silverfast epson expression 10000xl it8 calibration

#Silverfast epson expression 10000xl it8 calibration how to#
#Silverfast epson expression 10000xl it8 calibration verification#

The usefulness of Gafchromic ® RTQA2 as a tool to implement a reproducible protocol for quality control (QC) on leaf positioning accuracy in MLC, both quantitatively and qualitatively, was evaluated in this investigation. The RTQA films also represent a valid detector to realize quality assurance (QA) on beam parameters: Thomas and Warrington found that it's possible to determine the position of field edges using RTQA films and a flatbed scanner. ,, , Majority of these works used Gafchromic ® EBT films and subsequent upgrades high spatial resolution is their most important feature.

#Silverfast epson expression 10000xl it8 calibration verification#

Many studies on the use of radiochromic films for dosimetry in clinical photon beams for the implementation or verification of IMRT technique was performed. Gafchromic ® films (International Speciality Products, Wayne, New Jersey) have a wide use for dosimetric purposes in radiotherapy applications. These checks can be performed with different types of detectors, such as diodes arrays, ionization chamber arrays, electronic portal image devices (EPID), or radiochromic films. For 1 mm deviation, this discrepancy was reduced to 8%. Sharpe et al., demonstrated that largest output factors differences are seen when the actual field size deviates from the set field size: e.g., the measured output can vary by as much as 16% for 1 × 1 cm 2 field size compared with 10 × 10 cm 2, when the measured field size deviates from the set field size by 2 mm.

For this reason, controls should be performed to verify leaves and jaws settings when using several small fields, both during acceptance and subsequent controls. Intensity-modulated radiation therapy (IMRT) technique requires detailed verification of the multileaf collimator (MLC) leaves position, because geometric discrepancies between planned and actual beam segments affect the treatment quality, as demonstrated in literature both in terms of spatial and dosimetric errors. Implementation of a program for quality assurance on leaf positioning accuracy using Gafchromic ® RTQA2 films.

#Silverfast epson expression 10000xl it8 calibration how to#

How to cite this URL: Girardi A, Anglesio S, Amadore G, Trevisiol E, Redda MR.

How to cite this article: Girardi A, Anglesio S, Amadore G, Trevisiol E, Redda MR. Keywords: Film, gafchromic, IMRT, MLC, quality assurance, RTQA The results suggest that Gafchromic ® RTQA2 films represent a reliable tool to perform MLC routine QA. The picket fence test shows that the method is able to detect displacements equal to 1 mm. Moreover, a qualitative test was performed: A garden picket fence field, consisting in multiple segments 2 × 22 cm 2, was realized setting known leaves shifts to test the method sensitivity. The reproducibility and global uncertainty of the method were estimated to be equal to 0.5% and 0.6 mm, respectively. The images quantitative analysis was handled with a program developed in MATLAB to evaluate the differences between expected and measured leaves positions. To evaluate the leaf positioning accuracy in different conditions, a rhomboidal shape and a field consisting in three rectangular segments were selected. RTQA2 films were irradiated with 6 MV X-rays at different dose levels to obtain calibration curve. A flatbed document scanner (Epson 10000XL) was used in conjunction with radiochromic detector a scanning protocol was firstly defined to improve readout accuracy. The aim of this study is the implementation of a method using Gafchromic ® RTQA 2 films to perform routine QA on the MLC, both for qualitative and quantitative analysis. In radiotherapy treatments the correct dose delivery to the target volume and the consequent conservation of healthy tissues is affected by multileaf collimator (MLC) leaf positioning accuracy and reproducibility, mostly in intensity-modulated radiation therapy (IMRT): For this reason a quality assurance (QA) program is necessary to ensure the best treatment possible to each patient.