RadOnc Smart Review

Welcome back to Radiation Oncology Smart Review – Episode 17 part B: Dosimetry Detectives and Chamber Charades. Last time, we tackled the ticking clocks of decay and permanent implants. Today, we put on our detective hats to investigate how we actually measure radiation and make sure the right dose goes to the right place. We’ll decode the secrets of ion chambers and their sneaky temperature-pressure dependence, master the Monitor Unit, or M U, calculations for both S A D and S S D setups – the absolute bedrock of clinical physics – figure out how dose changes with depth using P D Ds and T M Rs, and learn how linacs play geometric tricks with field sizes.

Welcome back to Radiation Oncology Smart Review – the targeted prep for your radiation oncology boards! I’m your guide, diving deep into the calculations that matter. This is Episode 17a of our Calculation Toolkit series, titled Radiation Oncology Calculations 1: Half-Lives and Seed Sleuths. Today we’ll master three bread-and-butter RAPHEX problem families: first, radioactive decay and time-activity puzzles, second, effective half-life mash-ups, and third, permanent implant total-dose questions. By the end you’ll know why lambda keeps physicists up at night, how to find the Goldilocks half-life combining body and physics, and how one sleepy iodine one twenty-five seed still manages to deliver its full punch over months.

Welcome back to the RadOnc Smart Review Physics Series for our concluding episode! In P16b, we explored the crucial planning modalities of CT and MRI. Today, in Episode P16c: PET & Ultrasound Physics for RadOnc, we round out our imaging tour by looking at two other important technologies: Positron Emission Tomography (PET), which gives us insights into metabolic function, and Ultrasound (US), often used for real-time guidance and visualizing certain structures.

Welcome back to the RadOnc Smart Review Physics Series! In P16a, we covered the crucial principles of radiation protection and the regulations governing our field. Now, in Episode P16b: CT & MRI Physics for RadOnc, we dive into the physics behind the two imaging modalities most fundamental to treatment planning: Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). How do they create the detailed anatomical images we rely on every day?

Welcome back to the RadOnc Smart Review Physics Series! We've explored how radiation is produced, how it interacts, how we measure it, plan treatments, and ensure quality. Now, we circle back to a fundamental responsibility: radiation safety. In Episode P16a: Radiation Protection & Regulations, we'll review the types of radiation effects, the quantities used to measure risk (Dose Equivalent, Effective Dose), the ALARA principle, the critical regulatory dose limits for workers and the public, and touch upon managing dose from internal radioactivity.

Welcome back to the RadOnc Smart Review Physics Series! In E15a, we covered brachytherapy sources and TG-43 dose calculations. In P15b, we looked at clinical applications and planning systems. Now, in our final brachytherapy episode, P15c: Brachytherapy QA, Safety & Regulations, we focus on arguably the most critical aspect: ensuring these procedures are performed safely and accurately, protecting both patients and staff, and complying with strict regulatory requirements.

Welcome back to the RadOnc Smart Review Physics Series! In P15a, we laid the groundwork for brachytherapy, focusing on the radioactive sources, how their strength is quantified using Air Kerma Strength (SK), and the details of the TG-43 dose calculation formalism. Now, in Episode P15b: Brachytherapy Applications, Systems & Planning Concepts, we'll explore how these sources are actually used clinically – looking at intracavitary vs interstitial techniques, historical planning systems, and specific dose points like ICRU 38's Points A and B.

Welcome back to the RadOnc Smart Review Physics Series! We've thoroughly covered external beam therapy. Now, we're shifting gears dramatically to explore treatments where the radiation source is placed inside or very close to the target. In Episode P15a: Brachytherapy Physics - Sources, Strength & Dose Calculation, we'll introduce the common radioactive isotopes used, discuss how their strength is properly quantified, and meticulously break down the fundamental TG-43 formalism used for calculating dose around these sources.

Welcome back to the RadOnc Smart Review Physics Series! In 14a, we explored the world of electron beams. Now, in Episode 14b: Proton Therapy Physics & Planning, we turn to the heavyweights: protons. Protons offer a unique dose deposition pattern, the Bragg peak, which allows for potentially superior sparing of normal tissues distal to the target. We'll delve into the physics behind proton interactions, how clinical beams are created, the critical challenge of range uncertainty, and specific planning considerations.

Welcome back to the RadOnc Smart Review Physics Series! After exploring advanced photon techniques like IMRT, VMAT, and SRS/SBRT, we're now switching particle types. In Episode P14a: Electron Beam Physics & Planning, we focus entirely on the clinical workhorse for treating shallow targets: the electron beam. We'll examine its unique depth dose characteristics, how its shape changes with depth, planning considerations, and clinical uses.