Decreasing the effective radiation dose in pediatric craniofacial CT by changing head position
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Published on: September 11, 2011
Ryne A Didier1, Anna A Kuang, Daniel L Schwartz
1School of Medicine, Oregon Health and Science University, Portland, OR 97239, USA.
Insights
Pediatric craniofacial CT scans can reduce radiation dose by 18% by positioning children in an exaggerated sniff position. This technique maintains diagnostic image quality for craniofacial CT (CFCT) evaluations.
Area of Science:
- Medical Imaging
- Pediatric Radiology
- Radiation Dose Reduction
Background:
- Children undergoing craniofacial surgery evaluation are exposed to ionizing radiation.
- Minimizing radiation exposure in pediatric patients is crucial.
Purpose of the Study:
- To decrease effective radiation dose during pediatric craniofacial CT (CFCT) imaging.
- To maintain diagnostic image quality while reducing radiation exposure.
Main Methods:
- A prospective study involved 49 children positioned in an exaggerated sniff position during CFCT.
- The neck extension aimed to shield the cervical spine and thyroid from radiation.
- Image quality and radiation dose were compared to retrospective age-matched controls.
Main Results:
- A statistically significant 18% reduction in effective radiation dose was observed.
- A 16% decrease in z-axis length was noted.
- Diagnostic image quality was maintained, with improved bone windows and 3D reconstructions, despite a slight decrease in brain window quality.
Conclusions:
- Extending the neck during pediatric craniofacial CT imaging is an effective method to reduce radiation dose.
- This positional change maintains diagnostic image quality.
- The exaggerated sniff position offers a viable strategy for safer pediatric craniofacial imaging.
Background:
Children are exposed to ionizing radiation during pre- and post-operative evaluation for craniofacial surgery.
Objective:
The primary purpose of the study was to decrease effective radiation dose while preserving the diagnostic quality of the study.
Materials And Methods:
In this prospective study 49 children were positioned during craniofacial CT (CFCT) imaging with their neck fully extended into an exaggerated sniff position, parallel to the CT gantry, to eliminate the majority of the cervical spine and the thyroid gland from radiation exposure. Image-quality and effective radiation dose comparisons were made retrospectively in age-matched controls (n = 49).
Results:
When compared to CT scans reviewed retrospectively, the prospective examinations showed a statistically significant decrease in z-axis length by 16% (P < 0.0001) and delivered a reduced effective radiation dose by 18% (P < 0.0001). The subjective diagnostic quality of the exams performed in the prospective arm was maintained despite a slight decrease in the quality of the brain windows. There was statistically significant improvement in the quality of the bone windows and three-dimensional reconstructed images.
Conclusion:
Altering the position of the head by extending the neck during pediatric craniofacial CT imaging statistically reduces the effective radiation dose while maintaining the diagnostic quality of the images.
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