Delayed Cranial Nerve Palsies and Chiari Type I Malformation After Epidural Anesthesia in the Setting of Childbirth

Abstract

Epidural analgesia is an efficient method of controlling pain and has a wide spectrum of therapeutic and diagnostic applications. Potential complications may occur in a delayed fashion, can remain undiagnosed, and can be a source of significant morbidity. We present a 37-year-old woman presented with severe spontaneous occipital headaches, diplopia, and dizziness that occurred spontaneously six weeks after giving birth. Her primary method of pain control during labor was epidural analgesia. Her neurologic exam revealed a cranial nerve six palsy with ptosis, and her brain MRI demonstrated a Chiari I malformation which had not been previously diagnosed. CT myelography of the lumbar spine revealed extradural contrast extravasation within the interspinous soft tissue at L1-L2, which was the site of her prior epidural procedure. She underwent epidural blood patch administration, and her cranial nerve palsy resolved along with all of her other symptoms. The development of concurrent Chiari I malformation and cranial nerve palsy after epidural anesthesia is an exceptionally rare occurrence. Neurologic complications after epidural anesthesia are likely under-reported, since patients are often lost to follow-up or have subtle neurologic signs which can easily be missed. This frequently delayed presentation emphasizes the importance of patient education and the necessity of a detailed neurological exam when symptoms occur.

A child with unilateral abducens nerve palsy and neurovascular compression in Chiari malformation type 1 resolved with posterior fossa decompression: illustrative case

“…Caruso et al. 24 reported a 37-year-old postpartum female 6 weeks status post-epidural anesthesia with intracranial hypotension including headaches, dizziness, and CN VI palsy. Imaging demonstrated CM1, which was thought to be exacerbated by CSF leakage.…”

“…These include cases of CSF diversion and hydrocephalus, as well as several cases of central nervous system hypotension following lumbar puncture. 14 , 24 In these cases, some suggest that CN VI is stretched by pressure changes and subjected to traction away from its tether point in Dorello’s canal, pulling it upward in the case of increased ICP or downward in the case of CSF leakage and decreased ICP. Given that Chiari decompression surgery is a flow-normalizing procedure that restores CSF circulation across the cisterna magna, it is possible that PFDD in our case led to normalized pressure and flow, eliminating both any possible traction and neurovascular mass effect.…”

“…Massey et al 23 reported a 4-year-old female with acute-onset unilateral abducens nerve palsy accompanied by torticollis and CN VII palsy, ataxic gait, lower-extremity spasticity with clonus, and bilateral Babinski reflexes, who was found to have CM1 with holochord syringomyelia and syringobulbia. Caruso et al 24 reported a 37-year-old postpartum female 6 weeks status post-epidural anesthesia with intracranial hypotension including headaches, dizziness, and CN VI palsy. Imaging demonstrated CM1, which was thought to be exacerbated by CSF leakage.…”