PET CT scan and MRI are two major imaging diagnostic procedures which are used for the detection of abnormalities in the body. Both these imaging techniques used different set of principles for the detection of abnormality in...
PET CT scan and MRI are two major imaging diagnostic procedures which are used for the detection of abnormalities in the body. Both these imaging techniques used different set of principles for the detection of abnormality in the body. PET CT scan is more advanced than MRI scan as the test used radioactive tracer for the detection of abnormalities in the body. The major advantage of PET CT over MRI scan is that it is used to detect the cancer at very early stage of metabolism, when even symptoms are not clear or visible to the patient. Whereas MRI scan uses the principle of magnetism for detection of abnormality. MRI uses magnetic field to create the images of abnormality. Magnetic waves can displace metallic implants so it is not feasible for patients with metallic implants in the body. PET CT scan uses radioactive tracer, which may cause allergies in some patients and also exposes patient to the radiations.
What is PET CT?
PET CT scan is the combination of Positron Emission Technology (PET) and Computed Tomography (CT) for creating images to detect abnormalities in the body. PET CT scan uses radioactive tracer like FDG (Fluorodeoxyglucose) which can detect abnormality at the metabolic level. Radioactive tracer highlights the abnormal cells, which consumes more glucose comparing normal cells. CT helps to create the images of the condition and helps to detect the area suffering cancer condition.
Main Uses of PET CT:
- Helps to detect cancer in any part of the body
- Helps to detect the stage of cancer
- Helps to monitor the cancer before and after treatment
- Evaluating heart function and blood flow
- PET CT is very helpful in detecting neurological diseases like epilepsy, Parkinson’s and Alzheimer
What is MRI?
MRI is another imaging diagnostic procedure that used different principle for diagnosis comparing PET CT scan. MRI uses magnetic waves for the detection of abnormalities in the body by highlighting the anatomy of the site. MRI also uses contrast material in some cases to detect the condition more accurately and easily. MRI has the advantage over PET CT of not exposing patient to harmful radiations.
Main Uses of MRI:
- MRI is very useful in soft tissue abnormalities like Brain, muscles and tissues.
- Helps to imaging brain after stroke.
- Help to detect multiple sclerosis.
- Helps to evaluate different kinds of tumors
- Spinal cord evaluation.
- MRI is useful in imaging joints, cartilage and ligaments.
- Imaging of organs present in abdominal cavity.
- Imaging heart abnormalities like blood vessels and associated tissues.
|
S. No. |
Feature |
PET CT Scan |
MRI Scan |
|
1. |
Technology Used |
X-rays with radioactive tracer |
Magnetic field with radiofrequency waves |
|
2. |
Information Provided |
Metabolic activity, functional process and anatomical detail |
High resolution structure and soft tissue details |
|
3. |
Radiation Exposure |
Exposure of radiation due to CT scan and radioactive tracer |
No radiation used |
|
4. |
Best For |
Cancer, Metastasis, Treatment, Active diseases |
Brain, Muscles, Ligaments, Tissues |
|
5. |
Duration |
40 to 70 minutes |
30 to 90 minutes |
|
6. |
Preparation |
Requires fasting and radioactive injection is needed |
Patient need to remove metallic objects |
|
7. |
Safety |
Radiation exposure, not suitable for pregnant women |
Not applicable for patient with metallic implants like pacemaker |
|
8. |
Detection |
Early detection at metabolic level before structure changes appear |
Detects structural changes |
|
9. |
Cost |
More expensive |
Expensive and depends on body part to be scanned |
|
10. |
Availability |
Limited Availability |
More widely available comparing PET CT |
When Doctors Recommend PET CT
- Suspected Cancers
- Spread of confirmed cancers
- To check if cancer has spread.
- To look for treatment response
- To detect recurrent tumors.
- To detect neurological abnormalities
- To assess heart abnormalities
When Doctors Recommend MRI
- To look for Imaging of brain in Detail
- To look for herniated discs
- To look for spinal compression
- To look for musculoskeletal structures like cartilage, ligaments, bones etc.
- Abdominal and pelvic organ evaluation
- To look for Cardiovascular diseases
Advantages of PET CT
- Detects metabolic changes early.
- Combines functional and anatomical imaging
- Excellent for cancer staging and monitoring
- Helps to detect metastases, which may be missed in CT or MRI
- Guides treatment planning for oncology patients.
Advantages of MRI
- No radiation exposure.
- Superior detail of soft tissues
- Safe for repeated scans
- Helpful in detecting CNS issues in Brain and spine
- Detect musculoskeletal structures in detail.
- Provides 3D imaging without contrast in some cases
Limitations of PET CT
- Radiation exposure to the patient
- High cost and limited availability
- Need radioactive tracer like FDG glucose
- Not suitable for pregnant patients
Limitations of MRI
- Time-consuming and noisy scan.
- Fear of closed spaces in some patients
- Not applicable for patient with metallic implants in the body
- More expensive than CT scans.
List of PET CT and MRI scans available at Ganesh Diagnostic Center
PET CT scans
-
Whole Body PET Scan (Book Now)
-
F-18 Choline PET Scan (Book Now)
-
FDG-PET Scan (Book Now)
-
Brain PET Scan (Book Now)
Click Here to look for more types of PET CT
MRI Scans
- MRI Head Screening (Book Now)
- MRI Screening of Brain (Book Now)
- MRI Screening Cervical Spine (Book Now)
- MRI Face & Neck (Book Now)
- MRI Lower Abdomen (Book Now)
Click Here to any type of MRI Scan
Conclusion
PET CT and MRI are advanced diagnostic procedures which provide images for the detection of abnormalities in the body. PET CT is more advanced, expensive and specific comparing MRI scan. The major advantage of PET CT over MRI scan is that it is used to detect the cancer at very early stage of metabolism, when even symptoms are not clear or visible to the patient. Whereas MRI scan uses the principle of magnetism for detection of abnormality. MRI uses magnetic field to create the images of abnormality. Magnetic waves can displace metallic implants so it is not feasible for patients with metallic implants in the body. There are various advantages and disadvantages of both these diagnostic procedures and doctor can prescribe the test depending on various factors.
Frequently Asked Questions Related PET CT vs. MRI
Which test is more specific PET CT or MRI?
PET CT is more specific comparing MRI scan.
Which test is more expensive PET CT or MRI?
PET CT scan is more expensive comparing MRI scan.
Which test is suitable for pregnant women PET CT or MRI?
MRI is suitable for pregnant women because MRI does not use radiation.
Which test is more suitable widely available PET CT or MRI?
MRI is widely available comparing PET CT scan.
