X-RAY VISION: PROCEDURES HELP DOCTORS SEE INSIDE BODY

Jennifer Paper loaded X-ray film to make an abdominal X-ray of a patient.

Simsouda Mahathath, left, a radiology technician at Southeast Missouri Hosplital, positioned patient Stacy Cornell of Desoto for a chest X-ray.

Dr. Jesse Ramsey examined a child's foot X-rays for abnormalities.

In 1895, Wilhelm Roentgen, a German physicist, discovered a new form of electromagnetic energy, and changed medicine forever.

Roentgen's discovery, the X-ray, gave physicians their first non-invasive look inside the body to diagnose bone fractures, tumors, pneumonia and other ailments.

More than 100 years later, the CT scan, ultrasound and MRI procedures have been added to the diagnostic arsenal, but the X-ray, the grand daddy of all radiological procedures, is still leading the way.

In 1997, Southeast Missouri Hospital performed 46,709 diagnostic X-rays out of more than 74,000 radiological procedures, according to Tom Welch, who runs the hospital's radiology department.

Ernie Adams, radiology director at St. Francis Medical Center, says his hospital averages "in the neighborhood" of 52,000 diagnostic X-rays a year.

At both hospitals, most of the X-rays were ordered through the emergency room.

"We do them quite a bit, especially on patients coming through the emergency room," Adams said. "There's still quite a bit of need for the diagnostic X-ray."

X-rays are a form of electromagnetic energy, like visible light and radio waves.

But X-rays can penetrate substances that light can't, especially living tissues.

The images from diagnostic X-rays are called radiographs. The X-rays darken areas of sensitized film.

X-rays pass through softer tissues -- muscles and organs -- and expose, or darken the film. Dense tissues, like bone, absorb more radiation, and show up as white, or unexposed areas, on the film.

Air spaces let the most radiation through, and show up the darkest on film, so breaks in bone show up very well on radiographs.

Another common application for X-rays are fluoroscopes, which use substances that fluoresce, or glow, when struck by X-rays. Patients are given a contrast medium, such as barium sulfate, so the area being X-rayed shows up clearly.

Another outgrowth of the traditional X-ray is the CT, or computerized tomography, scan, in which X-ray emitters and detectors are mounted on a rotating ring to give a three-dimensional, "slice" view of the area being scanned.

Diagnostic X-rays "are utilized for more common things," said Welch. "If patients see a doctor and they've got a chest complaint and maybe a fever, the chest X-ray is the beginning point."

"You couldn't get by without the X-ray," Welch said. "The physicians would be lost."

Adams said the X-ray is "the first line of defense for ruling out fractures and very acute things, and then after that, you follow up with more sophisticated methods," such as the CT, MRI or ultrasound. "You can rule out a lot of things, congestive heart failure, pneumonia, spinal fractures, the lower extremity fractures."