Radiation Oncology/Physics/AAPM
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American Association of Physicists in Medicine (AAPM)
AAPM Reports
[edit | edit source]Task Groups:
- TG 34 (PDF) - "Management of Radiation Oncology Patients with Implanted Cardiac Pacemakers" (Reprinted from Medical Physics, Vol. 21, Issue 1) (1994)
- TG 36 (PDF) - Fetal Dose from Radiotherapy with Photon Beams
- TG 40 (PDF) - Comprehensive QA for Radiation Oncology
- TG 43 (PDF) - Dosimetry of Interstitial Brachytherapy Sources (1995)
- TG 60 - Intravascular Brachytherapy Physics
- TG 63 (PDF) - Dosimetric considerations for patients with HIP prostheses undergoing pelvic irradiation
- TG 65 (AAPM 85) - Tissue Inhomogeneity Corrections (PDF, 2004)
TG 43 (Dosimetry of Interstitial Brachytherapy Sources)
- Introduction: New formalism needed due to significant variance in exposure rate constants, and due to difficulty of accurately calculating 2D dose distribution in tissue due to significant anisotropy of actual cylindrical brachytherapy sources
- Description of sources: Iridium-192, Iodine-125, Palladium-103
- Recommended dose calculation formalism:
- Historically: Dose rate = A * f * Γ * 1/r2 * T(r) * Φ
- New: Dose rate = Sk * Λ * G(r,θ)/G(r0,θ0) * g(r) * F(r,θ)
- Sk: air kerma strength, usually specified at 1 m, unit defined by U (μGy m2 h-1
- Λ: dose rate constant, defined as dose rate to water at a distance 1 cm on the transverse axis
- G(r,θ): geometry factor, accounts for variation of relative dose due only to spatial distribution of activity within the source, ignoring photon absorption and scattering
- g(r): radial dose function, accounts for effects of absorption and scatter in the medium along the transverse axis of the source
- F(r,θ): anisotropy function, accounts for anisotropy of dose distribution around the source, including the effects of absorption and scatter in the medium
- Reference point (r0, θ0): lies on transverse bisector of the source, at a distance of 1 cm from its center
- Recommended dosimetry parameters provided for I-125, Ir-192, and Pd-103