Putting image-guided radiotherapy to the test

Early adopters are exploiting a novel motion phantom to explore the possibilities of real-time magnetic-resonance guided radiotherapy for improved cancer treatment and neurosurgery

Photo of the QUASAR motion phantom from Modus QA — The QUASAR motion phantom from Modus QA allows researchers to explore a range of patient scenarios

Upcoming techniques based on magnetic-resonance guided radiotherapy (MRgRT) could enable clinicians to compensate for patient movements to a much higher degree, thanks to the clarity offered by MR imaging. Real-time tracking methods that can pinpoint changes in the position of a tumour translate to improvements in dose conformality by keeping radiation on target and sparing healthy tissue.

As vendors, early adopters and clinicians bring new ideas to fruition, a key part of their success depends on having the right development tools, which includes motion (or 4D) phantoms. Accurate models give researchers the chance to safely explore solutions for overcoming hurdles that can be faced in the clinic as a result of tumour motion. Scenarios include when a patient breathes, causing organs and tumours to move, or when there’s peristaltic motion through the digestive system.

We’ve designed our system to be compatible and expandable, and even – to a certain degree – customizable

Enzo Barberi, director of MR product development at Modus QA

Tumour movement has always challenged cancer treatment and manufacturers have worked hard to mitigate the issue as much as possible.

“Image guidance for radiation therapy has been around for well over a decade and most linacs have some form of cone-beam CT or EPID imaging that allows to them to roughly see where the target is,” says Enzo Barberi, director of MR product development at Modus QA – a developer and manufacturer of quality assurance tools for advanced radiotherapy and medical imaging. “But those imaging techniques provide little information about soft tissue.”

In contrast, MR imaging can reveal soft tissue in exquisite detail, which – when linked to a radiotherapy system – shines a welcome light on where the cancer is at any moment in time.

Barberi, who’s been working in this field for almost three decades, confirms that it’s a very exciting time in terms of the technology and the clinical development of next-generation techniques exploiting MR linacs. “In both systems that are available today, you can image while you are applying radiation,” he points out.

Real-time imaging hits the target

On-board MR imaging offers numerous possibilities for advancing radiotherapy treatment. For example, if gas happens to pass through the intestinal tract of a patient during radiation treatment, real-time MR imaging can detect whether the tumour has moved. And, if the target is now positioned outside the safety margins, the beam can be turned off until the gas has passed through and the tumour moves back into position.

“It’s a dramatic example of how the combination of these two techniques in parallel and in real-time can make a big difference in terms of accuracy in hitting the target when it’s moving,” Barberi comments. Real-time imaging using MR could also see the end of so-called gating, where patients are required to hold their breath to keep their chest stationary – a development that could speed up treatment as well as reducing discomfort.

Bringing these new techniques into the clinic requires reliable tools for quality assurance (QA). MRI-compatible models make it possible to test the ability of novel imaging sequences to track a wide range of movements – such as those resulting from respiration. Verification is important too.

“Using phantoms like Modus’ programmable QUASAR MRI 4D motion product in combination with dosimetry inserts allows early adopters to calculate and measure the dose that is administered to a moving target and ensure that they are actually hitting this moving target and not the surrounding healthy tissue,” says Barberi.

These early adopters are important beta-testers for Barberi and his team, as they are at the frontier of MRgRT. Users require a phantom design that’s flexible, practical and easy to deploy, allowing them to gather as much data as possible for a range of possible patient scenarios.

“Modus focuses very heavily on workflow as we understand that time on the system is valuable,” Barberi comments. “If we can make our QA tools and QA procedures fast and efficient then sites are not only more likely to use them, but they will also appreciate the fact that we’re not taking up a lot of their magnet and linac time simply for setup or integration or when they have to switch over from one mode of measurement to another.”

Early adopters drive development

Features of the QUASAR motion phantom include a spherical target that can mimic numerous trajectories of a tumour in the body, including those seen during breathing. “We can add not only linear motion in and out of the phantom, but we can also add twist and offset that sphere so that it follows a complex 3D path as time plays out,” Barberi explains.

His team acknowledges that different investigators will have different demands, such as when it comes to dosimetry. “Users may wish to use ion chambers or film dosimetry or 3D gel dosimetry,” Barberi notes. “So we’ve designed our system to be compatible and expandable, and even – to a certain degree – customizable.”

Barberi’s group is already working on a second wave of inserts for the MR-safe motion phantom, thanks to the early-adopter programme. The new inserts will focus not just on soft tissue sites, but also modelling deep organ areas and more complex types of motion.

First UK radiation treatment using MR-guided linac

There is no shortage of challenges coming down the pipeline, but Barberi has a great team and is confident in Modus’ approach – having seen its flagship products develop successfully along a similar path. “Working with many different clinicians, physicists and OEMs over the years, we have families of different inserts that we can draw upon,” he says.

Barberi describes MRgRT as a “game changer”, and companies such as Modus are part of a big global effort to support upcoming advances that serve to accelerate the adoption of MR-linac systems for clinical treatment. Initiatives include STARLIT (System Technologies for Adaptive Real-time MR image-guided Therapies), a consortium developing techniques for next-generation motion compensation that includes two large equipment vendors – Elekta and Philips – along with small- and medium-sized companies and academic centres. “We are also equally proud to be a partner with ViewRay, supporting the requirements of an equally respected vendor, and their early adopting customers,” he says

Original Source: https://physicsworld.com/a/4d-phantom-eases-route-to-adaptive-mr-guided-radiotherapy/

Original Date: Sept 25 2018

Radiation Therapy: Equipment Used by Veterinarians

When many of us think of cancer and how it affects us and the lives we lead we are more often than not picturing human patients however, we are not the only ones that affected by cancer. Today’s post is all about cancer in our pets and how their treatment includes similar treatment plans and medical equipment. Just like in the treatment of cancer within humans, pets use radiation therapy in various forms to shrink and kill tumors.

Radiation therapy delivered to pets can take various forms with the most common form of radiation treatment being delivered via linear accelerators with multi-leaf collimators. The multi-leaf collimator moves while the radiation treatment is on and being delivered to the patient. This allows the radiation therapist to sculpt the treatment around the tumor with very little damage done to cells outside of the area.

Another form of radiation therapy that is used to administer radiation treatment to pets and humans alike is Cyberknife, a linear accelerator that is paired with a robotic arm. This combination allows the machine to move around the patient. The radiation beam is turned off and on and is able to deliver radiation to the tumor from several angles. This ensures that the treatment conforms to the shape of the tumor within your pet.

Treatment can also be delivered through a Tomotherapy machine. A Tomotherapy unit is best described as a mix between a LINAC and CT scanner. It allows an image to be taken of the tumor right before radiation treatment is delivered. The therapist uses the images that are produced to guide radiation treatment to the tumor.

Tumors of the brain are treated with a very specific method of radiation known as the Gamma Knife. The word knife in the name may lead you to believe that cutting is involved however this is not the case. What occurs in Gamma Knife treatment is that very high doses of radiation are delivered to a very specific location on the brain while avoiding normal brain tissue.

As with humans, radiation therapy can be prescribed to pet patients through a variety of methods. One method is known as hyper-fractionated which means that many small doses of radiation are delivered to the pet with the goal being complete eradication of the tumor. This method is most often considered after surgery has been performed when there are small bits of the tumor left behind. Another method is known as hypo-fractionated in which radiation therapists use large doses of radiation in order to treat tumors that cannot be removed through surgery.

A more advanced scheme of delivering radiation treatment are Stereotactic Radiation Therapy, SRT. This includes both SRS, Stereotactic Radiosurgery, and SBRT, Stereotactic Body Radiation Therapy. These methods both deliver high doses of radiation in one, two, or three treatments.

Radparts is the world’s largest independent distributor of OEM replacement parts for Linear Accelerators and Radiation Oncology equipment. Radparts provides high quality, user friendly, low cost parts support for linear accelerators and radiation equipment. More information can be found at https://www.radparts.com/.

General Radiotherapy Machines

The most common machine used to distribute external beam radiotherapy treatment is known as a linear accelerator or LINAC for short. LINAC systems generate high energy x-rays that are carefully aimed at the cancerous tumors. This process is done with much care given to direct the rays in a manner that does as little harm as possible to the healthy tissue surrounding the tumor. Linear accelerators are used to treat cancerous tumors on all areas of the body.

Some LINAC systems that are more advanced have the capability to deliver radiation on or near the surface of the skin. In this type of treatment electrons are used in replacement of high energy x-rays.

Newer linear accelerators have the ability to deliver radiation using Intensity Modulated Radiation Therapy, IMRT. These systems use multi-leaf collimators adjust the shape of the radiation beam to match the shape of the tumor. Without these adjustments LINAC systems would only be able to shoot radiation beams in the shape of a square or rectangle.

Radiographers all have different methods that they use to make sure the radiation treatment is targeting the exact location of the cancerous tumor. In its most fundamental form radiation is just a plain x-ray. Most linear accelerators work through digital imaging where the bottom arm of the machine takes an EPI, electronic portal image, or PI, portal image.

The image is compared by radiographers, to images that were generated during the planning process of your treatment as a type of checks and balances before treatment is delivered. The quantity of images that are taken to compare between depends on the departments protocol for imaging. Different types of radiotherapy treatment machines have an On-Board Imager, OBI, that is comprised of a Kv x-ray and detector. Higher quality images are obtained as a verification which allows for another radiotherapy technique known as Image Guided Radiotherapy, IGRT. With IGRT the accuracy of treatment is improved as daily changes are accounted for such as changes in organ location which can in turn reduce unpleasant side effects.

Electrons are generated and speed up to almost as close to the speed of light using electrical fields. The energy continues to increase until it collides with its intended target and then releases the photon energy. These photons enter the patient in an attempt to break down the DNA cells in the cancerous tumor. Healthy cells are most often able to mend themselves where as the cancerous tumors don’t and eventually die.

The Lifespan of a Linear Accelerator Parts

A linear accelerator has a wide range of built-ins that are designed to ensure patients are only given the recommended dose of radiation. The dosage recommended by the physician should never be ignored or changed as each treatment dosage is unique to each patient. Linear accelerators are comprised of several parts and mechanisms that age over time. This article will go over what facilities can expect when it comes to the average lifespan of the parts on LINAC systems, CT scanners, and other radiation oncology devices.

The Lifespan of Linear Accelerator Parts

The lifespan of linear accelerator equipment comes down to two major elements: usage and maintenance. On average medical facilities can expect that large scaled radiation equipment, such as linear accelerators, to last around 5 to 10 years before they begin to break down. Regular maintenance of your LINAC system keeps it running smoother, longer.

Examples of medical equipment lifespans are:

High use parts like Magnetron and iView detectors can last upwards of two to three years and with average use around four to six years.
X-ray tubes with high use last about eighteen months however with low usage can last if four years.
XVI detectors can last up to ten years within linear accelerators that have low usage whereas with high usage XVI parts last around five years.
Thyratron tubes have a lifespan of anywhere between three to five years.

Age and Usage of LINAC Parts

The average life expectancy of most linear accelerator parts depends on the legitimacy of the parts and the amount they are used. There are some parts that need to be replaced yearly with increased use, like the electron gun, however with low usage can last upwards of six years.

Environmental factors cannot be ruled out as it also affects the ion chamber of a linear accelerator, high humidity can cause a reduced lifespan. While an average ion chamber will only need a replacement after four years, one in an environment with high humidity will need a replacement after a year.

When to Replace Aging Parts

Replacing aging parts over time is necessary to avoid causing any damages to the equipment. Some corporation has a habit of considering the price of the equipment and the costs involved in changing the parts over time, and as such delayed the immediate replacement of an overdue or overused equipment. But, this is never a good yardstick of profit maximization, in the long run definitely, a breakdown of significant parts of the system may be disastrous to the equipment.

As a Linear Accelerator stays over time and ages, errors can creep in and this will have an adverse effect on the accuracy of the equipment. It is reasonable to expect a good 5 to 10 years of use out of the linear accelerator, but the maintenance also takes its toll on expenses if it stays much longer.

Companies can often get more usage out of a machine and ensure errors are resolved or controlled just by keeping the software up to date and replacing or upgrading linear accelerator parts as at when needed. Most importantly it is advisable to choose a reputable company to replace your LINAC’s aging parts as the wrong equipment can end up creating more damage to the machine instead of improving its performance. Most companies who sell linear accelerators and parts will have service contracts available that offer varying levels of support.

Preventive Maintenance Increases the Lifespan of LINAC Systems

LINAC systems are just one of the methods that facilities use to administer radiotherapy to patients with cancer. The high cost of this technology necessitates that preventive maintenance be routinely undertaken to extend the life span of linear accelerator parts and other radiation oncology equipment. Linear accelerator parts should be serviced to ensure high quality service delivery to patients. This will go a long way in helping cancer patients to access quality treatment.

The main parts of LINAC systems consist of linear accelerator wave guide and the beam defining system. Other parts include: handle control, couch with controls, touch guard and wall panel to hide stand. Being that it is electrical equipment and it’s in continuous use, the systems will breakdown if not cared for properly which will lead to system breakdown. Therefore, preventive maintenance should be regularly done to ensure that the system works effectively and efficiently. A complex system such as linear accelerators and ct scanners depends on electrical connections, once there is poor connection the machine will malfunction. All parts work in cohesion and if one of them is faulty it will affect other parts.

Linear accelerator parts are expensive and the cost of purchasing a new one is prohibitive. Proper preventive maintenance should be carried out from time to time. Most LINAC systems use water cooling because a constant temperature need to be maintained to ensure harmonious operation. However, there is advanced air-cooled chillers for LINAC cooling. This cooling system is expensive but once it is replaced the system works as if it is a new one.

LINAC parts can be procured from the original equipment manufacturer or through local dealers. There are many advantages to buying parts through companies that offer several parts (and services) instead of a more expensive OEM dealer. Often these companies offer less expensive, refurbished options and OEM parts with warranties. If the parts should malfunction within the period of coverage of warranty, they can help. However, one important decision one must make is that whether one should buy refurbished parts or new OEM parts. Refurbished parts are suitable for repairs and maintenance and the cost is lower than buying new ones. This decision is often mostly decided because of your budget however, just know that refurbished parts are just as reliable and as effective so either way you are getting quality parts.

A lot of factors need to be considered when servicing or maintaining LINAC system. One of such considerations is the response time of maintenance company versus original equipment manufacturer. The response time of maintenance companies tend to be quicker than that of the original manufacturer. Therefore, procuring the service of maintenance company will shorten the downtime of the medical equipment. Associated with this is the high level of expertise of engineers working with servicing and maintenance companies.

In most cases, these engineers were trained by original equipment manufacturers hence, the quality of service delivery. Another advantage of servicing and maintenance of linear accelerator parts is that servicing companies have favorable and flexible contract agreement, and this ensure that servicing of equipment is done comprehensively with minimal costs. This contract agreement includes periodical preventive maintenance without extra costs. Routine service and maintenance of LINAC parts are necessary for optimal functioning of the system and it greatly reduces the amount of downtime of the equipment and elongate its lifespan.

Learn more about Radparts and the variety of services and parts they offer to repair medical equipment including: linear accelerators parts, CT scanners parts, linac parts, and radiation oncology equipment at www.radparts.com. To contact one of our medical equipment repair specialists for parts or service call toll free 877.704.3838 for 24/7/365 support.

Finding Parts and Services for Medical Equipment Repair

Healthcare businesses will often find that while their oncology equipment is in excellent shape, there comes a time when something will breakdown or break all together. When that happens, there is usually a ruckus, because then someone needs to find out who sells parts or services their linear accelerator or other oncology equipment. While this may seem easy, it is not as easy as it appears, especially because the company that is hired must excel in the work that they do and the oncology equipment parts that they provide.

There are numerous linear accelerator parts and oncology equipment parts that are needed when things go wrong, and Radparts has more than sixty-five thousand parts in our warehouse. That means that whatever you and your patients need, we have it in stock and ready to use.

Whether your linear accelerator needs a new MLC motor, console keyboard, or a new pump, you will not need to spend days waiting for a replacement. Instead of shuffling patients around, and trying to fulfill their needs, you can have your oncology equipment repaired quickly and be ready for your next patient right away.

Knowing where to find parts for your oncology equipment and knowing who can service them all is key to keeping your patients safe and healthy during their treatments. You never want to take a risk and use a linear accelerator or any other oncology equipment that has a broken or missing part, as that can put your patients in danger.

Instead, you will want to inspect your linear accelerator and other oncology equipment every day and have routine maintenance and outside inspections completed too. The sooner you notice an issue, the easier it will be to have everything fixed and up and running again. After all, no oncology unit will be able to function properly without this equipment and patients can suffer significantly from a broken-down machine as well.

Whether you have a brand-new linear accelerator or a completely refurbished one, you will want to have someone on hand for service and parts right away. While you may hope that you do not need their services for a long time, you will quickly find that things do not always work out the way that you plan. Therefore, a little pro-action will go a long way when the inevitable does happen and you need linear accelerator parts or other oncology equipment parts and services.

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Proper Maintenance Keeps Medical Systems Running Smoothly

The manufacturer of all medical equipment routinely establishes a regular maintenance schedule that customers need to be able to accomplish in order to ensure that their system is running properly. These maintenance requirements ensure tests are run to ensure that certain linear accelerator parts are all functioning well. The same is true for oncology equipment parts.

Importance of doing regular proper maintenance

When the equipment you are operating is designed for diagnosing a wide range of serious injuries, illnesses, and diseases it is extremely important that they are working optimally at all times. To be sure that all of your machines are properly maintained you should read all of the documentation that comes with each machine and pays close attention to any section that lists regular or scheduled maintenance.

8 Steps Involved in Quality Preventative Maintenance Plans on Medical Equipment

#1 Get the key people in your organization on board with the plan

– In order for any maintenance plan to work you need to be sure that you have all of your people on board with your plan.

#2 Discuss your goals for the plan –

Be sure to discuss all of your goals for the program with everyone to be sure everyone understands them.

#3 Do an initial inventory of all the equipment needing to be maintained –

You should a complete inventory of all of the equipment that will be part of your plan.

#4 Make decisions on the plan you wanting to follow –

Make final decisions on how the plan will be carried out.

#5 Read through all of the equipment manuals –

It is important to know as much about the machinery as you possibly can before you get started.

#6 Schedule long-term maintenance plan –

Set up a long-term maintenance plan that covers all of the vital systems of the equipment.

#7 Schedule short-term maintenance plan –

Set up a short-term plan that covers a more basic look over of the system.

#8 Train your people –

Before you set your plans in motion you want to be sure that all of your people are all on the same page and ready to carry out the mission.

For some medical facilities this type of maintenance on each piece of equipment requires a special department within the organization. For others it is more cost effective to outsource medical equipment maintenance and repairs to a company that specializes in the repair of medical equipment and parts needed for complex repairs on large scaled equipment such as linear accelerators, CT scanners, and a variety of radiation oncology equipment.

When Is It Time to Replace Your LINAC System Instead of Repairing It?

It is a known fact that linear accelerators, LINAC systems are expensive. Not only is the piece of equipment on a whole costly but also buying the replacement parts for linear accelerators can be quite costly, especially if it is a rush order. Hence, regular maintenance and care must be ensured to enhance its lifespan.

The importance of a LINAC system for a healthcare facility provider that offers cancer treatment is known to one and all. This intelligent system is designed to treat cancerous cells and kill them as part of cancer treatment. Therefore, it is considered to be a vital aspect in the treatment of different type of cancers.

Health experts know that the radiation that emits out of LINAC and other such devices also pose certain health hazards. However, linear accelerators boast of advanced safety measures; hence, these machines are programmed to provide only the required dosage that is required keeping in consideration the condition of the patient.

The problem with LINACS, like other systems, they can start to falter over time. Regular use can lead to damages in different parts of the machine, as a result, it may start showing deteriorate signs or stop working completely. A tough decision to make here is whether to get it repaired or if the equipment needs to be replaced.

The key is to know when to fix or when to replace. When equipment starts to falter on a regular basis, it may be time to look into finding a refurbished LINAC system. However, a system that is just experiencing normal wear and tear should be repaired using linear accelerator replacement parts.

You should consider the replacement option in case a part of the system has faltered or stopped working when it starts to occur on a regular basis. However, in a situation where a single part of the system stops, or something occurs that is normal it is a better option to repair the equipment. These large pieces of medical equipment are meant to withstand time so in many cases repair is the best options.

It really comes down to a number of factors such as downtime from the present equipment. If you are continually experiencing equipment failure that leads to cancelled treatments then you may have to analyze the cost between patient care, cancelled appointments, repair expenses, replacement parts, vs the cost of new equipment.