Percutaneous Fenestration of a Spinal Arachnoid Web Using an Intrathecal Catheter: Effect on Cerebrospinal Fluid Flow and Clinical Status.

Background: Spinal arachnoid webs are a rare anatomic entity manifesting as neuropathic back pain, compressive myelopathy, radiculopathy, and hydrocephalus. Typical treatments include hemilaminectomy or full laminectomy with durotomy and microsurgical resection, which can result in secondary scarring and recurrent blockage of cerebrospinal fluid (CSF) flow perpetuating the cycle.

Case Description: A 66-year-old woman presented with progressively worsening gait and memory. Magnetic resonance imaging demonstrated an arachnoid web in the high thoracic region, causing CSF flow obstruction and hydrocephalus. A standard lumbar drainage catheter was introduced percutaneously into the lumbar thecal sac and advanced in a cephalad direction, across the arachnoid web, to the high thoracic region. The patient underwent continuous CSF drainage through this catheter for a total of 3 days, displaying measurable clinical improvement that persisted at the 3-month follow-up visit. Phase-contrast magnetic resonance imaging demonstrated interval reconstitution of dorsal synchronous CSF flow at the second thoracic vertebral level, both on day 3 and at the 3-month control imaging study.

Conclusions: This minimally invasive approach seems useful in achieving restoration of spinal fluid flow at the thoracic region when the underlying blockage results from an arachnoid web and leads to quantifiable clinical improvement.