Neuropsychology is the specialized branch of psychology responsible for studying the functioning of the brain and its relationship to human behavior, that is, it seeks correlations between brain function and behavior, for this purpose uses different methods, such as computed axial tomography, better known by the acronym CT and magnetic resonance imaging (MRI).
These are two of the most widely used neuroimaging tests today, for the results they provide and for their accessibility and ease of use, but do we really know what their similarities and differences are?Here’s what we’re explaining next!
- CT scans and magnetic resonance imaging (MRI) are used to accurately locate.
- Quantify.
- And describe body structures that have been affected by an injury.
- And can also quantify lesions shortly after the occurrence and know the volume of tissue involved.
One of its strengths is its spatial resolution, excellent from a macroscopic point of view (1 mm TAC and 0. 5 mm MRI). In microscopic terms, the resolution is more modest.
On the other hand, and although not in all cases, to perform a CT or axial MRI it is recommended to fast 4 or 6 hours before, in addition, if the person has claustrophobia or tends to feel overwhelmed in closed areas, it is recommended that the patient consult his doctor to look for solutions, such as the application of anesthesia.
Computed Axial Tomography (CAT)
CT was the first neuroimaging technique available on the market since it was released in 1972, a date that marked a before and after in neuropsychology, since until then almost only post-mortem techniques were available.
CT is a type of tube-shaped scanner that can rotate between 180 and 360 degrees around the area you want to examine, the device emits x-rays simultaneously and from different angles, its purpose is to detect the parts of the body that absorb them. X-rays abnormally.
These detectors are sensitive to 1% variations in soft tissue density (compared to 10-15% of conventional X-rays). After this emission and captures the density variations, a computer collects the result in a series of images, these are axial and perpendicular to the cephalocaudal axis (from head to toe). Hypodenses appear dark (e. g. cerebrospinal fluid and fat), while hyperdes, such as bones or bleeding, have a lighter tone.
Unlike light, X-rays enter the body, this is a great advantage when observing the internal structures of the organization, so axial tomography is a very useful technique for detecting tumors, edema or strokes, and for bone and internal location. injuries, bowel diseases such as diverticulitis and appendicitis, or to visualize liver, spleen, pancreas and kidneys.
In turn, MRI is the technique that allows a greater contrast between soft tissues, that is, those that are not composed of bones, such as muscles, ligaments, meniscuses, tendons . . . Its discovery in 1946 greatly improved anatomical visualization, especially the difference between gray and white matter in the brain.
One of the biggest differences between CT and MRI is that it is very sensitive to fluid movement, allowing angiography (blood vessel images) without the use of contrast products; HOWever, CT is faster, but has a worse spatial impact. resolution than MRI.
Unlike CT, MRI allows images to be obtained on the three planes of space (horizontal, coronary, and sagittal), which in turn allows the use of a stereotactic atlas, for which these 3 spatial coordinates are required. it is possible to identify damaged structures that are not obvious to the naked eye.
MRI, as the name suggests, works with a magnetic field and radiofrequency waves, so unlike THE CT, which emits x-rays, the MRI does not emit radiation, however, MRI can be uncomfortable for the patient. Due to the unpleasant noise coming from the machine and the need to remain still during the exam.
MRI, like CT scans, cannot be performed if the patient has a metal object in the body because it can interfere with the test; is counteradadized in patients with cochlear implants (ear), heart valves, vascular clips, pacemakers or biostimulators.
MRI also does not produce iatrogenesis, i. e. it does not harm the patient’s health, as can occur during an operation in which the surgeon has to make an opening.
As you can see, there is no better revision than the other, but more or less appropriate depending on the purpose and type of structure to be examined. CT and MRI are two noninvasive methods that demonstrate the great advances in medicine. Advances that have implications for discoveries made in other fields, such as psychology.