Technical modifications to ABI surgery in children.

Cerebrospinal fluid (CSF) leak is the most frequently reported significant complication in pediatric ABI surgery, occurring in up to 8.5% of patients. Surgical protocols frequently call for a watertight dural closure followed by use of a mastoid/temporal pressure dressing to minimize the risk of CSF fistula and fluid collections. Evidence from cerebellopontine angle surgery confirms that intracranial CSF pressure rises immediately after posterior fossa surgery and normalizes after 48 hours, with impaired absorption the believed cause. This can result in CSF egress around the tract of the ABI electrode cable into the subgaleal space. Complications of pseudomeningocele include skin wound breakdown, meningitis, and need for further surgery. Multiple case reports describe revision surgery on pediatric ABI patients to place fat and other tissue grafts and plating systems to address these issues. Pressure dressing use is also problematic and may provide a false sense of assurance to the operating surgeon. Surgeons have been shown to be unable to accurately assess pressure to prevent magnet migration with dressings during MRI. It is therefore difficult to support the routine use of tight pressure dressings over an implanted device in a thin-scalped child when this could result in a pressure ulcer and devastating wound complication. At our pediatric ABI program, we have begun to perform lumbar subarachnoid drainage routinely for 48 hours postoperatively after retrosigmoid (RS) ABI placement in children as we routinely do in adults having acoustic neuroma surgery. We use dressings for only 24 hours to provide initial counterpressure to prevent pseudomeningocele as the lumbar drain is begun. There have been no complications related to lumbar drain use, and at our pediatric hospital lumbar drains are managed on the regular ward. We believe the combination of lumbar drainage and short pressure dressing use allows for the best risk-benefit profile in these patients. [ABSTRACT FROM AUTHOR]