MRI or X-ray?

If the presence of a herniated disc is suspected, imaging procedures do not necessarily have to be used. Only in persons who suffer from pronounced symptoms, for example sensory disturbances such as numbness or tingling, a diagnosis should be confirmed by means of an imaging procedure. In this context, affected patients often ask themselves the question whether MRI, CT or X-rays are best suited to depict the individual spinal segments.

While magnetic resonance imaging (MRI) works completely without radiation exposure, CT or X-ray imaging involves considerable radiation doses acting on the patient under examination. In general, it can be assumed that the radiation exposure is many times higher when a CT is performed. In this context, however, it must be noted that several x-rays must usually be taken to visualize the spinal column.

In terms of radiation exposure, it is therefore almost irrelevant whether the diagnosis is made by means of CT or X-ray. Nevertheless, X-rays are considered unsuitable in the diagnosis of a herniated disc. The reason for this is the fact that only bony structures can be usefully imaged with X-rays. The nerve tissue as well as the intervertebral discs, however, can only be displayed with the help of an MRI or CT.

MRI or CT?

In principle, both magnetic resonance imaging and computed tomography are suitable for the diagnosis of a herniated disc. The question of whether an MRI or CT is the more suitable imaging method for an affected patient depends on various factors. Basically, it should be noted in this context that when a CT is performed, high radiation levels act on the patient under examination.

MRI, on the other hand, works completely without harmful radiation. For this reason, the choice of whether to perform an MRI or a CT should be based on the preparation of an MRI first. On the other hand, people who have a pacemaker or electromechanical implants (e.g. cochlear implants) cannot choose between MRI or CT.

In these cases, the sectional images of the spine must necessarily be taken using a CT. In addition, when choosing between MRI or CT, it must be borne in mind that in patients who suffer from very severe back pain and pronounced irritation of the sciatic nerve, computer tomography (CT) can provide a more precise indication of the cause of pain. A herniated disc can be reliably diagnosed as such both in the MRI and in the sectional images of the CT.

Can you miss a herniated disc in an MRI?

The MRT examination (abbreviation for magnetic resonance imaging) is a so-called slice imaging. The body region to be examined is imaged layer by layer. Typically, this produces images which are taken at a distance of a few millimetres from each other.

Thus, theoretically, a quite accurate three-dimensional image reconstruction of the examined body region is possible. Due to its physical background, the MRI is particularly well suited for displaying structures such as bones, ligaments and tendons. For this reason, an MRI is preferred in the case of a slipped disc.

Most herniated disks are detected on the images. But even a particularly small herniated disc can be hidden between the individual slice images and therefore be overlooked. In addition, there are often findings that do not cause any discomfort to the affected person. Therefore, the evaluation of the MRI images requires the expert eye of a radiologist.