 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Double click to edit
What is an MRI scan ?
An MRscan I is a safe and painless test that can provide detailed pictures of organs and other structures inside your body.
An MRI ( magnetic resonance imaging) scan is a radiology technique that uses magnetism, radio waves, and a computer to produce images of body structures. The MRI scanner is a tube surrounded by a giant circular magnet. The patient is placed on a moveable bed that is inserted into the magnet. The magnet creates a strong magnetic field that aligns the protons of hydrogen atoms, which are then exposed to a beam of radio waves. This spins the various protons of the body, and they produce a faint signal that is detected by the receiver portion of the MRI scanner. The receiver information is processed by a computer, and an image is produced.
The image and resolution produced by MRI is quite detailed and can detect tiny changes of structures within the body. For some procedures, contrast agents, such as gadolinium, are used to increase the accuracy of the images.
INDICATIONS OF MRI
Brain
Typical indications for a MRI of the brain include headaches, dizziness, visual changes, hearing loss, seizures, nausea, history of cancer, auto-immune disease, and tingling or numbness in extremities. MRI of the brain can help detect tumors and other lesions, metabolic disorders, and multiple sclerosis or other demyelinating processes.
Neck
MRI helps distinguish differences between lymph nodes and blood vessels. Typical indications for a MRI of the neck include enlarged lymph nodes or a palpable mass. MRI of the neck can help detect tumors and other lesions, vascular abnormalities, and structural abnormalities.
Spine
Typical indications for a MRI of the spine include back pain, numbness or tingling in extremities, history of cancer, and loss of bladder or bowel control. MRI of the spine can help detect herniated or bulging discs, arthritic changes, tumors and other lesions, differences between a post operative scar or recurrent disc, and structural abnormalities.
Thorax (Chest)
In the past, it was difficult to obtain diagnostic pictures of the thorax with MRI due to heart and breathing motion. However, MRI has improved its capability to take pictures by using a set of cardiac leads to monitor heart rhythms and acquire pictures with a "snapshot" eliminating heart motion. Breath-hold imaging utilizes ultrafast techniques while a patient holds his/her breath to acquire motion free pictures. Typical indications for a MRI of the Thorax include history of cancer and a questionable mass. MRI of the Thorax can help detect metastatic disease, aortic aneurysms, and aortic dissections.[ Top ]
Cardiac (Heart)
MRI is currently improving methods for evaluating the heart. Cardiac Gating reduces heart motion and allows visualization of heart structures, but coronary arteries are still difficult to evaluate. Typical indications for a MRI of the heart include congenital and acquired heart disease.
Breast
MRI’s ability to differentiate water, fat, and silicone makes it the procedure of choice for evaluating silicone breast implants or residual silicone from removed implants. MRI of the breast for cancer detection or screening is currently being developed, but not yet accepted as the procedure of choice.
Abdomen
With the advent of breath-hold imaging techniques and new equipment (coils), MRI is increasingly used to evaluate the liver, spleen, kidneys, and pancreas. Typical indications for a MRI of the abdomen include history of cancer, pain, loss of organ function, bleeding, cirrhosis of the liver, and hepatitis. MRI of the abdomen can help detect enlarged lymph nodes, metastatic disease, tumors and other lesions, aneurysms, and structural abnormalities.
Pelvis
New equipment (coils) now available greatly improves imaging in the pelvis. In women, MRI of the pelvis is increasingly used to evaluate the uterus, cervix, ovaries, bladder, fetus, and placenta. In men, MRI of the pelvis is increasingly used to evaluate the prostate, bladder, penis, and scrotum. Typical indications for a MRI of the pelvis include cancer staging, pain, palpable masses, and pregnancy complications. MRI of the pelvis can help detect enlarged lymph nodes, fibroids, ovarian masses, prostate cancer staging, metastatic disease, testicular cancer, and structural abnormalities.
Musculoskeletal
MRI is able to evaluate the shoulder, wrist, knee, ankle, and feet with exquisite detail. Typical indications for a MRI of a joint or soft tissue include pain, swelling, weakness, palpable mass, or decrease in range in motion. MRI of the joints and soft tissue can help detect torn ligaments, torn cartilage, edema (swelling), arthritic changes, tumors, lesions, osteomyelitis, and structural changes.
MR Angiography (MRA)
MRI is now able to utilize the blood as its own contrast agent to evaluate the blood vessels of the head and neck. This technique is known as MR angiography (MRA). MRA can evaluate blood vessels of the head and neck without injecting the patient with a contrast agent. This non-invasive technique requires only one additional set of pictures taken in addition with a standard MRI exam. MRA of the head and neck can help detect vessel narrowing (stenosis), blood vessel blockage, cerebral aneurysm, arteriovenous malformation (AVM), and blood vessel dissection.
What are the risks of an MRI scan?
An MRI scan is a painless radiology technique that has the advantage of avoiding x-ray radiation exposure. There are no known side effects of an MRI scan. The benefits of an MRI scan relate to its precise accuracy in detecting structural abnormalities of the body.
Patients who have any metallic materials within the body must notify their physician prior to the examination or inform the MRI staff. Metallic chips, materials, surgical clips, or foreign material (artificial joints, metallic bone plates, or prosthetic devices, etc.) can significantly distort the images obtained by the MRI scanner. Patients who have heart pacemakers metal implants, or metal chips or clips in or around the eyeballs cannot be scanned with an MRI because of the risk that the magnet may move the metal in these areas. Similarly, patients with artificial heart valves, metallic ear implants, bullet fragments, and chemotherapy or insulin pumps should not have MRI scanning.
During the MRI scan, patient lies in a closed area inside the magnetic tube. Some patients can experience a claustrophobic sensation during the procedure. Therefore, patients with any history of claustrophobia should relate this to the practitioner who is requesting the test, as well as the radiology staff. A mild sedative can be given prior to the MRI scan to help alleviate this feeling. It is customary that the MRI staff will be nearby during MRI scan. Furthermore, there is usually a means of communication with the staff (such as a buzzer held by the patient) which can be used for contact if the patient cannot tolerate the scan.
How does a patient prepare for an MRI scan and how is it performed?
All metallic objects on the body are removed prior to obtaining an MRI scan. MRI scanning requires that the patient lie still for best accuracy. Patients lie within a closed environment inside the magnetic machine. Relaxation is important during the procedure and patients are asked to breathe normally. Interaction with the MRI technologist is maintained throughout the test. There are loud, repetitive clicking noises which occur during the test as the scanning proceeds. Occasionally, patients require injections of liquid intravenously to enhance the images which are obtained. The MRI scanning time depends on the exact area of the body studied, but ranges from half an hour to an hour and a half.
MRI Scan At A Glance
·MRI scanning uses magnetism, radio waves, and a computer to produce images of body structures.
·MRI scanning is painless and does not involve x-ray radiation.
·Patients with heart pacemakers, metal implants, or metal chips or clips in or around the eyes cannot be scanned with MRI because of the effect of the magnet.
An MRscan I is a safe and painless test that can provide detailed pictures of organs and other structures inside your body.
An MRI ( magnetic resonance imaging) scan is a radiology technique that uses magnetism, radio waves, and a computer to produce images of body structures. The MRI scanner is a tube surrounded by a giant circular magnet. The patient is placed on a moveable bed that is inserted into the magnet. The magnet creates a strong magnetic field that aligns the protons of hydrogen atoms, which are then exposed to a beam of radio waves. This spins the various protons of the body, and they produce a faint signal that is detected by the receiver portion of the MRI scanner. The receiver information is processed by a computer, and an image is produced.
The image and resolution produced by MRI is quite detailed and can detect tiny changes of structures within the body. For some procedures, contrast agents, such as gadolinium, are used to increase the accuracy of the images.
INDICATIONS OF MRI
Brain
Typical indications for a MRI of the brain include headaches, dizziness, visual changes, hearing loss, seizures, nausea, history of cancer, auto-immune disease, and tingling or numbness in extremities. MRI of the brain can help detect tumors and other lesions, metabolic disorders, and multiple sclerosis or other demyelinating processes.
Neck
MRI helps distinguish differences between lymph nodes and blood vessels. Typical indications for a MRI of the neck include enlarged lymph nodes or a palpable mass. MRI of the neck can help detect tumors and other lesions, vascular abnormalities, and structural abnormalities.
Spine
Typical indications for a MRI of the spine include back pain, numbness or tingling in extremities, history of cancer, and loss of bladder or bowel control. MRI of the spine can help detect herniated or bulging discs, arthritic changes, tumors and other lesions, differences between a post operative scar or recurrent disc, and structural abnormalities.
Thorax (Chest)
In the past, it was difficult to obtain diagnostic pictures of the thorax with MRI due to heart and breathing motion. However, MRI has improved its capability to take pictures by using a set of cardiac leads to monitor heart rhythms and acquire pictures with a "snapshot" eliminating heart motion. Breath-hold imaging utilizes ultrafast techniques while a patient holds his/her breath to acquire motion free pictures. Typical indications for a MRI of the Thorax include history of cancer and a questionable mass. MRI of the Thorax can help detect metastatic disease, aortic aneurysms, and aortic dissections.[ Top ]
Cardiac (Heart)
MRI is currently improving methods for evaluating the heart. Cardiac Gating reduces heart motion and allows visualization of heart structures, but coronary arteries are still difficult to evaluate. Typical indications for a MRI of the heart include congenital and acquired heart disease.
Breast
MRI’s ability to differentiate water, fat, and silicone makes it the procedure of choice for evaluating silicone breast implants or residual silicone from removed implants. MRI of the breast for cancer detection or screening is currently being developed, but not yet accepted as the procedure of choice.
Abdomen
With the advent of breath-hold imaging techniques and new equipment (coils), MRI is increasingly used to evaluate the liver, spleen, kidneys, and pancreas. Typical indications for a MRI of the abdomen include history of cancer, pain, loss of organ function, bleeding, cirrhosis of the liver, and hepatitis. MRI of the abdomen can help detect enlarged lymph nodes, metastatic disease, tumors and other lesions, aneurysms, and structural abnormalities.
Pelvis
New equipment (coils) now available greatly improves imaging in the pelvis. In women, MRI of the pelvis is increasingly used to evaluate the uterus, cervix, ovaries, bladder, fetus, and placenta. In men, MRI of the pelvis is increasingly used to evaluate the prostate, bladder, penis, and scrotum. Typical indications for a MRI of the pelvis include cancer staging, pain, palpable masses, and pregnancy complications. MRI of the pelvis can help detect enlarged lymph nodes, fibroids, ovarian masses, prostate cancer staging, metastatic disease, testicular cancer, and structural abnormalities.
Musculoskeletal
MRI is able to evaluate the shoulder, wrist, knee, ankle, and feet with exquisite detail. Typical indications for a MRI of a joint or soft tissue include pain, swelling, weakness, palpable mass, or decrease in range in motion. MRI of the joints and soft tissue can help detect torn ligaments, torn cartilage, edema (swelling), arthritic changes, tumors, lesions, osteomyelitis, and structural changes.
MR Angiography (MRA)
MRI is now able to utilize the blood as its own contrast agent to evaluate the blood vessels of the head and neck. This technique is known as MR angiography (MRA). MRA can evaluate blood vessels of the head and neck without injecting the patient with a contrast agent. This non-invasive technique requires only one additional set of pictures taken in addition with a standard MRI exam. MRA of the head and neck can help detect vessel narrowing (stenosis), blood vessel blockage, cerebral aneurysm, arteriovenous malformation (AVM), and blood vessel dissection.
What are the risks of an MRI scan?
An MRI scan is a painless radiology technique that has the advantage of avoiding x-ray radiation exposure. There are no known side effects of an MRI scan. The benefits of an MRI scan relate to its precise accuracy in detecting structural abnormalities of the body.
Patients who have any metallic materials within the body must notify their physician prior to the examination or inform the MRI staff. Metallic chips, materials, surgical clips, or foreign material (artificial joints, metallic bone plates, or prosthetic devices, etc.) can significantly distort the images obtained by the MRI scanner. Patients who have heart pacemakers metal implants, or metal chips or clips in or around the eyeballs cannot be scanned with an MRI because of the risk that the magnet may move the metal in these areas. Similarly, patients with artificial heart valves, metallic ear implants, bullet fragments, and chemotherapy or insulin pumps should not have MRI scanning.
During the MRI scan, patient lies in a closed area inside the magnetic tube. Some patients can experience a claustrophobic sensation during the procedure. Therefore, patients with any history of claustrophobia should relate this to the practitioner who is requesting the test, as well as the radiology staff. A mild sedative can be given prior to the MRI scan to help alleviate this feeling. It is customary that the MRI staff will be nearby during MRI scan. Furthermore, there is usually a means of communication with the staff (such as a buzzer held by the patient) which can be used for contact if the patient cannot tolerate the scan.
How does a patient prepare for an MRI scan and how is it performed?
All metallic objects on the body are removed prior to obtaining an MRI scan. MRI scanning requires that the patient lie still for best accuracy. Patients lie within a closed environment inside the magnetic machine. Relaxation is important during the procedure and patients are asked to breathe normally. Interaction with the MRI technologist is maintained throughout the test. There are loud, repetitive clicking noises which occur during the test as the scanning proceeds. Occasionally, patients require injections of liquid intravenously to enhance the images which are obtained. The MRI scanning time depends on the exact area of the body studied, but ranges from half an hour to an hour and a half.
MRI Scan At A Glance
·MRI scanning uses magnetism, radio waves, and a computer to produce images of body structures.
·MRI scanning is painless and does not involve x-ray radiation.
·Patients with heart pacemakers, metal implants, or metal chips or clips in or around the eyes cannot be scanned with MRI because of the effect of the magnet.
