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- In nuclear medicine, 80 percent of all imaging uses technetium-99m
- There is no reliable domestic supply of Mo-99
- "The plan that everyone depended upon went away,"
- "The reactors in Canada and The Netherlands are 40 to 50 years old
- "The reactors are at the outer limits of their useful lives."
- Pressure
- A prolonged shutdown of one reactor
- The NRU shutdown was followed by the idling of the second largest reactor source, the High Flux Reactor
HEU – UqWorldwide shortage of medical isotopes coming now – causes doctors to delay treatments Ponto and Guiberteau 9 (James – M.S., B.N.C.P @ University of Iowa & Milton J – M.D. @ University of Texas Medical School, June 2009, http://www.rsna.org/Publications/rsnanews/June-2009/Medical_Isotope_feature.cfm) JPG A combination of factors must be addressed in order to solve an ongoing, worldwide medical isotope shortage, according to nuclear medicine physicians and radiation oncologists who are being forced to delay or cancel elective—and occasionally even emergency— procedures. Those factors include a virtual halt in U.S. production of medical isotopes, the aging of international reactors with no replacements planned and concerns about the use of highly enriched uranium (HEU) in light of terrorism. "It takes a nuclear reactor to make the medical isotopes in the amounts needed," said James Ponto, M.S., B.N.C.P, a clinical professor of pharmacy and chief nuclear pharmacist at the University of Iowa Hospitals and Clinics in Iowa City. "In nuclear medicine, 80 percent of all imaging uses technetium-99m (Tc99m), which is produced from the decay of the radioisotope molybdenum 99 (Mo-99). Nuclear medicine society SNM estimates that at least 80 percent of the nearly 20 million nuclear medicine procedures each year in the U.S. use Tc-99. The medical isotope can be labeled to a variety of substances that localize in various organs and tissues or otherwise act as tracers of biologic function. Common diagnostic imaging procedures include myocardial perfusion imaging for coronary artery disease and bone imaging to detect spread of cancer to the bones. Other procedures include evaluation of diseases of the kidney, liver and biliary system, lungs, brain and gastrointestinal tract. Since Mo-99 decays with a half-life of 66 hours, pharmacies and hospitals can't stockpile it—once it's gone, it's gone. "A shortage is inevitable if nuclear reactors are shut down," said Ponto. The supply chain of medical isotopes isn’t stable Ponto and Guiberteau 9 (James – M.S., B.N.C.P @ University of Iowa & Milton J – M.D. @ University of Texas Medical School, June 2009, http://www.rsna.org/Publications/rsnanews/June-2009/Medical_Isotope_feature.cfm) JPG There is no reliable domestic supply of Mo-99, said Homer A. Macapinlac, M.D., a professor and chair of the Department of Nuclear Medicine at the University of Texas M.D. Anderson Cancer Center. Instead, five commercial nuclear reactors—located in Canada, The Netherlands, Belgium, France and South Africa—produce 95 percent of the world's supply. 1990 saw the closure of the last U.S. reactor producing Mo-99. Plans to build a new facility in New Mexico were dismissed due to cost concerns, with the thought that Canada could produce medical isotopes at much lower cost—in fact, two reactors had been operating at Chalk River Laboratories in Canada since 1947 and 1957. The 1947 reactor closed in 1992. The other continues to make medical isotopes today; however, the reactor was shutdown in late May due to a water leak and was not expected to be running again for a month. In 2000, Canada built two new facilities to replace the older ones at Chalk River. Technical issues arose, however, as officials sought to fully commission the new reactors and development was halted in May 2008. "The plan that everyone depended upon went away," said Ponto. "It's scary. It's a very fragile system." Both the remaining Chalk River reactor and the Petten reactor in The Netherlands have been shut down several times in the past year for regular maintenance and emergency repairs. "The reactors in Canada and The Netherlands are 40 to 50 years old, said Milton J. Guiberteau, M.D., a professor of clinical radiology at the University of Texas Medical School in Houston. Dr. Guiberteau chairs the Nuclear Medicine Subcommittee of the RSNA Scientific Program Committee. "The reactors are at the outer limits of their useful lives." Global medical isotope supply is dwindling – increased demand causes shortages Kramer 11 (David, MD, specializes in cardiology and internal medicine, February 2011, http://physicstoday.org/resource/1/phtoad/v64/i2/p17_s1) JPG Pressure from the US to eliminate all commercial uses of HEU is occurring against a backdrop of severe shortages in the supply of 99Mo in recent years. There are only five reactors in the world—each around 50 years old—producing material for four processors. A prolonged shutdown of one reactor, as occurred for 15 months at Canada’s National Research Universal (NRU) facility, is sufficient to create havoc with nuclear medicine worldwide (see PHYSICS TODAY, May 2008, page 22 ). The NRU routinely produces 30% of the world’s 99Mo, but it’s capable of generating as much as 80% if necessary, says Jill Chitra, senior vice president for quality and regulatory affairs at Nordion, an Ottawa company that purifies and distributes the NRU’s 99Mo. “There is no reactor in the world that can replace NRU’s capacity,” Chitra asserts. The NRU shutdown was followed by the idling of the second largest reactor source, the High Flux Reactor in Petten, the Netherlands, for more than half of 2010 for scheduled maintenance and repairs. Taken together, the NRU and the HFR account for more than half of the global supply. During their outages, two of Nordion’s competitors, Covidien, which processes 99Mo in the Netherlands, and Belgium’s Institute for Radioelements, found research reactors in Poland and the Czech Republic willing to supply some of the lost isotope. Necsa also stepped up its output during the supply crunch, and at times it was the only producer operating, Robertson says. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 0.87 Mb. Share with your friends:
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