At Pyramid we are constantly developing our range of products and services. Watch this page for information on new products, product applications and software releases.
The Particle Therapy Cooperative Group 2018 conference in Cincinnati is approaching (PTCOG 57) and we hope to meet customers old and new at our booth, number 19. You will be able to see and handle diagnostic products like the large area IC256-45 imager for spot position calibration, the MLFC128 for routine energy validation and our pixelated and fine-pitch strip ionization chambers for beam trajectory and shape checking. Look out for news of the unique high-resolution, large area 2-D imager development. Every third visitor to our booth will be permitted a personal one-on-one meeting with the President (of Pyramid).
The planets have aligned. Coming to a planet ripe for advancement and new technology, the IC256-45 Monolith quality assurance ionization chamber is large enough at 45 cm by 45 cm sensing area to cover the largest pencil beam scanning field at isocentre. 256 strips in each axis give a 1.75 mm pitch, with typical beam spot position resolution of 0.2 mm or better.
This new detector saves time and removes uncertainty in the process of calibrating and checking the position of beam spots in a pencil beam scanning particle therapy system. With compatible dose delivery systems it can be linked to the scan control system for automated data collection and analysis.
The Monolith is available with a variety or readout options at different price points. It is also available for rental. Call us for more details.
The C400 pulse discriminator / counter and CP-10 pre-amp provides a fast multichannel pulse counting solution for scintillation detectors and similar devices with high multiplication gain, or for particles that create a large deposit of energy in the sensor. The detector signals are amplified directly by a wide-band DC-coupled circuit in the CP-10 which allows pulse rates of 10's MHz to be counted. However many detectors produce signals that are too small for this type of pulse processing.
The new CR-10 pre-amplifier combines a charge-sensitive integrating pre-amplifier stage with a Gaussian shaping amplifier and baseline restorer. The design is based on the well-proven high-performance modules from Cremat (cremat.com).
The excellent signal to noise performance allows small signals such as those from individual X-ray photons in proportional chambers or diode detectors to be counted. The CR-10 can be configured at time of order for optimum performance in a given application by selection of pre-amp conversion gain, intermediate stage gain, shaping amplifier time constant, signal polarity and input connector type. It is connected to the C400 using the same connectors as the CP-10 pre-amps.
Pyramid can supply everything from complete proton therapy nozzles to the building blocks to allow customers to build their own configurations. Two new products that assist this process are the FS-78 fast beam shutter and the HC-80 helium beampath controller.
The FS-78 was developed to handle the issue of beam trajectory control. Errors in beam trajectory translate to errors in dose placement unless counter measures are taken. Placing the FS-78 just before the beam scanning magnets allows a short beam pulse to be transported around the beamline, but without reaching the patient. The trajectory can be corrected, or the treatment map can be offset. The fast actuation of the FS-78 reduces the time penalty to a minimum.
The HC-80 provides a complete automated flow control and monitoring system for a helium-filled nozzle beampath. The system will purge and then maintain the helium concentration. Flow, pressure, temperature, orientation and residual oxygen levels are all tracked. The system keeps track of helium use, and warns when it is time to change the cylinder.
New external trigger modes have been added to the popular IC101 integrating electrometer. The External_Start_Stop mode waits for a trigger edge on the gate input, then makes integrations while the line is high. The External_Start_Hold is particularly suitable for applications where the signal is pulsed. Instead of stopping when the falling trigger edge is detected, the IC101 pauses acquisition, then resumes when the next rising edge appears, and so on. By appropriate setting of the length of the gate signals and the integration time, you can arrange the IC101 to take any desired number of readings per trigger cycle. The trigger pulses do not even need to appear at regular intervals.
The IC101 offers great flexibility in a compact, cost-effective and easy-to-use package. It has a dynamic range from 200 uA down to less than 1 pA. As well as the enhanced triggering, there is a wide range of high voltage options and multiple communication options. Real-time monitor outputs track the input signal as both analog voltage and a VFC-like frequency that can be fed to any suitable counter. The monitor outputs can be scaled by the user, and there is a log mode available for the frequency output.
The Pyramid G2 platform provides Ethernet connection either directly to products that have an Ethernet port, or via any of the loop controller products. The Pyramid IG2 service allows G2-enabled devices to connect via the EPICS layer, and thus to a wide variety of client software packages for data presentation and analysis.
The widely-used I400, I200 and I404 products from Pyramid have now been added to the list of devices that are supported under G2. Up to thirty devices connected in two fiber optic loops can be accessed through a single A360 loop controller, for example. Furthermore, G2 products such as the F460 and C400 can now be used as loop controllers to connect the I400, I200, I404 and IC101 in a similar way.
Lead software developer Kendall McCarthy comments "We have reproduced the broad functionality of the G1 Diagnostic software in the new G2 screens. The access to the IG2 EPICS service opens up many new options for users. We are always happy to hear from users about new features they would like to see in the software."
GI, G2 and IG2 software are included with the I400, I200 and I404 at no additional cost.
The I400 four-channel electrometer combines sensitive current measurement with the ability to bias the signal measuring circuit up to 400 V relative to ground. This makes it suitable for reading out miniature ionization chambers. These chambers typically provide the signal on an electrode which must be a few hundred volts relative to ground to bias the chamber. This feature requires the use of triaxial signal connections to eliminate unwanted leakage currents in cables and connectors.
Up to now the I400 has been supplied with 3-lug triaxial bayonet connectors. Customers may now request the widely-used TRT threaded triaxial connector. This allows direct connection of a wide range of proven dosimetry chambers.
The annual Particle Therapy Cooperative Group conference has become a big meeting since it first started in the early days of the technique. It is attended by all the important users and vendors of particle therapy systems.
This year the 55th meeting is in thhe historic city of Prague (ptcog55.org). Pyramid will be a sponsor will be showing its range of products and new developments, including the new CM100 treatment room console, ionization chambers, electrometers, Faraday collectors and isocenter diagnostics. We look forward to seeing our friends and hope you can find time to talk to us. If you want to schedule a meeting, please call and ask to talk to Sashi or Julia on +1 781 402 1700. Otherwise, call in to our booth any time.
Pyramid is pleased to announce that its processes for the design, manufacture and service of electronics, electromechanical and control systems for use in medical devices have been assessed against ISO 13485:2003 and declared compliant by BSI. Pyramid Quality Manager Marcella Garcia commented: "We have worked over several years to improve our working methods as part of our ISO 9001 process. As the company is extending its offerings in the particle therapy market, it was clear that we should also work to the requirements of ISO 13485. I should like to thank all my colleagues at Pyramid who contributed to this effort, and continue to do so an a daily basis."
Pyramid will be assessed against both ISO 9001 and ISO 13485 from now on, so that all aspects of its work, whether or not in medical markets, is done to the highest quality standards.
Pyramid measurement and control products are designed to connect to computer systems for operation and data taking. Many of the products have interfaces suitable for direct connection to a computer such as Ethernet, serial RS232/RS485 or USB. The smaller embedded products connect to the computer via a fiber optic loop controller like the A500 or A360.
Depending on the product, there are many host software options including:
- The Pyramid Diagnostic programs which are available for all products
- For the products with serial ASCII interfaces, you can create LabVIEW programs that talk directly.
- If you have access to a software development team, you can create your own host system using the PTCControls32 library.
Pyramid is creating a set of demonstration user interfaces for EPICS plus Control System Studio, EPICS plus LabVIEW and LabVIEW alone using a serial ASCII connection. Check the Downloads page for the latest examples, or call us if you wish to discuss interfacing a particular product.
The annual Particle Therapy Cooperative Group conference has become a big meeting since it first started in the early days of the technique. It is attended by all the important users and vendors of particle therapy systems.
This year the 54th meeting is in San Diego ((ptcog54.org)and Pyramid will be showing a range of products and new developments, including ionization chambers, electrometers, Faraday collectors and isocenter diagnostics. We hope you can find time to talk to us. If you want to schedule a meeting, please call and ask to talk to Sashi or Julia on +1 781 402 1700. Otherwise, call in to our booth any time.
The Faraday collector is a trusted and direct way of measuring the current of a particle beam. At its heart it is little more than an isolated and screened electrode that can be connected to a sensitive electrometer. The subtlety lies in controlling the secondary electrons that are released by the arriving ions. If these electrons escape from the device when it is measuring a beam of positive ions, the measurement is exaggerated and unreliable.
When the beam energy is high, such as the 50 to 250 MeV proton beams typically used for particle therapy, then there are additional challenges, but also opportunities. The collecting electrode must now be thick enough to stop the beam and the secondary particles it creates completely. But because the beam will travel a considerable distance in air, the Faraday collector can dispense with the usual paraphernalia of vacuum pumping and secondary electron suppression devices and become a compact and robust device that operates in air. The approach was pioneered for proton therapy by Bernie Gottschalk at the Harvard Cyclotron Laboratory. New developments in coating technology have now allowed commercial development of this convenient device, as illustrated by the Pyramid BC-60.
The same approach can be extended by making the beam stopping electrode into a stack of thin layers, each with individual electronic readout. The result is the multi-layer Faraday collector, also explored by Gottschalk, which provides, in addition to the total current, a direct measurement of the beam energy by determining its range in a well-characterized material. The Pyramid MLFC-128 makes this important technique available to the proton therapy community.
Ionization chambers with pixel electrode patterns provide true two-dimensional beam profiles. Strip electrode chambers assume that the beam can be characterized by two orthogonal one-dimensional projections. However some beam behaviors such as inclined elliptical beams are not well-represented by the projections - a true two-dimensional imager provides more information.
Pyramid has introduced 2D imaging chambers for particle therapy isocenter diagnostic purposes (the PX-2) and for in-situ beam profile monitoring (the PX-3). The PX-2 is available in a telescope configuration that measures the position, shape, trajectory and divergence of a beam. The PX-3 provides one of the lowest possible water-equivalent thickness beam position monitors for the particle therapy market. Go to the beamline diagnostics section of the Products page for more details.
Pyramid is now enjoying the benefit of its in-house laser patterning system. The system comprises a high stability optical table, an air-bearing X-Y stage and a unique UV laser and galvanometer arrangement. Ionization chamber electrode substrates up to 30 cm square can be machined to micrometer precision. New electrode patterns are created on a CAD system and translated to a motion path for the laser spot. A microscope and camera alignment system ensures that patterns on both sides of an electrode film are precisely aligned.
The patterning system is used for the full range of thin-film ionization chambers from Pyramid. It really comes into its own when we respond to enquiries for new chamber designs. New electrode designs can go from concept to completed films in days.
One of the present challenges of particle therapy is obtaining instrumentation with the appropriate specifications. These days, with the growing implementation of pencil beam scanning, the speed, resolution and calibration of the ionization chamber are critical parameters. Dr. Jay Flanz, Technical Director at the Francis H. Burr Proton Center at Massachusetts General Hospital requested Pyramid to supply ionization chambers which would be compatible with both their ongoing beam scattering delivery mode and also with their increasing number of pencil beam scanning treatments. One of the specifications included reducing the effective thickness of these chambers to minimize the beam scattering and resultant beam size growth, to enable achieving a smaller beam spot size. With a smaller beam spot size comes increased resolution requirements, so the system we provide would have to be compatible with that as well.
Pyramid designed and built a chamber assembly which was mechanically and electrically compatible with the MGH system. The system provides two independent dose electrodes, X and Y position-sensing strip electrodes and a dose density pad. Built-in desiccant ensures a stable low-humidity air filing, and environmental sensors provide automated readout of pressure, temperature and humidity inside the chamber envelope. Pyramid used its established thin film electrode technology. In addition, Pyramid’s internal chamber calibration test stand has demonstrated the better than 1% overall response uniformity, thus saving many hours of beam time that would normally have been used in calibrating such an instrument. The ionization chamber has been in continuous clinical use for 12 months for both scanning and scattering beam delivery and is operating with good stability and reliability.
In a further development, a special low-insertion length chamber with extremely low scattering has been developed to mount in the upstream end of the treatment nozzle. Instead of the strip readout electrodes of the existing chamber, the new device has a pixelated readout electrode. This provides true 2-D imaging of the beam, and is thus able to detect unwanted beam conditions that are hidden from standard strip electrode chambers. Pyramid is developing a software layer that allows the new chamber to also emulate a normal strip readout device, so that it integrates seamlessly with the MGH controls and software, however, developments are underway to fully utilize the potential of this new device. Note that tests with this chamber have resulted in a significant reduction of the beam spot size for scanning beams. This chamber is fully applicable for all particle therapy facilities and information is available upon request
spec from Certified Scientific Software (http://www.certif.com) is the most widely-used instrument control and data acquisition software for X-ray diffraction. The Pyramid C400 four-channel pulse-counting detector controller integrates wideband pulse discrimination, fast-scaling, high-voltage supplies, pre-amplifier power and several diagnostic features into a single unit. Pyramid has been delighted to work with Certified Scientific Software, with the result that the latest 6.02 release of spec now includes support for the C400 (spec C400 help notes).
The C400 is available to the synchrotron light source community through FMB-Oxford Ltd (http://www.fmb-oxford.com).
There are common requirements for ionization chambers used for dose measurement and beam spot measurement in particle therapy - stability, accuracy, and very low beam scattering and energy loss. Pyramid chambers all feature precision laser-machined thin film electrodes, integrated environmental sensors and de-humidification.
However users still need a range of chambers to cover different needs for active area, sensitivity, redundancy and the tradeoff between gain and high beam current capability.
The range of chambers available from Pyramid is growing, and is matched by multichannel readout electronics.
The IC128-25 offers 128 sensing strips in each axis and sensitive are 25x25 cm2, high voltage loopback and a dedicated integral plane for dose measurement.
The IC64-16 has 64 strips in each axis and 16x16 cm2 active area. It includes HV loopback and two independent dose planes with small gaps.
The IC16-5 has 16 by 16 strips and 4.8 x 4.8 cm2 active area. It has small (3mm) gaps and is intended for use upstream of a beam scanning system, for continuous beam position and quality measurement.
Custom and retrofit chambers are also available to order. A recent example is a large area 32 by 32 strip system with readout pad for double scattering systems installed and in use at Massachusetts General Hospital.
The launch of the H20 two-channel Hall probe system provides a compact, high performance magnetic field measurement system that is particularly suited to particle beamlines, especially two-axis magnetic scanners. The matching MFP-30 probe is thin but rigid, and has design features that make it well-suited to the measurement of DC and AC fields up to several kHz, and good resistance to background neutron and gamma radiation.
The state of the art Hall element has low inherent noise and temperature coefficient. The use of a high stability current source, on-board digitization and downsampling, temperature measurement at the probe tip and full temperature compensation gives excellent low noise performance and high stability.
EPICS (http://www.aps.anl.gov/epics/) is "a set of Open Source software tools, libraries and applications developed collaboratively and used worldwide to create distributed soft real-time control systems for scientific instruments such as a particle accelerators, telescopes and other large scientific experiments." Once data and controls for a device are available as process variables in the EPICS environment, then they can be accessed by a wide variety of client systems, including programs written in C++, C#, Java, Python, LabView™, Matlab™ and others.
Pyramid has released an EPICS connection for its products using the EPICS Channel Access Server, embedded in the Pyramid IG2 program. The IG2 service runs on any suitable host machine on the network to make all the defined devices and their process variables available to your client application, which can be running anywhere else on the network. Any Pyramid product that can communicate over Ethernet, either directly, or via a fiber optic loop controller, can be connected to EPICS this way.
The rich variety of applications in the EPICS community includes help for non-programmers too. Control System Studio (http://controlsystemstudio.github.io/) allows the rapid development of quite sophisticated user interfaces in very short time. As an example, the user interface for the F460 and M10 products shown here was created and debugged in the CSS BOY editor in less than one day.
Pyramid is shipping the new F460 current monitor. A member of the G2 range of devices, it includes four fast, parallel and independent current measurement channels with excellent accuracy and stability, integrated precision current sources for fully automated self-calibration, deep buffer memory for high rate acquisitions, analog voltage and TTL frequency monitor outputs and comprehensive triggering modes.
Communication is via Ethernet, serial/ASCII or fiber optics. High voltage output and servo controller options are available.
The F460 is available to the synchrotron light source community through FMB Oxford.
The Pyramid M10 general-purpose I/O device has sold widely as a means of connecting devices such as power supplies to large control systems. It is now joined by the M40, which provides four times the analog input and output capacity, and twice the digital input and output capacity, but in the same small package. It has already found application as an interface to multiple beam steering magnets on a particle accelerator beamline.
In addition to providing precision analog and digital control, the M40's powerful FPGA provides the power and memory to allow the M40 to act as a multichannel waveform generator and data logger. Visit our Products pages for more details.
Ionization chambers are widely used in particle therapy systems both for beamline setup and dosimetry. It is important, particularly for dosimetry, that the correct high voltage bias is applied to the chamber, otherwise the beam current may be incorrectly measured. Pyramid electrometers that were specifically designed for particle therapy dosimetry include a high voltage loopback feature that allows positive sensing that high voltage has reached the ionization chamber. However there is a need to provide similar capability for legacy systems, and so Pyramid has developed the HVI-4 ionization chamber bias interlock.
The HVI-4 provides four channels of hardware interlocking for bias voltage. Absolute value comparators sense whether the voltage is within tolerance of a selectable setting. If the readback is out of tolerance a safety relay opens, which the user can connect to a interlock system. The HVI-4 also features a passive monitoring port that allows a control system to keep watch on the sensed high voltages, the setpoints and the status of the relays. Visit our Products pages for more details.
Beam position monitors (BPMs) based on position-sensing ionization chambers are a vital diagnostic for the high energy beam transport systems used in particle therapy. Pyramid has developed a compact BPM with 16-strip sensing in each axis and pneumatic actuation that moves the sensor completely clear of the beam path when measurements are complete. Precision PCB lithography methods used on thin electrode substrate material offer excellent measurement precision. A major particle therapy customer has ordered the BPM16-38, and deliveries are underway. Earlier, we were grateful to Massachusetts General Hospital for allowing us to do high-dose testing, equivalent to years of operation, in the experimental room at the Francis H Burr Proton Therapy Center.
The BPM16-38 is matched by the best-selling I3200 electrometer to provide a complete beam position readout and control sub-system. Other features include dual redundant limit-switches, a choice of vacuum flange type and a choice of atmospheric air or flow gas filling. Visit our Products pages on this site for full details.
Pyramid has been working with researchers from the University Clinic of Heidelberg, the Heidelberg Ion Beam Therapy Center, and GSI Darmstadt to provide high performance readout for a multilayer IC stack used to measure Bragg curves due to the stopping of high energy ions. Eventually this detector technology may allow real time tracking of energy loss in particle therapy patients, and thus the position of organs inside the body as the treatment proceeds. A Bragg curve of good resolution is needed for each position in a scanned beam treatment map while giving the patient the lowest possible additional dose (ie the lowest number of delivered particles per beam raster point). Moreover, the technique requires sensitive current measurements at high data rates over a large number of electrometer channels (I Rinaldi, PhD thesis).
Promising data has already been obtained with the I3200 electrometer. In the last few weeks a prototype of the new Pyramid I128 electrometer was tested at the Heidelberger Ionenstrahl-Therapiezentrum (HIT), which is one of the few places in the world where high energy ion beams of both protons and carbon nuclei, with programmable energy, intensity and focus, can be delivered to order. The I128 provides 128 electrometer inputs which will allow an increase in the number of channels in the detector, and it measures all channels simultaneously with integration periods down to 55 usec. It has extensive on-board data buffering, calibration and processing capability, and can even provide bias voltage for the detector.
The data snapshot here shows instantaneous Bragg curve measurements.
In a set of experiments designed to explore the sensitivity, dynamic range and data rate capabilities of the detector/electronics combination, we were able to propose some enhancements to the detector and to the I128 firmware that will move this interesting method nearer to clinical use. Look out for more news on the I128 product soon.
Our offices in Lexington MA are in a great location, with convenient travel to many of our US customers, but it was getting to be a squeeze. So when the place next door became available, we took the opportunity to double our space and improve our operations.
A new clean manufacturing test area has been set up for our range of electronics and beamline instrumentation. The old manufacturing area is now dedicated for engineering development. Full segregation between production inventory and engineering materials is possible now. Please come by!