabolism pathway looked at is how glucose is used. A low dose ct is often acquired at the same time as the pet (as in pet/ct scan), to correlate the pet findings with the ct anatomy.

In brief: Anatomy vs Physiolog

Mri and ct look at the structure of the body, the anatomy, and the way diseases change or distort it.
Pet looks at the physiology, or how the body uses, or metabolizes something. For pet, the most common metabolism pathway looked at is how glucose is used. A low dose ct is often acquired at the same time as the pet (as in pet/ct scan), to correlate the pet findings with the ct anatomy.
Dr. Joseph Accurso
Dr. Joseph Accurso
Thank

In brief: Anatomy

Mri is a picture of structure or anatomy, and does well demonstrating brain pathology with changes in normal anatomy.
Pet scanning shows functional metabolic brain derangements, and can illustrate cancers, alzheimer's, various dementias, and abnormal brain handling of normal chemicals such as glucose. Pattens can be diagnostic.

In brief: Anatomy

Mri is a picture of structure or anatomy, and does well demonstrating brain pathology with changes in normal anatomy.
Pet scanning shows functional metabolic brain derangements, and can illustrate cancers, alzheimer's, various dementias, and abnormal brain handling of normal chemicals such as glucose. Pattens can be diagnostic.
Dr. Bennett Machanic
Dr. Bennett Machanic
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Dr. Maureen Nash
Psychiatry - Geriatric

In brief: Structure v Function

A pet scan tells us which cells are taking up glucose which is a measure of functioning.
Cancer cells take up too much glucose and other illnesses like dementia have cells that do not take up enough glucose. An MRI scan is a structural test and shows the outlines of cells and how big they are. Mri's are often most useful for looking at soft tissue.

In brief: Structure v Function

A pet scan tells us which cells are taking up glucose which is a measure of functioning.
Cancer cells take up too much glucose and other illnesses like dementia have cells that do not take up enough glucose. An MRI scan is a structural test and shows the outlines of cells and how big they are. Mri's are often most useful for looking at soft tissue.
Dr. Maureen Nash
Dr. Maureen Nash
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