Design Optimization and Mechanical Performance Evaluation of a Modified Coronary IV-OCT Catheter Adapted for Intracranial Navigation: A Preclinical Study

TL;DR

Researchers improved a coronary imaging catheter to better navigate the brain's complex blood vessels, showing it performs better in mechanical tests and animal trials.

Contribution

A modified coronary IV-OCT catheter was developed and tested for improved performance in intracranial navigation.

Findings

The modified catheter showed significantly better pushability and resistance in simulated vessel navigation.

In vivo tests demonstrated a higher success rate in navigating the external carotid artery curvature.

The modified catheter had a significantly greater catheter tension angle in live trials.

Abstract

The application of intravascular optical coherence tomography (IV-OCT) in neurovascular interventions is constrained by the mechanical inadequacy of conventional catheters in navigating the complex intracranial vasculature. To address this, we modified a coronary IV-OCT catheter, enhancing its mechanical performance for neurovascular applications. The modified catheter featured a 300 mm over-the-microwire segment and a dual-structured shaft (distal 50 mm nonbraided, proximal 250 mm braided) to improve trackability and pushability. We compared the modified and conventional catheters using a benchtop model with a simulated vessel path and an in vivo swine model. Trackability and pushability were quantitatively measured using resistance (N) and advancement distance (mm) in the simulated path. In the animal model, indirect performance metrics included the catheter tension angle (CTA) and pass of catheter (POC) through the fourth curvature of the external carotid artery (ECA). The modified catheter demonstrated superior pushability (172.9 ± 1.96 mm vs. 127.9 ± 2.86 mm, p < 0.05) and increased resistance (1.47 ± 0.036 N vs. 0.69 ± 0.032 N, p < 0.05). In vivo analysis further showed a significantly greater CTA (115.8 ± 8.5° vs. 77.6 ± 10.3°, p < 0.05) and higher POC success rate (83.3% vs. 11.1%, p < 0.05). These results indicate that the modified coronary IV-OCT catheter offers enhanced mechanical performance, suggesting its potential for safe and effective use in neurovascular procedures.

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