Laminotomy for Targeted Injection into the Lumbar Dorsal Root Ganglion in a Pig Model

Begin with an anesthetized pig with three lumbar vertebrae surgically exposed.

Identify the lamina, a flat bone between the spinous process and facet joints.

Trace it toward the spinal canal while avoiding pressure on the dural sac, the spinal cord’s protective covering.

Remove the lamina in small pieces.

Cut the underneath membrane to expose the fat.

Remove the lower joint to improve access, keeping the upper part intact to maintain spinal stability.

Extract fat to expose the dural sac, dorsal root ganglion (DRG), and nearby spinal nerves.

Identify the DRG, which transmits sensory and pain signals, then insert a convection-enhanced delivery (CED) needle connected to an infusion system into its center.

The CED needle uniformly delivers the dye-loaded solution through positive pressure while minimizing leakage.

This targeted injection enables precise neurotherapeutic delivery to the lumbar DRG.

Finally, withdraw the needle and close the surgical site.

With care, use a five-millimeter Freer elevator or curette to palpate the transition between the caudal-most edge of the lamina and central canal.

Do not force the elevator anterior. Next, using rongeurs, extract bone in a piecewise fashion. Remov