Can Doctors 3D Print Inside The Human Body Without Making A Cut?

Even with modern medical advancements like robotic arms and keyhole procedures, fixing internal medical problems still requires cutting into the human body. However, a team of researchers at Caltech is working on a completely different approach that skips the scalpel entirely. They’re currently testing a method to 3D print solid medical treatments directly inside a living creature.

By using targeted sound waves instead of sharp instruments, the engineering team has successfully solidified injected liquid materials deep within mice and rabbits. The million-dollar question is, would doctors eventually be able to build custom drug-delivery gels or seal internal wounds without making a single physical incision?

How Does Ultrasound Printing Actually Work?

In the past, scientists tried using infrared light to harden liquid materials inside the body, but this approach was highly limited because light only penetrates just below the surface of the skin. To get around this problem, a Caltech engineering team guided by professor Wei Gao turned to ultrasound since sound waves can easily travel right through thick layers of tissue and bone.

The actual procedure starts by injecting a specialised liquid into the patient that’s filled with microscopic fat capsules holding a setting agent. When focused ultrasound waves hit the exact target area, the local temperature rises by just a few degrees. Consequently, these tiny capsules melt and release their contents to instantly harden the liquid into a solid custom structure exactly where the doctor needs it.

What This Could Mean For Targeted Drug Delivery

Treating illnesses like cancer often requires flooding the entire system with harsh medications. On the contrary, this acoustic printing method allows doctors to trap drugs inside a printed gel right at the source of the problem.

During its studies, the research team was able to successfully print a chemotherapy-loaded gel directly onto a bladder tumour in a mouse. As a result, the structure stayed securely in place and slowly released the medication over several days. This hyper-localised approach killed significantly more cancer cells compared to a standard liquid injection, which often washes away before doing its job.

Can Printed Materials Help Seal Internal Wounds?

Beyond just delivering drugs, this technology is capable of creating biological adhesives to fix internal injuries. During one of its experiments, the engineering team used this sound-wave technique to patch up a punctured goat heart by injecting the bioink and applying an ultrasound wand through thick layers of tissue to cure the material.

Because the resulting patch formed a tight and flexible seal that moved naturally with the beating organ, medical professionals might not need to perform open-chest surgery to successfully close internal ruptures in the future.

Challenges Of Using A Living Printing Bed

While the science is promising, it’s undeniable that a living body isn’t a still surface. We must bear in mind that internal organs naturally breathe, pump and twitch. Because of this constant movement, keeping sound waves locked onto a microscopic target is quite difficult and the printed shape could easily form incorrectly if the tissue shifts during the procedure.

However, researchers believe that artificial intelligence could solve this issue by training algorithms to track organ movements in real time, which would allow the ultrasound equipment to autonomously adjust its focus to match the patient’s natural rhythms. Luckily, the bioink also contains tiny gas bubbles that show up clearly on medical monitors so doctors can actually watch the structure forming live.

When Will We See This in Hospitals?

So, could doctors actually end up printing materials inside your body without opening it? While this non-invasive technology isn’t happening in local hospitals just yet, the verified proof-of-concept is currently seeing significant success in pre-clinical animal testing. At the moment, hospitals only use 3D printing externally to create things like anatomical models or custom implants that still require traditional surgical insertion.

On the other hand, experts estimate that early human trials for this acoustic method could begin in the next three to five years if studies on larger animals continue to show positive results. Because of this, the concept of a patient acting as their own personalised manufacturing environment is rapidly moving from a theoretical idea into a clinical reality.

In terms of treating complex internal conditions, injecting a smart liquid and using sound waves to build custom biological patches right where they belong proves that invasive surgery won’t always be the solution in the future.