Advantages of Magnetic Resonance Imaging
- no radiation exposure (compared with X-ray and computed tomography)
- According to current knowledge, the investigation has no lasting side effects
- Certain structures, in particular soft tissue such as nerves or brain, can be better (or even for the first time)
- Tumors, inflammation and injuries are especially visible
Disadvantages of MRI
- Costs: A major disadvantage is the cost of both the purchase and during operation.
- Artifacts and Resolution: Compared to the CT image, artefacts occur more often, technical structures that overlay the actual image and can lead to misjudgments. The resolution of the images is limited to about one millimeter.
- Metal: A disadvantage is also that metal on or in the body (for example, coins, keychain, metal splinters, vascular clips, intrauterine device) cause image disturbances or may heat up or relocate, so may be dangerous for the patient. However, the implants used today, such as artificial hip joints, are no longer a problem; Contraindications include cochlear implants, implanted insulin pumps and the first trimester of pregnancy. Even with large tattoos is not recommended by the MRI, since the color pigments contain metal. Carriers of a cardiac pacemaker have not previously been examined by MRI, but some major centers are now offering this.
- Tight tube: For many patients, the narrow tube is very uncomfortable with whole-body tomographs, which has an average diameter of 60 cm and is about 160 cm long. In individual cases, the examination is therefore performed with tranquilizers or even under anesthesia. With the smaller devices, with which also individual body parts can be examined, this is unnecessary.
- Risk of blurring and loudness: Silence is very important - a special challenge with the loud knocking sounds of the device. Hearing protection is therefore mandatory, in addition, a sleeping aid may be necessary especially in children.
- Allergy: In some questions or special examinations (for example, MR angiography = MRA), a contrast agent is given in addition, which in turn may cause allergic reactions in individual cases.
- Duration: And last but not least, the investigation - despite all developments - continues to take a relatively long time.
In order to expand the application areas and minimize the disadvantages, the research is far from complete. They range from more powerful magnetic fields, to more sensitive sensors, to the measurement of other atomic nuclei, to make specific structures such as cancerous tumors more visible.
The development of MRI procedures not only for diagnostics, but also for cause research, surgical preparation and therapy control are progressing steadily. Thus, metabolic processes such as brain activity can be measured (functional MRI = fMRI) - now even in real time.
Importance for brain research
A great potential to gain new insights, especially in the current areas of brain research and neuropsychiatry, for example in diseases such as schizophrenia.
And even for other areas, such insights into our inner worlds may be interesting - for example, the advertising industry hopes to be able to predict when which brain regions will react as if they were advertising.