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Review of advanced catheter technologies in radiation oncology brachytherapy procedures.

Zhou J, Zamdborg L, Sebastian E - Cancer Manag Res (2015)

Bottom Line: The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy.Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed.New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, USA ; Oakland University William Beaumont School of Medicine, Royal Oak, MI, USA.

ABSTRACT
The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented.

No MeSH data available.


Related in: MedlinePlus

Prostate (yellow contour), uretheral (green contour), catheters (white dots in the axial image), and their reconstructions (blue circles and catheters) shown in a TRUS image-based prostate high dose rate planning system. The coronal, axial, and sagittal views of the TRUS image are shown in the left upper, left lower, and right lower panes, respectively.Abbreviation: TRUS, transrectal ultrasound.
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f1-cmar-7-199: Prostate (yellow contour), uretheral (green contour), catheters (white dots in the axial image), and their reconstructions (blue circles and catheters) shown in a TRUS image-based prostate high dose rate planning system. The coronal, axial, and sagittal views of the TRUS image are shown in the left upper, left lower, and right lower panes, respectively.Abbreviation: TRUS, transrectal ultrasound.

Mentions: In brachytherapy, catheter reconstruction is one of the most important procedures in treatment planning, and relates the source tracks and dwell positions to the patient’s anatomy (eg, targets and organs at risk). As discussed previously, investigators have tried to improve the fidelity of detectability and visualization of catheters and applicators on imaging. However, due to the intrinsic limitations of some imaging modalities, it is difficult to accurately reconstruct catheters. For example, in a TRUS-based real time prostate HDR implant procedure, a treatment plan is generated in real time and the treatment is delivered while the patient is still in the same position. As the dosimetry of a treatment plan is directly related to needle positions, accurate catheter reconstruction is critical for accurate dosimetry. However, as shown in Figure 1, this is highly challenging, due to degraded ultrasound images from tissue speckles, calcifications, and in some cases, radiopaque markers. In addition, interference between catheters, due to signal reflection and interchannel crosstalk, further deteriorates catheter identification and thus reconstruction. As image resolution decreases with increasing distance from the probe, the catheter localization accuracy in the anterior part of the image is further decreased. Studies have shown that ultrasound beam width artifacts, an obscured needle tip, and a slightly bent ultrasound probe can result in greater than 5 mm errors in catheter tip localization.76–78 When a catheter is shadowed by another catheter posteriorly, or is close to strongly reflecting objects, its reconstruction can be very unreliable. Wilkinson and Kolar recently investigated medical event reports on the Nuclear Regulatory Commission website for HDR-related events for the years 1999–2012.79 Of all 44 events reported, 29 were related to catheter reconstruction, including wrong index length, wrong catheter track identification, and misidentification of first dwell position.


Review of advanced catheter technologies in radiation oncology brachytherapy procedures.

Zhou J, Zamdborg L, Sebastian E - Cancer Manag Res (2015)

Prostate (yellow contour), uretheral (green contour), catheters (white dots in the axial image), and their reconstructions (blue circles and catheters) shown in a TRUS image-based prostate high dose rate planning system. The coronal, axial, and sagittal views of the TRUS image are shown in the left upper, left lower, and right lower panes, respectively.Abbreviation: TRUS, transrectal ultrasound.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507789&req=5

f1-cmar-7-199: Prostate (yellow contour), uretheral (green contour), catheters (white dots in the axial image), and their reconstructions (blue circles and catheters) shown in a TRUS image-based prostate high dose rate planning system. The coronal, axial, and sagittal views of the TRUS image are shown in the left upper, left lower, and right lower panes, respectively.Abbreviation: TRUS, transrectal ultrasound.
Mentions: In brachytherapy, catheter reconstruction is one of the most important procedures in treatment planning, and relates the source tracks and dwell positions to the patient’s anatomy (eg, targets and organs at risk). As discussed previously, investigators have tried to improve the fidelity of detectability and visualization of catheters and applicators on imaging. However, due to the intrinsic limitations of some imaging modalities, it is difficult to accurately reconstruct catheters. For example, in a TRUS-based real time prostate HDR implant procedure, a treatment plan is generated in real time and the treatment is delivered while the patient is still in the same position. As the dosimetry of a treatment plan is directly related to needle positions, accurate catheter reconstruction is critical for accurate dosimetry. However, as shown in Figure 1, this is highly challenging, due to degraded ultrasound images from tissue speckles, calcifications, and in some cases, radiopaque markers. In addition, interference between catheters, due to signal reflection and interchannel crosstalk, further deteriorates catheter identification and thus reconstruction. As image resolution decreases with increasing distance from the probe, the catheter localization accuracy in the anterior part of the image is further decreased. Studies have shown that ultrasound beam width artifacts, an obscured needle tip, and a slightly bent ultrasound probe can result in greater than 5 mm errors in catheter tip localization.76–78 When a catheter is shadowed by another catheter posteriorly, or is close to strongly reflecting objects, its reconstruction can be very unreliable. Wilkinson and Kolar recently investigated medical event reports on the Nuclear Regulatory Commission website for HDR-related events for the years 1999–2012.79 Of all 44 events reported, 29 were related to catheter reconstruction, including wrong index length, wrong catheter track identification, and misidentification of first dwell position.

Bottom Line: The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy.Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed.New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Beaumont Health System, Royal Oak, MI, USA ; Oakland University William Beaumont School of Medicine, Royal Oak, MI, USA.

ABSTRACT
The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented.

No MeSH data available.


Related in: MedlinePlus