FOR USE WITH CARESTREAM X-OMAT FILM PROCESSORS
Extended Dose Range (EDR) READY-PACK Film for Monitoring and Evaluation of Exposures at Therapy Energies
EDR2 film is the latest addition to our award-winning products designed specifically for oncology applications. Compared to most x-ray films, it is relatively insensitive to x-ray energies and, hence, has a response which extends to very high exposures. Intended for direct exposure applications, EDR2 film extends the current line of Ready-Pack products which includes PPL film. It is not suitable for portal imaging radiographs.
Film is a convenient means for calibration and monitoring of exposures.
- Large area
- Low cost, widely available
- Excellent for relative dosimetry (e.g., field uniformity, equipment characterization: field shapes, port openings, MLCs)
- With appropriate calibration, film may be applicable to absolute dosimetry (e.g., high-dose treatment strategies such as IMRT)
Features of EDR2 direct exposure applications
- Wide response range
- Approximately linear
- Robust processing
EDR2 Film – Dose Response for Evaluation
Exact dose responses are a function of facility dependent factors including processing conditions (processing time, processing temperature, processing equipment, processing chemistry), the density sampling (digitizer equipment and calibration), and exposure monitoring equipment. The exact response relationship should be measured and verified for the local conditions. The films should be processed using recommendations found in Service Bulletin #30.
The dose response of a film should be measured using appropriate amounts of build-up and backscatter material. Many references have discussed methodology for measuring the response of a film. A few of these are:
- M. D. C. Evans and L. J. Schreiner, “A simple technique for film dosimetry,” Radiother. Oncol. Vol 23, pages 265–267, 1992.
- J. I. Hale, A. T. Kerr, and P. C. Shragge, “Calibration of film for accurate megavoltage photon dosimetry,” Med. Dosimetry Vol 19, pages 43–46, 1994.
- Inhwan J. Yeo, C-K Chris Wang, and Sandra E. Burch, “A filtration method for improving film dosimetry in photon radiation therapy,” Medical Physics Vol 24, pages 1943–1953, December 1997.
- J. L. Robar and B. G. Clark, “The use of radiographic film for linear accelerator stereotactic radiosurgical dosimetry,” Medical Physics Vol 26, pages 2144–2150, 1999.