Logos Chevron Wedge 300

The LCW-300 is a PTFE dual wedge that can be used to measure Proton beam and X-ray depth-dose relationships. It was specifically designed to quickly provide accurate proximal edge measurements of an ion beam’s Bragg peak penetration range. The height of 171 mm allows proton beam equivalent penetration depths in water of up to 300 mm to be captured on a detector. The LCW-300 enables a wide range of Bragg peak measurements to be taken quickly with a typical average accuracy of 0.5 mm.

The chevron wedges overlap so that measurements on the edge of one range can be duplicated at the beginning of the next. The wedge angle of 45 degrees enables symmetrical measurements to be made on each side of the center line and averaged for greater precision. Each wedge is 24 mm thick.

The small 152.5 × 205 mm footprint allows the LCW-300 to be placed above the scintillator of any Logos Systems 2D detector, including the XRV-2000 Falcon, XRV-3000 Eagle, and the XRV-4000, so that measurements can be taken quickly and easily. A set of rotation hardware is available to mount the wedge securely on Logos Systems 2D detectors in order to take measurements at any gantry angle.

The PTFE composition of the LCW-300 has a water equivalent density of 1.8 for direct proton range verification up to 300 mm. More energetic beams can be accommodated by padding the bottom surface with additional PTFE, acrylic or tissue equivalent plastic. The patent pending design may be enhanced with additional chevrons, so please contact us for custom configurations.

Features and Benefits:

• Quick Bragg peak measurement of water equivalent Proton beam penetration depths up to 300 mm
• 171 mm tall
• PTFE composition
• Full range Bragg peak measurements in under 5 minutes
• Measurement accuracy typically 0.5 mm
• Measures Proton and X-ray beam depth-dose relationships
• Mounting hardware available for XRV-2000/3000/4000 for use at any gantry angle
• Compatible with film
• Automated image analysis and software measurement
• 35 energy layer Excel analysis template provided

The LCW-300 is aligned with the treatment room lasers on the XRV-2000, XRV-3000, or XRV-4000 phantoms so that the Logos Systems software can perform automatic measurements of the symmetrical Bragg peak regions produced on the scintillator below the target.

The WinLVS capture software has a built-in scripting language that facilitates automatic real-time capture of the multi-energy even-dose delivery pattern needed for Bragg peak range measurements.

After each layer has been delivered, WinLVS merges the captured PBS image streaks to form complete radiographs. Once the 35 layers of the plan have been delivered, the Bragg peak regions on the radiographs are isolated and measured with the CSV formatted data being output to file. This CSV file can then be imported into an Excel template where the Bragg peak penetration depths are calculated.