A Manufacturer's Role in Reducing the Dose of Cone Beam Computed Tomography Examinations: Effect of Beam Filtration

Overview

Journal Dentomaxillofac Radiol

Publisher Oxford University Press

Date 2011 Jan 18

PMID 21239575

Citations 18

Authors

J B Ludlow

Affiliations

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Abstract

Objectives: The dosimetry of the Kodak 9500 cone beam CT (CBCT) unit (Carestream Health, Rochester, NY) was measured before and after installation of copper filtration.

Methods: Dosimetry of a pre-production Kodak 9500 CBCT unit was compared with a current production unit with 0.4 mm of added filtration and increased kVp. Thermoluminescent dosimeter 100 chips were placed at 24 locations in a RANDO (radiation analogue dosimetry) head phantom (Nuclear Associates, Hicksville, NY). Small, medium and large adult default exposure settings were used in separate dosimeter runs for large and medium field of view (FOV) examinations with both units. Equivalent dose and effective dose were calculated using International Commission on Radiological Protection (ICRP) 1990 and 2007 tissue weights.

Results: Estimations of risk using 2007 ICRP calculations increased by an average of 77% for large FOV scans and 125% for the medium FOV scans in comparison with 1990 calculations. With added filtration, effective dose for medium FOV examinations for default settings were: small adult 76 µSv, medium adult 98 µSv, and large adult 166 µSv. Effective doses for large FOV examinations were: small adult 93 µSv, medium adult 163 µSv, and large adult 260 µSv. Effective dose was reduced by an average of 43% in examinations made with increased filtration and adjusted kVp.

Conclusion: The manufacturer's installation of additional filtration with the adjustment of kVp in the Kodak 9500 CBCT unit resulted in significant patient dose reductions for examinations at all adult default settings.

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References

de Vos W, Casselman J, Swennen G . Cone-beam computerized tomography (CBCT) imaging of the oral and maxillofacial region: a systematic review of the literature. Int J Oral Maxillofac Surg. 2009; 38(6):609-25. DOI: 10.1016/j.ijom.2009.02.028. View

Ludlow J, Davies-Ludlow L, White S . Patient risk related to common dental radiographic examinations: the impact of 2007 International Commission on Radiological Protection recommendations regarding dose calculation. J Am Dent Assoc. 2008; 139(9):1237-43. DOI: 10.14219/jada.archive.2008.0339. View

Brenner D, Hall E . Computed tomography--an increasing source of radiation exposure. N Engl J Med. 2007; 357(22):2277-84. DOI: 10.1056/NEJMra072149. View

Ludlow J, Ivanovic M . Comparative dosimetry of dental CBCT devices and 64-slice CT for oral and maxillofacial radiology. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008; 106(1):106-14. DOI: 10.1016/j.tripleo.2008.03.018. View

Ludlow J, Davies-Ludlow L, Brooks S . Dosimetry of two extraoral direct digital imaging devices: NewTom cone beam CT and Orthophos Plus DS panoramic unit. Dentomaxillofac Radiol. 2003; 32(4):229-34. DOI: 10.1259/dmfr/26310390. View

Smith-Bindman R, Lipson J, Marcus R, Kim K, Mahesh M, Gould R . Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer. Arch Intern Med. 2009; 169(22):2078-86. PMC: 4635397. DOI: 10.1001/archinternmed.2009.427. View

Ludlow J, Davies-Ludlow L, Brooks S, Howerton W . Dosimetry of 3 CBCT devices for oral and maxillofacial radiology: CB Mercuray, NewTom 3G and i-CAT. Dentomaxillofac Radiol. 2006; 35(4):219-26. DOI: 10.1259/dmfr/14340323. View

White S, Rose T . Absorbed bone marrow dose in certain dental radiographic techniques. J Am Dent Assoc. 1979; 98(4):553-8. DOI: 10.14219/jada.archive.1979.0113. View

. The 2007 Recommendations of the International Commission on Radiological Protection. ICRP publication 103. Ann ICRP. 2007; 37(2-4):1-332. DOI: 10.1016/j.icrp.2007.10.003. View

10.

Underhill T, Chilvarquer I, Kimura K, Langlais R, McDavid W, Preece J . Radiobiologic risk estimation from dental radiology. Part I. Absorbed doses to critical organs. Oral Surg Oral Med Oral Pathol. 1988; 66(1):111-20. DOI: 10.1016/0030-4220(88)90077-1. View

11.

. 1990 Recommendations of the International Commission on Radiological Protection. Ann ICRP. 1991; 21(1-3):1-201. View