Neurointerventional optical coherence tomography using a piezo-driven microprobe.

Abstract

Intravascular optical coherence tomography (IV-OCT) is a promising tool for cerebrovascular imaging, but its clinical use remains limited by two unresolved problems: proximal-scanning catheters suffer from non-uniform rotational distortion (NURD) in tortuous vessels, whereas distal-scanning micro-electromagnetic motors are hampered by wire artifacts that block full 360° visualization. Here, we present a piezoelectric-driven micro-optical probe for imaging within complex cerebral vasculature. Using an integrated structure-function design, the probe is compact, measuring 0.55 mm in diameter and 4 mm in length. A slanted-groove configuration converts longitudinal vibration into torsional vibration, enabling wire-artifact-free scanning with a single-phase drive circuit. In a full-scale human cerebrovascular phantom, the probe navigated the middle cerebral artery and rotated uniformly at speeds up to 58 revolutions per second. Imaging of metal-tube phantoms, magnolia-leaf microveins, vascular stents, ex vivo porcine vessels, and human atherosclerotic plaques confirmed that the probe can resolve microvascular architecture, stent geometry, lipid deposits, and fibrotic tissue, with the OCT findings supported by histological analysis. Together, these results indicate that the proposed piezoelectric-driven microprobe offers a viable route toward precise intravascular optical imaging for cerebrovascular interventions.