Recently, researchers from India have developed a 3D printed mechanical system that helps to counteract the movement of breathing when administering targeted radiation for lung cancer. What challenges does body movement present, what did the researchers develop, and how can such systems improve future medical procedures?

What challenges does movement present during medical treatment?

When administering tests and treatments to patients, it is generally required for patients to remain still. Many tests need patients to stay still as movement can either produce unclear results (when using imaging systems) or interfere with the results (such as ECGs). The need to remain still is even more critical during sample taking from blood to biopsies as there is an increased risk of damage from the protrusion by needles or medical equipment.

But treatments can also require a patient to remain still. For example, targeted radiation treatments for cancer take advantage of a high energy particle beam to destroy cancerous cells, but the beam does not distinguish between healthy and cancerous cells. As such, the beam needs to be held steady and directed towards the cancerous tissue. Any movement can change the target location of the beam.

Attempting to account for unpredictable movement can be challenging, and some applications may not even use such equipment. For example, MRI requires a patient to remain very still during scans, but electronic equipment cannot be present near the system due to the destructive force of the magnetic fields generated by the MRI.

Researchers develop a 3D printed system to counteract motion

Recently, researchers from India have developed a 3D printed system that can simulate a patient's breathing pattern. Called a phantom, the system is modelled after a patient. Its simulated breathing motion copies that of the patient. From there, the phantom is placed into a CT scanner and targeted particle beam to determine how effective the beam is at targeting a specific point.

The data gathered from this stage further allows researchers to modify better and manipulate the particle beam to stay focused on cancerous tissue. Thus, the use of the phantom can help minimise damage to healthy tissue and reduce the risk of secondary cancers forming as a result of radiation exposure.

How can phantom models of patients help doctors in the future?

The use of phantoms that resemble each patient undergoing treatment allows doctors to run tests and trials before committing to patient care. In the case of the lung phantom developed by researchers from India, lung cancer patients can breathe more easily during targeted beam therapy and reduce the risk of damage to healthy tissue.

Furthermore, phantoms are not too dissimilar to digital twins in industrial applications, whereby an industrial process is converted into a virtual digital system that can be experimented with. Thus, phantoms can help doctors maximise the effectiveness of specific treatments that are vulnerable to movement.

The use of 3D printing technology also helps reduce the cost of modelling patient data, which avoids the need for advanced real-time surface mapping of the patient, close-loop feedback systems to move the bed in real-time, or advanced robotic kinematic systems. A patient can be monitored for a minute or two to measure their breathing pattern, and then in a few hours, a perfect replica of their breathing is developed, which can then be used in a CT scan to confirm the results of beam therapy.