Patient Blog

How to Read an MRI Report: T1, T2 Signal Intensity, Enhancement & More

Updated on: September 3, 2024 | PocketHealth
How to Read MRI Results - coronal and lateral of brain

If you’ve received your MRI results, you might be wondering what all the medical jargon, acronyms, and technical terms mean. It’s easy to feel confused. This guide will help you understand these specialized terms, such as orientation, signal intensity, and weighted images.

PocketHealth provides secure and easy access to your final report as soon as it is uploaded, giving you an early glimpse of your results. This allows you to familiarize yourself with your records, prepare questions for your follow-up appointment, and gain insights into your health. While it does not replace medical advice, it empowers you to have more informed discussions with your healthcare provider.

Get early access to your MRI images and reports

 

What does an MRI show?

Magnetic resonance imaging (MRI) is a medical imaging technique that creates comprehensive images of your internal structures. It utilizes radio waves and magnets to view details of organs, blood vessels, muscles and bones. Here are examples of some of the medical conditions an MRI might help diagnose:

  • Blood vessel restriction, Hemorrhages
  • Fluid build-up (e.g. in the spinal cord)
  • Neurological conditions (such as Multiple Sclerosis, Dementia, Stroke)
  • Cancer
  • Trauma or injury
  • Infection

Possible abnormal findings in MRIs may show the following:

  • Cyst: A cyst is a fluid-filled sac. Cysts usually do not present any symptoms.
  • Edema: An edema is inflammation or swelling caused by the build-up of fluid.
  • Lesion: A lesion is an informal term for any tissue abnormality. Lesions can be caused by illness, injury or even aging.
  • Mass: A mass is any unexpected tissue growth or volume.
  • Tumor: A tumor is a solid mass of abnormal cell growth. Tumors may be benign or malignant.

While it is understandable to feel nervous, abnormal findings don’t necessarily mean cancer or other serious conditions. It’s helpful to discuss any questions about your results with your doctor. Depending on the findings of your MRI scan, your healthcare provider may refer you for more imaging (such as a CT scan or ultrasound). Confirmation of your diagnosis may require a biopsy.

Report Reader is a valuable tool designed to empower you with a better understanding of your results. It translates complex medical terms into easy-to-understand language, enabling you to grasp the details and approach your next doctor’s appointment with confidence. The MyCare Navigator feature goes a step further by alerting you if your results indicate a need for follow-up, ensuring that you never miss an important discussion with your healthcare provider.

 

MRI views: Axial, Coronal and Sagittal

MRI with axial, coronal and sagittal views

MRI with axial, coronal and sagittal views

MRI images are taken from three different angles across various planes of your body. This approach ensures the most accurate and detailed images. These cross-sectional images provide the radiologist with a detailed 360° overview and are referred to as the orientation. The 3 cross-sectional orientations are:

  1. Axial view (or Transverse view): The axial view creates a horizontal image from the top of your body to the bottom.
  2. Coronal view: The coronal view is the frontal view, presenting a mirror image of your body from front to back.
  3. Sagittal view: The sagittal view is the side view of your body, creating a lateral image from the left of your body to the right.

 

T1 vs T2 on MRI: What is the difference?

MRIs showing the difference between T1 and T2 weighted scans

MRI scans showing the difference between T1 and T2 weighted scans

A T1-weighted MRI uses the rate of energy released as protons resume alignment (T1 relaxation) to create images. T1 images better show the anatomy of soft tissues of the body.

A T2-weighted MRI uses the oscillation of protons during the process (T2 relaxation) to create images. T2 images more accurately show the composition and placement of water molecules in tissue, highlighting cysts, fluids and swelling.

Together, T1 and T2 images provide doctors with complementary diagnostic information.

What does low T1 signal mean?

A low (hypointense) T1 signal compared to surrounding muscular or skeletal tissue often indicates bone lesions. The lesion area is generally compared to nearby structures and muscle to confirm the abnormality. A low T1 signal in bony areas can suggest increased water content and a decrease in normal fatty tissue. This can indicate conditions such as cancer, infections or trauma from an injury.

You may also come across terms like “diffusely low T1 marrow signal“. This typically indicates less fatty and more cellular or fluid-rich bone marrow. It could be due to anemia, infiltrative disorders like leukemia or metastatic cancer, inflammation, or changes from treatments like chemotherapy. The significance depends on the clinical context and should be assessed by a radiologist.

What does increased or high T2 signal on an MRI mean?

An increased or high (hyperintense) T2 signal can indicate a lesion in soft tissue. The tissue appears brighter than nearby areas, suggesting increased water content in these lesions. Possible causes of increased T2 signals include inflammation, cysts, abscesses, tumors and edema (areas of swelling).

 

What does signal intensity mean on an MRI?

Signal intensity is the level of brightness in an area of an MRI image. The variance in signal intensity can highlight the difference between an affected area and the surrounding tissue, leading to a successful diagnosis.

The level of signal intensity in an MRI image depends on the radiofrequency pulse used in the MRI machine, as well as the proton density and T1 or T2 qualities of various tissues.

What does low or decreased signal intensity mean on MRI?

What low signal intensity indicates depends on what pulse sequence is used. Fat, for example, is bright (meaning it has high signal intensity) in T1-weighted images. But fat and water and both are bright in T2-weighted images. Low signal intensity often means the area is darker compared to adjacent tissues, but there are many exceptions depending on the imaging method, such as T1 versus T2-weighted images.

For example, low signal intensity on T1-weighted scans can imply scar tissue, old hemorrhages or calcifications. On T2-weighted scans, this same low signal intensity can suggest certain tumors, dense tissue such as calcified lesions or iron deposits. It all depends on the imaging techniques and the makeup of the tissue or bone being scanned.

What does high or increased signal intensity mean?

High signal intensity is often white on an MRI image. As with decreased intensities, indications vary based on imaging techniques and the areas of the body being scanned. For example, on T1-weighted scans, tissues with fat, areas of increased blood flow and inflammation or tumors can show up brighter on the MRI. T2-weighted scans might indicate cysts, other tumor types or areas of swelling and fluid retention.

What is abnormal signal on MRI?

Abnormal signals on MRI results can indicate a variety of issues. These signals can appear in both bony structures and soft tissue, showing as increased or decreased brightness in certain areas or deviating in appearance compared to baseline images, usually from past scans of the patient when available. For instance, an athlete may experience increased wear and tear as they age, which could result in abnormal MRI findings compared to previous scans.

The range of possibilities with abnormal signals is vast, including cysts, tumors, inflammation, infection, arthritis and multiple other conditions, many of which are benign. Because of this, try not to panic if you receive an abnormal signal in your report. Your doctor will discuss whether any further testing is needed and share their thoughts on potential diagnoses.

What does fluid signal mean?

Fluid signals refer to fluid filled areas on the MRI. They typically look bright on T2-weighted scans but dark on T1-weighted scans. They are helpful for evaluating possible fluid-filled structures in the body, such as cysts, abscesses and edemas.

Fast and easy access to your MRI images and reports

What is contrast?

In MRI scans, a contrast agent is often used to enhance the visibility of blood vessels, organs, and soft tissues, making fine details more apparent. This agent, typically derived from gadolinium, is injected through an IV before the scan. By altering the magnetic properties of water in the body, the contrast agent improves the clarity and sharpness of the images, allowing for a more accurate diagnosis.

What does enhancement mean on an MRI?

Enhancement refers to the increase of signal intensity due to the absorption of the contrast agent. Areas of increased blood flow, such as tumors, also have increased uptake of the contrast material.

Here is some terminology regarding enhancement that you may encounter in your final report and what it means:

  • Abnormal enhancement: This refers to how tissues take up the contrast agent. If it reacts unexpectedly, it can help with diagnosis. For example, increased enhancement may point to inflammation while lower enhancement may point to low vascularity.
  • Mild enhancement: This indicates a slight increase in contrast uptake in a tissue, which may suggest mild inflammation, early-stage disease, or less aggressive pathology.
  • No enhancement: This refers to the absence of contrast uptake in a tissue, suggesting that the area is not vascularized or lacks abnormal pathology, often indicating normal tissue or non-active disease.
  • No abnormal enhancement: This refers to tissues not reacting unusually to the contrast agent. They are neither brighter nor darker than expected, which can often indicate the absence of conditions such as inflammation, infections or tumors.
  • Heterogeneous enhancement: This refers to uneven or varied uptake of the contrast agent in tissues, indicating areas with different densities or compositions, often associated with tumors, inflammation, or other abnormalities.
  • Patchy enhancement: This describes irregular, non-uniform areas of contrast uptake within a tissue, often seen in conditions like inflammation or infections where some parts of the tissue enhance more than others.
  • Peripheral enhancement: This refers to an increased pattern of contrast agent seen around the edges of abscesses, lesions, inflammation or other areas with some abnormality. This is helpful to determine the extent and behavior of the irregularity.

MRI report terminology: Findings, indication, impression and unremarkable

Here’s a quick guide to understanding key MRI report terms: findings, indication, impression, and unremarkable. This section will help clarify what your MRI shows and what it means for your health.

What does MRI findings mean?

The findings section of an MRI report details the observations made by the radiologist as they review the images. This part lists any abnormalities, changes, or notable features seen in the scanned area. It’s a descriptive section that records everything observed, even if it’s not necessarily related to the condition being investigated.

What does indication mean on an MRI report?

The indication section of your MRI report is a brief summary of the medical reason that necessitated the MRI in the first place. It is a way for the physician to communicate medical suspicions or symptoms to the radiologist who will interpret the images, providing them with a framework of your condition to keep in mind as they review your MRI.

What does impression mean on an MRI report?

In the context of an MRI report, the “impression” is the section where the radiologist provides a summary of the key findings and their interpretation. This part distills the complex imaging data into a clear, concise conclusion, highlighting any abnormalities or significant observations. The impression is typically the most important part of the report, as it gives the referring physician a clear understanding of what the MRI revealed and helps guide further diagnosis, treatment, or follow-up.

What does unremarkable mean in MRI results?

In MRI results, the term “unremarkable” means that the area being examined appears normal and shows no signs of abnormalities, disease, or any noteworthy findings. Essentially, it indicates that nothing unusual or concerning was detected in that specific part of the body.

 

How to read a brain MRI report

Doctor pointing out various MRI scans

Reading your brain MRI report is similar to what has already been discussed in this guide. However, it can be helpful to keep certain factors in mind as you review your results.

1. If applicable, look for a comparison to previous MRI scans

If you are having a repeat MRI to track progress on some condition or abnormality, your new MRI report will likely compare current findings to old findings.

2. Understand the differences between a normal and abnormal brain MRI

Some possible findings you may see in an abnormal brain MRI include:

  • Irregular light or dark areas (often referred to as lesions)
  • Irregular structures or growths
  • Edemas (indicating fluid buildup)
  • Swelling, masses, bleeding or other conditions

Remember, your MRI is a tool to help your doctor reach a diagnosis. It usually requires additional testing to pinpoint your condition, if any. It can be easy to worry about abnormal brain MRI results, but they are far more common than most people realize. Many irregularities turn out to be benign or easily treatable. Your doctor will be able to discuss any results that point to a normal versus abnormal brain MRI, as well as the next steps you may need to take.

3. Look for terms like brain, soft tissues and marrow

Depending on the extent of your brain MRI, there will likely be a section describing these areas. If they are described as unremarkable, they are within normal expectations. The radiologist will indicate if there are abnormalities. Also, there are brain-adjacent terms you may come across, such as sella and parasellar. These are anatomical descriptions of the area around the pituitary gland, which is located at the base of the brain. Your doctor will be able to help you understand where these areas are if you find yourself uncertain.

4. Learn what terms like pachymeningeal and leptomeningeal enhancement mean

You may come across terms like pachymeningeal enhancement, leptomeningeal enhancement, and intracranial enhancement when reviewing a brain MRI. Here’s what these terms mean:

  • Pachymeningeal Enhancement: This refers to the thickening and increased visibility of the dura mater (the outermost layer of the meninges) on an MRI, often due to inflammation, infection, or certain medical conditions.
  • Leptomeningeal Enhancement: This describes the enhancement of the inner layers of the meninges (the pia mater and arachnoid mater) seen on MRI. It can indicate inflammation, infection, or the spread of cancer to these layers.
  • Intracranial Enhancement: This term refers to the increased visibility of structures within the skull (intracranial structures) on an MRI after contrast is administered, often indicating abnormal blood-brain barrier permeability or pathology.
  • Dural Enhancement: Dural enhancement is a specific type of pachymeningeal enhancement that focuses on the dura mater. It typically suggests inflammation, infection, or metastatic disease affecting the dura.

5. Findings and impressions

These are some of the most important sections of your MRI report. They will include the radiologist’s determinations of your images. This may include specific measurements of any lesions or growths, descriptions of changes in your condition compared to previous MRI reports, or any other significant findings, theories or thoughts on diagnoses.

 

Confidence and self-advocacy: the importance of understanding your MRI results

Patient viewing their MRI results on PocketHealth’s online platform

Patient viewing their MRI report on PocketHealth

Waiting for MRI results can be nerve-wracking. More than 50% of patients say that waiting for the results of an MRI or CT scan induces anxiety. Understanding the findings in your MRI report can help reduce that anxiety, as can gaining faster access to your finalized results with PocketHealth. As soon as your report is officially uploaded, you can safely access it anytime you need. While the doctor who ordered the MRI will explain your report at your next appointment, getting an early view can help you prepare and make the most of your time together.

Fast and easy access to your MRI images and reports anytime.

 

How PocketHealth can help you access and understand your MRI report

With PocketHealth, you get fast and secure access to your MRI results from any device. You can easily view your MRI images and reports from any device, and even share them in diagnostic quality with specialists you want to obtain a second opinion. Jeanne found this especially important when she was abroad in Costa Rica and needed to see a local doctor for knee, hip and back pain. With all her old MRI scans and other imaging in one place, he was able to use them to give her a diagnosis and treat her pain, even when she was far from home.

PocketHealth Report Reader can help you better understand the findings in the radiologist’s report by providing easy-to-understand definitions of complex medical terms. MyCare Navigator detects and highlights follow-up recommendations and provides you with personalized questions to ask your doctor.

 

Related Posts

Access My Records