- An MRI is a medical imaging modality that generates high-resolution images of soft tissues.
- A whole-body MRI scan shows the distribution of water molecules throughout your body.
- A whole-body MRI mainly uses diffusion images (DWI).
- MRIs are safe, painless, and do not use ionizing radiation.
Whole-body MRI (wb-MRI) is a medical imaging procedure that can detect cancer lesions and other abnormalities with high specificity in multiple organs.
The magnetic resonance imaging technique is considered safe because it is radiation-free. Other imaging modalities, like computed tomography (CT scan) and positron emission tomography combined with CT scan (PET/CT), use ionizing radiations. These can be harmful when the amount of radiation exposure accumulated in your body becomes too high.
How does a whole-body MRI work?
The way MRIs generate images is far more complicated than it is for CT scans and X-rays. Fully understanding it requires specific physics knowledge, but we’ll provide a brief overview here.
MR imaging uses a strong magnet and radio waves to create images. The protons in your tissues’ water molecules are aligned in an electromagnetic field. When the magnet stops, the protons return to their initial positions and emit radio waves.
The detector captures, computes, and transforms these radio waves into gray-scale images. The various gray shades are interpreted differently depending on which pulse sequences the radiologists use for your exam.
After reconstitution, the radiologists have a three-dimensional view of the patient’s whole-body MRI scan. The render is usually sliced into three conventional planes: sagittal, coronal, and axial. However, the radiologist can adjust the angles for a more optimal field of view.
What does a whole-body MRI tell you about your inner health?
Wb-MRI is a powerful technique that enables high-resolution images of soft tissues. Radiologists use various pulse sequences to generate a series of images. The contrast is based on the tissues’ protons’ time to get back to their initial positions.
Let’s cover the three types of whole-body MRI images:
- T1-weighted images show high-fat content tissues as bright. The high-water density areas appear dark. T1 images are usually used to demonstrate anatomical structures.
- T2-weighted images show high-water density areas as bright and high-fat content tissues as dark. This pulse sequence is great for detecting pathologies. Lesions or damaged tissues tend to release fluid and create edema.
- Diffusion-weighted images (DWI) are used routinely in MRI protocols. In fact, DWI is derived from T2-weighted images and is even better at detecting pathologies. DWI provides information about the diffusion of the water molecules inside and outside the cells. In oncology, the diffusion is directly related to the malignancy of tumors.
If you’d like to dig deeper on the subject, Dr. Padhani, a renowned oncologist, co-authored systematic review papers and other research papers published in Plos One and European Radiology (Eur Radiol) about DWI in cancer.
A whole-body MRI is recommended if you are at risk for developing cancer.
What are the cancer risk factors?
According to the American Society of Clinical Oncology, the general risk factors for developing cancer are:
- Age. The older you get, the higher your risk of cancer is. This is particularly true for prostate cancer.
- Genetics. If you have a family history of cancer, you have a high risk of developing cancer. For instance, the BRCA2 mutated gene‘s inheritance is a primary risk factor for breast cancer, uterus cancer, and prostate cancer.
- Tobacco consumption. Heavy smokers are at a high risk of lung cancer. Smoking contributes to 90 % of lung cancer deaths. Bladder cancer is not far behind either, as smoking results in toxins that your body tries to eliminate via urine. Quitting smoking cigarettes at any time, even if you are a long-time smoker, will help greatly to reduce the risk of cancer.
- Asbestos. This has been present in homes or constructions for decades. It usually rests in the wall or under the roof for insulation purposes. However, when disturbed, fine particles of asbestos are released into the air. This dust gets into your lungs and causes damages. Asbestos is a significant cause of lung cancer.
- Obesity. Being overweight and obese is linked to an increased risk of many cancers, including breast cancer, pancreatic cancer, colorectal, and thyroid cancers. The main cause is a chronic inflammatory state of your body. Staying at a healthy weight will typically reduce your cancer risk.
- Alcohol is a known risk factor for various cancers, such as cancers of the mouth, throat, and larynx, along with liver, esophageal, breast, and colorectal cancers. Two chemicals are responsible: ethanol and acetaldehyde, a product of alcohol degradation. These chemicals impair proper vitamin absorption, which will affect an organ’s ability to function.
- Viruses like human papillomavirus (HPV) lead to an increased risk of developing oral and cervical (uterus) cancers. The virus is generally spread by skin-to-skin contact. Indeed, vaccination is efficient against HPV, but it does not replace basic hygiene and cleanliness rules.
- Radiation exposure, especially to the sun, is the leading cause of skin cancer. Ultraviolet A (UVA) plays a role in skin cancer, and Ultraviolet B (UVB) is closely linked to sunburns, skin cancer, and melanoma. However, dermatologists recommend protecting yourself against both UVA and UVB from the sun to reduce your risk of cancer.
If you wonder whether you are at risk of cancer, ask your doctor. Additionally, Ezra’s 5-minute questionnaire can help to determine your risks.
How can you detect cancer at an early stage?
As you may have noticed, cancer could affect any part of your body. The only way to detect cancer at an early stage is to undergo regular checkups of your entire body—early detection can save you from more invasive treatments and improve your prognosis.
Stay alert for signs and symptoms of cancers. However, cancer symptoms usually appear at an advanced stage of the disease when the tumour is more difficult to eradicate and may have already metastasized to distant organs. That’s why you need help detecting cancer early.
How a whole-body MRI screening can help.
A whole-body MRI can thoroughly scan your body for signs of cancer. As mentioned earlier, an MRI can create high-quality images of the inside of your body.
This whole-body diffusion technique can help a radiologist see your full body’s tissue abnormalities, including lymph nodes or any nodules.
If your oncologist has any suspicion about whether lesions that appear on the scan are cancerous, they will prescribe follow-up exams and possibly a biopsy to improve their diagnostic accuracy and the characterization of the disease.
Additionally, bone scintigraphy could be performed to see the extent of cancer when looking for bone metastases in cancer patients. With its high sensitivity, this body imaging technique complements the whole-body MRI nicely.
Ezra’s whole-body MRI can help you stay healthy.
To keep our patients and staff safe, Ezra has considerable safety measures, including thorough cleanings between exams, social distancing in waiting rooms, and providing MRI-compatible masks that can be worn during the scan. We encourage you to get your annual cancer screening appointments back on your calendar.
Talk to your doctor and make an appointment today.