Optimizing the Radiation Dose for CT Imaging With Iterative Reconstruction in Diagnosing Acute Appendicitis: Dose Simulation Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 30
- 试验地点
- 1
- 主要终点
- Diagnostic performance at original dose (2 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist
研究概览
简要总结
The study will explore CT radiation dose as low as reasonably achievable in diagnosing acute appendicitis, by using of dose simulation technique and iterative reconstruction.
详细描述
Three sequential non-inferiority tests are planned. First, three readers will review the original 2-mSv images. Second, the readers will review the 75%-dose images. After the readers review the 75%-dose images and before the readers reviewed the 50%-dose images, the non-inferiority of 75% dose to the original dose will be tested. If the non-inferiority is not accepted, the study will be terminated with the conclusion of 2 mSv as the lowest acceptable dose. If the non-inferiority is accepted, the study will be continue to the next step. In the same manner, the readers will review the next lower-dose images (50% and then 25%), and then the noninferiority will be tested against the original dose.
研究设计
- 研究类型
- Observational
- 观察模型
- Other
- 时间视角
- Prospective
入排标准
- 年龄范围
- 15 Years 至 44 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •18-44 years of age.
- •Emergency department visit with suspected symptoms and signs of acute appendicitis
- •Intravenous contrast-enhanced computed tomography examination requested due to suspicion of appendicitis
排除标准
- •having contraindications of intravenous contrast agent
结局指标
主要结局
Diagnostic performance at original dose (2 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist
时间窗: 2 months
The pooled area under curve (AUC) from three radiologists
Diagnostic performance at 75% dose (1.5 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist
时间窗: 1 months
The pooled AUC from three radiologists
Diagnostic performance at 50% dose (1.0 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist
时间窗: 8 months
\*The analysis of 50%-dose CT images will be performed only if non-inferiority of 75%-dose CT to the original CT is proven in terms of the pooled AUC. The pooled AUC from three radiologists
Diagnostic performance at 25% dose (0.5 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist
时间窗: 14 months
\*The analysis of 25%-dose CT images will be performed only if non-inferiority of 50%-dose CT is proven to the original CT in terms of the pooled AUC. The pooled AUC from three radiologists
次要结局
- Diagnostic confidence in diagnosing and ruling out appendicitis at original CT: the likelihood score for appendicitis(2 months)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 75%-dose CT: the likelihood score for appendicitis(1 month)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 50%-dose CT: the likelihood score for appendicitis(8 month)
- Sensitivity at original dose (2 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(2 months)
- Sensitivity at 75% dose (1.5 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(1 month)
- Sensitivity at 50% dose (1.0 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(8 months)
- Specificity at 50% dose (1.0 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(8 months)
- Specificity at 25% dose (0.5 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(14 months)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 25%-dose CT: normal appendix visualization rate(14 months)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 75%-dose CT: indeterminate CT interpretation(1 month)
- Specificity at original dose (2 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(2 months)
- Sensitivity at 25% dose (0.5 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(14 months)
- Specificity at 75% dose (1.5 mSv) using 5-grade Likert score for the likelihood of appendicitis assigned by each radiologist(1 month)
- Diagnostic confidence in diagnosing and ruling out appendicitis at original CT: normal appendix visualization rate(2 month)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 25%-dose CT: the likelihood score for appendicitis(14 month)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 75%-dose CT: normal appendix visualization rate(1 month)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 50%-dose CT: normal appendix visualization rate(8 months)
- Diagnostic confidence in diagnosing and ruling out appendicitis at original CT: indeterminate CT interpretation(2 months)
- Alternative diagnoses at 25%-dose CT: the radiologists will record possible alternative diagnosis if the patients are presumed to be not having appendicitis(14 months)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 50%-dose CT: indeterminate CT interpretation(8 months)
- Diagnostic confidence in diagnosing and ruling out appendicitis at 25%-dose CT: indeterminate CT interpretation(14 months)
- Alternative diagnoses at original CT: the radiologists will record possible alternative diagnosis if the patients are presumed to be not having appendicitis(2 months)
- Alternative diagnoses at 50%-dose CT: the radiologists will record possible alternative diagnosis if the patients are presumed to be not having appendicitis(8 months)
- Alternative diagnoses at 75%-dose CT: the radiologists will record possible alternative diagnosis if the patients are presumed to be not having appendicitis(1 month)
研究者
Ji Hoon Park
Assistant professor
Seoul National University Bundang Hospital