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Updated: Jun 9, 2026
08:30
X-ray Dose Reduction through Adaptive Exposure in Fluoroscopic Imaging
Published on: September 11, 2011
Method for reducing noise in X-ray images by averaging pixels based on the normalized difference with the relevant
Masayuki Nishiki1, Kunio Shiraishi, Takuya Sakaguchi
1Toshiba Medical Systems Corporation, Otawara, Tochigi, Japan. masayuki.nishiki@toshiba.co.jp
Radiological Physics and Technology
|September 8, 2010
Summary
A novel digital filter significantly reduces noise in X-ray images by averaging similar pixels. This noise reduction in medical imaging enhances image quality and potentially lowers patient radiation dose.
Area of Science:
- Medical Imaging
- Digital Signal Processing
Background:
- X-ray imaging is crucial for medical diagnosis.
- Image noise degrades diagnostic quality and can necessitate higher radiation doses.
- Conventional filters may compromise image quality while reducing noise.
Purpose of the Study:
- To develop and evaluate a real-time digital filter for noise reduction in X-ray images.
- To assess the filter's impact on image quality metrics and potential for dose reduction.
Main Methods:
- A novel filter algorithm averaging similar pixels was implemented.
- Computer simulations processed X-ray images using the new filter.
- Evaluated using modulation transfer function (MTF), noise power spectrum (NPS), and lag.
Main Results:
- The filter reduced noise power spectrum across all spatial frequencies.
- Total noise power decreased to approximately 1/9th of the original level.
- No degradation in modulation transfer function (MTF) or lag was observed.
Conclusions:
- The proposed filter effectively reduces noise in X-ray images without compromising image quality.
- Demonstrated utility in fluoroscopy, digital subtraction angiography (DSA), and mammography.
- Potential to reduce patient radiation dose by improving noise reduction in dynamic and static imaging.
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