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An Efficient Correction Process of CT-Simulator Couch with Current Diagnostic CT Scanners

진단용 CT-모의치료기 테이블의 효율적인 교정 방법

  • 구은회 (순천향대학교 물리학과) ;
  • 이재승 (순천향대학교 물리학과) ;
  • 조정근 (전주대학교 방사선학과) ;
  • 문성권 (순천향대학교 부천병원 방사선종양학과)
  • Published : 2009.11.28

Abstract

This study suggested that the table of CT-simulator and the laser alignment system using diagnostic CT scanner have an efficient method for improvement in alignment between the planned target center of traverse image with CT scanner. It was conducted on the daily QA when presented in the AAPM TG66 with correcting the laser alignment system using geometric trigonometric functions and investigated the effectiveness of correction methods as compared with those before and after correction. Before correction error was 3.82mm between the planned target center of image, the table longitudinal axis was twisted with 0.436o. The laser alignment system using geometric trigonometric functions in after correction was satisfied with tolerance limits of ${\pm}2mm$ when occurred about 0.7mm in errors between the planned target center. The table correction to satisfy the geometric accuracy is very inefficient over against the time and economic loss as well as technical limits in the case of application as only radiation therapy associated with CT-simulator with diagnostic CT scanner in use. But, the method which corrects the laser alignment system is economic and relatively simple with possibility of getting well geometric accuracy and we suppose that it is efficient method for applying in the clinic.

Keywords

Computed Tomography(CT);CT-Simulator;AAPM TG66;Quality Assurance;Laser Alignment System

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