Magnetic Resonance Imaging (MRI) is a radiology process used to scan different parts of your body or your body as a whole, in order to study certain medical conditions. MRI scans use pulses of radio waves along with strong magnetic fields to generate pictures of the internal tissues and other body structures in detail. Scanning process can be performed for diagnostic and well as treatment procedures.
MRI Machine
The process of scanning in MRI test uses radio waves and magnetic fields. Magnetic field intensity is measured in terms of Tesla. MRI machines are differentiated based on their magnetic field intensity, i.e. their Tesla units. Patients are recommended MRI test type according to their requirements.
There are various types of MRI machines; however, each one of them has the same working pattern. Different MRI machines have different purposes though. Let us learn about each one of them in detail.
Open MRI
Open MRI machines have an open, flat table, having two parts of the machine below and above it. These parts of the MRI machine enclose magnets that are responsible to generate a magnetic field for the MRI mechanism. The table attached to the MRI machine is sliding in nature and passes through a large ring. As patients pass through this ring, images of the necessary body portion are captured and recorded.
An open MRI machine uses low intensity magnetic fields. The structure of the machine of an open MRI is designed in such a way that it makes patients more comfortable while the procedure is going on. You can opt for an open MRI method if you are claustrophobic or have any other anxiety issues.
Closed MRI
The main difference between an Open MRI and Closed MRI is the structure of the machines. A closed MRI uses a large cylindrical tube in place of a ring. This tube generates a strong magnetic field and radio waves to image the internal structures of the patient’s body. During the scanning process, patients lie down on a sliding table that passes through this cylindrical container.
There are many sub-types of a closed MRI machine. These types of closed MRI test depend on the level or intensity of magnetic field used. Also, each one of these have different purposes in the medical field.
- 3 Tesla MRI
A 3 Tesla MRI is one of the types of a closed MRI. Compared to the other methods of MRI test, a 3 Tesla MRI uses magnetic field intensity double times as that of the conventional ones. It generates images of higher resolution due to the higher level of magnetic field it utilizes. Therefore, a 3T MRI scan is recommended to visualize minute details of the internal body structures.
A 3 T MRI scan is usually suggested to identify signs or symptoms of various diseases. It can also be performed to monitor progress of many treatment procedures. The advantage of 3 T MRI test is that it gives faster output as compared to the other mechanisms.
- 1.5 Tesla MRI
As the name suggests, this type uses 1.5 Tesla of magnetic field unit. It can be suggested for superficial structures of the inside of your body. Patients who cannot be subjected to a higher intensity of magnetic field can opt for 1.5 Tesla MRI instead of a 3 Tesla MRI scan test. Doctors will suggest you the right type of MRI scans based on your health condition.
There are many MRI mechanisms that use magnetic field strength such as 1.2 Tesla or lower strength of magnetic field. Magnetic field strength power can be in the range of 0.5 Tesla to 3 Tesla, that includes different applications and usage.
Cost of MRI Scans
The cost of MRI scans depends on various factors like magnetic field intensity of the MRI machine, type of MRI scan, etc. There can be variations in the cost of MRI depending on its factors as well as the facilities offered at radiology centers.
The cost of MRI scans is between the range of INR 2000 to INR 27,000.
Tesla Power
MRI procedures use different Tesla powers for different medical requirements. As mentioned earlier, Tesla is the unit to measure the magnetic field strength. More the magnetic field strength, better the resolution of the images we can get from this scanning test. However, doctors need high resolution scanned images only when they want to learn about minute structures of the inside of the body. Therefore, based on the health condition of the patients and their requirements, doctors decide which MRI technique is right. Tesla power plays a major role in the scanning process.
Properties of Tesla Power
MRI machines are distinguished as per the magnets used in their systems. Each magnet having a certain power of Tesla, serves a purpose in medical study. Based on the MRI Tesla power, its properties vary. For example, if you have a MRI machine with 3 Tesla power, it will provide you clearer images of the soft tissues and nerve structures than an open MRI machine. A 3 T MRI machine uses 10 to 15 times the intensity of the magnetic field than an Open MRI.
Higher the magnetic field strength, better the imaging. However, for many medical cases like pregnancy, patients cannot undergo an MRI procedure that has a high magnetic field intensity. Using a higher Tesla power in such patients can create health complication and risks.
Why is MRI Done?
As mentioned before, MRI scans are mainly conducted to learn about minute details of the internal structures of the patient’s body. In comparison with other imaging methods like X-rays, MRI scan procedure has a safety margin. An X-ray scan test has ionizing radiations that could cause health risk and complications. Therefore, it cannot be suggested to patients who are pregnant, those with thyroid disorders, etc. Whereas on the other hand, MRI is safer for such patients.
Pregnant mothers can undergo MRI of low magnetic field intensity. It is a safe and painless procedure for such medical cases. MRI scans are best for analysis of soft tissues unlike that in X-rays and CT scans, that cover hard body structures more easily.
MRI scans are more efficient in studying about deep structural anatomy of tissues and other body parts. Hidden structures, soft tissues, nerves, etc. can be easily detected and imaged using MRI scan techniques.
MRI can be suggested for the following reasons:
- Studying about the nervous systems
- Presence of internal injuries
- Studying certain brain or nerve functionality
- Swelling
- Inflammatory conditions
- Lesions
- Tumorous conditions
- Nerve blockages
- Accumulation of fluids in certain body parts
- Infections
- Abnormal structure of body or parts of the body
- Internal bleeding
- Study the changes after surgery
- Preoperative diagnosis and study
- Monitor progress of the results obtained from treatments
- Research purposes
- Congenital spine conditions
- Unexplained pain in certain parts of the body, eg. Back pain or headache
- Malformation of veins
- De-generative disorders
- Multiple sclerosis
- Hemorrhage
- Cancerous conditions
- Guiding tool for surgeries or interventions
- Fibrosis
Types of MRI Scan Tests
Types of MRI scans are classified depending on various factors like part of the body, purpose, magnetic field intensity, etc.
Extremity MRI
Extremity MRI is a closed MRI scanning process performed only to monitor the tissue bodies of your limbs. An extremity scanning machine is specially designed according to your limbs, consisting a smaller scanning tool. There is no requirement of enclosing patient’s entire body into the machine when imaging of your arms and legs are required. Therefore, for such cases, doctors recommend an extremity MRI procedure. It also avoids the claustrophobic situation for patients.
Doctors can suggest extremity MRI scan test for the diagnosis of the following health conditions related to your arms and legs:
- Fractures
- Tumor
- Arthritis
- Internal trauma conditions
- Nerve related problems
- Bone infections
- Inflammations
- Progress of certain treatment
Full Body MRI
Magnetic Resonance Imaging of the entire body is performed in order to take pictures of your internal body structures from head to toe. It takes around 45 to 60 minutes to record images of your complete body structures. There are many health conditions that can call for a full body MRI test.
To learn about a tumorous condition, your oncologist might ask you to undergo a full body MRI test. This test can provide your radiologist with the site of tumor. It can also show the number of tumors present in a patient suffering from advanced stage of cancer. There can be other health conditions that might need a full body MRI.
MRI of different sections of the body
MRI scan test can also be suggested for a particular section of the body, instead of undergoing a full body scan. Brain MRI, Lumbar Spine MRI, Dorsal Spine MRI, MRI of cervical regions, etc. are some of the types of MRI scans that are limited to a section of body parts.
MRI with or without contrast media
MRI techniques can also be divided into two types: MRI with contrast media and MRI without contrast media. The main purpose of using a contrast media in any imaging process is to get a clearer, visible structure of internal body structures. These materials are injected into your system through an intravenous point.
It is also used to study nerve damage and disorders. Blood clots, nerve decompression and many other issues related to the nerves can be easily detected under an MRI scan using a contrast media. They also include other applications like improve the quality of images of your body scan.
Most of the MRI scan techniques work without usage of contrast media. However, your doctor will give you all the instructions required if they are performing MRI using a contrast substance.
MRI as a guiding tool
MRI can not only be conducted for diagnostic purposes but also during a surgery. Surgery of internal hidden body parts can be easily detected under MRI process. Therefore, for such cases, doctors can operate your health disorder using an MRI at the same time. This combination of imaging and surgery increases the efficiency of the medical process being performed. Also, it provides better results when the surgery includes locating soft tissues.
MRI scans are also used along with biopsy procedures. Needle biopsy requires targeting lesions and learning about its exact location in order to collect tissue samples. Biopsy process involves collecting tissue samples for analyzing it under a microscope. Using MRI during a biopsy process can also help doctors set up a marker for further biopsy or interventional sessions.
Preoperative and Post Operative MRI
MRI is conducted for diagnostic purposes of the internal body parts. This scan test is also used to set markers at the site of operation to be performed, or future interventional sessions. MRI is also suggested to study, detect or locate a particular health problem that cannot be explained through other imaging tests.
Post MRI test sessions are mainly conducted in order to learn about the status of the ongoing treatment procedure. It can also be carried out to study about the results and recovery of an operated internal body part.
Note that before undergoing an MRI procedure, you must remove any sort of metallic accessories worn around your body. Metallic implants inside or outside your body can also be a trouble situation. Ensure you inform your doctor about them. MRI scanning tests disrupt the functionalities of metallic implants like pacemakers, stents, hearing aid, etc. due to the intense magnetic properties of the MRI machine.
To conclude, the above article encloses all the details about MRI scan examination. It enlists and explains about the type of MRI machines that are used for radiology purposes. You can also learn about Tesla power and how it affect your tests, why MRI scans are suggested and what are the different types of MRI scans available. Approximate range of cost of MRI scan test is also mentioned above.