Low-dose Radiation Abdominal Computed Tomography

Study Overview
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Brief Summary
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Purpose: To evaluate the image quality of deep learning-based image reconstruction (DLIR) algorithm in unenhanced abdominal low-dose CT (LDCT). Methods: CT images of a phantom were reconstructed with Hybrid iterative reconstruction and deep learning image reconstruction (DLIR). The noise power spectrum (NPS) and task transfer function (TTF) were measured. Two patient groups were included in this study: consecutive patients who underwent unenhanced abdominal standard-dose CT reconstructed with hybrid iterative reconstruction (SDCT group) and consecutive patients who underwent unenhanced abdominal LDCT reconstructed of HIR and DLIR (LDCT group). The CT values, standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the hepatic parenchyma and paraspinal muscle and abdominal subcutaneous fat were evaluated. Radiologists assessed the subjective image quality and lesion diagnostic confidence using a 5-point Likert scale. Quantitative and qualitative parameters were compared between SDCT and LDCT groups.

Official Title
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Deep Learning Image Reconstruction in Low-dose Radiation Abdominal Computed Tomography: a Comparison of Image Quality and Radiation Dose

Conditions
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CT Examination of the Abdomen

Intervention / Treatment
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* Radiation: CT Radiation Doses


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Abdominal CT examination Exclusion Criteria: pregnancy and lactation for women unstable breath holding

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| SDCT group<br> | |
| LDCT group<br> | Radiation: CT Radiation Doses<br>* Obtaining Low CT Radiation Doses by Adjusting Dose Levels<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Results of phantom research | Compare the changes in spatial resolution (TTF curve) and noise (NPS curve) between different algorithms | up to six months | 
| Results of human clinical study | General information of clinical trial personnel Compare the general information of two groups of subjects, such as age, weight（kg）, height（m）, gender, and BMI (kg/m2). Quantitative image analysis The standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the hepatic parenchyma and paraspinal muscle were evaluated. Qualitative image analysis Two radiologists qualitatively assessed the overall image noise and overall image quality depiction. | up to six months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient demographics | Participant demographics: Age (year)/Gender/Body weight (kg) / Body mass index (kg/m2) | up to six months |