Click here to view next page of this article


Myelomeningocele and Other Congenital Malformations of the Central Nervous System

The diagnosis of myelomeningocele is obvious at birth as a CSF-filled sac protruding through a cutaneous defect. The lesion should be covered with sterile, saline-soaked dressings, and the patient is kept prone. After a general assessment, the location of the lesion is noted, and a neurologic examination is performed to assess sensorimotor function in the lower extremities. Anal sphincter tone should be assessed, as over 90% of children with myelomeningocele have bowel and myelomeningocele.

Head circumference should be measured and the anterior fontanelle palpated to assess for hydrocephalus. Following medical stabilization, and preferably within 24 hours of birth.

The long-term outcome of these children has been reported in depth by McLone et al., with an 85% survival rate for those children followed for 8 to 12 years, and 62% having IQs of 80 or greater. With the development of clean intermittent bladder catheterization, fully 85% of children with myelomeningocele.

The development of improved leg braces has allowed children with motor levels of at least L3 function to be community ambulators. McLone's studies have shown that children with myelomeningoceles.

The congenital spinal cord lesions with intact skin are termed spina bifida occulta; they share a common presentation due to tethering of the spinal cord. These lesions also may be associated with an overlying skin lesion, such as a dermal sinus, subcutaneous lipoma, hemangioma, or hairy patch.

In the meningocele, the neural elements are intact, with a CSF-filled sac protruding through a cutaneous defect. Repair is accomplished by localizing the dural defect, amputating the herniating sac, and closing the dura. The remainder of the wound is then closed in layers.

The incidence of encephalocele varies according to geographic region, from as high as 1 in 5000 live births in Southeast Asia to as low as 1 in 10,000 live births in North America. The location of the encephalocele also exhibits geographic variability, with frontonasal encephaloceles more common.

The Chiari I malformation usually presents in a more delayed fashion than the Chiari II malformation, commonly late in the first decade or even into adulthood. Symptoms of Chiari I malformation include headache (often induced by coughing), upper extremity numbness and loss of pain and temperature.

The presentation of intracranial arachnoid cysts is dependent on the age of the patient. Infants commonly present with increased head circumference, full fontanelle, and signs of increased intracranial pressure. Older children may present with headache, seizures, or focal neurologic deficits.