title: A systematic procedure to optimise dose and image quality for the measurement of inter-vertebral angles from lateral spinal projections using Cobb and superimposition methods.
abstract: BACKGROUND
  Patients with vertebral column deformations are exposed to high risks associated with ionising radiation exposure. Risks are further increased due to the serial X-ray images that are needed to measure and asses their spinal deformation using Cobb or superimposition methods. Therefore, optimising such X-ray practice, via reducing dose whilst maintaining image quality, is a necessity.
  
  
  OBJECTIVE
  With a specific focus on lateral thoraco-lumbar images for Cobb and superimposition measurements, this paper outlines a systematic procedure to the optimisation of X-ray practice.
  
  
  METHODS
  Optimisation was conducted based on suitable image quality from minimal dose. Image quality was appraised using a visual-analogue-rating-scale, and Monte-Carlo modelling was used for dose estimation. The optimised X-ray practice was identified by imaging healthy normal-weight male adult living human volunteers.
  
  
  RESULTS
  The optimised practice consisted of: anode towards the head, broad focus, no OID or grid, 80 kVp, 32 mAs and 130 cm SID.
  
  
  CONCLUSIONS
  Images of suitable quality for laterally assessing spinal conditions using Cobb or superimposition measurements were produced from an effective dose of 0.05 mSv, which is 83% less than the average effective dose used in the UK for lateral thoracic/lumbar exposures. This optimisation procedure can be adopted and use for optimisation of other radiographic techniques.
authors.affiliation: Prosthetics and Orthotics Department, The University of Jordan, Amman, Jordan Centre for Health Sciences Research, University of Salford, Salford, UK.
authors.forename: Bashar
authors.initials: B
authors.lastname: Al Qaroot
authors.affiliation: Centre for Health Sciences Research, University of Salford, Salford, UK.
authors.forename: Peter
authors.initials: P
authors.lastname: Hogg
authors.affiliation: Centre for Health Sciences Research, University of Salford, Salford, UK United National Institute for Prosthetics {\&} Orthotics Development, University of Salford, Salford, UK.
authors.forename: Martin
authors.initials: M
authors.lastname: Twiste
authors.affiliation: Centre for Health Sciences Research, University of Salford, Salford, UK School of Computing, Science {\&} Engineering, University of Salford, Salford, UK.
authors.forename: David
authors.initials: D
authors.lastname: Howard
mesh_terms: D000293:Adolescent; D000328:Adult; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008297:Male; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000295:instrumentation / Q000379:methods*; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging*; D055815:Young Adult
keywords: Cobb method; Optimisation of X-ray imaging; exposure dose reduction; image quality preservation; lateral thoraco-lumbar imaging; superimposition method