Abstract: A calibration phantom for quality assurance of an image-based radiotherapy apparatus The calibration phantom includes a body comprising a cylindrical acryl member having a predetermined diameter, the body having a center hole at a center axis thereof and a plurality of through-holes in outer circumferential portions thereof at a predetermined interval from the center hole; round stick-type density bars inserted into corresponding through-holes of the body and made of materials each with different densities; an acrylic cover detachably coupled with both ends of the body and having the same diameter as the body; and a plurality of bolts closely fastening the body with the cover by extending through the cover and the body and coupling with the nuts and each made of different materials. The cross-sectional shapes of the density bars and bolts appear on the image scanned by the CT apparatus and the radiotherapy apparatus.

Abstract: A calibration phantom for quality assurance of an image-based radiotherapy apparatus The calibration phantom includes a body comprising a cylindrical acryl member having a predetermined diameter, the body having a center hole at a center axis thereof and a plurality of through-holes in outer circumferential portions thereof at a predetermined interval from the center hole; round stick-type density bars inserted into corresponding through-holes of the body and made of materials each with different densities; an acrylic cover detachably coupled with both ends of the body and having the same diameter as the body; and a plurality of bolts closely fastening the body with the cover by extending through the cover and the body and coupling with the nuts and each made of different materials. The cross-sectional shapes of the density bars and bolts appear on the image scanned by the CT apparatus and the radiotherapy apparatus.