Radiation Exposure in Thoracic CT

摘要: Helical or spiral CT has revolutionized X-ray-based diagnostic medical imaging in the past 15 years (Berland and Smith 1998; Kalender Polacin 1991; et al. 1990; Remy-Jardin 2001). Introduced late 1980s, single and, more recently, multidetector-row scanners have greatly expanded clinical indications demand for scans of thorax. This led to a considerable increase number examinations average scanned volume obtained per examination. inevitably an radiation exposure delivered by these studies. The increased utilization been documented studies USA UK that found approximately twofold between 1980s 1990s (Mettler 2000; Shrimpton Edyvean 1991). A recent report from American academic institution showed formed 11.1% radiologic procedures 1999 compared with 6.1% 1990 2000). Because is relatively high-radiation-dose technique, authors reported 67% total effective dose radiology 1999. study also noted 11% were performed pediatric population, which was higher than previously estimated high survey 1989 accounted 2% radiographic 20% (Shrimpton follow-up 1995 now 4% all 1998) 40% dose. population examinations, particularly children, concern radiologists, physicists, government regulators, media (Sternberg suggestion excessive doses are being prescribed appropriately aroused attention community (Rogers We must be attentive our responsibility maintain appropriate balance image quality (Nickoloff Alderson It suggested rapid expansion thoracic issues may not received adequate (Golding 2002). chapter reviews (a) measurement units used quantify exposure, (b) parameters affect effi ciency, (c) advances reduction chest CT. Radiation dosimetry bioeffects addressed detail interested readers referred complete works areas 2002; Huda Atherton 1995; Jones 1992; Mettler Upton Metz 1995).