Thanks to a partnership between a surgeon and NASA’s Jet Propulsion Laboratory (JPL), a new camera system could improve minimally invasive surgeries and provide 3D endoscopic images of the brain.
In a traditional open-brain surgery, a section of the skull is taken out so that a medical practitioner can access the area. The craniotomy process is costly, however, and requires a lengthy recovery time for patients.
Endoscopic brain surgeries are less invasive. Instead of having to take apart the skull, a medical imaging device called an endoscope is placed inside of the patient; the instrument’s lens system sends its imagery to a display screen that a surgeon can monitor.
The two-dimensional, high-resolution endoscopic process enables shorter hospitalization times and quicker procedures, however, the technology does not provide depth perception, an important capability as doctors navigate sensitive areas of the brain.
A new endoscopic instrument, developed by NASA’s Jet Propulsion Laboratory and Dr. Hrayr Shahinian, a surgeon and medical director at the Los Angeles, CA-based Skull Base Institute, features a 4-mm camera that transmits high-resolution, three-dimensional images of an operating field to a display screen that a doctor views with 3D glasses.
The Multi Angle Rear Viewing Endoscopic tooL, or MARVEL, fits in a dime-sized hole made through the nose, nostril, eyebrow, or ear, potentially allowing surgeons to operate on the brain, using the system’s panoramic imagery as a guide.
Testing the Limits of Miniaturization
MARVEL’s development team is up against the physics of optics, faced with the challenge of how to provide high-definition 1080 ¥ 1080-pixel resolution and 3D imagery with a miniaturized device.
The 3D imaging camera uses a single lens plane, which has two “pupils” set in the back. An object can then be seen from two different perspectives and angles. The two images are transferred into an imaging plane, and the left and right images are overlapped in a time-multiplex manner, generating a valuable three-dimensional image for medical professionals.
“With the 3D surgery, the surgeon is going to be immersed. It’s almost like virtual reality,” said Shahinian, whose Skull Base Institute team has performed more than 5,000 endoscopic surgeries. “We’re going into the land of minimally, minimally invasive surgery.”
Aside from the challenge of creating three-dimensional images with such a tiny lens and sensor, the camera also had to be mounted in such a way that it could turn in a sweeping motion, a 120-degree arc from left to right. MARVEL’s camera bends and sweeps, providing surgeons with an important panoramic view of the operating field.
“Surgeons would like to be able to see behind a tumor or even sometimes look around the cavity to see if the tumor is extending into regions that are beyond the line of sight of a zero-degree endoscope,” said Harish Manohara, principal investigator of the MARVEL project at JPL. “You should be able to see if the tumor is too close to the sensitive nerves or surrounding area.”
As part of Phase 3, the final phase of collaboration, JPL will also design a customized imager that provides the appropriate resolution for clinical use.
Certain modifications will need to be made to the lab prototype design to achieve a higher definition and easier sweeping motion of the camera over the entire 120-degree arc.
The device must receive FDA approval before it can be used clinically.
Possibilities Beyond the Brain
The MARVEL camera has potential applications outside of the medical operating field as well, specifically in confined environments. Borescopes, for example, detect structural faults in machines or in components that cannot be easily accessed in a larger system. A 3D scope could be valuable to spot out-of-plane defects or faults, said Manohara. The device could even be used in space, he said, as teams receive close-up images of geological features in a confined environment.
Dr. Shahinian says that the technology will not be limited to brain surgery, and MARVEL could be used in other surgical fields, including neurology and orthopedics.
“I think it’s going to make surgery, as a whole, safer, more precise, faster, and it’s going to help ultimately millions of people across the globe,” said Shahinian.