Editing CT scan (section)

==== Excess doses ====
In October, 2009, the US [[Food and Drug Administration]] (FDA) initiated an investigation of brain perfusion CT (PCT) scans, based on [[radiation burn]]s caused by incorrect settings at one particular facility for this particular type of CT scan. Over 200 patients were exposed to radiation at approximately eight times the expected dose for an 18-month period; over 40% of them lost patches of hair. This event prompted a call for increased CT quality assurance programs. It was noted that "while unnecessary radiation exposure should be avoided, a medically needed CT scan obtained with appropriate acquisition parameter has benefits that outweigh the radiation risks."<ref name="Furlow2010">{{Cite book |last=Whaites |first=Eric |url=https://books.google.com/books?id=qdOSDdETuxcC&q=Typical+effective+dose&pg=PA27 |title=Radiography and Radiology for Dental Care Professionals E-Book |date=2008-10-10 |publisher=Elsevier Health Sciences |isbn=978-0-7020-4799-2 |pages=25}}</ref><ref>{{Cite journal |vauthors=Wintermark M, Lev MH |date=January 2010 |title=FDA investigates the safety of brain perfusion CT |journal=AJNR Am J Neuroradiol |volume=31 |issue=1 |pages=2–3 |doi=10.3174/ajnr.A1967 |pmc=7964089 |pmid=19892810 |doi-access=free}}</ref> Similar problems have been reported at other centers.<ref name="Furlow2010" /> These incidents are believed to be due to [[human error]].<ref name="Furlow2010" />