Neuroradiology: Treatment, Effects & Risks

Neuroradiology visualizes neurological structures in the human body using the imaging techniques of sonography (ultrasound), computed tomography (CT), and magnetic resonance imaging (MRI). It is a subspecialty of radiology.

What is neuroradiology?

Neuroradiology visualizes neurological structures in the human body using the imaging techniques of sonography (ultrasound), computed tomography (CT), and magnetic resonance imaging (MRI). Neuroradiologists are specialists within radiology who have an additional qualification as neurologists. In Germany, only larger university clinics and hospitals have permission to offer advanced training in neurology. This specialty deals with the neuroradiological diagnosis of changes and diseases of the central and peripheral nervous system using induced radiation protection. For this purpose, physicians use diagnostic imaging techniques. Imaging procedures (ultrasound, X-ray, tomography) are cross-sectional images of a body part. In addition, interventional methods are available to this specialty for the elimination of detected diseases.

Treatments and therapies

Neuroradiology provides a pinpoint view of the human brain as well as the central and peripheral nervous systems. It is not only important in the area of diagnosis, but also finds use in gentle therapies. Through imaging diagnostics, the neuroradiologist can inject pain-relieving drugs through catheters or needles precisely to the affected areas. Many different diseases can be detected and treated by means of neuroradiology. If the patient suffers from back pain, painkilling drugs are injected into the spine through small needles under local anesthesia. Aneurysms (bleeding in the brain) are treated neurosurgically (invasive removal) or endovascularly (closure by catheter with platinum coils). In the case of a stroke, the disturbed blood supply to the brain is removed. A stent is placed from the groin through a catheter to dilate blood vessels or remove a blood clot. Neurologists detect and treat strokes, tumors (oncology), epilisia, Parkinson’s disease, dementia (Alzheimer’s disease), multiple sclerosis, cerebral hemorrhages, edema, vascular occlusions, vascular malformations, hemodynamically relevant vascular stenoses (internal carotid artery, carotid artery), thromboses and minute tissue changes. Modern neuroradiology is important in the early detection of dementia, because not all memory disorders are due to a dementia-like syndrome such as Alzheimer’s disease. Thus, neuroradiology can detect dementia diseases at an early stage, because unlike a stroke, in which the brain tissue is no longer supplied with blood and perishes within a few minutes, dementia builds up gradually and is often detected too late. Individual brain regions change negatively due to amyloid plaques (protein deposits), which cause nerve cells to die over a long period of time. In addition, neurofibrils (thread structures) form that disrupt brain activity. Although imaging techniques do not make these processes visible, they do allow a conclusive finding to be made. If a suspicious pattern of disease is present, functional magnetic resonance imaging (fMRI) makes the final diagnosis.

Diagnosis and examination methods

Diagnostic methods in neurology are varied:

  • X-ray examinations
  • Cranial base CT (CCT)
  • CT angiography (head and neck)
  • Computed tomographic examination from the temporal bone
  • Virtual otoscopy (endoscopy of the middle ear)
  • CT perfusion (strokes)
  • Magnetic resonance imaging studies
  • Diffusion imaging (determination of molecular motion of water molecules).
  • Functional magnetic resonance imaging (measurement of changes in tissue perfusion of brain regions).
  • Perfusion imaging (quantification and visualization of blood flow to tissues and organs).
  • Magnetic resonance spectroscopy (measurement of tissue composition).
  • Diffusion tensor imaging (measurement of diffusion movement of water molecules in body tissues).
  • Tractography (non-invasive examination method of the brain),
  • Angiography
  • Sonography (ultrasound examination)
  • Myelography (radiological contrast imaging of the spinal canal and spine).
  • Pneumoencephalography (imaging of the cerebrospinal fluid spaces of the brain).

During the examination by these imaging techniques, the patient can be treated in parallel, when a catheter is inserted into the brain to close ruptured vessels (aneurysms) or open occluded blood vessels. Needles can also be used to inject drugs into the area to be treated (e.g., the spine). In addition to these classic diagnostic options, interventional measures are possible to eliminate pathological conditions: widening of vascular stenoses, recanalization of vascular occlusions (thromboses), closure of vascular malformations (aneurysms). A patient is sent to a neuroradiologist whenever it is important to understand what is happening in the brain. Has the patient suffered a bleed in the brain or a stroke, or is Parkinson’s disease, MS or a brain tumor suspected? The neuroradiologist uses imaging techniques to find out which disease is present. Patients are also taken to neuroradiology in acute injury cases, for example after an accident, to find out whether there is a circulatory disorder and what its nature is. Neuroradiology still uses X-ray diagnosis, but it has receded in favor of modern diagnostic techniques because it cannot visualize the brain itself. However, imaging of the skull bones is very accurate, so this method of examination is often used for accident patients with suspected skull base fractures. Angiography is standard for the examination of brain hemorrhages in the form of vascular bulges (aneurysm). It is also based on X-rays, in which a contrast medium is used to mark the vessels in order to produce an X-ray image on this basis. Computed tomography (CT) detects both the bones of the brain and what is happening inside, such as bleeding. The patient is put through an X-ray tube. This produces cross-sectional or slice images. CT angiography can also be used to visualize the arteries responsible for blood flow to the brain after a contrast agent is administered. However, CT reaches its limits in visualizing minimal changes or injuries, in which case an MRI is induced. Magnetic resonance imaging (MRI) visualizes the brain in the form of density differences inside brain tissue at a high visual resolution using iodine-containing contrast agents. Hydrogen atoms are excited by the use of a powerful magnet and align in an external magnetic field, with the atomic nuclei emitting the signals necessary for the examination and allowing cross-sectional images to be made. Functional magnetic resonance imaging (fMRI) illustrates how the brain works and reveals increased blood flow. Brain functions are measured indirectly by blood flow. Nerve cells require energy to function properly. The brain is the organ that consumes the most energy. Positron emission tomography produces cross-sectional images just like MRI. The difference, however, is that artificial tracers are injected to visualize the brain’s metabolic process. The physician first clarifies whether the patient has a history of allergic reactions to contrast media, individual components or tracers. Some diabetes medications such as Juformin, Siofor, Glucophage or Diabesin form a contraindication to the contrast media. In the case of renal insufficiency, contrast agent-based imaging techniques must not be used because they are excreted by the kidneys. If the patient regularly takes medication, he must not discontinue it on his own responsibility before the examination, but must consult his family doctor. Tracers are radioactively mixed, exogenous (artificial) or endogenous substances that are used for the treatment or visualization of cancer cells.