Usefulness of Large Beam-shaping Filters at Different Tube Voltages of Newborn Chest CT

Overview

Journal Phys Eng Sci Med

Publisher Springer

Specialty Biomedical Engineering

Date 2023 Jan 12

PMID 36633769

Authors

Takanori Masuda

Yoshinori Funama

Takeshi Nakaura

Tomoyasu Sato

Kotaro Urayama

Masao Kiguchi

Takayuki Oku

Masato Yoshida

Shinichi Arao

Atsushi Ono

Junichi Hiratsuka

Kazuo Awai

Affiliations

Soon will be listed here.

Abstract

Background: To investigate optimizing the use of different beam shaping filters (viz. small, medium and large) when using different tube voltages during the newborn chest computed tomography (CT) on a GE Lightspeed VCT scanner.

Methods: We used pediatric anthropomorphic phantoms with a 64 detector-row CT scanner while scanning the chest. A real-time skin dosimeter (RD - 1000; Trek Corporation, Kanagawa, Japan) was positioned into the phantom center of the body, the surface of the body back, and the right and left mammary glands. We performed and compared six scan protocols using small, medium, and large beam shaping filters at 80 and 120 kVp protocols.

Result: There were no significant differences in the image noise for the chest scan among the different beam shaping filters. By using the large beam shaping filter at 80 kVp, it was possible to reduce the exposure dose by 5% in comparison with the small beam shaping filter, and by 10% in comparison with the medium beam shaping filter. By using the large beam shaping filter at 120 kVp, it was possible to reduce the exposure dose by 15% in comparison with the small beam shaping filter and by 20% in comparison with the medium beam shaping filter (p < 0.01).

Conclusion: The large beam shaping filter had the most dose reduction effect during newborn chest CT on a GE Lightspeed VCT scanner. The additional copper filtration being present in the large bowtie filter of the GE Lightspeed CT scanner when using different tube voltages is more effective in reducing radiation exposure in children.

References

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

Broder J, Fordham L, Warshauer D . Increasing utilization of computed tomography in the pediatric emergency department, 2000-2006. Emerg Radiol. 2007; 14(4):227-32. DOI: 10.1007/s10140-007-0618-9. View

Preston D, Ron E, Tokuoka S, Funamoto S, Nishi N, Soda M . Solid cancer incidence in atomic bomb survivors: 1958-1998. Radiat Res. 2007; 168(1):1-64. DOI: 10.1667/RR0763.1. View

Miglioretti D, Johnson E, Williams A, Greenlee R, Weinmann S, Solberg L . The use of computed tomography in pediatrics and the associated radiation exposure and estimated cancer risk. JAMA Pediatr. 2013; 167(8):700-7. PMC: 3936795. DOI: 10.1001/jamapediatrics.2013.311. View

Mathews J, Forsythe A, Brady Z, Butler M, Goergen S, Byrnes G . Cancer risk in 680,000 people exposed to computed tomography scans in childhood or adolescence: data linkage study of 11 million Australians. BMJ. 2013; 346:f2360. PMC: 3660619. DOI: 10.1136/bmj.f2360. View

Schiska A . Teaching Radiography Students the ALARA Principle. Radiol Technol. 2021; 93(2):228-231. View

Masuda T, Funama Y, Kiguchi M, Imada N, Oku T, Sato T . Radiation dose reduction based on CNR index with low-tube voltage scan for pediatric CT scan: experimental study using anthropomorphic phantoms. Springerplus. 2016; 5(1):2064. PMC: 5133217. DOI: 10.1186/s40064-016-3715-y. View

Masuda T, Funama Y, Kiguchi M, Osawa K, Suzuki S, Oku T . Relationship between the radiation doses at nonenhanced CT studies using different tube voltages and automatic tube current modulation during anthropomorphic phantoms of young children. J Appl Clin Med Phys. 2017; 18(6):232-243. PMC: 5689931. DOI: 10.1002/acm2.12192. View

Masuda T, Funama Y, Nakaura T, Sato T, Tahara M, Takei Y . USE OF VACUUM MATTRESSES CAN REDUCE THE ABSORBED DOSE DURING PEDIATRIC CT. Radiat Prot Dosimetry. 2021; 194(4):201-207. DOI: 10.1093/rpd/ncab102. View

10.

Funama Y, Awai K, Nakayama Y, Kakei K, Nagasue N, Shimamura M . Radiation dose reduction without degradation of low-contrast detectability at abdominal multisection CT with a low-tube voltage technique: phantom study. Radiology. 2005; 237(3):905-10. DOI: 10.1148/radiol.2373041643. View

11.

Toth T . Dose reduction opportunities for CT scanners. Pediatr Radiol. 2002; 32(4):261-7. DOI: 10.1007/s00247-002-0678-7. View

12.

Kalra M, Maher M, Toth T, Hamberg L, Blake M, Shepard J . Strategies for CT radiation dose optimization. Radiology. 2004; 230(3):619-28. DOI: 10.1148/radiol.2303021726. View

13.

Rogers L . Radiation exposure in CT: why so high?. AJR Am J Roentgenol. 2001; 177(2):277. DOI: 10.2214/ajr.177.2.1770277. View

14.

Frush D, Applegate K . Computed tomography and radiation: understanding the issues. J Am Coll Radiol. 2007; 1(2):113-9. DOI: 10.1016/j.jacr.2003.11.012. View

15.

DAY F, TAYLOR L . Absorption of X-rays in air. Radiology. 1949; 52(2):239-47. DOI: 10.1148/52.2.239. View