Serendipitous discovery of intrathecal catheterization via the lumbosacral plexus in rats: A preliminary study

Intrathecal catheterization is essential for experimental studies, including drug delivery, stem cell therapy, and gene therapy, but it can sometimes be quite costly. Since traditional techniques, such as acute needle puncture and catheterization with or without laminectomy have shown varying success rates and procedural challenges, there is room for improvement.

This study presents an alternative approach to intrathecal catheterization via the lumbosacral plexus, which was serendipitously discovered during an attempt to cannulate the lymphatic system in male Lewis rats using a 0.010-inch microguidewire and a 1.3-F microcatheter with an over-the-wire technique under fluoroscopic guidance.

Intrathecal catheterization via the left L3 spinal nerve was achieved in 14 out of 17 rats (82 %). In one case, only the microguidewire was inserted, and in two cases, spinal nerve cannulation was unsuccessful. The median catheterization duration was 20 minutes. Accidental intrathecal placement was confirmed by postmortem micro-CT with iodinated contrast and dissection following isosulfan blue staining. No cerebrospinal fluid leakage was observed fluoroscopically during the procedure.

This method demonstrated a higher cannulation rate and a procedural time comparable to traditional techniques such as non-laminectomized catheterization. Additionally, it eliminates the risk of cerebrospinal fluid leakage, a common complication in conventional catheterization approaches. However, motor function impairment due to nerve injury and the need for specialized fluoroscopy settings remain limitations.

This serendipitous discovery suggests that intrathecal catheterization via the lumbosacral plexus may be a feasible alternative approach in select cases.