Study new reconstruction algorithm to decrease the dose of chest computed tomography

Dr Nguyen Dao Cam Tu1, Dr Nguyen Phuoc Bao Quan2
1 Imaging dept - Hue University of Medicine and Pharmacy
2 Department of Functional Exploration – Hue central hospital

Main Article Content

Abstract

Purpose: To Investigate extent of radiation dose reduction in chest CT scaner using an Iterative Reconstruction Technique.
Methods: Image quality and radiation dose (dose length product and CT dose index, effective dose) were restrospectively
reviewed in 60 CT examination of 60 patients who were underwent the lung screening. Standard Dose CT (SDCT) group considered as control were performed at 100kV and 120 mAs of reference; Low dose CT (LDCT) group were done at 100kV and 50 mAs of reference. We apply the technique of automatic mA modulation – CAREdoseTM in both group. The filtered back projection was applied for SDCT, the itirative reconstruction algorithm was used for LDCT.
Results: Compare whith SDCT, LDCT have the radiation exposure reduction with CTDIvol = 1.69 ± 0.56 mGy (decrease
60%), DLP = 54.67 ± 15.99 mGy.cm (decrease 65%), Effective dose = 0.76 ± 0.22mSv (decrease 65%), (p < 0.001). There was
no the difference in quality image between 2 groups (p > 0.05).


Conclusion:The low-dose CT protocol yields a significant reduction in radiation exposure while maintaining the quality
image, safety and precision. Iritative reconstruction plays an important role to improve the quality image.

Article Details

References

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