Evaluation of radiotherapy setup accuracy for head and neck cancer using a 3-D surface imaging system

Cho, H L; Park, E T; Kim, J Y; Kwak, K S; Kim, C J; Ahn, Ki-Jung; Suh, Tae-Suk; Lee, Y K; Kim, S W; Kim, J K; Lim, Sangwook; Choi, Youngmin; Park, S K

doi:10.1088/1748-0221/8/11/t11002

Cited by 9 publications

(10 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, as the accuracy of SGRT systems varies as a function of couch rotations, additional QA may be necessary for treatment that include couch rotations (see Section 4.6.2). In head and neck cancer patients, weight loss, variability in shoulder immobilization, and deflection of the treatment couch can cause deformations that reduce the accuracy of SGRT registration algorithms, 27 especially in the neck 54–56 . As such, the treatment team should be prepared to identify the cause and troubleshoot the resultant effects on SGRT accuracy.…”

Section: Current Clinical Applications With Workflow Recommendationsmentioning

confidence: 99%

AAPM task group report 302: Surface‐guided radiotherapy

et al. 2022

View full text Add to dashboard Cite

The clinical use of surface imaging has increased dramatically, with demonstrated utility for initial patient positioning, real-time motion monitoring, and beam gating in a variety of anatomical sites. The Therapy Physics Subcommittee and the Imaging for Treatment Verification Working Group of the American Association of Physicists in Medicine commissioned Task Group 302 to review the current clinical uses of surface imaging and emerging clinical applications. The specific charge of this task group was to provide technical guidelines for clinical indications of use for general positioning, breast deep-inspiration breath hold treatment, and frameless stereotactic radiosurgery. Additionally, the task group was charged with providing commissioning and on-going quality assurance (QA) requirements for surface-guided radiation therapy (SGRT) as part of a comprehensive QA program including risk assessment. Workflow considerations for other anatomic sites and for computed tomography simulation, including motion management, are also discussed. Finally, developing clinical applications, such as stereotactic body radiotherapy (SBRT) or proton radiotherapy, are presented. The recommendations made in this report, which are summarized at the end of the report, are applicable to all video-based SGRT systems available at the time of writing.

show abstract

Section: Current Clinical Applications With Workflow Recommendationsmentioning

confidence: 99%

AAPM task group report 302: Surface‐guided radiotherapy

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Optical surface guidance has been used for patient positioning and monitoring for a range of clinical sites, [9][10][11][12] including intracranial SRS. 4,13 Detailed descriptions of this technology have been previously published 14 and only a basic overview is presented here.…”

Section: Introductionmentioning

confidence: 99%

Optical surface guidance for submillimeter monitoring of patient position during frameless stereotactic radiotherapy

Covington

Fiveash

et al. 2019

J Applied Clin Med Phys

View full text Add to dashboard Cite

Purpose To evaluate the accuracy of monitoring intrafraction motion during stereotactic radiotherapy with the optical surface monitoring system. Prior studies showing a false increase in the magnitude of translational offsets at non‐coplanar couch positions prompted the vendor to implement software changes. This study evaluated two software improvements intended to address false offsets. Methods The vendor implemented two software improvements: a volumetric (ACO) rather than planar calibration and, approximately 6 months later, an improved calibration workflow (CIB) designed to better compensate for thermal drift. Offsets relative to the reference position, obtained at table angle 0 following image‐guided setup, were recorded before beam‐on at each table position and at the end of treatment the table returned to 0° for patients receiving SRT. Results Prior to ACO, between ACO and CIB, and after CIB, 223, 155, and 436 fractions were observed respectively. The median magnitude of translational offsets at the end of treatment was similar for all three intervals: 0.29, 0.33, and 0.27 mm. Prior to ACO, the offset magnitude for non‐zero table positions had a median of 0.79 mm and was found to increase with increasing distance from isocenter to the anterior patient surface. After ACO, the median magnitude was 0.74 mm, but the dependence on surface‐to‐isocenter distance was eliminated. After CIB, the median magnitude for non‐zero table positions was reduced to 0.57 mm. Conclusion Ongoing improvements in software and calibration procedures have decreased reporting of false offsets at non‐zero table angles. However, the median magnitude for non‐zero table angles is larger than that observed at the end of treatment, indicating that accuracy remains better when the table is not rotated.

show abstract

“…Recently, with the technological advancements in optical reconstruction and projection techniques, surface imaging has become increasingly more popular as a non-invasive, non-radiographic form of image guidance. Surface imaging (SI) systems use a combination of real-time optical and laser-based imaging techniques that have been shown to properly position patients, 1,2 accurately monitor, and quantify movement throughout the entirety of treatment, 3,4 and provide an accurate and reproducible respiratory surrogate for gatingbased deliveries. [5][6][7][8][9][10] The ability of SI systems to non-radiographically collect a live surface image, determine positional correction vectors needed to match image to a predefined reference image, and monitor sub-millimeter movements have made it a successful component of SRT where small targets and small margins are ever-present important considerations.…”

mentioning

confidence: 99%

Surface guided imaging during stereotactic radiosurgery with automated delivery

Covington

Stanley

Fiveash

et al. 2020

J Applied Clin Med Phys

View full text Add to dashboard Cite

Purpose: To report on the use of surface guided imaging during frameless intracranial stereotactic radiotherapy with automated delivery via HyperArc TM (Varian Medical Systems, Palo Alto, CA). Methods: All patients received intracranial radiotherapy with HyperArc TM and were monitored for intrafraction motion by the AlignRT® (VisionRT, London, UK) surface imaging (SI) system. Immobilization was with the Encompass TM (Qfix, Avondale, PA) aquaplast mask device. AlignRT® log files were correlated with trajectory log files to correlate treatment parameters with SI reported offsets. SI reported offsets were correlated with gantry angle and analyzed for performance issues at non-zero couch angles and during camera-pod blockage during gantry motion. Demographics in the treatment management system were used to identify race and determine if differences in SI reported offsets are due to skin tone settings. Results: A total of 981 fractions were monitored over 14 months and 819 were analyzed. The median AlignRT® reported motion from beginning to the end of treatment was 0.24 mm. The median offset before beam on at non-zero couch angles was 0.55 mm. During gantry motion when camera pods are blocked, the median magnitude was below 1 mm. Median magnitude of offsets at non-zero couch angles was not found to be significantly different for patients stratified by race. Conclusions: Surface image guidance is a viable alternative to scheduled mid-treatment imaging for monitoring intrafraction motion during stereotactic radiosurgery with automated delivery.

show abstract

Evaluation of radiotherapy setup accuracy for head and neck cancer using a 3-D surface imaging system

Cited by 9 publications

References 23 publications

AAPM task group report 302: Surface‐guided radiotherapy

AAPM task group report 302: Surface‐guided radiotherapy

Optical surface guidance for submillimeter monitoring of patient position during frameless stereotactic radiotherapy

Surface guided imaging during stereotactic radiosurgery with automated delivery

Contact Info

Product

Resources

About