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A CT method for following patients with both prosthetic replacement and implanted tantalum beads: preliminary analysis with a pelvic model and in seven patients.

Olivecrona, Henrik; Maguire, Gerald Q; Noz, Marilyn E; Zeleznik, Michael P; Kesteris, Uldis LU and Weidenhielm, Lars (2016) In Journal of Orthopaedic Surgery and Research 11(1).
Abstract
BACKGROUND:



Radiostereometric analysis (RSA) is often used for evaluating implanted devices over time. Following patients who have had tantalum beads implanted as markers in conjunction with joint replacements is important for longitudinal evaluation of these patients and for those with similar implants. As doing traditional RSA imaging is exacting and limited to specialized centers, it is important to consider alternative techniques for this ongoing evaluation. This paper studies the use of computed tomography (CT) to evaluate over time tantalum beads which have been implanted as markers.

METHODS:



The project uses both a hip model implanted with tantalum beads, acquired in several... (More)
BACKGROUND:



Radiostereometric analysis (RSA) is often used for evaluating implanted devices over time. Following patients who have had tantalum beads implanted as markers in conjunction with joint replacements is important for longitudinal evaluation of these patients and for those with similar implants. As doing traditional RSA imaging is exacting and limited to specialized centers, it is important to consider alternative techniques for this ongoing evaluation. This paper studies the use of computed tomography (CT) to evaluate over time tantalum beads which have been implanted as markers.

METHODS:



The project uses both a hip model implanted with tantalum beads, acquired in several orientations, at two different CT energy levels, and a cohort of seven patients. The model was evaluated twice by the same observer with a 1-week interval. All CT volumes were analyzed using a semi-automated 3D volume fusion (spatial registration) tool which provides landmark-based fusion of two volumes, registering a target volume with a reference volume using a rigid body 3D algorithm. The mean registration errors as well as the accuracy and repeatability of the method were evaluated.

RESULTS:



The mean registration error, maximum value of repeatability, and accuracy for the relative movement in the model were 0.16 mm, 0.02° and 0.1 mm, and 0.36° and 0.13 mm for 120 kVp and 0.21 mm, 0.04° and 0.01 mm, and 0.39° and 0.12 mm for 100 kVp. For the patients, the mean registration errors per patient ranged from 0.08 to 0.35 mm. These results are comparable to those in typical clinical RSA trials. This technique successfully evaluated two patients who would have been lost from the cohort if only RSA were used.

CONCLUSIONS:



The proposed technique can be used to evaluate patients with tantalum beads over time without the need for stereoradiographs. Further, the effective dose associated with CT is decreasing. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Orthopaedic Surgery and Research
volume
11
issue
1
publisher
BioMed Central
external identifiers
  • pmid:26911571
  • scopus:84959129104
  • wos:000370777100001
ISSN
1749-799X
DOI
10.1186/s13018-016-0360-7
language
English
LU publication?
yes
id
87119ad7-0aa5-4a7d-9146-309dd18c3c64 (old id 8821749)
alternative location
http://www.ncbi.nlm.nih.gov/pubmed/26911571?dopt=Abstract
date added to LUP
2016-03-02 14:35:16
date last changed
2017-02-26 03:57:32
@article{87119ad7-0aa5-4a7d-9146-309dd18c3c64,
  abstract     = {BACKGROUND:<br/><br>
<br/><br>
Radiostereometric analysis (RSA) is often used for evaluating implanted devices over time. Following patients who have had tantalum beads implanted as markers in conjunction with joint replacements is important for longitudinal evaluation of these patients and for those with similar implants. As doing traditional RSA imaging is exacting and limited to specialized centers, it is important to consider alternative techniques for this ongoing evaluation. This paper studies the use of computed tomography (CT) to evaluate over time tantalum beads which have been implanted as markers.<br/><br>
METHODS:<br/><br>
<br/><br>
The project uses both a hip model implanted with tantalum beads, acquired in several orientations, at two different CT energy levels, and a cohort of seven patients. The model was evaluated twice by the same observer with a 1-week interval. All CT volumes were analyzed using a semi-automated 3D volume fusion (spatial registration) tool which provides landmark-based fusion of two volumes, registering a target volume with a reference volume using a rigid body 3D algorithm. The mean registration errors as well as the accuracy and repeatability of the method were evaluated.<br/><br>
RESULTS:<br/><br>
<br/><br>
The mean registration error, maximum value of repeatability, and accuracy for the relative movement in the model were 0.16 mm, 0.02° and 0.1 mm, and 0.36° and 0.13 mm for 120 kVp and 0.21 mm, 0.04° and 0.01 mm, and 0.39° and 0.12 mm for 100 kVp. For the patients, the mean registration errors per patient ranged from 0.08 to 0.35 mm. These results are comparable to those in typical clinical RSA trials. This technique successfully evaluated two patients who would have been lost from the cohort if only RSA were used.<br/><br>
CONCLUSIONS:<br/><br>
<br/><br>
The proposed technique can be used to evaluate patients with tantalum beads over time without the need for stereoradiographs. Further, the effective dose associated with CT is decreasing.},
  articleno    = {27},
  author       = {Olivecrona, Henrik and Maguire, Gerald Q and Noz, Marilyn E and Zeleznik, Michael P and Kesteris, Uldis and Weidenhielm, Lars},
  issn         = {1749-799X},
  language     = {eng},
  number       = {1},
  publisher    = {BioMed Central},
  series       = {Journal of Orthopaedic Surgery and Research},
  title        = {A CT method for following patients with both prosthetic replacement and implanted tantalum beads: preliminary analysis with a pelvic model and in seven patients.},
  url          = {http://dx.doi.org/10.1186/s13018-016-0360-7},
  volume       = {11},
  year         = {2016},
}