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
Affiliations: Prosthetics and Orthotics Department, The University
of Jordan, Amman, Jordan | Centre for Health Sciences Research, University of
Salford, Salford, UK | United National Institute for Prosthetics {\&}
Orthotics Development, University of Salford, Salford, UK | School of Computing, Science {\&} Engineering,
University of Salford, Salford, UK
Note: [] Corresponding author: Bashar Al Qaroot, Prosthetics and
Orthotics Department, The University of Jordan, Jordan. Tel.: +962 777 151 856;
E-mail: [email protected]
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. OBJECTIVES: 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. CONCLUSION: 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.
