MAGNETIC RESONANCE IMAGING
MRI of the brain is very sensitive for assessment of abnormalities and may detect findings not visible with CT. Typical indications for an MRI of the brain include headaches, dizziness, visual changes, hearing loss, seizures, nausea, history of cancer, autoimmune disease and tingling or numbness in extremities. MRI of the brain can help detect strokes, vascular abnormalities, tumors and other lesions, metabolic disorders and multiple sclerosis or other demyelinating processes and Lyme disease.
MRI of the spine provides excellent diagnostic characterization. Typical indications for an MRI of the spine include neck or back pain, numbness or tingling in extremities, history of cancer or injury 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 and myelopathy including multiple sclerosis.
Typical indications for an 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. MRI helps distinguish between lymph nodes and blood vessels.
MRI is able to evaluate the shoulder, elbow, wrist, hip and knee amongst other large and small joints and non-joint extremity anatomy with exquisite detail. Typical indications for an 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 (infection of bone) and structural changes. MRI detects fracture, bone bruise and other post traumatic injury as well as tumor that is not detectable by X-ray, CT or nuclear medicine.
MRI is excellent for evaluation of the ankle and foot. This is of utility for assessment of joint and soft tissue pain, swelling, weakness, decreased range of motion or mass as well as post traumatic findings. Detection of tendon, ligament, cartilage and soft tissue findings, arthritis, tumors, plantar fasciitis and osteomyelitis as well as post surgical anatomy amongst other considerations may be imaged.
With the advent of breath hold imaging techniques and new equipment (coils), MRI is excellent for evaluation of the liver, spleen, kidneys, adrenal glands and pancreas. Typical indications for an 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.
In women, MRI of the pelvis is increasingly used to evaluate the uterus, cervix and ovaries. In men, MRI of the pelvis is increasingly used to evaluate the prostate, bladder, penis and scrotum. MRI of the pelvis can help detected enlarged lymph nodes, fibroids, ovarian cysts and masses, assess pain metastatic disease, evaluate testicular, prostate, uterine and ovarian cancer and assess structural abnormalities.
MRI is excellent for evaluating the blood vessels in the chest as well as lymph nodes, mediastinal nodes and the brachial plexus and muscles. Typical indications for an MRI of the thorax include history of a questionable mass, lymphoma, cancer, aneurysm or blood vessel abnormality. MRI of the chest can help detect metastatic disease, aortic aneurysms and aortic dissections.
Typical indications for MRI of the heart include congenital and acquired heart disease. Patients may be referred secondary to chest pain, valvular disease, history of a heart attack or possible heart attack and for assessment of heart function and structure. Cardiac gating reduces heart motion and allows visualization of heart structures.
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 a newer technique that may be used in addition to mammography and ultrasound.
MRI is able to evaluate the blood vessels non-invasively. This technique is known as MR angiography (MRA). MRA can evaluate blood vessels of the head and neck to detect vessel narrowing (stenosis), blood vessel blockage, cerebral aneurysm, arteriovenous malformation (AVM) and blood vessel dissection. This technique may be utilized for evaluation of both arteries and veins.
Contrast enhanced MRA utilizes an intravenous injection of MRI contrast media (Gd-DTPA). Blood vessels of the body including the aorta, neck arteries, organs and extremity arteries may be imaged as may the veins. This safe technique does not require hospital admission or arterial injection, unlike conventional angiography.