Augmented and Virtual Reality Escalate LVHN’s Expanded Skull Base Surgery Program

Lehigh Valley Health Network (LVHN) is serious about its skull base surgery program. So much so, it has recruited surgeons from some of the country’s top health centers to expand its multidisciplinary team. Part of both Lehigh Valley Fleming Neuroscience Institute and Lehigh Valley Institute for Surgical Excellence, these experts closely collaborate to care for people with conditions such as acoustic neuromas, those affecting the nerves supplying the inner ear, and anterior pituitary tumors. 

While those are two of the most common conditions treated, the entire realm of skull base disorders is within this team’s expertise. Because the skull base is a superhighway of bone structures, blood vessels and nerves, neurosurgeons, otolaryngologists and neurotologists confer and work alongside each other on just about every case. In recent years, their work was further enhanced with the advent of augmented reality (AR) and virtual reality (VR) to help visualize these crowded and obscure parts of the human anatomy.

By definition, AR involves overlaying simulated digital imagery with the real world as seen through a camera or heads-up display. When the user mixes digital imagery with real surroundings, the process is sometimes called “mixed reality.” VR is a virtual experience usually requiring a headset. The user’s view is replaced by a simulated, immersive and interactive virtual environment. When used in surgery, AR and VR imagery is magnified as much as 20 times bigger than life.

Walter Jean, MD, Chief, Division of Neurological Surgery, LVHN, and an integral part of the Neuroscience Institute and the skull base surgery program, has been using AR and VR for more than five years. He and the team apply the technology to preplan delicate surgeries and to conduct those surgeries as well. The image used is taken from radiology: a thin-cut computed tomography angiogram, an MRI scan and a digital subtraction angiography, which shows only the blood vessels. The team can then import the data from these three different modalities into the virtual reality platform (Surgical Theater®), which fuses them into one single, unique image. This gives the team a highly-detailed, three-dimensional look at a person’s anatomy both before and during a surgical procedure.

“The advantage of VR is that we not only have the ability to see and appreciate a three-dimensional view of the patient’s brain and anatomy, but also the pathology,” Dr. Jean says. “Then we can examine the pathology we’re dealing with – an arteriovenous malformation, an aneurysm, a tumor – and see its relationship both to the blood vessels and to the brain substance itself.”

He explains that, for planning surgery, the team can rotate the 3D view. Wearing goggles, as if viewing a video game, the surgeons can look around the entire brain including the blood vessels, surrounding tissue and bone. In a sense, it’s simulating the entire surgical procedure beforehand so that when they get to surgery it’s not a surprise.

“It’s as if we can perform the surgery in the office before the actual operation, and we can do that as many times as we want to,” Dr. Jean says.

This visibility also allows the surgeons to realistically consider various surgical approaches. For example, the team may have planned an endoscopic endonasal approach and a contralateral transmaxillary approach to access a tumor. However, imaging could show that the paraclival carotid artery was blocking the superior portion of the tumor from these approaches. So, they could have to replan accordingly. 

These advances in computer technology and imaging mean surgeons can operate deep in the brain stem through safe trajectories, magnify everything by 20 times with the microscope and take out abnormalities through an opening 1-2 millimeters in diameter. This makes surgery not only far less complicated for surgeons, but also safer for patients.