MIT’s robotic thread could weave through human brain to remove blood clots
What is a stroke? Stroke is a medical emergency which occurs due to the interrupted or reduced blood supply to the part of the brain. It may occur due to the blockage of an artery or even leakage of the blood vessel. It has symptoms like headache, trouble with walking talking, or also seeing, paralysis of the arm, leg or face.
Xuanhe Zhao, an associate professor of mechanical and of civil and environmental engineering at MIT, explains that in the United States, stroke is the leading cause of disability. If within the first 90 minutes, acute strokes are treated, then the survival rates of the patients could significantly increase. Thus, they are hoping to design a device that can reverse the blood vessel blockage within this ‘golden hour’.
Yoonho Kim, who is a graduate student in MIT’s Department of Mechanical Engineering says that this procedure would require surgeons, who must be specially trained for this task and who can cope with the repeated radiation exposure from fluoroscopy. Further, he added that this skill is demanding and there are not enough surgeons for the patients in rural areas.
The good news is that MIT engineers have now made proficiency in both hydrogels (biocompatible materials which are made mostly of water and a 3-D printed magnetically- active materials). They are intended to jump, crawl or even catch a ball by following the magnet’s direction.
Thus, the researchers combined their work in hydrogels and in magnetically activated materials to produce a threadlike robot which can actively slide through the narrow pathways such as Labyrinthine Vasculature of the brain. This thread-like robot can go in specified directions through the tiny blood vessels of the human brain by breaking up the blood clots and restoring the blood flow. It is being said that it is one of the better and less invasive methods than the previous methods of brain surgery, but it requires a skilled surgeon who can manually guide the wire.
The core of the robotic thread is made from a nickel-titanium alloy (a bendy and flexible material). This nickel-titanium alloy or nitinol wire returns to its original shape. The material is also bonded with hydrogel. Then some comparisons were made between the robotic thread coated versus uncoated with hydrogel. And it was that the hydrogel gave the slippery advantage without getting stuck.
“Navigating through the blood vessels in the brain which has a very small diameter, has been a challenge in surgery”, says Kyujin Cho, a professor of mechanical engineering at Seoul National University. But with the help of this research, some potential is shown to overcome this challenge and surgical procedures in the brain are possible without open surgery”.
Now one question arises that how surgeons can be kept radiation-free from this new robotic thread? Well, Kim says that a magnetically directed guidewire gets rid of the need for surgeons to physically push a wire through the patient’s blood vessels. This implies that there is no need for the surgeons to be close to the patient, and most importantly, the radiation generating fluoroscope.
Younho Kim, who is the lead author on the study, says that “magnetic field and the fluoroscopy procedure can be applied by existing platforms at the same time to the patient. Even, there is no necessity for the doctor to be in the same room; he could be even in a different city too, controlling the magnetic field with a joystick. Our hope is using the maximum advantage of the existing technology to test our robotic thread.”
The team’s research was published in the journal Science Robotics