The Science of Scatter Radiation and Lead Protection

How to Safely Lighten the Load on Our Most Vulnerable Caregivers
By Jonathan Yifat

Over the decades since the fluoroscope was first developed, we’ve been searching for better solutions to protect patients, doctors, and staff from the harmful radiation these devices generate. Some have been helpful, but often they protect only the operator, leaving other staff unprotected, or they protect only some parts of the body, leaving other parts exposed.

More recently, we’ve seen a great increase in the number and type of x-ray guided interventional procedures, including structural procedures in minimally invasive catheterization labs, as well as percutaneous coronary interventions (PCI) and cardiovascular implantable electronic devices (CIED). More procedures are taking place than ever before and some for extended periods of time, raising the radiation risk for doctors and staff (Korean Journal of Pain, 2022).

This pressing need to offer better protection for healthcare providers was the spark that led to the creation of Radiaction Medical and its device, a robotic plug-and-play accessory to C-arm systems, offering head-to-toe protection for everyone in the room. It’s been my privilege to add the scientific rigor and pragmatism from my physics background to the project, and to work closely with the caregivers who need this protection to ensure it seamlessly integrates into their existing workflows.

Other companies are also answering the call for better solutions, and in the scramble to bring effective devices to market, a notion has arisen that radiation blocking technology has reached a level where interventional teams can safely remove 100% of their lead shielding apparel. But while the whole industry is pursuing this goal, right now, even with an excellent radiation-blocking system in place, lead-based apparel still adds a valuable and necessary element of protection.

The real upside of newer, smarter technologies is that the protection they provide allows for game-changing reductions in the weight and bulk of traditional wearable shielding—up to 75%—without increasing the radiation risk. Such upgrades are long overdue, and the reality is that a modern approach with overlapping layers of protection can provide sufficient safety without obstructing workflow, something we owe everyone who enters a cath lab or other risky radiation environment to heal bodies and save lives.

Radiation dangers

The two main risks of scatter radiation in healthcare settings are the long-term damage it directly causes to the body and the musculoskeletal damage caused by wearing heavy protective clothing. Exposure for medical professionals can last for hours every workday, and this cumulative radiation damage increases the health risk for brain and breast tumors, cataracts, cognitive degradation, thyroid disease, and a range of serious concerns for developing fetuses. Fortunately, managing these risks is possible, and new technologies are making it easier.

Traditional wearable lead

Dense enough to block radiation but just practical enough to use as shielding apparel, lead has been our main radiation protection since X-ray imaging began in the late 1800s. In concept, a lead apron is a simple barrier between a radiation source and a human being at work. In practice, however, the drawbacks of lead-based apparel protection have become glaring over time.

While lead provides a barrier of protection to the torso and much of the upper leg, the rest of the body, including the head, neck, feet, hands, and face remain exposed to scatter radiation. The potential pain and debility caused by the sheer weight of protective clothing presents its own significant problems. Many cardiologists have left the field due to orthopedic injuries caused by this repetitive stress, which does not help to encourage young doctors to enter the specialty.

Moreover, regardless of weight or ergonomic design, no garment can offer 100% protection from scatter radiation. The gaps and seams that allow it to function also allow radiation to enter and reach the body. Even lead-lined head caps can do nothing to stop radiation from entering through the face and under the chin. Clearly, our best solution now is appropriate protective garments used in conjunction with other, modern radiation blocking technologies.

The foreseeable future of radiation protection

While fluoro-less technologies are under development, for the immediate term, X-ray fluoroscopy will continue to be a key component of image-guided procedures. The question is how best to protect the people using it. Currently, significant clinical evidence is not sufficient to support completely removing lead clothing, and existing health and safety laws continue to mandate its use.

Another concern is that, even with the latest full-room radiation blocking technology in place, situations can arise that reveal the unique value of wearable protection. Especially in cardiology, emergency complications can develop quickly, and the attending physician must have immediate patient access to render treatment, possibly even a full hands-on resuscitation. In these cases, any protective radiation barrier will simply be pushed aside. Only the doctors’ wearable protection will remain, and only if they were wearing it to begin with.

For electrophysiology procedures such as implanting pacemakers and defibrillators, the surgeon must be able to clearly see and touch the patient’s access area, so no protective barrier is possible. Wearable lead is a must in these situations, but in combination with newer blocking technologies, it need not be dangerously heavy or obtrusive.

While new and different approaches are beginning to appear, for the most part, they are new takes on old solutions. In most cases, we’re still just placing a shield between people and the x-ray source. How artfully this is accomplished makes all the difference.

For example, Radiaction’s technology blocks scatter radiation at its source, reducing exposure to the operating room by an average of 92% and to the treating physician’s head, neck, and face by up to 97%. This full-body protection surpasses current lead shielding performance without compromising safety, functionality, workflow, image quality, or patient access. Radiaction preclinical studies provide compelling evidence that it may be possible to safely reduce worn lead by up to 75% with the Radiaction System, potentially saving the wearer an estimated 15 pounds, while still providing protection during clinical emergencies when shielding barriers cannot be used. We will continue to study this opportunity clinically and bring this data to market.

While some radiation blockers work well enough to justify reducing protective apparel, no current technology can eliminate the need for it entirely. Nevertheless, life-changing improvements to workflow efficiency and orthopedic health are possible simply by reducing the weight and bulk of this equipment. Our quest is to find sophisticated solutions to these problems, minimizing inconvenience and discomfort while providing a very high level of protection for everyone in the room.

Someday, wearable radiation protection may be rendered quaint and no longer necessary, and no one will cheer louder than me. But my enthusiasm will be grounded not in wishful thinking but in the reliable clinical data our healthcare teams need and deserve. Until then, the data demands we continue with wearable protection. Mercifully, our data shows a trend toward the lightest and easiest protective apparel we’ve ever had.

Jonathan Yifat is CEO of Radiaction Medical.

 

References

  1.  NLM or the National Institutes of Health. Korean J Pain. 2022 Apr 1; 35(2): 129–139

 

Sidebar

A View from the Cath Lab
by Mohammad Sahebjalal, MD

People in my field are waking up to what’s been going on with scatter radiation in interventional cardiology labs, and not a minute too soon. Our base of expertise has been draining away through illness, injury, death, and retirement decades early because they can’t tolerate working in heavy gear or where the radiation risk is high. We know the older generation has had too much exposure, and that must end before it repeats. But changing entrenched habits can be difficult, even for good reasons.

I’ve found it helps to get colleagues thinking differently about the source of danger. Many incorrectly believe it is limited to whatever is directly in the path of the C-arm’s x-ray emitter. The real danger, however, is from the scatter radiation that bounces willy-nilly around the room after leaving the emitter. It can hit you from any direction, and it’s an active threat as long as the fluoroscope is running.

While necessary, lead aprons and other protective gear can leave the head, eyes, hands, and lower extremities without much protection. Most of the DNA damage that can cause cancers occurs in these exposed parts. Scatter radiation often enters through the chin heading upward, and there’s nothing to stop it from damaging the brain.

This is why a combination of protective systems makes the most sense, ideally, an automated shielding system to protect everyone in the room, augmented by spot-shielding in sensitive areas, and protective apparel for individuals. With overlapping systems reducing scatter radiation generally, the weight and thickness of lead apparel can be reduced so it can be worn safely and comfortably for typical tours in the cath lab.