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Performance and suitability assessment of a real-time 3D electromagnetic needle tracking system for interstitial brachytherapy.

Boutaleb S, Racine E, Fillion O, Bonillas A, Hautvast G, Binnekamp D, Beaulieu L - J Contemp Brachytherapy (2015)

Bottom Line: Position errors of less than 1 mm were recorded with all components except with a metallic arm support, which induced a mean absolute error of approximately 1.4 mm when located 10 cm away from the needle sensor.The Aurora(®) V1 PFG EMTS possesses a great potential for real-time treatment assistance in general interstitial brachytherapy.In view of our experimental results, we however recommend that the needle axis remains as parallel as possible to the generator surface during treatment and that the tracking zone be restricted to the first 30 cm from the generator surface.

View Article: PubMed Central - PubMed

Affiliation: Département de Radio-Oncologie et Centre de Recherche du CHU de Québec, Québec, Canada ; Département de Physique, de Génie Physique et d'Optique et Centre de Recherche sur le Cancer, Université Laval, Québec, Canada.

ABSTRACT

Purpose: Accurate insertion and overall needle positioning are key requirements for effective brachytherapy treatments. This work aims at demonstrating the accuracy performance and the suitability of the Aurora(®) V1 Planar Field Generator (PFG) electromagnetic tracking system (EMTS) for real-time treatment assistance in interstitial brachytherapy procedures.

Material and methods: The system's performance was characterized in two distinct studies. First, in an environment free of EM disturbance, the boundaries of the detection volume of the EMTS were characterized and a tracking error analysis was performed. Secondly, a distortion analysis was conducted as a means of assessing the tracking accuracy performance of the system in the presence of potential EM disturbance generated by the proximity of standard brachytherapy components.

Results: The tracking accuracy experiments showed that positional errors were typically 2 ± 1 mm in a zone restricted to the first 30 cm of the detection volume. However, at the edges of the detection volume, sensor position errors of up to 16 mm were recorded. On the other hand, orientation errors remained low at ± 2° for most of the measurements. The EM distortion analysis showed that the presence of typical brachytherapy components in vicinity of the EMTS had little influence on tracking accuracy. Position errors of less than 1 mm were recorded with all components except with a metallic arm support, which induced a mean absolute error of approximately 1.4 mm when located 10 cm away from the needle sensor.

Conclusions: The Aurora(®) V1 PFG EMTS possesses a great potential for real-time treatment assistance in general interstitial brachytherapy. In view of our experimental results, we however recommend that the needle axis remains as parallel as possible to the generator surface during treatment and that the tracking zone be restricted to the first 30 cm from the generator surface.

No MeSH data available.


Related in: MedlinePlus

Experimental setup used for tracking accuracy analysis and characterization of the boundaries of the detection volume. The system z axis is perpendicular to the surface of the field generator
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Figure 0002: Experimental setup used for tracking accuracy analysis and characterization of the boundaries of the detection volume. The system z axis is perpendicular to the surface of the field generator

Mentions: Tracking accuracy analysis and characterization of the boundaries of the detection volume were conducted in an environment free of EM disturbance. The setup used for these experiments is shown in Figure 2. A specially designed mobile needle support was mounted on an optical table, along with a fixed support to maintain the field generator. The needle was solidly maintained on a parallel plastic plate that could be moved vertically by a precise toothed wheel mechanism. At any time, the needle and the field generator were located at least 30 cm above the optical table. The surface of the optical table used is made of stainless steel, which is one of the most likely material to generate EM distortion. Northern Digital Inc., however, specifies that the EMTS can be operated above such a surface provided that the field generator and tracked sensors remain at a distance of at least 30 cm from the latter. This unique setup dampens potential vibrations while providing submillimetric displacement capabilities (± 0.25 mm).


Performance and suitability assessment of a real-time 3D electromagnetic needle tracking system for interstitial brachytherapy.

Boutaleb S, Racine E, Fillion O, Bonillas A, Hautvast G, Binnekamp D, Beaulieu L - J Contemp Brachytherapy (2015)

Experimental setup used for tracking accuracy analysis and characterization of the boundaries of the detection volume. The system z axis is perpendicular to the surface of the field generator
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4643737&req=5

Figure 0002: Experimental setup used for tracking accuracy analysis and characterization of the boundaries of the detection volume. The system z axis is perpendicular to the surface of the field generator
Mentions: Tracking accuracy analysis and characterization of the boundaries of the detection volume were conducted in an environment free of EM disturbance. The setup used for these experiments is shown in Figure 2. A specially designed mobile needle support was mounted on an optical table, along with a fixed support to maintain the field generator. The needle was solidly maintained on a parallel plastic plate that could be moved vertically by a precise toothed wheel mechanism. At any time, the needle and the field generator were located at least 30 cm above the optical table. The surface of the optical table used is made of stainless steel, which is one of the most likely material to generate EM distortion. Northern Digital Inc., however, specifies that the EMTS can be operated above such a surface provided that the field generator and tracked sensors remain at a distance of at least 30 cm from the latter. This unique setup dampens potential vibrations while providing submillimetric displacement capabilities (± 0.25 mm).

Bottom Line: Position errors of less than 1 mm were recorded with all components except with a metallic arm support, which induced a mean absolute error of approximately 1.4 mm when located 10 cm away from the needle sensor.The Aurora(®) V1 PFG EMTS possesses a great potential for real-time treatment assistance in general interstitial brachytherapy.In view of our experimental results, we however recommend that the needle axis remains as parallel as possible to the generator surface during treatment and that the tracking zone be restricted to the first 30 cm from the generator surface.

View Article: PubMed Central - PubMed

Affiliation: Département de Radio-Oncologie et Centre de Recherche du CHU de Québec, Québec, Canada ; Département de Physique, de Génie Physique et d'Optique et Centre de Recherche sur le Cancer, Université Laval, Québec, Canada.

ABSTRACT

Purpose: Accurate insertion and overall needle positioning are key requirements for effective brachytherapy treatments. This work aims at demonstrating the accuracy performance and the suitability of the Aurora(®) V1 Planar Field Generator (PFG) electromagnetic tracking system (EMTS) for real-time treatment assistance in interstitial brachytherapy procedures.

Material and methods: The system's performance was characterized in two distinct studies. First, in an environment free of EM disturbance, the boundaries of the detection volume of the EMTS were characterized and a tracking error analysis was performed. Secondly, a distortion analysis was conducted as a means of assessing the tracking accuracy performance of the system in the presence of potential EM disturbance generated by the proximity of standard brachytherapy components.

Results: The tracking accuracy experiments showed that positional errors were typically 2 ± 1 mm in a zone restricted to the first 30 cm of the detection volume. However, at the edges of the detection volume, sensor position errors of up to 16 mm were recorded. On the other hand, orientation errors remained low at ± 2° for most of the measurements. The EM distortion analysis showed that the presence of typical brachytherapy components in vicinity of the EMTS had little influence on tracking accuracy. Position errors of less than 1 mm were recorded with all components except with a metallic arm support, which induced a mean absolute error of approximately 1.4 mm when located 10 cm away from the needle sensor.

Conclusions: The Aurora(®) V1 PFG EMTS possesses a great potential for real-time treatment assistance in general interstitial brachytherapy. In view of our experimental results, we however recommend that the needle axis remains as parallel as possible to the generator surface during treatment and that the tracking zone be restricted to the first 30 cm from the generator surface.

No MeSH data available.


Related in: MedlinePlus