WINSTON-SALEM, N.C. - To understand more about back pain, researchers are using sonography to study healthy people who are pain-free.
Dr. Francis Walker, professor of neurology at the Bowman Gray School of Medicine, explained in an interview that imaging healthy people may help define sonographic abnormalities. He will present his findings on August 16 at International Neurosonology ?97 conference sponsored by the World Federation of Neurology and the Bowman Gray School of Medicine of Wake Forest University.
Walker and three other Bowman Gray researchers independently analyzed sonograms of one cadaver and 39 healthy subjects. The goal was to define normal spinal and paraspinal anatomy.
Through independent analysis, each researcher found that sonography revealed the major landmarks of the spine and anatomy near the spine. At each of 23 levels of vertebrae imaged, all researchers recognized the spinous process (a sharp projection on vertebrae where muscle attaches to bone), the transverse processes (projections that flank the spinous process), facet joints, and musculature around the transverse process.
In the neck, sonography revealed nerve-root exits and other muscle as well as the spinous process, he said.
Occasionally, in very flexible subjects, sonography was able to reveal the spinal canal.
However, sonography was less effective farther down the back. In the lumbar region of the back (between the lowest ribs and the pelvis), the nerve roots and spinal canal were difficult to identify, Walker said.
Nonetheless, the Bowman Gray work lays the scientific foundation for interpreting sonography of normal backs and necks, giving added credibility to research already being conducted elsewhere that explores the use of sonography in patients with whiplash and other difficult-to-confirm diagnoses.
While admitting that sonography lacks ultimate resolution, Walker praised it as an interactive imaging technique that can be especially valuable in patients with back pain. Because sonographic scanners can be wheeled bedside and because the palm-size transducer that produces sonograms is guided freehand by a physician or technician, patients can direct the sonography ? straight to where it hurts.
"Patient input can precisely correlate sonography and a patient's symptoms," Dr. Walker said. Other imaging techniques like CT and MRI require large machines that must be programmed with an imaging protocol, deterring patient interaction.
With sonography, technicians are fewer; the machines, less imposing. And, as a corollary, sonography is less expensive than CT or MRI.
The next logical step, according to Walker, will be research that studies whether sonography can reveal what's wrong in patients with back pain.
For further information, call Mark Wright (email: mwright@bgsm.edu) or Bob Conn (email: rconn@bgsm.edu) at 910-716-4587.
Once the International Neurosonology '97 has begun on August 13, call the conference press room at 910-724-6923.