Sensitive to doses ranging from 1cGy to 800cGy.

• Develops in real time. There is no post-exposure treatment.
• Eliminates processing discrepancies.
• Density changes stabilize rapidly after exposure.
• Energy-independent dose response from keV to MeV.
• Eliminates concerns caused by scattered radiation.
• Near tissue-equivalent.
• Uniformity better than 1.5%.
• High spatial resolution.
• Can be handled in room light.
• Eliminates the need for a darkroom.
• Water resistant.
• Usable in water phantoms.
• Will withstand temperatures up to 70°C.

Some of the economic benefits are:

• Film can be marked with marker pen and erased if necessary.
• Size and shape the film to your needs.

• Significant savings

Configuration and Structure of Gafchromic^® EBT

GAFCHROMIC^® EBT is made by laminating two active layers bonded together. The outer surface is polyester that makes a robust product and allows water emersion.

Optimizing the Sensitometric Response of Gafchromic^® EBT Dosimetry Film

Since the absorbance spectra of GAFCHROMIC^® EBT peaks at 636nm, the sensitivity is maximized by measurement with red light.

Transmission densitometers that are commonly used to measure visual density with conventional films are suitable for use with EBT film. Better results can be obtained from the red color channel with a color densitometer. However, the best results can be obtained by using a narrow band pass filter with central wavelength at about 636nm and 10nm bandwidth while making measurements.

GAFCHROMIC^® EBT dosimetry film can also be read with a film scanner or digitizer. As with densitometers, the response of the film will be enhanced if the spectral response of the scanner is matched to the absorbance of the film.

Many high-quality scanners are designed to digitize colored films. Our preferred scanner is an Epson^® flatbed color scanner designed to digitize colored films up to 8” x 10” and even as large as 12” x 17” in size. These color scanners provide the best response for the EBT film from the red color channel. Black-and-white scanners usually employ a broad spectrum light source and this will usually result in a lower response with EBT film.

HeNe laser scanners (Lumisys, Molecular Dynamics) provide the highest response with EBT film because the laser has a wavelength of about 633nm, very close to peak absorbance. However, the coherent light of the laser scanners can produce artifacts caused by the interaction of polarized light with the film. These artifacts can be minimized, if not eliminated, through the use of a diffuser in the beam path.

Energy Independence of Gafchromic^® EBT Dosimetry Film

GAFCHROMIC^® EBT radiochromic film has been designed to measure absorbed dose from high-energy radiation used in IMRT. The response to photons has been found to be energy-independent in the MeV range and measurements at lower energies show that the response changes by only a few percent, even down to 30keV

The response of GAFCHROMIC^® EBT dosimetry film is dependent upon factors specific to the facility such as the energy spectrum of the radiation source, the characteristics of the densitometer, film scanner or other means of measurement and the elapsed time between exposure and measurement etc. Therefore, the user should determine the dose-density response under the conditions pertaining to the user’s facility and measurement protocol. Since the absolute response of GAFCHROMIC^® EBT dosimetry film may vary from lot to lot, the user should re-measure response when changing to a new lot number.

Dose Fractionation

The results in the table below indicate that the response of EBT film exposed to a single fraction is indistinguishable from the response of the film given fractionated exposure and establishes EBT film as an effective dose integrator.

Response of GAFCHROMIC^® EBT Dosimetry Film to Fractionated Exposure

Post-Exposure Density Growth

GAFCHROMIC^® EBT film develops in real time. When calibrating and analyzing films, the time interval between exposing the films and scanning them should be consistent for all films.

Storage and Handling

GAFCHROMIC^® EBT film is designed to be handled in interior room light but it is recommended that the film be kept in the dark when not in use. Exposure to sunlight should be avoided. The film may be stored at room temperature (20°-25°C), but the best practice is to store the film at refrigerator temperature. The shelf-life of the film is two years when stored at room ambient temperature. It can tolerate brief exposures (e.g. <1min.) to temperatures up to 70°C, or more prolonged exposure (e.g., <1 day) at temperatures of 50°C. However, it is recommended that the film be handled, exposed and measured at room ambient temperature (20°-25°C).

Film Size

GAFCHROMIC^® EBT – 8” x 10”

GAFCHROMIC^® EBT-1417 – 14” x 17”

A reliable performer that’s sure to increase productivity this hardworking scanner features Epson’s exclusive ColorTrue® II Imaging System, which combines superior image processing, a Xenon lamp, and Epson MatrixCCD^TM technology for enhanced colors and pinpoint registration. Its 3.8 Dmax delivers a broad dynamic range with excellent shadow detail. And, an AutoFocus optics system, when activated, adjusts the focus and captures clear, precise images every time.

The Epson Expression 10000XL scans virtually anything, including reflective media up to 12.2" x 17.2." And, it’s available in two configurations – a Photo model, with a transparency unit for scanning transparencies up to 12.2" x 16.5" and a Graphic Arts model. Each includes both USB and FireWire® (IEEE 1394) connectivity for most Windows® and Macintosh® systems. There’s also an optional network card.

Best of all, these durable scanners speed through every task to digitize images quickly and easily. They even offer an optional automatic document feeder for multiple-page scanning. For increased productivity and remarkable results in professional graphic arts and photographic applications, the solution is simple – the Epson Expression 10000XL.

Extraordinary image quality with 2400 x 4800 dpi resolution

Works together with Micro Step Drive^TM technology to deliver brilliant clarity and detail

Smooth gradations with 48-bit color

Captures over 4 trillion colors and 4,096 shades of gray

Convenient large-format scanning

Accommodates reflective media up to 12.2" x 17.2"

Enhanced color with ColorTrue II Imaging

Combines superior image processing, a long-lasting Xenon lamp, and Epson MatrixCCD technology for bold, vibrant scans

3.8 Dmax for precision reproductions

Accurately scans each image, including film and transparencies, for remarkable precision, even in shadow areas

Quick scans with Hi-Speed USB and FireWire connectivity

Enhanced operation for most Windows or Macintosh systems

Powerful performance with fast scanning speeds

Speeds through an 8.5" x 11" color image at 300 dpi in under 23 seconds

Batch scanning for increased productivity

Scans multiple images at one time and saves files to a PC (scans up to 48 35mm negatives, 30 35mm slides, eight 4" x 5" transparencies or six medium-format transparencies)

Production level reliability

Boasts a 100,000 cycle MCBF (mean cycles between failures) rating

Light-field and radiation-field alignment

Precision star shots

Position verification for HDR

Autoradiography of implantable seeds, plaques and other sources

GAFCHROMIC® RTQA was designed for routine quality systems management of all modalities of radiotherapy with ease and confidence. It is a user friendly, cost effective, reliable and simple tool to meet quality assurance objectives.

This self-developing radiochromic film is ideal for use in the film-less environment of the modern hospital and has the following characteristics:

• Dynamic range from 0.02 Gy to 8 Gy
• Develops in real time. There is no post-exposure treatment
• Eliminates the need for a processor
• Eliminates chemical waste
• Can be handled in room light
• Eliminates the need for a darkroom
• Convenient to handle and easy to cut
• Size and shape it to your needs – use only what you need for the job
• Water resistant
• Immerse it in a water phantom
• Competitively priced with conventional films

Qualitative Dosimet

For faster, easier, more convenient and less costly QA testing of radiotherapy sources and the commissioning of therapy equipment:

• Light-field and radiation-field alignment
• Star-shots
• Positioning verification for HDR
• Autoradiography of implantable seeds, plaques and other sources

Why Use GAFCHROMIC^® RTQA?

• Hassle free:
• Just position it, shoot it and look. Why spend your valuable time going to a darkroom and waiting for film to developµ You don’t need a darkroom, you don’t need a processor.
• Simple and precision built:
• Just position it, shoot it and look. If the light field isn’t aligned with the radiation field you see it immediately and adjust. Eliminate the time spent for repetitive exposures, measurements and adjustments.
• Cost effective:
• Just position it, shoot it once and look. Make your adjustments and move on. You won’t need to spend your valuable time on second and third tries and waste extra pieces of film.
• Why use a large film for a small jobµ Why waste money on film that’s not getting exposedµ With GAFCHROMIC® RTQA you can size and shape the film to suit the task.
• Offers multiple solutions
• Couple your creativity, experience and knowledge with GAFCHROMIC® RTQA and you’ll find even better use like watching the effect of exposure in real-time on the monitor.

Sensitivity of GAFCHROMIC^® RTQA

The response of the GAFCHROMICRTQA film is dependent upon factors specific to the facility such as the energy spectrum of the radiation source, the characteristics of the densitometer, film scanner or other means of measurement, etc. Hence the user should determine the dose-density response under the conditions pertaining to their facility. Since the absolute response ofGAFCHROMICRTQA may vary from lot to lot, the user should re-measure response when changing the lot number.

GAFCHROMIC^®RTQA for HDR Application

GAFCHROMIC^®-RTQA -111 which is 1.25”x11” in dimension is aimed for HDR positioning verification. It is designed to be used in phantom or directly taped under a catheter. Mark the catheter position with a pen and check the autoradiographic image against the marks. A key advantage of the RTQA-111 strip is stability and alignment. It eliminates the concern about film movement inside a ready pack thus increasing the accuracy of measurement. With dwell time anywhere between 0.5 sec to 2.0 sec and depending on the source, RTQA-111 film exhibits sharp images clearly showing source position.