Dose Reduction and Compliance with Pediatric CT Protocols Adapted to Patient Size, Clinical Indication, and Number of Prior Studies

Purpose: To assess compliance and resultant radiation dose reduction with new pediatric chest and abdominal computed tomographic (CT) protocols based on patient weight, clinical indication, number of prior CT studies, and automatic exposure control.

Materials and Methods: The study was institutional review board approved and HIPAA compliant. Informed consent was waived. The new pediatric CT protocols, which were organized into six color zones based on clinical indications and number of prior CT examinations in a given patient, were retrospectively assessed. Scanning parameters were adjusted on the basis of patient weight. For gradual dose reduction, pediatric CT (n = 692) examinations were performed in three phases of incremental stepwise dose reduction during a 17-month period. There were 245 male patients and 193 female patients (mean age, 12.6 years). Two radiologists independently reviewed CT images for image quality. Data were analyzed by using multivariate analysis of variance.

Results: Compliance with the new protocols in the early stage of implementation (chest CT, 58.9%; abdominal CT, 65.2%) was lower than in the later stage (chest CT, 88%; abdominal CT, 82%) (P < .001). For chest CT, there was 52.6% (9.1 vs 19.2 mGy) to 85.4% (2.8 vs 19.2 mGy) dose reduction in the early stage of implementation and 73.5% (4.9 vs 18.5 mGy) to 83.2% (3.1 vs 18.5 mGy) dose reduction in the later stages compared with dose at noncompliant examinations (P < .001); there was no loss of clinically relevant image quality. For abdominal CT, there was 34.3% (9.0 vs 13.7 mGy) to 80.2% (2.7 vs 13.7 mGy) dose reduction in the early stage of implementation and 62.4% (6.5 vs 17.3) to 83.8% (2.8 vs 17.3 mGy) dose reduction in the later stage (P < .001).

Conclusion: Substantial dose reduction and high compliance can be obtained with pediatric CT protocols tailored to clinical indications, patient weight, and number of prior studies.

Supplemental material: http://radiology.rsnajnls.org/cgi/content/full/2521081554/DC1

© RSNA, 2009

References

  • 1 Linton OW, Mettler FA. National conference on dose reduction in CT, with an emphasis on pediatric patients. AJR Am J Roentgenol 2003; 181: 321–329. Crossref, MedlineGoogle Scholar
  • 2 Kalra MK, Maher MM, Toth TL, et al. Strategies for CT radiation dose optimization. Radiology 2004; 230: 619–628. LinkGoogle Scholar
  • 3 One size does not fit all: reducing risks from pediatric CT. ACR Bull 2001; 57: 20–23. Google Scholar
  • 4 Frush DP, Soden B, Frush KS, Lowry C. Improved pediatric multidetector body CT using a size-based color-coded format. AJR Am J Roentgenol 2002; 178: 721–726. Crossref, MedlineGoogle Scholar
  • 5 Rizzo S, Kalra M, Schmidt B, et al. Comparison of angular and combined automatic tube current modulation techniques with constant tube current CT of the abdomen and pelvis. AJR Am J Roentgenol 2006; 186: 673–679. Crossref, MedlineGoogle Scholar
  • 6 McCollough CH, Bruesewitz MR, Kofler JM Jr. CT dose reduction and dose management tools: overview of available options. RadioGraphics 2006; 26: 503–512. LinkGoogle Scholar
  • 7 Greess H, Nömayr A, Wolf H, et al. Dose reduction in CT examination of children by an attenuation-based on-line modulation of tube current (CARE Dose). Eur Radiol 2002; 12: 1571–1576. Crossref, MedlineGoogle Scholar
  • 8 Kalra MK, Maher MM, D'Souza RV, et al. Detection of urinary tract stones at low-radiation-dose CT with z-axis automatic tube current modulation: phantom and clinical studies. Radiology 2005; 235: 523–529. LinkGoogle Scholar
  • 9 Salamipour H, Jimenez RM, Brec SL, et al. Multidetector row CT in pediatric musculoskeletal imaging. Pediatr Radiol 2005; 35: 555–564. Crossref, MedlineGoogle Scholar
  • 10 Chapman VM, Kalra M, Halpern E, et al. 16-MDCT of the posttraumatic pediatric elbow: optimum parameters and associated radiation dose. AJR Am J Roentgenol 2005; 185: 516–521. Crossref, MedlineGoogle Scholar
  • 11 Udayasankar UK, Braithwaite K, Arvaniti M, et al. Low-dose nonenhanced head CT protocol for follow-up evaluation of children with ventriculoperitoneal shunt: reduction of radiation and effect on image quality. AJNR Am J Neuroradiol 2008; 29: 802–806. Crossref, MedlineGoogle Scholar
  • 12 de Jong PA, Nakano Y, Lequin MH, Tiddens HA. Dose reduction for CT in children with cystic fibrosis: is it feasible to reduce the number of images per scan? Pediatr Radiol 2006; 36: 50–53. Crossref, MedlineGoogle Scholar
  • 13 Yi CA, Lee KS, Kim TS, Han D, Sung YM, Kim S. Multidetector CT of bronchiectasis: effect of radiation dose on image quality. AJR Am J Roentgenol 2003; 181: 501–505. Crossref, MedlineGoogle Scholar
  • 14 Remy-Jardin M, Sobaszek A, Duhamel A, et al. Asbestos-related pleuropulmonary diseases: evaluation with low-dose four-detector row spiral CT. Radiology 2004; 233: 182–190. LinkGoogle Scholar
  • 15 Gergely I, Neumann C, Reiger F, Dorffner R. Lung nodule detection with ultra-low-dose CT in routine follow-up of cancer patients [in German]. Rofo 2005; 177: 1077–1083. Crossref, MedlineGoogle Scholar
  • 16 Kalra MK, Maher MM, Kamath RS, et al. Sixteen-detector row CT of abdomen and pelvis: study for optimization of Z-axis modulation technique performed in 153 patients. Radiology 2004; 233: 241–249. LinkGoogle Scholar
  • 17 Kalra MK, Maher MM, Toth TL, et al. Comparison of Z-axis automatic tube current modulation technique with fixed tube current CT scanning of abdomen and pelvis. Radiology 2004; 232: 347–353. LinkGoogle Scholar
  • 18 European guidelines on quality criteria for computed tomography. EUR 16262. http://www.drs.dk/guidelines/ct/quality/index.htm. Accessed April 21, 2008. Google Scholar
  • 19 Westra SJ, Kalra MK, Liu B, Buckley V, Ferris T. Radiation exposure of obese children from body CT: are they appropriately treated as adults? Radiological Society of North America 2007. http://rsna2007.rsna.org/rsna2007/V2007/conference/event_display.cfm?em_id=5008891. Accessed April 20, 2008. Google Scholar
  • 20 Wall BF. Implementation of DRLs in the UK. Radiat Prot Dosimetry 2005; 114: 183–187. Crossref, MedlineGoogle Scholar
  • 21 Shrimpton PC, Hillier MC, Lewis MA, Dunn M. National survey of doses from CT in the UK: 2003. Br J Radiol 2006; 79: 968–980. Crossref, MedlineGoogle Scholar

Article History

Published in print: 2009