Highlights
- •The delivered dose was unevenly distributed in the vicinity of a cardiac device.
- •Treatment planning systems were generally poor at estimating the pacemaker dose.
- •Skin dose exceeded pacemaker dose in head and neck treatments, but not in lung cases.
- •Simple square field reference data is useful even for more complex treatments.
Abstract
This study investigated the dose absorbed by tissues surrounding artificial cardiac
pacemakers during external beam radiotherapy procedures. The usefulness of out-of-field
reference data, treatment planning systems, and skin dose measurements to estimate
the dose in the vicinity of a pacemaker was also examined. Measurements were performed
by installing a pacemaker onto an anthropomorphic phantom, and using radiochromic
film and optically stimulated luminescence dosimeters to measure the dose in the vicinity
of the device during the delivery of square fields and clinical treatment plans. It
was found that the dose delivered in the vicinity of the cardiac device was unevenly
distributed both laterally and anteroposteriorly. As the device was moved distally
from the square field, the dose dropped exponentially, in line with out-of-field reference
data in the literature. Treatment planning systems were found to substantially underestimate
the dose for volumetric modulated arc therapy, helical tomotherapy, and 3D conformal
treatments. The skin dose was observed to be either greater or lesser than the dose
received at the depth of the device, depending on the treatment site, and so care
should be if skin dose measurements are to be used to estimate the dose to a pacemaker.
Square field reference data may be used as an upper estimate of absorbed dose per
monitor unit in the vicinity of a cardiac device for complex treatments involving
multiple gantry angles.
Keywords
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References
- The 11th world survey of cardiac pacing and implantable cardioverter-defibrillators: calendar year 2009–a World Society of Arrhythmia’s project.Pacing Clin Electrophysiol. 2011; 34: 1013-1027
- Radiotherapy to patients with artificial cardiac pacemakers.Cancer Treat Rev. 2005; 31: 474-486
- Radiotherapy in patients with cardiac pacemakers.Br J Radiol. 2014; 71: 4-10
- Treatment of patients with cardiac pacemakers and implantable cardioverter-defibrillators during radiotherapy.Int J Radiat Oncol Biol Phys. 2004; 59: 897-904
- Pacemaker failure induced by radiotherapy.Pacing Clin Electrophysiol. 1994; 17: 270-273
- Influence of high-energy photon beam irradiation on pacemaker operation.Phys Med Biol. 2002; 47: 2879-2893
- Radiotherapy in patients with pacemakers and implantable cardioverter defibrillators: a literature review.Europace. 2015;
- Management of radiation oncology patients with a pacemaker or ICD: a new comprehensive practical guideline in The Netherlands.Radiat Oncol. 2012; 7: 1-10
- Fetal dose from radiotherapy with photon beams: report of AAPM radiation therapy committee task group no. 36.Med Phys. 1995; 22: 63-82
- Peripheral dose from megavolt beams.Med Phys. 1983; 10: 809-818
- The accuracy of the out-of-field dose calculations using a model based algorithm in a commercial treatment planning system.Phys Med Biol. 2014; 59: N113-N128
- Accuracy of out-of-field dose calculation of tomotherapy and cyberknife treatment planning systems: a dosimetric study.Z Med Phys. 2014; 24: 211-215
- Accuracy of out-of-field dose calculations by a commercial treatment planning system.Phys Med Biol. 2010; 55: 6999-7008
- A comparison of out-of-field dose and its constituent components for intensity-modulated radiation therapy versus conformal radiation therapy: implications for carcinogenesis.Int J Radiat Oncol Biol Phys. 2011; 81: 1458-1464
- Establishing radiation therapy treatment planning effects involving implantable pacemakers and implantable cardioverter-defibrillators.J Appl Clin Med Phys. 2010; 11: 33-45
- Beam profile disturbances from implantable pacemakers or implantable cardioverter-defibrillator interactions.Med Dosim. 2011; 36: 358-364
- Measuring pacemaker dose: a clinical perspective.Med Dosim. 2012; 37: 170-174
- Estimating and reducing dose received by cardiac devices for patients undergoing radiotherapy.J Appl Clin Med Phys. 2015; 16: 411-422
- Dosimetric characterization and use of GAFCHROMIC EBT3 film for IMRT dose verification.J Appl Clin Med Phys. 2013; 14: 158-171
- Local heterogeneities in early batches of EBT2 film: a suggested solution.Phys Med Biol. 2010; 55: L37-L42
Gohlke C. tifffile.py: read and write image data from and to TIFF files; 2015. <https://pypi.python.org/pypi/tifffile>.
- Evaluation of a Gafchromic EBT2 film dosimetry system for radiotherapy quality assurance.Australas Phys Eng Sci Med. 2011; 34: 251-260
- Variations in photon energy spectra of a 6 MV beam and their impact on TLD response.Med Phys. 2011; 38: 2619-2628
- Technical note: calibrating radiochromic film in beams of uncertain quality.Med Phys. 2016; 43: 5647-5652
- The IPEMB code of practice for the determination of absorbed dose for X-rays below 300 kV generating potential (0.035 mm Al – 4 mm Cu HVL; 10–300 kV generating potential).Phys Med Biol. 1996; 41: 2605-2625
- Absorbed dose determination in external beam radiotherapy: an international code of practice for dosimetry based on standards of absorbed dose to water.in: IAEA technical reports series no. 398. IAEA, Vienna2000
- Dosimetric properties of improved GafChromic films for seven different digitizers.Med Phys. 2004; 31: 2392-2401
- A stable and efficient algorithm for nonlinear orthogonal distance regression.SIAM J Sci Comput. 1987; 8: 1052-1078
Jones E, Oliphant T, Peterson P. SciPy: open source scientific tools for Python; 2001. <http://www.scipy.org/>.
- Characterization of optically stimulated luminescent dosimeters, OSLDs, for clinical dosimetric measurements.Med Phys. 2007; 34: 4594-4604
- The energy dependence and dose response of a commercial optically stimulated luminescent detector for kilovoltage photon, megavoltage photon, and electron, proton, and carbon beams.Med Phys. 2009; 36: 1690-1699
- Angular dependence of the response of the nanoDot OSLD system for measurements at depth in clinical megavoltage beams.Med Phys. 2014; 41: 061712-1-061712-9
- A Monte Carlo model for calculating out-of-field dose from a Varian 6 MV beam.Med Phys. 2006; 33: 4405-4413
- Out-of-field dose measurements in a water phantom using different radiotherapy modalities.Phys Med Biol. 2012; 57: 5059-5074
- Accuracy and sources of error of out-of field dose calculations by a commercial treatment planning system for intensity-modulated radiation therapy treatments.J Appl Clin Med Phys. 2013; 14: 186-197
Article info
Publication history
Published online: November 21, 2016
Accepted:
November 7,
2016
Received in revised form:
November 3,
2016
Received:
June 16,
2016
Identification
Copyright
© 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
