By Polly Keary, Editor
For those fortunate enough to have limited experience with radiology, the differences between the various procedures and technologies can be pretty confusing. What, for example is the difference between an MRI and a CT scan? Where can you get them? How long do they take? What do they do?
Here is a guide to the technology and services available at Valley General Hospital in Monroe.
Digital Flouroscopy Unit-This large, imposing piece of technology allows doctors to, rather than simply take an X-ray for later examination, watch an image of the interior of the body as it engages in a process such as swallowing, digesting, or moving things through the intestines.
This allows doctors to look for things like tumors in the esophagus, ulcers in the stomach, or cancerous masses in the intestines.
CT Scan-The CT scanning machine at Valley General looks like a cot with a massive donut for a headboard. People under examination pass through the “donut hole” as the scan works.
“It’s quick, it’s fast, and you get an image in seconds,” said Douglas Clevenger, diagnostic imaging manager at VGH.
That makes the CT scan very useful in examining patients in the wake of a trauma such as a car crash in which quick action is often required. And when trauma is more complex or critical than Valley General can address, it helps doctors recognize that and send the patient on to Harborview.
“The CT scan is also very good at diagnosing renal failure, lacerated spleens, liver issues, masses in the pelvis that might be suspicious,” said Clevenger.
Ultrasounds-Unlike X-rays, an ultrasound doesn’t use radiation to capture images.
“It works like a radar beam,” said Clevenger. “You pass it over and you get an echo back, and it analyzes the echo and puts it on a monitor.”
Ultrasounds are most commonly used to monitor babies in-utero, he said.
Cardiac echo-A technology that works on much the same principal as ultrasound, but is specific to the heart, is the cardiac echo.
“It’s for following heart anomalies,” said Celvenger. “They are sort of a benchmark for things like adult heart murmur, valve disorders, the carotid artery. And doctors can listen and detect what they call a sound defect. They can pass the transducer over and tell whether the artery is narrowed or not.”
Digital mammogram-After the age of 40, women are advised to get annual mammograms to screen for breast cancer, and this is the machine that performs those scans. The breast is pressed between transparent plates and the machine takes pictures that can detect the presence of tumors while they are very small and much easier to treat.
What many women don’t know is that mammograms are very affordably priced, even for the uninsured, said Clevenger.
MRI-An MRI, or Magnetic Resonance Imaging machine, looks quite a bit like a CT scanner, but the donut is more of a tube than an hole.
It exerts a powerful magnetic pull on the body, which affects the water molecules that comprise much of the body. When the pull is released, the molecules return to their previous orientation, and that movement creates a frequency detectable by the machine, allowing for the creation of an image of internal structures.
The strength of the magnets used in MRI machines is measured in units called teslas. Most MRIs have strengths ranging from .2 to 3 teslas; Valley General’s MRI is a 1.5 tesla machine, which Clevenger calls state-of-the-art.
It is used to diagnose injury to the soft tissue of the body, such as cartilage in knees, shoulders, ankles and other joints. It is also used to look for causal factors in chronic back pain.
And it can be useful in scanning for cancers of the soft tissues, such as the brain, pelvis, or spine.
DEXA Bone Density scan-As we age, bones lose calcium and density and become brittle, increasing risk of fracture.
A DEXA, or dual energy X-Ray absorptiometry bone density scan, can measure the integrity of the bones.
The National Osteoporosis Foundation recommends that adults 65 and over, especially women, get a bone density scan, which is a painless test that requires about 15-20 minutes of lying on a table while the scanner works. The average cost nationwide for such a scan is about $150, making the procedure reasonable even for the uninsured.
The test can identify people who are good candidates for calcium therapy to rebuild bone density.
X-Ray-Aside from the familiar X-ray machine at VGH, there are also mobile units mounted on wheels that can be moved to the emergency department or to patient rooms, as needed. The hospital also has a standing X-ray. X-Rays aren’t as instant as are other forms of imaging technology, but results are typically available in a couple of hours, said Clevenger.
PACS: In a darkened room at VGH, a doctor sits before a screen, looking at X-rays. They could be from Valley General, but they could also be from any other hospital.
“PACS stands for picture archive and communication system,” said Clevenger. “It’s how we communicate. The radiologist reads films from a remote site, looks at the images and communicates the information to a doctor, and the information is stored digitally. Any top-notch radiology unit uses PACS.”