Prof. Bijlenga presented several cases including Arteriovenous Malformation (AVM) and brain tumor removal, showing how navigation with an Augmented Reality neurosurgical microscope can allow to better understand anatomical structures and how this assistance opens up new possibilities for neurosurgeons.
He uses the Leica M530 OHX surgical microscope, a precision microscope for neurosurgery and other complex procedures. Equipped with the groundbreaking FusionOptics technology, it unites an enhanced depth of field with high resolution to create an optimal view of the surgical field. The microscope integrates both the Brainlab Microscope Navigation software and the GLOW800 Augmented Reality fluorescence for Fluorescence Guided Surgery (FGS).
Fluorescence in neurosurgery offers critical information. In the case of an AVM removal for example, it can help preserve small en-passant vessels, which can be difficult to visualize and preserve otherwise according to Prof. Bijlenga.
Discover the video of his presentation below, as well as a full transcript. For more information on neurosurgery operating microscopes, contact a Leica representative. Our team will be happy to advise you on different options including the Leica M530 OHX microscope as well as the ARveo digital Augmented Reality neurosurgery operating microscope. The ARveo microscope from Leica Microsystems provides a single, precise and augmented view of the surgical field in real time. Both the M530 OHX and the ARveo are compatible with Brainlab navigation.
“I’m Professor Bijlenga, I work in Geneva University Hospitals as a neurosurgeon. I spent the last 5-6 years working on improving navigation systems using microscopes. Today I will present microscope-enhanced navigation. What I will present is an overview of a method we use.
Augmented Reality Skin Surface Registration
[01:12 - 01:45]
The concept is actually to use the microscope to register. And you can use the microscope to register using the face of the patient, to have kind of a first alignment. Here, you can use the eyebrow, the nose, the ear, which gives you access. So, you can actually see if your navigation is shifted or if it’s rotated. And there is a way now to digitally correct that, manually, interacting with the navigation, to re-register.
Augmented Reality Bone Registration Landmarks
[01:46 - 03:00]
Then, what you can do is when you open the skin, you can expose bone, and on the bone, there are lots of landmarks. There are sutures, there are diploic veins, going through holes, there are special bumps and hills and valleys that you can follow. In blue here are the usual landmarks we use to actually make a very precise registration of the navigation, meaning that on the imaging we recognize those features and, on the patients, we recognize the same features, and realign the navigation according to those features.
Now, this is for the outside but when you open the skull, you still have bone inside. And here again there are classical features you can use to re-register. Classically, you will have here the sphenoid ridge, which you can be drilling and you can readjust. You will have here most probably the meningeal artery groove, which you can find. And in the posterior fossa, you can have the internal auditory canal for example.
Augmented Reality Signature Vessel Registration
[03:01 - 03:58]
Then, once you have access to the brain itself, the brain is full of vessels. And here is actually the concept that you can recognize vessels, and each vessel has bifurcation which has a very typical and unique shape. You can take advantage of that shape to actually register using signature structures. So here is the concept that you have the image you see: on the right side you have the digital image reconstruction of the vessel and you can see that there is here a Y shape which is the same. This is the signature structure you can register. The idea is to make an edge detection and to get in the future a computer doing that for you, so that the computer recognizes those different shapes all around your surgical paths and can link to it and readjust the navigation according to those landmarks.
Augmented Reality Signature Structures: Cortex – Tumor
[03:59 - 04:43]
Now, when you open the brain, you’re facing the cortex and the white matter and maybe the tumor. And you can see that there are differences in gray shades and actually those difference in gray shapes are very similar to what you can see on imaging, on T2 images or on different types of images. You can see that there is a shape and this shape is very similar to what you see in the operating field. And again, you can use those characters, shapes, to actually re-register at the millimetric level. Here there’s the cortex and here there’s some tumor. And you can see that you can map those two things.
Augmented Reality Signature Structures: Ventricles
[04:44 - 05:07]
If you go deeper, you end up with the ventricles. The ventricles are easy cavities to segment, so the blue image here is quite easy to obtain and when you open here the ventricle, you can see if your virtual ventricle is actually well adjusted with the real ventricle.
Augmented Reality Signature Structures: Fluorescence
[05:08 - 06:04]
This is an example of an AVM (Arteriovenous Malformation) where you can see the vessels of the AVM using GLOW800. You can have MID images of the image that was acquired prior to the operation and you can see that the green and the white here overlap quite well. The idea here again is to have a computer adjusting that, so that you have automatic tracking continuously during the operation.
Inside, when you operate on tumors, you can use