Our next speaker will be Yi Li, speaking on Bedside Wearable Mixed Reality Holograms Guide External Ventricular Drain Insertion. Hello, everyone, I'm glad to be here today. I'm Yi Li from Beijing, China, and the topic I want to share today is Bedside Mixed Reality Wearable Holograms Guide, EVD Insertion. So I think everyone sitting here knows EVD much better than me, and I think the EVD insertion procedure is well documented in every textbook, and you're all familiar with this picture, right? So I think classically, EVD insertion is a blind procedure performed using freehand technique based on the surface landmarks. So however, inaccurate placement has been well-reported in the literature, some to the contralateral side, some to the third ventricle, and some to the cisterns. So as a matter of fact, the accuracy rate is only near 50%. So nowadays, the image-guided EVD insertion makes great contributions to improve its accuracy. However, such navigational devices are always time and money and space-consuming, which are not routinely used at the bedside. So in order to achieve a low-cost, portable approach, we chose Microsoft HoloLens, a wearable mixed reality head-mounted device, to help us guide the EVD insertion in a more intuitive way. So how did we do it? And before the CT scan, we attached several ECG electrodes on the patient's head. Such radio-dense markers were used for the pre-op registration between the head and the ventricles. And then we performed the CT scan, and then we used these pre-op data to segment the ventricles of the head, the markers, as well as determine the entry and target points. And then, consequently, the insertion trajectories, orientation, and depth are automatically generated. And by wearing the headset, the neurosurgeon could visualize the holograms of the surgical plan in the physical world. So this is how we do a surgical plan in 3D Slicer. First, we segment the ventricles, the markers, and the head, and then determine the insertion target and the entry point. And then, automatically, these insertion trajectories, the orientation, and the depth are automatically calculated. And this is a simple case. Before the CT scan, we attached several ECG electrodes to the patient's head. And again, such radio-dense markers were used for the pre-op registration between the patient's head and the holograms. And by wearing the headset, the neurosurgeon could visualize the pre-op surgical plan in the physical world. Actually, using the gestural control, the virtual markers were precisely superimposed to the patient's cranium and such done the pre-op registration. And the neurosurgeon made a burr hole guided by the trajectory's orientation. And the insertion of the catheter was intuitively guided by this yellow trajectory. And post-op CT verified this accuracy. So in order to verify the feasibility and accuracy of our new technique, we enrolled 15 EVD insertions for holographic guidance and the same number as control. And we also calculated the additional time and compared the number of passes and target deviation between the two groups. So the vectors in this picture represent the actual spatial distribution of target deviation in each case. And we can easily find from this picture that the holographic guidance is much more accurate than the control. And the mean additional time before the surgical part of the procedure began was only 14 minutes. And the average number of passes was only one, compared that to two in control. And the mean target deviation was only four millimeters, compared that to 11 in control. Now we've already invented our own in-house, excuse me, our own in-house software to advance the registration accuracy and user experience. So yeah, in my opinion, with further advancement, such new technique could also be helpful for this intracranial hematoma aspiration, as well as superficial tumor section. Thank you all very much. That's all. Thank you. Any questions? Well, that's fantastic. Have you used it clinically yet? Yes. Oh, OK. Thank you. So how does it know your EVD? So do you need to put a tracker on the EVD? Can you track it at how it goes down? Oh, maybe in the next step. Yeah, it's kind of a little bit complicated than the ECG electrodes. So maybe we can do that later. Fascinating, very interesting. Thank you very much. Thank you all.

Yi Li

Microsoft HoloLens

wearable mixed reality device

Externally Ventricular Drain (EVD) insertion

neurosurgeon