EBME & Clinical Engineering Articles

Whether clipping an aneurysm, performing a microvascular decompression or a bypass, the surgeon’s ability to clearly view and assess anatomy and blood flow is critical for an optimal outcome.

Augmented reality technology enables more accurate surgery. Augmented reality imaging technologies can supplement the usual microscope view, in order to support surgical decision making and teaching easier during intricate neurosurgical procedures.

One of the most recent innovations in surgical microscopy is the use of augmented reality surgical fluorescence systems for vascular neurosurgery.

Augmented reality is a new approach which provides a totally new view during vascular neurosurgery. This type of system provides a simultaneous, natural colour view of the surgical field overlaid with real-time vascular flow, and full depth perception (without any misalignment between the two images). Using the augmented reality microscope, the images can be utilised simultaneously for a more natural and intuitive viewing of the anatomy. (Previously, surgeons had to switch between the two microscopy modality images, and remember what they saw on one as they’re looking at the other).

With augmented reality (AR) fluorescence and ICG (Indocyanine Green) the surgeon can observe cerebral anatomy in natural colour, augmented by real-time vascular flow (in green), with full depth perception.

There is no requirement to interrupt the surgery to switch between the natural microscope image and a flat black and white near infrared video (older technology), and therefore no need to recall and reconcile the different views.

This new technology has:

• A sophisticated multispectral imaging sensor is able to simultaneously capture multiple spectral bands of visible and fluorescent light
• A real-time algorithm optimizes each spectral band for faithful natural colouring of tissue and accurate representation of fluorescence intensity
• Images are combined for a single, augmented view of the surgical field.

The neurosurgeon has excellent spatial orientation clear delineation of the vessels. This technology, when fully adopted in the future, will have a significant impact on surgical outcomes.

Augmented reality fluorescence combines the high contrast of Near Infrared (NIR) fluorescence imaging with the full visual spectrum of white light into a single, real-time image, the surgeons are able to see the white light image combined with coloured NIR fluorescence flow in real-time.

By overlaying the coloured AR fluorescence image in the oculars, the surgeon has a more complete view of anatomical structures with no interruption or reorientation needed.

An augmented view during vascular neurosurgery can improve decision making during the surgical intervention as the surgeon has a complete view of the anatomy and physiology to support crucial decisions and actions during the vascular neurosurgery procedure.

These new augmented technologies can be fully integrated into current premium neurosurgical microscopes. This gives surgeons and hospitals flexibility to upgrade some of their existing technology, therefore helping them to remain at the cutting edge with regard to advances in augmented reality imaging.

Sources:

https://www.ncbi.nlm.nih.gov/pubmed/10538337
https://www.medgadget.com/2018/09/leicas-augmented-reality-surgical-microscope-combines-fluoroscopy-and-natural-color-vision.html
https://www.leica-microsystems.com/products/surgical-microscopes/details/product/glow800/
https://www.mitpressjournals.org/doi/abs/10.1162/105474600566862
https://en.wikipedia.org/wiki/Augmented_reality-assisted_surgery
http://dbsurgical.com/tag/glow800/
https://youtu.be/mUTg7G9XwGk?t=174