PET-MRI is a hybrid imaging technique utilising the functional uptake information of PET with the anatomical and soft tissue detail of MRI (magnetic resonance imaging).The availability of PET-MRI remains limited, largely due to the costs and expertise required. PET-MRI acquisition times are longer than those experienced with PET-CT. PET MRI scan offers a lower ionising radiation dose alternative with higher detection rates in a variety of studies when compared with PET CT hybrid imaging technique.
Benefits of PET-MRI Hybrid Technique?
- PET-MRI benefits to paediatric patients who have chronic inflammatory conditions or malignancy, where serial follow up examinations following therapy are required.
- Another benefit of PET-MRI include improved image alignment due to simultaneous acquisition of PET and MRI images,
- superior soft tissue contrast to PET-CT and ability to use MRI contrast agents.
When is PET-MRI Used?
Current applications of PET-MRI include
- Head and neck cancer
- Pelvic malignancies including prostate, rectal, ovarian, cervical and endometrial cancers.
- Lung cancer particularly for evaluation of brain metastases and local invasion in thorax
- Hepatobiliary cancers (primary and secondary)
- Multiple myeloma
- Lymphoproliferative disorders, particularly for detection and staging of diseases
- Infectious and inflammatory disorders
- Neurological conditions such as temporal lobe epilepsy.
- As a part of a research project
What to Prepare Before Your Scan?
- Eating and Drinking – you should stop eating 4-6 hours before the PET-MRI scan but you can drink during this time. Otherwise instructions are to be given by the hospital and your doctor depending upon the situation.
- Exercise– you might be guided to not exercise heavily 24 hours prior to the test
- Anxiety and claustrophobic– some people have a fear of closed spaces and crowded spaces which is known as being claustrophobic. You should tell your care provider beforehand if you have such anxiety triggering conditions.
- Pregnancy– you should inform your doctor and hospital about your pregnancy and if you think you might be pregnant before hand only as i is not safe to expose the unborn child to radiations unnecessarily
- Safety Checklist– because PET-MRI scan uses strong magnets which could affect any metal in your body so you should tell if you have any of the-
- Pacemaker or an implantable defibrillator
- Cochlear implants
- Metal fragments anywhere in your body- such as from injury
- Surgical clips, pins, or plates
What happens After The PET-MRI Scan?
- After the scan, you get up and sit comfortably
- You might have to stay in the hospital for 15 minutes so the staff can make sure there are no problems caused due to contrast medium.
- Then your iv cannula will be removed
- You are then free to go home.
- You can drink and eat normally after that unless otherwise guided
- Drinking plenty of water helps drain contrast at faster rate
- If you were given sedatives, you won’t be able to drive so need to be taken home by somebody else.
A PET-MRI scan is generally conducted under standard protocols and have very limited precautions and safety measures. Which may include the following
- Pregnancy- radiations usually can harm the unborn child so the scan should be done only in case of emergency and after a proper prescription of your doctor during pregnancy.
- Breastfeeding– you usually need to not feed your baby for at least 1 2 meals since the radiations take a little time to waveoff completely from the body also the tracer/contrast also takes few hours to get completely washed out from the body.
- Radiation– exposure to radiation during PET MRI scan can sightly increase you risk of developing cancer in future. You should talk to your doctor if it worries you.
- Kidney problems– there is a minimal risk that the contrast medium can affect your kidneys. Your radiographer checks your recent blood test results before your scan to make sure your kidneys are working well
- Bruising and swelling– You might get a small bruise around the area where your radiographer puts the cannula in. There is a risk that the radioactive tracer or contrast will leak outside the vein. This can cause swelling and pain in your arm but it’s rare and will get better quickly. Tell your radiographer if you feel any pain or swelling around the site.
- Allergy– Rarely, people have an allergic reaction to the contrast medium. This can start with a rash, weakness, sweating and difficulty breathing. Tell your radiographer immediately if you feel unwell so they can give you medicine to help. Or tell them before you have the contrast if you have had an allergic reaction to it before.
It is always better to get diagnosed early than later. Once your PET MRI scan or other x ray scans is taken, you usually wait for the report. We can shorten our waiting time by choosing a diagnostic centre nearby which provides digital reports. One of The best PET scan centres in Delhi is Ganesh Diagnostic and Imaging Centre.