Navigation and visualisation with HoloLens in endovascular aortic repair

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Augmented Reality

Background:

• Endovascular aortic repair (EVAR) is a minimally invasive procedure to treat aortic pathologies.
• Current EVAR navigation relies on fluoroscopy and digital subtraction angiography, leading to radiation exposure and contrast agent use.
• The Nav EVAR project seeks to optimize EVAR by integrating advanced navigation, imaging, and augmented reality.

Purpose of the Study:

• To present the iterative development of the Nav EVAR system for enhanced EVAR procedure guidance.
• To evaluate the effectiveness of the developed prototype in reducing side effects and improving visualization.
• To explore the potential of augmented reality and real-time imaging in endovascular interventions.

Main Methods:

• Utilizing an electromagnetic tracking system to guide catheters in real-time, displayed via Microsoft HoloLens augmented reality glasses.
• Integrating 3D vascular models, CT angiograms, and a novel virtual angioscopy into the AR visualization.
• Employing real-time 3D ultrasound and external markers for accurate registration and intraoperative navigation updates.
• Testing the system using a human torso model with a 3D printed patient-specific aortic model, an ultrasound training model, and an aortic-aneurysm phantom.

Main Results:

• Successful visualization of 3D phantom models and vessels on HoloLens during catheter navigation.
• Development of a virtual angioscopy from CT scans, with visible external markers for registration.
• Demonstrated real-time 3D ultrasound streaming to HoloLens with a mean latency of 259±86 ms.

Conclusions:

• The Nav EVAR project offers a multidisciplinary approach to reduce radiation and contrast agent use in EVAR.
• Current limitations include rigid alignment between preoperative data and the patient model.
• The integration of advanced imaging techniques like fiber Bragg gratings and optical coherence tomography shows promise for future EVAR improvements.