Dr. Daniel Cho, assistant professor in the Division of Plastic Surgery, received a patent earlier this year for an implantable device that can monitor intracranial pressure (ICP). The device can be used for long-term monitoring of infants with craniosynostosis, a serious birth defect that is caused by one or more bones of the skull fusing too early. The condition leads to abnormal skull development and restricts the growing brain. If left untreated, craniosynostosis can result in developmental and cognitive delays, seizures, blindness, or even death.
Craniosynostosis can be corrected through surgery, but patients need to be followed closely to ensure ICP does not build up in the skull as the child grows. Dr. Cho, who specializes in the treatment of infants and children with craniofacial differences, developed CranioCheck so ICP can be monitored in these children, eliminating the diagnostic ambiguity or the need for invasive ICP monitoring procedures.
Before CranioCheck, standard methods for evaluating ICP included an unreliable eye exam or a highly invasive surgical procedure. To fix this problem, Dr. Cho combined his experience as a surgeon and his PhD in Biotechnology with a focus in polymer chemistry to develop a tiny device that can be placed during the initial corrective surgery for craniosynostosis and then monitored over time via x-ray.
CranioCheck works without any electronics or battery: a small radiopaque marker embedded in the device deforms in response to changes in ICP. Because the marker is visible on a standard x-ray, a child’s ICP can be measured at any local radiology facility with a quick, non-invasive plain x-ray — no additional surgery is required. This approach provides significantly more accurate and quantitative measurements of ICP than eye exams, and avoids the risks and costs of repeat invasive surgical monitoring.
To design the device, Dr. Cho partnered with undergraduate students in the biomedical engineering program in the UW–Madison College of Engineering. Working closely with Dr. Cho over the course of three semesters, the students designed the device as a part of a capstone project through the Biomedical Engineering Design (BME Design) program. Upon the completion of the capstone project, Dr. Cho worked with the Wisconsin Alumni Research Foundation (WARF) to file a patent for CranioCheck. WARF is the designated patenting and licensing organization for the UW-Madison, helping researchers bring transformative discoveries to the commercial marketplace.
After successfully testing this device outside of living organisms under highly controlled conditions in the lab, Dr. Cho’s lab moved on to testing the device in living organisms to assess its safety, efficacy and biocompatibility. Dr. Jasmine Craig, a plastic surgery resident, helped test the use of CranioCheck in a rabbit model. The promising results of the study gained national attention when Dr. Craig and Nada Botros, a research fellow in Cho’s Craniofacial Research and Innovation Lab and medical student at the Medical College of Wisconsin, presented their findings at Plastic Surgery The Meeting 2025 and won the American Society of Plastic Surgeons Inventors Challenge.
Beyond its clinical precision, CranioCheck has the potential to meaningfully expand access to care for families across Wisconsin and beyond. Children with craniosynostosis require long-term follow-up to monitor ICP, often at large academic medical centers that may be hours from home. Dr. Cho, who runs a craniofacial outreach clinic in Green Bay, sees firsthand the burden this places on families, including travel costs, missed work, and the stress of repeated trips to a tertiary care center. Because CranioCheck readings require only a plain x-ray, families could have routine ICP monitoring performed at a local hospital or imaging center, reserving travel to a specialist only when results warrant it.
The device also enables on-demand measurement: when a child develops new symptoms such as headaches or changes in school performance, a single local x-ray can provide a concrete ICP value, which is far preferable to the current alternative of an invasive, hospital-based monitoring procedure. Dr. Cho’s vision is that CranioCheck will reduce financial and logistical barriers for families while maintaining the highest standard of care.
“Seeing CranioCheck progress from an initial concept to a patented device has been an incredible journey,” Dr. Cho said. “Collaborating with undergraduate students through BME Design to build the first prototype, partnering with WARF to secure the patent, and then mentoring medical students and graduate students through early preclinical testing has reminded me just how powerful the collaborative spirit at UW–Madison truly is.”
“There is still a great deal of work ahead before CranioCheck is ready for patients, but I am confident that this institution — and the people in it — give us the best possible foundation to get there,” Dr. Cho continued. “CranioCheck is a testament to what becomes possible when faculty, students, and research partners work together toward a shared goal, and I think it is a meaningful example of the Wisconsin Idea in action — using the resources of this university to develop innovations that can improve lives far beyond our campus.”
If you are interested in working on a project like this with Biomedical Engineering students, please feel free to submit your project idea here.