Aug. 14, 2006
By Christina Dierkes
The image of a mouse floats on the computer screen, slowly turning to reveal all sides of the critter. Body fat, marked in bright red, grows on the mouse's belly, showing researchers where this health-damaging fat tends to accumulate. Next to the mouse, an image of an alligator embryo in fluorescent green, undamaged and still in its eggshell, slowly rotates in sync with the mouse as its skeleton is revealed. Those images are only the beginning of what's possible with Ohio University's newest piece of research technology.
Ohio University's Research Priorities Program has brought several new pieces of research equipment to campus, and the latest addition provides researchers with the capability to create highly detailed X-ray images of very small objects.
As part of the Nanobiotechnology Initiative, the university purchased a $250,000 MicroCT machine, which is now housed in the Konneker Research Center. The machine, which is essentially a smaller version of a hospital's CT scan machine, uses X-rays to create images of objects up to the size of a grapefruit, said Larry Witmer, professor of anatomy in the College of Osteopathic Medicine.
"The machine lets us answer questions that we never could before here at Ohio University," Witmer said. "It changes the kinds of research we can do."
The MicroCT works at a higher resolution than regular CT machines, Witmer explained. CTs create visual slices of humans or other scanned objects, with the slices between one and five millimeters thick.
"If the subject is measured in millimeters or centimeters, that resolution is too big," Witmer said. The MicroCT works at the micron level, and its smallest resolution is 27 microns, or 0.027 millimeters. By comparison, a sheet of copy paper is about 0.1 millimeter thick and human hair averages at 60 to 80 microns.
Another advantage of using a MicroCT to create images, of lab animals for example, is that the study subjects do not have to be euthanized to collect data. For example, an obese mouse used to study the distribution of body fat can be anaesthetized and scanned to show where the fat is located in its body, without having to dissect it. "We can now do longitudinal studies on the same animal," and follow body fat or tumor development over a longer amount of time, said David Wight, director of the Edison Biotechnology Institute. The institute's main research focus is on diabetes and cancer treatments, but also includes other biomedical research problems.
Witmer's research on bone structure has already benefited from the MicroCT's capabilities. He is working on the creation of a Virtual Pig, which will allow researchers to use 3D images to study pig body parts that are closely related to the human body. One of these parts is the temporomandibular joint, or TMJ, the painful or stiff jaw joint that can cause problems for people who grind their teeth. The MicroCT allowed a closer look at this particular joint in a pig, but the resulting images can be applied to humans and used to find treatment options for TMJ problems.
A number of other researchers will also benefit from the purchase of the MicroCT, and many have proposed future research, which was "conceived in a sense as a result of us getting this piece of equipment," Witmer said. The topics range from diabetes, obesity and tumor growth, to engineering projects that examine the structure of building materials. Many of these projects also utilize other capacities of the newly created imaging suite in the Konneker Research Center, which is still expanding, but already contains luminescent and fluorescent imagers as well as an instrument which can be used to determine body fat ratio in live mice and rats – along with the MicroCT.
The Ohio University MicroCT panel, which organizes training sessions and access to the machine, includes Witmer, Research Technician Ryan Ridgely, Jundong Liu of the Russ College of Engineering and Technology, Darlene Berryman of the College of Health and Human Services, Kelly McCall of the Diabetes Research Center and Maria Lozykowski of the Edison Biotechnology Institute. The panel continuously reviews applications to use the MicroCT, and is organizing training sessions for researchers who want to use the machine over a period of time. Those who only need one-time access to the machine do not need to be certified, but have to contact a certified user to do the scans for them.
More information about the MicroCT is available on the Web at: http://www.oucom.ohiou.edu/ou-microct
Christina Dierkes is a graduate assistant in the Office of Research Communications.