title: Assessment of wear and periacetabular osteolysis using dual energy computed tomography on a pig cadaver to identify the lowest acceptable radiation dose.
abstract: OBJECTIVE
  Computed tomography (CT) plays an important role in evaluating wear and periacetabular osteolysis (PAO) in total hip replacements. One concern with CT is the high radiation exposure since standard pelvic CT provides approximately 3.5 millisieverts (mSv) of radiation exposure, whereas a planar radiographic examination with three projections totals approximately 0.5 mSv. The objective of this study was to evaluate the lowest acceptable radiation dose for dual-energy CT (DECT) images when measuring wear and periacetabular osteolysis in uncemented metal components.
  
  
  METHODS
  A porcine pelvis with bilateral uncemented hip prostheses and with known linear wear and acetabular bone defects was examined in a third-generation multidetector DECT scanner. The examinations were performed with four different radiation levels both with and without iterative reconstruction techniques. From the high and low peak kilo voltage acquisitions, polychrmoatic images were created together with virtual monochromatic images of energies 100 kiloelectron volts (keV) and 150 keV.
  
  
  RESULTS
  We could assess wear and PAO while substantially lowering the effective radiation dose to 0.7 mSv for a total pelvic view with an accuracy of around 0.5 mm for linear wear and 2 mm to 3 mm for PAO.
  
  
  CONCLUSIONS
  CT for detection of prosthetic wear and PAO could be used with clinically acceptable accuracy at a radiation exposure level equal to plain radiographic exposures.Cite this article: B. Sandgren, M. Skorpil, P. Nowik, H. Olivecrona, J. Crafoord, L. Weidenhielm, A. Persson. Assessment of wear and periacetabular osteolysis using dual energy computed tomography on a pig cadaver to identify the lowest acceptable radiation dose. Bone Joint Res 2016;5:307-313. DOI: 10.1302/2046-3758.57.2000566.
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden bustersandgren@hotmail.com.
authors.forename: B
authors.initials: B
authors.lastname: Sandgren
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Skorpil
authors.affiliation: Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Nowik
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Olivecrona
authors.affiliation: Department of Radiology, Ersta Hospital, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Crafoord
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Weidenhielm
authors.affiliation: Center for Medical Image Science and Visualization, Linköping University, Hêlsouniversitetet, Linköping, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Persson
keywords: Accuracy; Low-dose dual-energy computed tomography; Osteolysis; Wear