Fluoroscopic Myelography-Guided Lumboperitoneal Shunt Placement to Reduce the Risk of Spinal Subdural-Extra-Arachnoid Catheter Misplacement: A Technical Note.

BACKGROUND

Lumboperitoneal (LP) shunting is an established treatment for idiopathic normal pressure hydrocephalus (iNPH). However, lumbar catheter misplacement into the spinal subdural-extra-arachnoid space (SSES) can cause shunt malfunction. We describe a fluoroscopy-assisted LP shunt placement technique combined with limited intraoperative spinal myelography to facilitate catheter placement accuracy.

METHODS

Between January 2023 and June 2025, 12 consecutive patients underwent LP shunt placement using fluoroscopic guidance. Lumbar puncture and catheter insertion were performed under real-time imaging, and 3-5 mL of intrathecal nonionic iodinated contrast was injected to confirm subarachnoid spread prior to catheter advancement. Postoperative computed tomography was obtained to verify catheter positioning. Patients were followed clinically for at least three months.

RESULTS

All procedures were technically successful, with accurate subarachnoid catheter placement confirmed on postoperative CT. No cases of subdural or epidural misplacement, kinking, or caudal deviation were observed. One patient developed an acute subdural hematoma after a fall, one had bilateral chronic subdural hematomas managed conservatively, and one required shunt revision due to catheter fracture. No infection, allergic reaction, or catheter obstruction occurred. The mean follow-up duration was 333 days (range, 96-879).

CONCLUSIONS

In this series, fluoroscopy-assisted LP shunt placement with limited intraoperative spinal myelography allowed real-time confirmation of subarachnoid catheter positioning. This technique appears technically feasible and may help prevent SSES-related malfunction by reducing the risk of catheter misplacement during LP shunt surgery.