A BIO-INSPIRED BIOELECTRIC SENSING SYSTEM FOR DEPTH ESTIMATION IN A 3D-PRINTED NEUROVASCULAR MODEL

Minimally invasive neuro-interventional treatments rely on fluoroscopy for catheter navigation, resulting in repeated exposure of neural tissue, patients, and clinicians to ionizing radiation. Inspired by the electrolocation mechanism of weakly electric fish, which sense their surroundings through bioelectric field perturbations, we present a bio-inspired bioelectric sensing system and its experimental validation in 3D-printed neurovascular models. The approach exploits localized bioimpedance variations to estimate vessel geometry and catheter depth without the use of X-ray imaging. To mimic physiologically relevant cerebral vasculature, vascular phantoms incorporating key features such as stenosis, aneurysmal dilations, and bifurcations were designed and fabricated using 3D-printing. Custom intravascular catheters with optimized electrode spacing were integrated with a high-gain, low-noise acquisition circuit and advanced through saline-immersed models to replicate conductive biological environments. Bioimpedance signals recorded during catheter advancement showed consistent and repeatable modulation in response to changes in vessel geometry: signal amplitude increased in narrowed regions and decreased at aneurysmal and bifurcation sites. Quantitative analysis revealed an inverse relationship between measured voltage and local vessel cross-sectional area, supporting the feasibility of depth and structural estimation based on bioelectric cues. These results validate the use of bio-inspired electrosensory principles for intravascular sensing in anatomically realistic 3D-printed neurovascular models and establish a foundation for developing radiation-free guidance strategies for future neuro-interventional applications. Supported by TUSEB- 39026.