Neural tube defects and spinal dysraphism: SAQ

This boy has an open lumbosacral myelomeningocele with the Chiari II malformation and early hydrocephalus. The exposed neural placode with the cerebrospinal fluid leak is the classic open lesion, and the motor level, which is around L2 to L3 given that he moves his hips but not his knees or ankles, predicts a significant motor deficit. The full fontanelle and the head circumference on the 97th centile point to the hydrocephalus that complicates most myelomeningoceles. The priorities are the latex-free protection, the neurosurgical closure within 24 to 72 hours, and the management of the hydrocephalus and the neurogenic bladder. ^[1]

Question 1 (10 marks)

Outline the immediate neonatal management, the investigations, and the definitive care for this boy, including the time frame for the closure and the approach to the hydrocephalus. ^[1]

I would treat this as a neurosurgical emergency in a latex-free environment. My first move is to call the neonatal and the neurosurgical teams at the outset, because the definitive treatment is the operative closure. I would keep the boy in a latex-free environment from the first contact, because the latex sensitisation that complicates spina bifida begins with the early exposure, and the latex-free status would be documented and flagged at every admission. ^[1]

I would place the boy prone or lateral to keep the pressure off the sac, and I would cover the lesion with a sterile saline-soaked dressing that is changed regularly to keep the placode moist and clean. I would start the broad-spectrum antibiotics that cover the skin flora, such as a first-generation cephalosporin, while awaiting the closure. I would secure the intravenous access and check the bedside glucose, because the mother has type 1 diabetes and the boy is at risk of the hypoglycaemia. ^[1]

The investigations would run in parallel. I would order a cranial ultrasound or a magnetic resonance imaging of the brain to map the Chiari II malformation and the hydrocephalus, with the downward herniation of the cerebellar vermis and the brainstem through the foramen magnum and the ventriculomegaly. I would order a spinal magnetic resonance imaging to map the level and the extent of the lesion and to look for the diastematomyelia, the lipoma, and the dermal sinus that may accompany it. ^[7]

The definitive care is the neurosurgical closure within 24 to 72 hours of birth. The surgeon frees the neural placode from the surrounding tissue, reconstructs the neural tube, closes the meninges, and brings the muscle and the skin over the defect. The early closure prevents the infection and preserves the remaining neurological function. The hydrocephalus is managed with the ventriculoperitoneal shunt, placed when the ventriculomegaly progresses, either at the time of the lesion closure or soon after. I would watch for the stridor, the swallowing difficulty, and the apnoea of the Chiari II, which would need the posterior fossa decompression once the shunt malfunction is excluded. ^[7]