Imaging Peripheral Nerves In Vivo with CT Neurogram Using Novel 2,4,6-Tri-Iodinated Lidocaine Contrast Agent

Area of Science:

• Biomedical Engineering
• Radiology
• Neuroscience

Background:

• Peripheral nerve injuries are a significant complication in surgery, leading to chronic pain and functional deficits.
• Current imaging techniques struggle with preoperative and intraoperative visualization of peripheral nerves.
• Accurate nerve identification is crucial for preventing surgical nerve damage.

Purpose of the Study:

• To synthesize and evaluate a novel tri-iodinated lidocaine-based contrast agent for computed tomography (CT) neurography.
• To assess the agent's efficacy in enhancing peripheral nerve visibility in vivo.
• To determine the agent's potential for intraoperative nerve protection and its safety profile.

Main Methods:

• Synthesis and characterization of a tri-iodinated lidocaine analogue.
• Molecular docking for sodium channel affinity assessment.
• In vitro radiodensity comparison with Omnipaque using Hounsfield units (HU).
• In vivo micro-CT imaging of rat sciatic nerves.
• Assessment of nerve conduction blockade and histological analysis for neurotoxicity.

Main Results:

• The tri-iodinated lidocaine analogue demonstrated high affinity for voltage-gated sodium channels.
• In vitro radiodensity was comparable to the commercial contrast agent Omnipaque.
• In vivo CT imaging clearly visualized the sciatic nerve with significantly increased HU values.
• Transient nerve conduction blockade was confirmed without observable histological damage.

Conclusions:

• A novel tri-iodinated lidocaine-based contrast agent enables clear CT visualization of peripheral nerves.
• The agent acts as a reversible nerve conduction blocker, supporting its dual function.
• This agent holds potential for improving preoperative planning and intraoperative nerve protection during surgery.