title: Evaluation of X-Ray Beam Quality Based on Measurements and Estimations Using SpekCalc and Ipem78 Models.
abstract: BACKGROUND
  Different computational methods have been used for the prediction of X-ray spectra and beam quality in diagnostic radiology. The purpose of this study was to compare X-ray beam qualities based on half-value layers (HVLs) determined through measurements and computational model estimations.
  
  
  METHODS
  The HVL estimations calculated by IPEM78 (Spectrum Processor of the Institute of Physics and Engineering in Medicine's Report 78) and SpekCalc software were compared with those determined through measurements. In this study, the HVLs of both Philips (Phil) (Philips Healthcare, Best, NL) and General Electric Company (GE) (GE Global Research, Niskayuna, US) diagnostic range X-ray machines (50 kVp to 125 kVp) were evaluated.
  
  
  RESULTS
  In the HVL estimations, SpekCalc and IPEM78 showed maximum differences of 10% and 9%, respectively, compared with direct measurements. Both models provided means and SDs of HVLs that were within 5% of the HVL measurements of GE and Phil machines.
  
  
  CONCLUSIONS
  Both computational models provide an alternative method for estimating the HVL of diagnostic range X-ray. These models are user-friendly in predicting HVLs, which are used to characterise the quality of the X-ray beam, and these models provide predictions almost instantly compared with experimental measurements.
authors.affiliation: Medical Radiation Programme, School of Health Sciences, Universiti Sains Malaysia, Health Campus, 16150 Kubang Kerian, Kelantan, Malaysia.
authors.forename: Suk Chiang
authors.initials: SC
authors.lastname: Chen
authors.forename: Wei Loong
authors.initials: WL
authors.lastname: Jong
authors.forename: Ahmad Zaky
authors.initials: AZ
authors.lastname: Harun
keywords: HVL; IPEM78; SpekCalc; beam quality; effective energy