Feature: MSU Radiology Lab Boasts Nation's Best
With a new state-of-the-art cyclotron and scanner, MSU Radiology now boasts the most advanced fusion technology in the nation.
If you are lucky, you will never have to enter the new radiology laboratory on campus nor see the recently-acquired, state-of-the-art cyclotron and PET/CT (Positron Emission Tomography and Computed Tomography) scanner.
Once the systems started operating, only authorized persons and patients have been allowed to enter. But if you should develop a serious medical problem that you, your physician, and insurance company believe could best be diagnosed by the new scanner, you will enter the building knowing that you are fortunate to have access to the best scanner in the land.
Before the systems started operating, though, Thomas Cooper, assistant chairperson of the Dept. of Radiology, was able to provide a tour of the new facility, beginning in the basement. He led the visitor down a zigzag hallway, through three-inch thick lead doors, into a part of the building surrounded by massive reinforced concrete walls. It became quite clear that no cost-cutting shortcuts were employed in constructing the building. It was built by a company with years of experience designing similar facilities. The construction manager had personally overseen the building of nine other cyclotron facilities. The campus radiation safety officer made sure that the structure conformed to the highest safety standards.
Surrounded by all these safeguards, the new cyclotron sits in a room by itself. Unlike other cyclotrons, this one performs only one function—produce radioactive ingredients necessary for positron emission tomography (PET) scanning. It is not designed to facilitate the understanding of subatomic particle interactions as is the National Superconducting Cyclotron Laboratory, also located on campus. After pointing out the purpose of the huge magnets and sophisticated valves and tubes of the cyclotron, Cooper explained how the cyclotron accelerates charged particles and converts a special form of oxygen into an unstable (radioactive) form of flourine. The now unstable (hot) isotope is transferred upstairs through the connected system of tubing into a biosynthesis unit where it is mixed with glucose to become FDG (fluorodeoxyglucose) and eventually injected into a patient who is to be scanned.
MSU has formed a partnership with Cardinal Health Company to prepare and distribute statewide the radioactive pharmaceutical (radiopharmaceutical) FDG produced in this facility. Because this material is radioactive and decays fairly rapidly (half-life of about 120 minutes), there is a limited time within which the compound must be used. The half-life is the time required for half of the radioactivity of a substance to go away. The facility can manufacture radiopharmaceuticals with half-lives ranging from two minutes to two hours. The time limits mean that well before daybreak, technicians start the manufacturing process to generate the required dosages for the day. Because of the short life of the pharmaceutical, its market will be limited to regional areas. MSU has already made agreements to provide FDG to other medical imaging facilities across the lower peninsula.
A patient who is to be scanned will enter the building and be escorted to a room with lead walls and door. Then the previously prepared radiopharmaceutical FDG will be carefully transported in a very heavy tungsten container along a lead-walled hallway to the room for the waiting patient. After the patient is injected, he or she sits in a reclining chair for about 60 minutes. The next move is into the room where the new scanner awaits.
Kevin Berger, director of PET/CT, explains the advantages and uses of their sophisticated equipment, particularly in oncology. Most cancers, he notes, including lung, colorectal, breast, lymphoma, head and neck, and melanoma, are more metabolically active than normal tissue and use more glucose. The radioactive form of glucose (FDG) becomes trapped and more concentrated in the tumor cells. The FDG emits a high energy particle called a positron. The positron meets an electron within the body, and a reaction occurs which produces two high energy photons which are detected by the PET scanner. As the metabolic changes in abnormal cancer cells typically precede the anatomic changes, PET scanners are more sensitive to detecting tumors than conventional anatomic imaging devices such as MRI or CT. However, anatomic imaging devices such as CT provide very high resolution images of the body that allow more precise localization.
“By combining the PET and CT scans in a single patient exam, we simultaneously realize the benefits of the high sensitivity of the PET scan and the precise anatomic localization of the CT scan,” says Berger. “Fusion PET/CT scanning improves the accuracy of diagnosis and staging of many common cancers to the benefit of the community that we serve.”
He adds that MSU is proud to provide patients access to “the first world-wide, commercially operational, GE Discovery ST PET/CT scanner.”
MSU’s PET/CT system represents a significant advance in oncology care because it increases the accuracy of diagnosis and staging of a patient’s disease. The advances in combined PET/CT scanner technology has approximately halved the amount of time to create a PET image while simultaneously improving the sensitivity of the scan. Patients appreciate the shorter, more comfortable scan times while enjoying the view from a skylight installed above the PET/CT scanner.
Initially, MSU Radiology expects to scan only two to three patients per day. Eventually, this number will increase to six or eight. MSU is also working to bring the benefits of PET/CT to the detection of heart disease where combined images of cardiac perfusion from PET and coronary anatomy from CT will advance how doctors can noninvasively study their patients.
What becomes of the radioactive pharmaceutical after the scanner has done its work? The isotope decays and leaves the patient free of contamination.
The new PET/CT scanner is an addition to the already existing imaging capabilities at MSU. The well-respected MRI facility has been in operation for several years and has done thousands of MRI body scans. MSU owns two scanners located in the campus lab and three more off campus in a joint partnership with Sparrow Hospital.
MSU will continue to keep pace with the most recent developments in nuclear medicine. E. James Potchen, radiology chairperson and University Distinguished Professor of Radiology, explains that the major focus has now shifted to molecular imaging which allows radiologists to utilize PET and other imaging technologies to scan for other phenomena. For example, he foresees exciting breakthroughs in the mapping of genomes to provide information about why individuals react differently to medications. He points out that medications are now predicated on statistical averages of what patients need or can tolerate. Such a formula does not allow for exceptions. The potential for providing individualized medication is but one possibile use for genome mapping.
“We are committed to staying at the forefront of this and other new developments in the field,” says Potchen. “PET imaging and cyclotron-produced radioisotopes provide a unique venue to visualize biological function in human beings. This new facility uniquely poises the university to study the complex relationship between the human environment and the development of disease.”
Macel D. Ezell is MSU professor emeritus of American Thought and Language, and occasional free-lance writer.