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Familiarize myself with PET/CT
- Discuss the basics of PET, CT and PET/CT scanners
- Discuss the purpose of PET/CT in oncology
- Address limitations
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Observe the clinical use of PET/CT
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Conduct an experiment for measuring the resolution in a PET scanner
- Build a phantom for measuring the resolution of hot sources on a cold background
- Use 18F-FDG to measure the resolution of the GE Advance Pet Scanner in the department
C. Evaluation of Achievement:
1. Prospective Statement (Provided at the date SDEP initiated):
Upon completion of the project, a PowerPoint lecture will be created for radiation oncology residents on CT/PET use in radiation oncology. The lecture will be delivered to the residents in the department and their evaluation will be compiled to assess the success of the project.
2. Final Statement (Provided at the date SDEP completed):
The project has resulted in creation of an educational lecture on PET/CT. A slide presentation is available for use by members of the department. Specific learning objectives have been documented. Evaluation by the residents following the presentation showed a favorable response regarding fulfillment of the learning objectives and furthering their understanding of PET/CT technology and its clinical utility.
D. Impact on Practice/Outcome Statement:
1. Prospective Statement (Provided at the date SDEP initiated):
Medical imaging is an essential tool in radiation therapy. Computed tomography (CT) and positron emission tomography (PET) are image modalities that have been used in diagnosis and staging of diseases and in monitoring the effects of therapy. The high-resolution anatomical imaging ability of CT and the accurate localization of functional abnormalities with PET provide valuable information for patient management. The biological information from a PET/CT image can aid oncologists in assessing tumor hypoxia and potential doubling time.
2. Final Statement (Provided at the date SDEP is completed):
The implementation of the SDEP on CT/PET has benefited the institution in achieving a full understanding of the consequences of implementing the modality. It has aided in the understanding of the advantages of multimodality imaging application in radiation oncology. It provides detailed step-by-step process implementation tools.
SDEP Example 2 : Therapeutic Radiologic Physics
Title: HDR Treatments and Treatment Planning
Category: Education
Date Initiated:
Date Completed:
A. Significance:
High-dose-rate brachytherapy (20 cGy/min and higher) is used for the treatment of cancer in radiotherapy clinics nationwide. Since the advent of the remote after loader, HDR has gained popularity over LDR because it is an outpatient procedure requiring a much abbreviated hospital stay as compared to LDR. As a medical physicist, a comprehensive understanding of this treatment modality is absolutely essential. Although I am a board-certified medical dosimetrist, I have little to no experience with brachytherapy; therefore, I see this as my biggest weakness in my development as a clinical medical physicist. The goals of this project are to obtain a working knowledge of the Nucletron system and PLATO planning software, as well as to familiarize myself with the delivery process and required QA and safety checks.
B. Approach:
In order to really familiarize myself with Nucletron’s PLATO planning system, it will be necessary to run a large number of treatment plans, as one plan will not be enough to gain any sort of proficiency with the system. I will concentrate my efforts on tandem and ovoid treatments, but will venture into breast treatments if possible. For the tandem and ovoid cases, I will acquire films of patients who have been treated in the past and attempt to recreate their original plans. I can check my accuracy by comparing my plan to the actual treatment. I will attempt to follow a similar procedure for the breast patients, but will use CT scans of previously treated patients.
The second component of this project is to learn about the actual procedure. I have chosen to follow one breast patient from the beginning of simulation to the end of the first treatment. I will begin by observing the placement of the catheters; I will then watch the medical physicist run the treatment plan and attend the first treatment. At the time of treatment, I hope to get some hands-on experience by running the Nucletron consul, performing the relevant paperwork, and physically attaching transfer tubes under the direct supervision of a certified medical physicist.
I intend to compliment the above project with outside research on the topic to increase my understanding of HDR brachytherapy practice and procedures.
C. Evaluation of Achievement:
1. Prospective Statement (Provided at the date SDEP is initiated):
Upon completion of the project, a report will be presented summarizing all procedures observed and completed. All printouts of plans run can be printed if necessary. One example will be included as part of the report. The workup will include a critical comparison of the methods, detailing assumptions made in each and outlining various aspects and considerations per discussion points raised in the literature as well as personal observations. A final analysis of the plans will be made with an experienced physicist/dosimetrist and radiation oncologist.
2. Final Statement (Provided at the date SDEP is completed):
The summary report prepared has documented the above activities related to the HDR treatment planning, date of its completion, and data for all relevant findings. Specific steps of the processes related to planning and delivery as well as their verification are identified.
D. Impact on Practice/Outcome Statement
1. Prospective Statement (Provided at the date SDEP is initiated):
At the completion of this SDEP, I will have the benefit of acquiring HDR planning and delivery skill. It will allow me to offer additional physics support to my institution and broaden the scope of my expertise. However, the documentation and record keeping required for the various options must be fully understood and evaluated as to realities of implementation and efficacy. to confirm the protocol most appropriate for use.
2. Final Statement (Provided at the date SDEP is completed):
As a result of completing this self-directed project, I achieved my original goal of gaining a working knowledge of HDR. Going into the project, I had little to no knowledge of what was involved with HDR treatment. After completing all of the above procedures, I have a much better understanding of this treatment technique and will have less to learn when I encounter it again later in my career.
SDEP Example 3: Therapeutic Radiologic Physics
Title/Significance
Title: Using the TG-51 Protocol for Calibration Dosimetry
Category: Clinical Practice
Date Initiated:
Date Completed:
A. Significance:
During the last decade, radiation therapy high energy accelerator beams have been calibrated following the TG21 recommended protocol. AAPM’s TG-51 protocol for clinical reference dosimetry of high-energy photon and electron beams is an improved and significantly revised protocol. It is strongly recommended by the Radiologic Physics Center and the Therapy Committee of the AAPM. The objective of this SDEP is to fully understand and implement all aspects of the TG 51 protocol.
B. Approach:
A step-by-step guide to calibration of a linac's photon and electron beams using the TG-51 protocol will be written. The guide could be used by a medical physicist who is not yet familiar with this protocol to gain experience. A calibrated ion chamber, a water tank phantom, a calibrated electrometer, a lead foil for filtering electron contamination from a photon beam of 10 MV or greater, and temperature and pressure measuring devices are also required. Emphasis will be placed on explaining the definitions and the advantage in simplicity of using dose-based calibration, as opposed to the exposure-based calibration and cavity theory relationships used in the TG-21 protocol.
The formalism and dosimetry procedures recommended for TG-51 are based on the use of an ionization chamber calibrated in terms of absorbed dose to water in an Accredited Dosimetry Calibration Laboratory (ADCL) using a reference 60Co gamma ray beam. This is different from the recommendations given in the AAPM TG-21 protocol, which are based on an exposure calibration factor of an ionization chamber in a 60Co beam.
Step-by-step information will be provided on the following topics:
- Measurement of percent depth-ionization and depth dose curves for photon and electron beams using cylindrical and plane-parallel ionization chambers.
- Determination of the beam quality conversion factor k Q for photon beams and the electron beam quality conversion factor k’ R50 for electron beams.
- Measurement of various correction factors to the charge reading.
- Determination of dose at the depth of dose maximum from measurements made at the reference depth for both photon and electron beams.
- Measurements needed to compare the recommendations of the TG-51 protocol with those of the TG-21 protocol.
- Identification of expected differences in absorbed doses between TG-51 and TG- 21 for both photon and electron beams and the sources that contribute to the observed differences between the two protocols.
- Clarification of potential sources of confusion in the clinical implementation of TG-51.
C. Evaluation of Achievement:
1. Prospective Statement (Provided at the date SDEP is initiated):
Upon completion of the project, a guide will be prepared and posted on a university website for use by any person who wants to learn about TG-51.
2. Final Statement (Provided at the date SDEP is completed):
A report concerning TG-51 has been prepared that documents the above activities, date of completion, and data for all relevant findings. That report is available on the web to serve as a teaching guide.
D. Impact on Practice/Outcome Statement:
1. Prospective Statement (Provided at the date SDEP is initiated):
Completion of the guide to TG-51 will require a thorough understanding of the protocol, and will provide a useful resource for any medical physicist who wants to become familiar with TG-51.
2. Final Statement (Provided at the date SDEP is completed):
The implementation of the TG-51 protocol has benefited the institution in achieving a full understanding of the consequences of implementing the new protocol. It has aided in complying with the recommendations of the Radiologic Physics Center and consequently in achieving better standardization of the dosimetry. The comparative evaluation of patient entered in national clinical trials through study group such as RTOG is also placed on better scientific foundations.
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