InSight Surgical Technologies
Updating the Map as the Brain Shifts

A neurosurgeon can begin an operation with an image that precisely captures the patient’s anatomy. As surgery progresses, however, the brain can deform, shift and change shape, creating a gap between the original image and the anatomy in front of the surgeon. When the map no longer matches the brain, navigation becomes less useful.

“So that’s what we’re doing in surgery. We’re updating the map,” says Keith D. Paulsen, PhD, co-founder, board director, president & Chief Executive Officer.

InSight Surgical Technologies is developing surgical guidance around that problem. Its lead I²UPDATE system is designed to account for brain deformation during surgery, while its quantitative fluorescence technology addresses signals that may not be visible to the human eye.

Moving Beyond Static Navigation

Conventional navigation relies on preoperative imaging registered to the patient at the beginning of surgery. That registration can be highly accurate initially, but the anatomy changes once the cranium is opened and tissue is removed. Swelling, sagging and tissue removal can make the original map less representative of the surgical field.

Paulsen notes that conventional navigation may begin with registration accuracy of around two millimeters, while brain movement during a procedure can sometimes reach a centimeter or more.

I²UPDATE updates the map during the procedure. Stereovision cameras mounted on the surgical microscope capture the changing surgical surface. A three-dimensional computational model uses that information to estimate deformation throughout the brain and update the surgical images.

The work builds on decades of research. Paulsen and co-founder David Roberts began thinking about brain shift in the late 1980s, when the computational resources and algorithms needed to address the problem were less mature. Earlier research showed that intraoperative updating could work, but skilled people in the operating room still had to make decisions for the algorithms.

Turning that research into a commercial system required codifying those human decisions. InSight studied what skilled researchers were doing when processing intraoperative images and worked to translate those decisions into algorithms. The result is an autonomous, on-demand workflow in which the surgeon requests an update, the system collects the required data and produces updated guidance.

I² UPDATE is the company’s primary commercial focus. Its quantitative fluorescence, or QF, imaging provides a complementary capability by addressing signals that may not be visible to the human eye.

The technology quantifies fluorescence and can distinguish multiple fluorophores, separating signals that might otherwise blend together. Paulsen describes cases in which a surgeon believed a resection was complete, but the camera detected fluorescence that was not visible to the eye. Biopsy later confirmed tumor in the tissue.

From Multiple Data Streams to Autonomy

InSight is exploring how other information could enter the same framework. Ultrasound could provide subsurface information alongside stereo vision, while fluorescence could add another layer of disease information. The longer-term goal is to bring these data streams into a common, co-registered navigation space.

The company envisions extracting useful features from an ultrasound sweep without requiring surgeons to interpret difficult ultrasound imagery themselves. Those features could enter the deformation-estimation pipeline and return information in the MRI or navigation format surgeons already use.

AI could play a larger role as that foundation develops. Paulsen says InSight currently uses AI selectively because of regulatory considerations and limited archived intraoperative surgical data, while deterministic image processing handles certain tasks.

For now, the commercial focus remains I² UPDATE 1.0 and neurosurgery. Rather than waiting for stereo vision, ultrasound, fluorescence and every future capability to work together, InSight is commercializing a focused autonomous product and building from this foundation.

That focus has earned InSight Surgical Technologies recognition as one of the Top Emerging Autonomous Surgical Navigation Systems 2026.