Tag Archives: prosthetic

3D Printing Enables Complex Vascular Networks for Prosthetic Applications

Posted on by
Reply

Vascular networks crafted by computational models

Andrew Brodhead

Computational models enabling the swift design of vascular networks for 3D-printed organs could advance the prospect of artificial liver, kidney, or heart transplants, eliminating the dependency on donors.

Individuals suffering from organ failure often require transplants. Merely 10% of the global transplant demand is currently met. In response, researchers are innovating techniques to produce lab-grown organs via 3D printing. However, these efforts hinge on experimental methodologies for sustaining the vascular networks long enough to remain viable for days or weeks.

To tackle this issue, Allison Marsden from Stanford University and her team have developed a computational model that facilitates the design of these networks for any organ using mathematical principles explaining how blood vessels branch within the body.

They evaluated their method by creating a network of 25 vessels with 1 cm wide ring-shaped structures that were 3D printed from kidney cells according to their design.

The team then fabricated the vascular network into rings using cold gelatin particles, subsequently heated to 37°C (98.6°F) to dissolve the gelatin, resulting in a network of hollow channels measuring 1 mm in width that mirrored blood vessels. The researchers continued to circulate oxygen and nutrient solutions through the channels to replicate normal blood flow.

After one week, the ring contained approximately 400 times more viable cells compared to a similar ring made from bloodless kidney cells that had been exposed to blood-like fluids.

“We succeeded in keeping the cells near the network alive,” remarks Marsden. “However, the more distant cells perished because we were unable to print the smaller, more intricately branched networks necessary to deliver nutrients to those regions. Our team is actively seeking solutions to this challenge.”

“They are definitely pushing the limits of feasibility,” states Hugues Talbot from University Paris-Clay, France. This novel approach might someday enable scientists to design vascular networks for full-sized organs in mere hours, rather than days or weeks. “Networks designed in this manner could potentially substitute or at least complement lab-grown organs in the future.”

First, researchers must devise methods for 3D printing these vascular networks onto larger organs. If progress continues on this path, Marsden expresses a desire to experiment with 3D-printed organs in pigs within the next five years.

Topic:

Source: www.newscientist.com

Artificial Intelligence creates personalized 3D printed prosthetic eyes

Posted on by
Reply

A man with artificial eyes not made by AI

Stephen Bell, Ocupeye Ltd.

Prosthetic eyes designed with artificial intelligence and 3D printing could benefit more people by requiring 80% less time for human experts compared to traditional manufacturing methods. Small trials also suggest that this approach leads to adequate prostheses in most cases.

For example, in the UK, Approximately 1 in 1,000 people wears a prosthetic eye., it takes a highly trained ophthalmologist to take an impression of the eye socket. Many people wearing such prostheses also have orbital implants that replace lost eye volume and create a surface to which muscles can be reattached, allowing natural eye movement. Masu. A prosthesis is placed over this to give it a natural appearance.

The standard process for making a prosthetic limb takes about eight hours; Johan Reinhardt Researchers at the Fraunhofer Institute for Computer Graphics in Darmstadt, Germany, have developed a method to automatically design and 3D print an implant that fits into a wearer's eye socket and aesthetically matches the remaining eye. .

“It's more comfortable to do an optical scan than to have someone pour this alginate.” [mould-making material] It seems difficult to make an impression on the eye socket, especially for children. [sit through] This is the procedure,” Reinhardt said.

In the new process, an optical coherence tomography scanner uses light to create a 3D model of a person's missing eye, so the back of the prosthesis can be designed to fit snugly. A color image of the remaining eye is also taken to ensure an aesthetic match.

The data is collected into an AI model, a design is created, and then 3D printed on a machine that can operate at a resolution of 18 billion droplets per cubic centimeter.

Once the prosthesis is printed, a human eye doctor can polish and adjust it for the perfect fit. This task takes only 20% of the time of the existing process.

3D printed prosthetic eye designed by AI

Johann Reinhardt, Fraunhofer IGD

In a trial of 10 people at Moorfields Eye Hospital in London, only two people found these prostheses did not fit properly. Neither has orbital implants, which Reinhardt says poses problems for scanners and AI designers.

The team hopes to improve the process to significantly reduce the cost required to create convincing prosthetics and make them available to more people. However, Reinhardt says it is unlikely that future prosthetics will be created without human experts.

“We think of this like a tool for ophthalmologists,” he says. “So this is not going to replace an eye doctor, but it's a new process that they can use, and we think it's going to give them better results in terms of appearance.”

topic:

Source: www.newscientist.com

Prosthetic leg sensitivity triggers feeling of hot and cold in amputated hand

Posted on by
Reply

Fabrizio Fidati tests temperature-sensitive prosthetic arm

EPFL Cahiers

A man who had his right arm amputated below the elbow can now feel heat and cold in his missing hand through an improved prosthetic hand equipped with a heat sensor.

After amputation, some people may still have a sense of touch or pain in the missing arm or leg, known as a phantom limb. In some cases, these sensations may be caused by nerve endings in the remaining upper limbs.

This prosthetic hand works by applying heat or cold to specific areas of the skin on the upper arm, inducing a thermal sensation in the phantom hand.

“Previous studies have shown that these spots are present in the majority of amputee patients we treat,” he says. Solaiman Shokur at the Swiss Federal Institute of Technology in Lausanne.

First, Shokur and his colleagues mapped spots on study participant Fabrizio Fidati's upper arm that triggered sensations in different parts of the phantom hand. They then outfitted his existing prosthetic arm and socket with a sensor and device called a thermodes that can make it hot or cold.

Tests showed that Fidati was able to identify hot, cold, or ambient temperature bottles with 100% accuracy by touching the bottle with the modified prosthesis. When the thermal sensors in his prosthetic limbs went off, his accuracy dropped to a third of his.

The prosthetic hand also allowed Fidati to distinguish between glass, copper, and plastic by touch, while blindfolded, with just over two-thirds of the accuracy of his uninjured left hand.

In another recently published study, Shokur and his colleagues showed that amputees use temperature-sensitive prostheses. Can detect whether an object is wet or dry.

“We were able to give amputees the sensation of moisture, and they were able to detect different levels of moisture, just like a healthy hand,” Shokul says.

Omid Kabehei Researchers at Australia's University of Sydney say their work could one day have applications beyond prosthetic limbs, such as giving robots a wider range of bodily sensations.

“This is very important work,” he says. But he cautions that this is not a clinical trial and questions how well the technology will work in the real world, where warm and cold climates are extremely different.

“We would like to see how this device performs in a hot and humid place like Singapore,” says Kavehei.

topic:

Source: www.newscientist.com