As reported in Device, a team of biomechanical engineers and surgeons has developed a 3D-printing soft robot that can accurately deliver hydrogels to the vocal cord surgical site to reconstruct tissues removed during surgery. The robot’s printhead is only 2.7 mm in size—the smallest bioprinter reported to date.

“Our device is designed not only for accuracy and printing quality but also for surgeon usability,” says first author and biomedical engineer Swen Groen of McGill University. “Its compact and flexible design integrates with standard surgical workflows and provides real-time manual control in a restricted work environment.”

Between 3% and 9% of people develop voice disorders during their lifetime due to cysts, growths, or cancers on the vocal cords. These growths are usually removed surgically, but many patients develop fibrosis post-surgery, which stiffens the vocal cords and makes speaking difficult. To prevent fibrosis, surgeons usually inject hydrogels into the throat tissues, but it’s difficult to deliver hydrogels accurately via injection.