What is neuroradiology?
Neuroradiology is the subspecialty of radiology that conducts imaging of the brain and nervous system, head, neck and spine. Imaging methods used in neuroradiology include x-ray, CT, ultrasound and MRI.
How do X-ray exams work?
A radiograph, or X-ray, is the most common type of medical imaging. X-rays use a small amount of radiation to create pictures, or images, of the body’s internal structures. X-rays are noninvasive tests. Radiation dose is determined by type of exam and body area being imaged.
What is a CT scan?
CT, or computed tomography, takes multiple images in visual cross-sections inside the body. These pictures are made by special equipment during a CT scan or CAT scan, with small amounts of radiation. The CT scanner rotates around the examination table, taking pictures quickly and painlessly. A computer assembles those images into a multidimensional view.
Compared to regular x-ray images, CT images can show greater detail on soft tissue, blood vessels and organs. This is helpful for evaluating spinal pain, stroke symptoms, brain bleeds and tumors.
How does ultrasound work?
Ultrasound, or sonography, uses sound waves to create pictures of the inside of the body. It is a painless method of imaging the structure and movement of organs and blood flow. Gel is placed on the skin and an external probe is moved across the area to transmit and collect sound waves. A computer turns the sound waves into images. There is no radiation or x-ray exposure.
General ultrasound is 2D, or two-dimensional (flat). 3D ultrasound creates 3D images for specialized uses and 4D technology can animate 3D images. Doppler ultrasound examines blood flow in arteries, veins and blood vessels. Head ultrasound is used in premature infants and some adults having brain surgery. Transcranial Doppler ultrasound evaluates stroke risk and stenosis.
What is MRI?
MRI, or magnetic resonance imaging, creates detailed pictures of organs, soft tissue and bone. Images are made using a unit equipped with a powerful magnet and radio waves. There is no radiation or x-ray exposure. The examination table moves through the MRI unit, a large tube, as images are taken. High field MRI units with wider openings are available to create greater comfort for claustrophobic, bariatric or larger patients.
Many conditions may be diagnosed with MRI, including stroke, epilepsy, brain tumors, aneurysm, back pain and disk disease. MRI is highly sensitive for imaging the spine and its bones, ligaments and spinal cord. Functional MRI, or fMRI, can assess specific areas of brain function and evaluate the effects of stroke or degenerative disease.
What is nuclear medicine imaging?
These scans show molecular or chemical activity within the body, using small amounts of radiotracers, or radioactive material, that are swallowed, injected or inhaled. The material gradually flushes out of the body after imaging is completed. Nuclear medicine imaging modalities include positron emission tomography, or PET, and SPECT, single-photon emission-computed tomography.
Nuclear medicine can show blood flow problems in the brain, neurological disorders, tumors and spinal fluid leaks.
How should I prepare for neuroradiology imaging?
Preparation depends on the type of imaging you will receive. You will be told if you must not eat or drink for a few hours before the exam, or other instructions that could affect imaging results. It’s best to wear comfortable clothing without metal on it, although you may be given a gown to wear.
Who reads and evaluates the images?
A neuroradiologist, a physician trained in interpreting neuroradiology exams, will analyze the images and report findings to your doctor, who will discuss the results with you.