Infantile arachnoid cyst compressing the sacral nerve root associated with spina bifida and lipoma--case report

Area of Science:

• Pediatric Neurology
• Neurosurgery
• Developmental Neuroscience

Background:

• Sacral arachnoid cysts are rare intradural lesions.
• They can present with neurological deficits, including gait disturbance.
• Associated conditions like spina bifida occulta and lipomas are common.

Observation:

• A 2-year-old boy presented with progressive gait disturbance due to a sacral arachnoid cyst.
• Neuroimaging revealed an intradural cyst compressing the S-2 nerve root, with an S-2 nerve root piercing the cyst.
• The cyst, lacking communication with the spinal subarachnoid space, likely enlarged via a one-way valve mechanism.

Findings:

• Surgical intervention involved a cyst-subarachnoid shunt to decompress the cyst, avoiding radical resection.
• Postoperative improvement in gait disturbance was observed.
• No neurological deterioration occurred during a 4-year follow-up period.

Implications:

• Sacral arachnoid cysts should be considered in the differential diagnosis of pediatric progressive gait disturbance.
• Tethered cord syndrome is another critical consideration in such cases.
• Cyst-subarachnoid shunting offers a viable alternative to cyst resection for achieving neurological improvement in select cases.