Upright MRI
The role of cervical spinal instability in the genesis of spinal cord injury (cervical myelopathy) and the complete extent of
that instability over the full range of flexion and extension positions that a patient’s cervical spine occupies can now be measured
in the FONAR UPRIGHT® Multi-Position™ MRI. Additionally, the measurements can be performed in the FONAR
UPRIGHT® Multi-Position™ MRI with the patient in the UPRIGHT® position where the spine is supporting its full weight
load.
Magnetic Resonance Imaging
The extent to which disc degeneration and the occurrence of spondylolistheses are correlated and the full extent of the
spondylolistheses that occur when cervical flexion and extension occur in the UPRIGHT® body position was measured in 168
patients suffering from neck pain.
Upright MRI
To evaluate the degree to which cervical vertebral slippage was a candidate for inflicting cervical cord injury, UCLA scientists
measured the extent to which cervical vertebra slippage (spondylolisthesis) increased as a function of disc degeneration. The
extent to which slippage increases as a consequence of disc degeneration is the first step in evaluating the potential of a patient’s
spine pathology for causing cervical cord impingement, cervical cord injury and ultimately cervical myelopathy.
Muhle, et al.,4 for example, in a flexion-extension recumbent MRI study of patients with neck pain concluded that “cervical
spinal motion may contribute to the development of cervical spondylitic myelopathy.” Their conclusion was the result of
their data that showed “at flexion and extension, the prevalence of spinal stenosis and cervical cord impingement increased
as the stage of degenerative disease progressed.”
Additionally, Muhle, et al. described the possibility of a “PINCER CONDITION” arising with respect to the patient’s cervical
cord wherein cervical disc degeneration and the consequent loss of disc height results in spinal cord pinching from intervertebral
disc bulging anteriorly and cord pinching from infolding of the ligmentum flavum posteriorly.
The Muhle, et al. study is compelling regarding the prospect of serious injury to the spinal cord when the cervical spine
with degenerative pathology engages in its normal range of flexion and extension motion.
The Muhle, et al. study, however, necessarily underestimates the injury potential of such degenerative pathology since the
study was performed with the patients recumbent when the full extent of the compressive forces of weight loading were not
engaged.
The UCLA study using the FONAR UPRIGHT® Multi-Position™ MRI evaluated the potential for cervical instability to
induce cord injury with the patients fully UPRIGHT® with the cervical spine subjected to its normal compressive gravitational
forces of body weight.
The study established that cervical spine translational and rotational instabilities increase as disc degeneration increases
finally reaching an ankylosing stage where translational and rotational mobility is reduced relative to normal. In their paper
“Multilevel cervical spondylosis: laminoplasty versus anterior decompression” Hirabyashi and Bohlmon report that “cervical
spondylosis is the most common cause of cervical spinal cord dysfunction in individuals older then 55.”5
The full range of motion analysis of the cervical spine made possible by the FONAR UPRIGHT® Multi-position™ MRI
further enables the future implementation of clinical treatments that limit cervical motion to positions that do not encroach on
the cord and cause injury. The FONAR UPRIGHT® MRI also now makes possible post-operative image analysis to verify that
cord impinging and cord injuring conditions have been successfully eliminated by surgery.
The study by UCLA of patients with neck pain was the first demonstration in the fully UPRIGHT® patient of the degree to
which the cervical spinal cord can be exposed to injury from spondylolithesis secondary to cervical disc degeneration. The
study proved that potential cord injuring cervical spine instability increased as a function of cervical disc degeneration, consistent
with the conclusion of Muhle, et al. that cervical spinal motion may be a contributor to the development of cervical
spondylitic myelopathy. The FONAR UPRIGHT® Multi-Position™ MRI technology was shown to be capable of quantifying
existing spondylolistheses and assessing the cord injuring potential of degenerative spine changes that exist in the neck pain
patient so the prospect of myelopathy can be assessed and surgical (or non-surgical) treatments implemented to prevent injury.
“POSITIONAL MRI: A VALUABLE TOOL IN THE ASSESSMENT
OF CERVICAL DISC BULGE” (PAPER 80)
UCLA scientists further assessed another major component of cervical spondylosis, namely the cervical disc degenerative
pathology manifest as disc bulges and the variation of these bulges with flexion and extension, when the criterion for designating
a disc prolapse as a bulge was a visible bulge 2 mm or greater.
The UCLA studies concluded that 25.08% of the time there was a failure to see disc bulges in the neutral sitting position
that became evident when these 163 patients with radicular signs and symptoms were additionally imaged in the flexion and
extension positions. 18.18% exhibited a bulge 2 mm or greater in flexion that was less than 2 mm in the neutral sit position and
23.75% exhibited a bulge 2 mm or greater on extension that was less than 2 mm in the neutral sit position (Table 2).
Additionally, in the UCLA study of patients with low back pain, “The Effect of Lumbar Flexion and Extension on the
Central Canal with Dynamic MRI” (Paper 79), Wei, et al. assessed the capability of the FONAR UPRIGHT® Multi-
Position™ MRI to quantify spinal stenosis, the most common reason for spinal surgery in patients older than 65 (Katz, J.,
et al., Rheum Dis Clin North Am 1994:20:471). In their study of 461 patients with low back pain, UCLA scientists reported
that they were able to measure spinal canal diameter in the vertical patient and quantify its changes with flexion and extension
“with high precision” using the FONAR UPRIGHT® MRI. They further reported the ability to measure the flexion and extension
changes in the spinal canal cross-sectional area “with the highest accuracy.”
Lumbar spinal canal stenosis and the entrapment of the cauda equina roots, which is a consequence of the constriction of
spinal canal dimensions produced by stenosis, results in the symptom complex intermittent neurogenic claudication – manifest
as debilitating pain in the back and lower extremities, weakness and difficulties in ambulation, and leg paresthesias. The
ability of the FONAR UPRIGHT® Multi-Position™ MRI to quantify key spinal canal dimensions with “high precision” in all
the UPRIGHT® body positions brings to the highly skilled and specialized craft of spine surgery a new and much needed technology
for quantifying the full extent of spinal stenosis in patients.
Additionally, the power of FONAR’s new UPRIGHT® Multi-Position™ MRI to measure spinal canal dimensions with the
body in its UPRIGHT® position and the spine fully weight-loaded, with the gravitational compressive forces responsible for
back pain fully engaged, means that FONAR’s new technology is now available to surgeons to quantify the full extent of
stenosis responsible for claudication symptoms in their patients and to do so with their patients fully UPRIGHT® and
occupying the full range of body positions they do normally.
It is self-evident that measurements of canal stenosis made in a conventional MRI with the patient lying down are an underestimate
of the full extent of the stenosis that exists when the patient is UPRIGHT® with his spine subject to the full extent of
gravitational forces that normally compress the spine.
Indeed, when conventional recumbent MRI scans do not visualize pathology that corresponds in severity with the intensity
of claudication symptoms, the likelihood is that recumbent MRI is not seeing the full extent of the stenosis the patient is experiencing
UPRIGHT® with his/her spine subjected to its full weight-load and occupying its normal flexion and extension positions.
Potential for Greater Precision in Optimizing Decompression
Moreover, current procedures for decompressing spinal stenosis can, from the surgeon’s perspective, be limited by the
expected impact of the procedure on spinal stability. It is likely that a full quantitative multi-position assessment of central
canal stenosis measured simultaneously with quantitative multi-position analysis of spinal stability – a combination that is
now possible using FONAR’s new UPRIGHT® Multi-Position™ MRI technology – will enable surgeons to achieve greater precision
in optimizing decompression while at the same time minimizing spinal instability.
IMPROVED SURGICAL OUTCOMES
DYNAMIC DIAGNOSIS OF THE SPINE TOTALLY WEIGHT-LOADED, UPRIGHT AND OCCUPYING ITS FULL
RANGE OF NORMAL PHYSIOLOGICAL POSITIONS MEANS A MORE ACCURATE DIAGNOSIS, IMPROVED
SURGICAL OUTCOMES AND, AS A RESULT, INCREASED PATIENT REFERRALS.

1 Comment »

1. Stephon Bender Said,

   November 12, 2008 @ 8:51 pm

   9f0swltwc767z8e7

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