Herzliya Medical Center
The various imaging examinations that today are considered to be standard, a service that is taken almost for granted, created a revolution in the world of medicine in their early days, for one simple reason: they enabled the assessment of the body’s internal parts and systems without performing any invasive procedure. Over the years, a host of different types of imaging examinations have been invented and developed. One of the most advanced today is the MRI scan – an examination that uses magnetic resonance, providing the physician with a clear and precise picture of the organ being examined. At Herzliya Medical Center Hospital, MRI scans are performed at the advanced Imaging Institute, which is equipped with some of the world’s most modern and advanced MRI machines.
As is the case for all current imaging examinations, an MRI scan is intended to enable the diagnosis of systems or organs located within the body, that the human eye cannot assess. The examination is performed using magnetic resonance, hence its name – Magnetic Resonance Imaging. It creates, using the radio waves emitted by the machine, a detailed three-dimensional image of the area that the physician asked to examine.
A very high-quality image is obtained, which can even be ‘sliced’ up into sections, in order to examine the area being assessed in more depth. The physician is thus presented with a full, precise and detailed picture, with which he can diagnose a range of medical problems and issues relating to the area being examined.
The central nervous system (the brain and the spine)
This is, of course, just a partial list. MRI scan can show the physician’s blood vessels, bones and the structure of the skeletal system, tumors (benign and malignant), metastases of cancerous tumors, lesions indicative of multiple sclerosis, various functional areas of the brain, and much more.
The actual examination is performed with the patient lying on a straight, long, and narrow bed (the size of a single bed). After lying down on the bed, the patient is moved on it into a particularly large tube, with a type of tunnel at its center. The bed, with the patient on it, slowly enters the tunnel, in which the magnet is located, which produces the resonance needed to create the image.
The bed will be stopped by the technician who is operating the machine so that the organ to be examined is lined up with the magnet. When the bed reaches the required location, the machine will begin to work, which could be quite noisy.
In order to reduce the discomfort, the patient will usually receive earplugs before the examination, which will significantly reduce the noise. Sometimes, contrast material will also be injected to his body; this can help the physician assess various areas of the body. This material is gadolinium, which is considered to be relatively ‘tolerable’ for the body (as opposed to iodine used in CT, which can sometimes cause allergic reactions).
An MRI scan usually takes some 40 to 45 minutes, and it is very important to avoid substantial movement during the examination. Therefore, when an MRI scan is being performed on children or on adults who are unable to comply with this requirement, the option of deep sedation or even anesthesia will sometimes be considered. If the physician wishes to utilize the scan to assess several organs or areas together, the examination could even take more than an hour – therefore, in such instances, you will sometimes be given appointments for several examinations instead of one long examination.
Prior to the examination, it is important to remove all jewelry or accessories that are on your body and to inform the medical staff of the presence of implants (e.g. joints, heart pacemakers, intrauterine devices, etc.). People who work with metals are also required to inform us of this in advance, since sometimes tiny metal particles adhere to their skin, without their being aware of this, and these could be affected by the magnetic action that occurs during the examination – even to the extent of heating up and melting.
In addition to all this, you may on occasion be asked not to eat for an hour or so before the examination.
As mentioned above, the MRI scan is capable of assessing various bodily organs and many systems, but it is not suitable for every situation. For example, an examination of the lungs is not suitable in this case, as MRI technology is not capable of reflecting their condition.
You will usually be referred for a magnetic resonance scan in three main cases:
These two latter points hint at one of the big advantages of MRI scans: these scans do not emit radiation, as opposed to x-rays and CT scans. MRI scans are therefore considered safer and healthier for vulnerable populations such as small children and pregnant women.
It should be noted that MRI scan in many instances also provides a picture in more depth and detail than all the other imaging examinations, but as we have indicated, it is not suitable for examining all bodily organs, so there is a need to judge when it should be used.