Molecular Imaging Insight - May 2008 - (Page 15) says Larsson. The technology has shown to be particularly helpful in lung cancer and liver transplant cases. Take for example a surgical lung cancer case. If the tumor has metastasized outside of the lungs, the patient is seldom a surgical candidate. Conventional imaging, however, does not provide a clear guidance. “Biograph with TrueV is much more accurate,” Larsson says. “Surgeons are more sure of what they see, and whether or not the tumor has metastasized beyond the lungs. They are better able to determine appropriate treatment, which means better patient outcomes.” In addition to providing improved clinical images, the system offers new levels of efficiency. For example, a conventional 2D axial PET whole-body scan with a 10 cm field of view can take an hour or longer. A three-detector ring PET/CT scanner reduces the scan time to 15 to 20 minutes. Biograph True V delivers additional improvements by cutting scan time to 10 to 15 minutes. Karolinksa University Hospital/Institute is capitalizing on the reductions in scan time by increasing patient throughput. “When we first started PET/CT scanning in May 2006, we scheduled four to five patients a day on the three ring, 16 cm field-of-view system. When we upgraded to the fourth ring, we increased the patient load to 10 to 12 patients daily,” explains Larsson. The hospital aims to increase throughput again by beginning FDG injections at 8:30 am rather than 10 am. “We’ll easily be able to run 15 to 16 patients each day.” In addition, the shorter scan time delivers additional image-quality benefits, says Larsson, as patients are much less likely to move during a 15-minute scan than they are during a one-hour study. The faster throughput benefits both patients and the bottom line, says Larsson. Patients have shorter wait times, which can accelerate the care cycle. And Karolinska increases its revenue via the additional patient load. Another plus associated with Siemens Biograph PET/CT is the solid engineering behind the scanner. “Usually new systems have bugs in the software and higher than normal downtime,” Larsson says, “but we’ve had very few problems with this solution.” The lack of downtime has allowed the site to build momentum in PET/CT imaging as radiologists and technologists build their skills and exploit the capabilities of the system. Biograph PET•CT system “A conventional PET scanner includes three detector rings, which create an axial field of view of approximately 16 cm. Biograph with TrueV adds a fourth detector ring, which increases the axial length to 21.5 cm. It is quite an improvement.” Stig A. Larsson, PhD, head of department of nuclear medicine, Karolinska University Hospital/Institute in Stockholm, Sweden medicine experience. The solution, however, was fairly simple. Karolinska sent the new techs to two training courses to bring them up to speed with PET/CT technology. Future directions Karolinska University Hospital/Institute remains in the early stages of PET/CT scanning and anticipates additional gains as physicians better understand the capabilities of the Biograph with TrueV. One area of intense interest is gated respiratory and cardiac studies. Larsson and his colleagues are investigating the utility of the system in gated exams. “It is reasonable to predict that the scans will be quite useful,” notes Larsson. Once again, he credits the extended-field-of-view capabilities for the improvement. “The technologist can extend the field as the lung tumor moves, so that the field always covers the tumor.” The improved coverage, in turn, helps radiation oncologists better define the target and confine treatment to the tumor. Larsson foresees PET/CT opening other doors as well. For example, the combination of 64-slice CT with the increased sensitivity enabled by the larger field of view is expected to improve results in cardiac studies — for instance by dynamic studies using 11C-acetate. Another option is dynamic studies of the lungs and liver. PET/CT could be used in place of SPECT to determine energy metabolism and other biochemical mechanisms in various organs. A very interesting approach would be to test a variety of some specific substances for tumor imaging to evaluate the pathological nature of the tumor tissue. May 2008 | Molecular Imaging Insight 15 Setting the stage for optimal deployment PET/CT does bring significant results and benefits; however, it requires some adjustments, particularly in the area of staffing. “It’s important to realize that PET/CT takes some time to interpret,” notes Larsson. Karolinska Institute/ Hospital ensured high-quality, timely turn-around by adding a second nuclear medicine physician to its staff, and Larsson expects to hire a third specialist in the next year. Staffing considerations extend beyond physicians. Karolinska also hired two new technologists to staff its PET/CT scanner. Larsson cautions, “It can be challenging to find techs experienced in both CT and nuclear medicine.” In fact, the hospital’s new techs both came from a CT environment and lacked nuclear MolecularImaging.net http://MolecularImaging.net
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.