Your experienced medical expert has recommended you for knee magnetic resonance imaging. The diagnostic option uses magnetic fields, a computer, and radio waves to create cross-section (comprehensive images) slices of your knee. The images permit your physician to evaluate various body tissues like cartilage, tendons, ligaments, and meniscus and distinguish diseased tissues from healthy tissues. Los Angeles Diagnostics is a renowned diagnostic practice that uses state-of-art technology to help all patients and doctors make informed health care needs decisions. Whether you require diagnostic imaging to monitor your recovery journey following a surgical procedure, injury, or disease or make a diagnosis, we have the experience, knowledge, and equipment to get your answers effectively and efficiently.
Introducing a Knee MRI
Magnetic resonance imaging uses radio waves and magnets to get images in your body without any surgical incision. It could be performed on any body part. The knee MRI concentrates on the knee and the surrounding regions.
The examination allows your physician to see your soft tissues and bones. It permits them to inspect your knee elements that could be injured from gradual wear and tear or during physical activities. Moreover, the test offers comprehensive images of different knee sections, including blood vessels, ligaments, blood vessels, cartilage, bones, and tendons.
Your physician could order the scan if they think you have an abnormality in the knee joint, helping them determine the cause of the inflammation, weakness, or pain. Typically, the examination is performed to evaluate or diagnose:
- Knee weakness, swelling, bleeding, or pain the tissues around in your joint
- The damaged meniscus, tendons, ligaments, or cartilage
- Physical activities-related injuries like torn cartilage, tendons, or ligament and sprains
- Damage due to arthritis
- A bone fracture that is not visible on imaging tests like x-rays
- Fluid build-up in your knee joint
- Dead bone
- Tumor
- Knee cap pain and injury
- The reduced motion of your knee joint
- Infections
- Trauma or pain after a knee surgical procedure
- Complications associated with an implanted surgical device
The medical expert can also order the examination to check whether another surgery or knee arthroscopy is required or to monitor the progress following knee surgery.
How the MRI Scanner Looks Like
A conventional MRI unit is a cylinder-shaped tube with circular magnetic fields surrounding it. It has a table where the patients slide into the middle of the equipment.
Short-bore system MRI units are tailored that magnetic fields don't entirely surround the patient. Newer machines come with a bigger diameter bore that could be more comfortable for plus-size or claustrophobic patients.
On the other hand, open MRI equipment is open on its sides. It is beneficial for examining plus-sized patients and those with claustrophobia. While the unit can give high-quality images, the technician can perform only a few examinations with an open MRI. Please consult with your technologist to learn more.
Some imaging facilities use tiny scanners. In this case, you will sit or recline next to the scanner while only the body part being scanned is in the unit. These systems give high-quality images because of their powerful magnets.
How the MRI Procedure Works
Unlike computed tomography and x-rays examinations, magnetic resonance imaging doesn't use radiation. Instead, radio waves re-align hydrogen atoms in your body, causing no chemical change in your tissues. As your hydrogen atoms align back, they emit energy. The MRI scanner captures the energy, creating an image with the information.
Generally, passing electric currents via wire coils produce magnetic fields. Some coils are in the equipment, and others are placed around your knee. The coils send and receive radio waves and produce signals that the machine detects. You will not come into contact with electric currents.
The computer processes every signal and creates several images. Your radiologist can study the images from various angles.
MRI differentiates between normal tissues and diseased tissues better than ultrasound, CT scan, and x-ray.
When Should You Undergo an MRI Test of Your Knee?
An MRI plays a substantial role in assisting your physician in treating knee pain. When should you have the knee MRI? While an x-ray examination can show arthritis, it takes magnetic resonance imaging to tell if you have a torn meniscus or anterior cruciate ligament. Consequently, you should have your x-ray exam before the MRI; even when the condition fails to show up on the x-ray, the orthopedic surgeon will stage the level of arthritis to create the most appropriate treatment plans. If the condition is severe, you should have the MRI immediately. However, most patients can wait. The waiting duration depends on the x-ray examination results and whether the patient is above fifty-five years of age.
To tell if you require an MRI test, here is a brief background.
A meniscus is cartilage (horseshoe-shaped) between the shin and thigh bones. The thigh bones serve as the cushion while the meniscus absorbs shock in your knee and stops your bones from grinding against each other when you move. Your torn meniscus causes locking, popping, and clicking of your knee. Since the meniscus is made of cartilage and cartilage doesn't show on imaging tests like x-ray, your torn meniscus won't show after an x-ray examination. Fortunately, it shows clearly on magnetic resonance imaging.
An MRI is also instrumental in discovering a torn anterior cruciate ligament that is not shown on x-ray.
Inflammation on your knee causes arthritis. It can be due to osteoarthritis, an underlying rheumatoid aortitis, or trauma. Arthritis leads to thinning of your cartilage in rough surfaces, joints and loss of cartilage floating in your knee joint fluid. An MRI examination can identify these changes.
Suppose you have experienced knee deformity, a hot, red, swollen knee, unexplained weight loss, history of cancer, blood in the stool, vomit, or urine. In that case, your knee condition is severe, and you require an urgent MRI evaluation.
Since most knee conditions get better without any medical treatment intervention, if you haven't experienced any red flags within three weeks following your injury, the magnetic resonance imaging can wait. If the knee pain isn't improving on its own after three (3) weeks, you should visit your doctor. The physician will perform blood tests, x-rays, and a physical exam. The test results will determine whether you require the MRI exam.
Suppose you are above 55, the knee x-ray displays arthritis and without a torn ACL or meniscus. In that case, you have arthritis, you should begin rehabilitation sessions, and MRI isn't required.
Risks of Knee MRI
Since magnetic resonance imaging uses powerful magnets, metal in the body could be a safety risk if attracted to the magnet. If not attracted, the metallic substance could distort your MRI images. Before undergoing the examination, ensure you fill out a questionnaire and indicate whether you have any electronic device or metal in the body.
Unless you have a certified MRI safe device, you cannot undergo the imaging test. These devices include:
- Artificial heart valve
- Metallic joint prostheses
- Implanted heart defibrillators
- Implanted drug infusion pump
- Implanted nerve stimulator
- Pacemakers
- Metallic joint prostheses
- A metal clip
- Metal screws, plates, surgical staples, pins, or stents
- Cochlear implant
- Shrapnel
- Bullet
- Intrauterine device
If you have permanent makeup or tattoo, inquire from the doctor whether they can affect the procedure. Some dark inks have metallic elements.
When scheduling the examination, alert the physician if you are expectant. The impact of magnetic fields on your fetus is not well understood. The doctor might postpone the test or recommend alternative imaging tests. Also, remember to tell the doctor if you are a breastfeeding mother, mainly if you will receive a contrast agent during your medical imaging test.
It is also essential to tell the technologist and your doctor about liver or kidney challenges. These health conditions could restrict the use of a contrast agent during the examination.
How to Prepare for Your MRI Scan
Before your scan, you should change into a hospital gown. You can also put on your clothes if they are loose-fitting and don't have metallic fasteners.
Instructions about drinking and eating before your scan vary between facilities and examinations. Unless instructed otherwise, eat food and take your medications usually. However, the same is not true to oral gadolinium-based contrast agents, which you should stop drinking and eating at least four hours before your scan.
Sometimes examinations use an injection of contrast material. The technician will ask if you are asthmatic or allergic to drugs, environment, food, or iodine contrast material. If allergic to iodine contrast, the doctor can administer gadolinium. Even if you have an allergy to gadolinium, it can be administered following appropriate premedication.
Leave your accessories and jewelry at home. Alternatively, remove them before your scan. Electronic and metallic items aren't permitted in the examination room since they can interfere with the scanner's magnetic field. They can lead to burns or be harmful projectiles in the room.
It would help if you left the following:
- Hairpins
- Zippers
- Jewelry
- Watches
- Body piercings
- Eyeglasses
- Pocket knives
- Hearing aids
- Underwire bra
Tell your technician if you have any electronic or medical device in the body since they can pose a risk or interfere with your test. If you have a pamphlet of your implanted device, carry it to your examination.
If a loved one is accompanying you into the examination room, ensure they are screened for implanted devices and metallic objects.
Often children require anesthesia or sedation to complete a magnetic resonance imaging test without moving. It depends on your child's form of examination, intellectual development, and age. It would be best if an expert in pediatric anesthesia or sedation is present during the examination for the minor's safety. The doctor should advise you on how to prepare the minor.
Seasoned imaging facilities have experts who work with minors to assist in preventing the need for anesthesia or sedation. They show children a dummy scanner and play noise they will hear during the procedure. They will explain the medical procedure and answer all questions to relieve anxiety. Your child can watch their favorite movie while the scan is being carried out, aiding your child to stay still.
Finally, remember to carry:
- Your insurance card
- Photo ID
- An approved form of payment for coinsurance/copay costs.
What to Expect During the MRI Test
Typically, the scan is performed in outpatient hospitals and MRI clinics. The scanner is placed in its room within the imaging center. After ensuring you are safely in the machine, your radiologist will operate the scanner behind a glass partition. You can communicate through a two-way speaker system in the scanner.
Following filling out the appropriate paperwork and signing your consent form, a nurse or the technician will measure your height, weight, body mass index, blood pressure, and temperature.
When you go in for the scan, you will lie on a table and should remain still. The scanner moves as you are positioned to get clear images. The radiologist can request you to hold your breath at intervals for a couple of seconds. They will tell you when you could breathe again. The radiologist will issue the instructions over a microphone since they will collect your images in another room.
If your physician wants to take contrast magnetic resonance imaging, you will be injected with a contrast agent like gadolinium before your scan through an intravenous catheter in your vein. You could feel a cold sensation and sharp poke as the contrast is being absorbed into the bloodstream. If it injures you, notify the technician.
If your gadolinium-based contrast agent is oral, you will be given a few doses of the contrast agent to drink. While some have a sweet, syrupy taste, others are berry-flavored. It is normal to feel the urge to use the washroom or have a metallic taste in your mouth after drinking your dose. Nevertheless, if you experience stomach pain or nausea, notify the technician immediately.
The contrast agent is a rare earth metal that changes the contrast of your image. During your scan, the material lights up, allowing physicians to have an improved look at the knee. It could help them in the diagnosis of conditions like cancer and inflammatory ailments.
You might feel any of the following effects after your doctor injects the contrast dye into the IV line:
- Flushing sensation or a feeling of coldness
- A salty or metallic taste in the mouth
- A headache
- Vomiting and nausea
- Itching
Generally, these effects do not last for long. If they fail to go away or get worse, contact your doctor.
If you are a breastfeeding mother and had a contrast injection, it is advisable to feed your child again after twenty-four to forty-eight hours. Nevertheless, the American College of Radiology indicates that it is safe to breastfeed immediately after contrast injection.
During your scan, you will hear noises, and the radiologic expert will give you instructions. The noises are normal, and you'll be given headphones that play music during the scan. Moreover, you will feel a little warmth during your scan.
Your technician could use straps or pillows to make the knee more comfortable during your test. It will help to keep the leg still so the scanner can capture clear images.
If you cannot remain still, feel nauseated, or are cramping, let your technician know. It's okay to stop and rest for a while before proceeding.
Typically, the test will take between thirty minutes to one hour. After the medical expert has recorded the images they require, you can put on your clothes. A medical expert might want to check if you have any ill effects before allowing you to return home.
If a sedative was used, you will be taken to a recovery room and monitored until you can sit steadily. You will require a person to take you home.
How to Read Your MRI Results and Radiology Report
Your physician will use your knee MRI results to diagnose and treat your health condition. The radiologist will supervise your examination, read, and interpret the images before writing a report and sending it to your referring doctor. The report might have complicated medical information and words. If you have any questions, speak with the radiologist or doctor.
You can read your electronic health records, including the knee MRI results, online. Access to the health record might help you make rational decisions concerning your health. You can also electronically share the results with other medical experts, increasing your care's safety, efficiency, and quality.
Your MRI report should include the following sections:
Type of the Examination
The section contains the type, time, and date of the examination.
Clinical history
The section has personal details like gender, age, and any known health condition. It also answers your doctor's question. If your radiologist suspects a diagnosis, he/she will highlight it here.
Comparison
Your radiologist will compare your current knee MRI exam with your previous tests. Usually, comparisons involve tests of the same exam type and body area.
Technique
The section discusses how the knee MRI was conducted and whether the technician used a contrast agent. The information is helpful if any imaging test is required in the future.
Findings
The section discusses what your radiologist saw in your knee. They will indicate whether they consider your knee to be abnormal, potentially abnormal, or normal. If your report doesn't discuss any findings, it is because your radiologist didn't find any problem.
Impression
The section outlines your symptoms, signs, reasons for the knee MRI, clinical history and gives a diagnosis to elaborate the underlying challenge. It offers essential details for making decisions.
For abnormal findings, the radiologist might recommend:
- Biopsy
- Integrating the findings with lab test results or clinical symptoms
- Comparing your findings with previous imaging tests
- Further imaging
For potentially abnormal findings, your radiologist can make one of the mentioned above recommendations.
Find an Affordable MRI in Los Angeles
MRI is an invasive method to view your knee and its surrounding regions. Thanks to its strong radio waves and magnetic fields. Unlike CT scans and x-ray, an MRI scanner produces cross-sectional, 3D images of your knee without using radiation. Generally, doctors use MRI to view areas that are difficult to see using other imaging options.
Los Angeles Diagnostics offers advanced imaging technology. Our radiologists and technicians are certified and trained in interventional radiology and diagnostic procedures. The images we produce can help your doctor diagnose and treat your knee issue. We want the imaging test experience to be as enjoyable and comfortable as possible. Consequently, we are committed to treat you with compassion and respect and produce quality images and interpretation timely. For more information on how we can help you, contact us today at 323-486-7502.
