Weight Bearing and Positional imaging
Due to the unique nature of our scanners, we are able to perform weight bearing and positional imaging. The revolutionary design of Upright MRI scanners allow patients to simply walk in and be scanned in a sitting or standing position. The Upright MRI allows all parts of the body, particularly the spine and joints, to be imaged in the weight bearing state to show the effect of gravity on the spine. This can be particularly useful with sports, injuries as we can place the patient into the position where they have the most pain. We have already successfully diagnosed injuries in, for instance, footballers, rowers, cyclists and gymnasts. The system can also rotate the vertically-oriented patient into a horizontal position so the patient can be scanned in a supine position, as in conventional MRI scanning.
With our technology, we are able to:
- Scan patients in flexion, extension, rotation and lateral bending
- Scan patients in a sitting position
- Scan patients lying down
- Scan patients in their position of pain
- Scan patients whilst they are weight bearing
It should come as no surprise that the MR appearances of the spine are not necessarily the same in the upright as in the supine position, because of the weight-bearing state of the former. But of course, the key question is: does this method of scanning influence patient management?
In a paper presented to the European Society of Skeletal Radiology (ESSR) in July 2005, Smith and Siddiqui reported twenty-five patients referred for MRI of the lumbar spine for sciatica following at least one prior, “normal” MRI examination within six months of referral. 14 men and 12 women aged between 38 and 67 years of age were scanned using an upright MRI Scanner. Each patient was scanned supine, standing erect and in the seated position. In the seated position, images were made with the back in neutral, flexed and extended. Sagittal T2 and Axial T2 weighted sections were made through the lower five intervertebral discs in each position.
In twelve cases, no significant abnormality was seen in any of the five postures. In thirteen, abnormalities were demonstrated in one or more of the seated postures that were not evident in the conventional supine examination. In three cases lateral disc herniation was only seen in the seated position. In six cases the presence of a hypermobile disc at one or more levels was demonstrated. In two cases a previously unsuspected grade 1 spondylolisthesis was shown and in two cases significant spinal canal stenosis was seen in the seated extended position.
In 50% (13/25) of these cases that had previously been investigated for sciatica, a surgically remediable lesion was found. Each of the thirteen patients has undergone appropriate surgery and six months post surgery remained symptom free. We have been operating for over ten years now, and our experience is consistent with the Smith and Siddiqui study – we are routinely detecting findings which show the benefits of weight bearing imaging.