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RADIATION & PET/CT

Modern PET/CT, designed with you in mind.

PET/CT uses a small amount of radiation to create detailed images that help your care team diagnose and stage many conditions. At Shields, we use modern low-dose technology and careful protocols to get the information your physician needs—without using more radiation than necessary.

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LOW-DOSE APPROACH

Why PET/CT uses radiation—and how we keep it low

PET/CT combines two scans—PET and CT—to show both detailed anatomy and how tissues are functioning. PET uses a radiotracer (often called a “tracer”) that gives off a small amount of radiation so the scanner can create images. CT uses x-rays to provide detailed anatomical pictures. With our modern PET/CT technology and dose-optimized protocols, we achieve excellent image quality with a lower radiation dose than older systems.

Modern low-dose scanner settings help limit radiation while keeping images clear.
Standardized protocols support consistent quality and appropriate dosing.
Personalized scan parameters based on the tracer, body area, and clinical question.
Clear guidance after your scan (like hydration tips) supports normal tracer clearance.

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FAQs

Common questions. Answered simply.

Here are straightforward answers to common PET/CT questions—so you can feel informed and confident going into your exam.

Tracer:

A tracer (also called a radiotracer) is a small amount of material that acts like a marker in your body. It helps the scanner “see” how organs and tissues are functioning so your care team can get clearer information from the exam. The tracer is radioactive and specially designed for medical imaging so your body naturally clears it over time.

Radiation:

Radiation is what makes PET/CT imaging possible. PET uses the radiotracer signal to show tissue activity (function), and CT uses x-rays to show detailed anatomy (structure). Together, they provide a more complete view to support diagnosis, staging, and treatment planning for many conditions.

Radiation Amount:

The amount of radiation varies based on the tracer used, the body area being scanned, and whether the CT portion is low-dose (for localization) or a full diagnostic CT. Your physician orders a PET/CT when the medical benefit outweighs the small radiation risk. With modern PET/CT technology and dose-optimized protocols, we can achieve high-quality images using a lower radiation dose than older systems.

Radiotracer longevity:

No. The tracer naturally leaves your body over time—typically within hours. You may be advised to drink fluids after your scan to help your body clear it.

Pregnant or breast feeding patients:

Let your ordering provider and Shields team know before your exam. Depending on your situation and the reason for the scan, your care team may adjust the plan or timing, and we’ll guide you through next steps.

After your PET/CT scan:

You may resume normal activities after your exam. Drink plenty of fluids throughout the day to help flush the tracer from your body. As a safety precaution, please stay 6 feet away from children and pregnant women for 6 hours after your appointment. Results will be reviewed by a radiologist and shared with your referring provider within a few days.

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