Complications of Therapies for Arachnoid Cysts of the Head and Spine in Children

Surgical

Pseudomeningocele/CSF wound leakage: Subcutaneous collections of CSF, which may leak through the wound, can lead to meningitis and should be managed aggressively. These fluid collections can be a sign of postoperative hydrocephalus, which may require draining or shunting. Other considerations for the etiology of these fluid collections can be infection (which can be evaluated by tapping) or poor wound closure (requiring surgical address).

Intracranial cyst fenestration

• Hemiparesis: Hemiparesis can occur from cerebral retraction. This is usually temporary and may improve with steroids. Imaging should be performed to evaluate for a hematoma. Care should be taken to avoid injury to the middle cerebral artery, which may be exposed in cases of large cysts. The carotid artery should be visualized during fenestration and should not be retracted during surgery.
• Cranial nerve palsies: Third nerve palsies can occur during fenestration into the basilar cisterns. This nerve should be readily visualized and care taken to avoid retraction.
• Hypothalamic injury: Hypothalamic injury can occur when sellar/suprasellar cysts are aggressively fenestrated. Care should be taken to avoid compromise of the perforating vessels in these cases. Care is supportive, with appropriate endocrine replacement and blood pressure management.
• Increased seizure frequency: Seizures may increase due to brain shift, brain retraction, replacement of CSF with irrigating solution, anesthesia withdrawal, or alteration in preoperative seizure medication. These seizures can typically be managed medically. Hematomas should be considered, and imaging should be performed.
• Postoperative hematomas: Hematomas may result from poor hemostasis, stretching and tearing of bridging veins due to brain shift, and/or contusions from retraction. These can be particularly dangerous due to the resultant spaces from the fenestrated cyst. Surgical evacuation is indicated if the hematoma is large and/or symptomatic.

Intracranial cyst shunting

• Shunt malfunction: Cyst shunts may become occluded, resulting in cyst enlargement and/or neurological signs and symptoms. In these cases, shunt revision may be indicated.
• Shunt infection: Cyst shunts can become infected in either an early or a delayed fashion. Antibiotics and surgical removal with external drainage are typically indicated.
• Shunt overdrainage: Cysts are typically drained to low pressure to ensure that they collapse. However, if the cyst communicates with the CSF spaces, overdrainage may occur. This problem can be addressed by placing a higher pressure valve or considering shunt removal if the cyst has collapsed.