Dosimetric Comparison of Manual and Beam Angle Optimization of Gantry Angles in IMRT

Journal Article · Sat Oct 01 00:00:00 EDT 2011 · Medical Dosimetry

DOI:https://doi.org/10.1016/j.meddos.2010.07.001· OSTI ID:21590487

Srivastava, Shiv P ^[1]; Kumar, Arvind ^[1]; Johnstone, Peter A.S. ^[2]

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1. Department of Radiation Oncology, Reid Hospital and Health Care Services, Richmond, IN (United States)
2. Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN (United States)

Dosimetric comparison of manual beam angle selection (MBS) and beam angle optimization (BAO) for IMRT plans is investigated retrospectively for 15 head and neck and prostate patients. The head and neck and prostate had planning target volumes (PTVs) ranging between 96.0 and 319.9 cm{sup 3} and 153.6 and 321.3 cm{sup 3}, whereas OAR ranged between 8.3 and 47.8 cm{sup 3} and 68.3 and 469.2 cm{sup 3}, respectively. In MBS, a standard coplanar 7-9 fields equally spaced gantry angles were used. In BAO, the selection of gantry angle was optimized by the algorithm for the same number of beams. The optimization and dose-volume constraints were kept the same for both techniques. Treatment planning was performed on the Eclipse treatment planning system. Our results showed that the dose-volume histogram for PTV are nearly identical in both techniques but BAO provided superior sparing of the organs at risk compared with the MBS. Also, MBS produced statistically significant higher monitor units (MU) and segments than the BAO; 13.1 {+-} 6.6% (p = 0.012) and 10.4 {+-} 13.6% (p = 0.140), and 14.6 {+-} 5.6% (p = 1.003E-5) and 12.6 {+-} 7.4% (p = 0.76E-3) for head and neck and prostate cases, respectively. The reduction in MU translates into the reduction in total body and integral dose. It is concluded that BAO provides advantage over MBS for most intenisty-modulated radiation therapy cases.

• OSTI ID: 21590487
• Journal Information: Medical Dosimetry, Vol. 36, Issue 3; Other Information: DOI: 10.1016/j.meddos.2010.07.001; PII: S0958-3947(10)00113-5; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0958-3947
• Country of Publication: United States
• Language: English

Related Subjects

61 RADIATION PROTECTION AND DOSIMETRY
ALGORITHMS
COMPARATIVE EVALUATIONS
DOSIMETRY
GEOMETRY
HAZARDS
INTEGRAL DOSES
NECK
OPTIMIZATION
PROSTATE
RADIOTHERAPY
BODY
DOSES
EVALUATION
GLANDS
MALE GENITALS
MATHEMATICAL LOGIC
MATHEMATICS
MEDICINE
NUCLEAR MEDICINE
ORGANS
RADIATION DOSES
RADIOLOGY
THERAPY