Low-dose CT imaging of the acute abdomen using model-based iterative reconstruction: a prospective study

Area of Science:

• Radiology
• Medical Imaging
• Radiation Dose Reduction

Background:

• Abdominopelvic CT is crucial for diagnosing acute abdominal conditions.
• Conventional CT protocols involve significant radiation exposure.
• Iterative reconstruction (IR) techniques offer potential for dose reduction.

Purpose of the Study:

• To evaluate the performance of a modified low-dose (LD) abdominopelvic CT protocol reconstructed with model-based iterative reconstruction (MBIR).
• To compare image quality and diagnostic accuracy between LD-MBIR and conventional-dose (CD) CT with adaptive statistical iterative reconstruction (ASIR).

Main Methods:

• Prospective study of 57 patients undergoing abdominopelvic CT for acute symptoms.
• Acquisition of both LD and CD CT datasets.
• LD images reconstructed with MBIR; CD images with hybrid IR (40% ASIR).
• Quantitative and qualitative image quality assessment, including noise, contrast resolution, and artifacts.

Main Results:

• Achieved a 74.7% mean radiation dose reduction with LD-MBIR.
• LD-MBIR demonstrated significantly lower image noise compared to CD-ASIR (p < 0.0001).
• CD-ASIR showed better contrast resolution and diagnostic acceptability (p < 0.0001).
• LD-MBIR had significantly lower streak artifacts (p < 0.0001).
• No significant difference in sensitivity for primary findings, except for one case of enteritis.

Conclusions:

• Low-dose abdominopelvic CT with MBIR is a feasible radiation dose reduction strategy.
• This protocol effectively images patients with acute abdominal pain while minimizing radiation exposure.
• MBIR reconstruction enhances image quality in low-dose CT protocols.