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Pediatric Radiology

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Open Access 01-08-2012 | Original Article

Dose optimisation for intraoperative cone-beam flat-detector CT in paediatric spinal surgery

Authors: Asger Greval Petersen, Søren Eiskjær, Jon Kaspersen

Published in: Pediatric Radiology | Issue 8/2012

Abstract

Background

During surgery for spinal deformities, accurate placement of pedicle screws may be guided by intraoperative cone-beam flat-detector CT.

Objective

The purpose of this study was to identify appropriate paediatric imaging protocols aiming to reduce the radiation dose in line with the ALARA principle.

Materials and methods

Using O-arm® (Medtronic, Inc.), three paediatric phantoms were employed to measure CTDI_w doses with default and lowered exposure settings. Images from 126 scans were evaluated by two spinal surgeons and scores were compared (Kappa statistics). Effective doses were calculated. The recommended new low-dose 3-D spine protocols were then used in 15 children.

Results

The lowest acceptable exposure as judged by image quality for intraoperative use was 70 kVp/40 mAs, 70 kVp/80 mAs and 80 kVp/40 mAs for the 1-, 5- and 12-year-old-equivalent phantoms respectively (kappa = 0,70). Optimised dose settings reduced CTDI_w doses 89–93%. The effective dose was 0.5 mSv (91–94,5% reduction). The optimised protocols were used clinically without problems.

Conclusions

Radiation doses for intraoperative 3-D CT using a cone-beam flat-detector scanner could be reduced at least 89% compared to manufacturer settings and still be used to safely navigate pedicle screws.

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Title: Dose optimisation for intraoperative cone-beam flat-detector CT in paediatric spinal surgery
Authors: Asger Greval Petersen
Søren Eiskjær
Jon Kaspersen
Publication date: 01-08-2012
Publisher: Springer-Verlag
Published in: Pediatric Radiology / Issue 8/2012
Print ISSN: 0301-0449
Electronic ISSN: 1432-1998
DOI: https://doi.org/10.1007/s00247-012-2396-0

Keynote webinar | Spotlight on sleep in brain health

Springer Medicine

Dose optimisation for intraoperative cone-beam flat-detector CT in paediatric spinal surgery

Abstract

Background

Objective

Materials and methods

Results

Conclusions

Keynote webinar | Spotlight on sleep in brain health

Springer Medicine

Abstract

Background

Objective

Materials and methods

Results

Conclusions

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