Volume 12, Issue 1 (Paramedical Sciences and Military Health (Spring 2017) 2017)                   Paramedical Sciences and Military Health 2017, 12(1): 39-49 | Back to browse issues page

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Study the Effect of Gantry Tilting and Tube Voltage Reducing on the Eye Lens Dose Reduction in Computed Tomography Using MCNPx
Seyed Salman Zakariaee1 , Valiallah Saba 2, Abdollah Valizadeh1
1- Department of Radiology, Faculty of Paramedicine, AJA University of Medical Sciences, Tehran, Iran
2- Department of Radiology, Faculty of Paramedicine, AJA University of Medical Sciences, Tehran, Iran , vsaba@aut.ac.ir
Abstract:   (5772 Views)

Introduction: Eye lens is a very sensitive organ to the x-ray radiation and cataract could be formed as a result of eye exposure. Computed tomography (CT) is one of the main exposure sources in clinical situations and brain imaging delivers high amount of exposure to the eye lens. To reduce eye lens dose, efficient dose reduction methods have to be developed and implemented. In this paper, the efficiency of two methods including gantry tilting and kVp reduction, have been studied for eye lens dose reduction.
Methods and Materials: A 64-slice CT scanner was modeled to evaluate the eye lens dose in different scanning arrangements using MCNPx. To study the effect of kVp reduction and gantry tilting on the Lens dose magnitudes, three tube voltages including 100, 120 and 140 kVp and three gantry tilts including 0, 15 and 30 degrees were simulated and studied.
Results: The results showed that the lens dose considerably decreased by tube voltage decreasing and gantry tilt increasing.
Discussion and Conclusion: From the results, it could be concluded that low tube voltage and gantry tilting are effective and simple methods for lens dose reduction in CT scan.

Keywords: Computer tomography, Lens dose reduction methods, Gantry tilt, X-ray tube voltage, Monte Carlo
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Type of Study: Research | Subject: full articles
Received: 2017/05/10 | Accepted: 2017/05/20 | Published: 2017/06/18
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