OF NORTH AMERICA 2003 (RSNA): Scientific
Neuroradiology/Head and Neck (My Aching Back)
THE POTENTIAL VALUE FOR MRI IMAGING IN THE
SEATED POSITION: A STUDY OF 63 PATIENTS
SUFFERING FROM LOW BACK PAIN AND SCIATICA.
DATE: Thursday: December 04, 2004
START TIME: 11:00 AM
END TIME: 11:07 AM
LOCATION: ROOM N228
Francis W. Smith, MD
University of Aberbeen, Scotland, U.K.
CO-AUTHOR: Malcolm Pope, PhD.
Keywords: Spine, MR
With the availabilty of an MRI scanner capable of imaging in the
erect postion and also open enough to allow for images of the lumbar
spine to be obtained in flexion and extension, a study of 63 consequetive
patients suffering from low back pain and sciatica referred for
MRI examination was undertaken to assess what changes may be seen
in different positions.
METHODS AND MATERIALS
consecutive patients suffering from
low back pain and/or sciatica, that had been referred for
routine MRI examination, were studied. There were 20 female and
43 male patients aged 35 - 67 years of age (Mean 42 years). Each
was exmined in a 0.6T Indominitable Stand-up MRI scanner (FONAR,
Melville, New York). Sagital T1 and T2 images were made in the Supine
and seated position. In the seated position the spine was imaged
in neutral, flexed and extended. Transverse T2 weghted images were
also made in neutral and in flexion. Each examination was evaluated
by two trained observers.
In all of the cases there were at least one intervertebral
disc which showed a loss of signal from the nucleus on the T2 images.
There was no difference in disc height between supine and seated
in the healthy discs. In those showing loss of signal from their
nuclei there was a reduction in heightof between 1 - 3 mm. In 56
cases there was obvious prolapse of an intervertebral
disc, whose degree of prolapse changed between the neutral position
and either flexion or extension. In 6 cases there was anterior
movement of disc and superior vertebra, on forward flexion demonstrating
previously unsuspected spinal instability. In the other case an
unsuspected position dependant spondylolisthesis showing associated
tear of the interspinous ligament was found.
The ability of MRI images to be obtained in flexion and extension
enables a diagnosis of spinal instability to be made with confidence.
The alteration in disc height and appearance between the three positions
is of great interest and requires further detailed study in a larger
group of patients.