From the Research
Lumbosacral myelomeningocele causes obstruction of cerebrospinal fluid (CSF) flow primarily through the Chiari II malformation that typically accompanies it, leading to hydrocephalus in approximately 80-90% of patients. This congenital defect involves the downward displacement of the cerebellum, brainstem, and fourth ventricle through the foramen magnum into the cervical spinal canal, creating a mechanical blockage at the level of the fourth ventricle and foramen magnum, preventing normal CSF circulation from the ventricles to the subarachnoid space 1. Additionally, the malformation often causes stenosis of the cerebral aqueduct (aqueduct of Sylvius), further impeding CSF flow between the third and fourth ventricles. The obstruction leads to CSF accumulation in the ventricles, resulting in hydrocephalus.
Key Points
- The severity of obstruction can vary depending on the extent of the neural tube defect and associated malformations.
- Early recognition and treatment of hydrocephalus with ventriculoperitoneal shunting or endoscopic third ventriculostomy is crucial to prevent increased intracranial pressure and subsequent neurological damage 2.
- The management and prevention of myelomeningocele-associated hydrocephalus has evolved, with treatment modalities including ventriculoperitoneal shunting and endoscopic third ventriculostomy 1.
- A recent study found that hydrocephalus treatment has become more delayed, and the number of hydrocephalic myelomeningocele patients not treated on initial inpatient stay has increased 1.
Treatment Considerations
- Ventriculoperitoneal shunting and endoscopic third ventriculostomy are effective treatment options for hydrocephalus associated with myelomeningocele.
- The choice of treatment modality depends on various factors, including the patient's age, medical history, and the presence of associated malformations.
- Early surgical treatment can be considered to prevent deterioration of neurological signs and facilitate improvement of neurological signs 3.
Outcome
- The outcome of patients with myelomeningocele and hydrocephalus can be improved with early recognition and treatment of hydrocephalus.
- The goal of treatment is to prevent increased intracranial pressure and subsequent neurological damage, and to improve the patient's quality of life.