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Published on: September 11, 2011
Effect of focused protocol on reducing radiation dose for children who require computed tomography for suspected
Suzanne Roberts1, Bernard Goldwasser2, Abigail F Nixon1
1Department of Pediatrics, Division of Emergency Medicine, Jacobi Medical Center, Bronx, NY, United States of America.
Insights
A new height-based Focused CT protocol significantly lowers radiation exposure for children with suspected appendicitis. This focused approach maintains diagnostic accuracy while reducing radiation doses compared to standard CT scans.
Area of Science:
- Pediatric Radiology
- Medical Imaging
- Radiation Safety
Background:
- Computed tomography (CT) is crucial for diagnosing appendicitis in children but involves significant radiation exposure.
- Ultrasound is often used, but CT remains vital for definitive diagnosis.
- A height-based Focused CT protocol was implemented to mitigate radiation risks.
Purpose of the Study:
- To compare the radiation dose administered to pediatric patients undergoing a Standard CT Abdomen and Pelvis (CTAP) versus a Focused CT for suspected appendicitis.
- To evaluate the diagnostic efficacy of both CT protocols.
Main Methods:
- A retrospective study analyzed 474 children (<18 years) who underwent CT for suspected appendicitis between 2014-2020.
- Radiation doses were calculated using the dose-length product, with analyses adjusted for CT dose index volume (CTDIvol) and size-specific dose estimate (SSDE).
- Compared effective radiation doses between Standard CTAP and Focused CT groups.
Main Results:
- The Focused CT identified the appendix in 92% of cases, compared to 84% for Standard CTAP (p=0.02).
- Children receiving the Focused CT experienced a significantly lower effective radiation dose (CTDI-adjusted -13%; SSDE-adjusted -14%) compared to Standard CTAP.
- 165 patients (35%) underwent Focused CT, while 309 (65%) had Standard CTAP.
Conclusions:
- The height-based Focused CT protocol effectively reduces radiation exposure in pediatric appendicitis evaluations.
- Diagnostic accuracy is preserved with the Focused CT protocol.
- Further multi-institutional validation of this protocol is recommended.
Background:
Despite efforts to incorporate ultrasound into the evaluation of children for appendicitis, computed tomography (CT) is often used to aid in its diagnosis. CT scans, however, expose children to a considerable amount of radiation. In 2017, our institution began using a height-based Focused CT protocol for children with suspected appendicitis in need of CT.
Objective:
To compare the radiation dose received by children with suspected appendicitis who underwent a Standard CT of the abdomen and pelvis (CTAP) with that of a Focused CT.
Methods:
We conducted a retrospective study of children <18 years who underwent a CT scan for suspected appendicitis (2014-2020). We included all patients whose indication for CT was "appendicitis" or "right lower quadrant pain" and excluded those whose CT scan record lacked a radiation dose report. The effective radiation dose delivered was calculated using the dose-length product from the dose report. We compared the effective dose of those who received a Standard CTAP to those who received a Focused CT. To account for differences in radiation dose over time and by CT scanner, analyses were adjusted for CT dose index volume (CTDIvol) and size-specific dose estimate (SSDE) using quantile regression.
Results:
A total of 474 patients who underwent CT were included. Prior to CT, 362(76%) had received an ultrasound. In total, 309(65%) patients underwent a Standard CTAP and 165(35%) underwent a Focused CT. The appendix was identified in 259(84%) Standard CTAPs compared to 151(92%) Focused CTs (p = 0.02). Compared to the Standard CTAP, children who received a Focused CT were exposed to a significantly lower effective dose (relative difference: CTDI-adjusted -13%[95% CI:-21,-5]; SSDE-adjusted -14%[95% CI:-24,-3]).
Conclusions:
Our height-based Focused CT protocol reduces radiation for children undergoing CT evaluation for suspected appendicitis without sacrificing diagnostic accuracy. Further study is needed to validate these findings at other institutions.
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