Question

Describe fetal management of lumbosacral meningomyelocele (MMC).

Hint:

Fetal surgery for MMC is a high-risk but potentially highly beneficial procedure, as it can lead to better neurological outcomes and reduce postnatal complications.

Answer 1

Lumbosacral meningomyelocele (MMC) is a neural tube defect (NTD) where both the meninges and spinal cord herniate through an opening in the vertebral column. Fetal management of MMC focuses on preventing further neurological damage, improving the outcomes for the baby, and reducing the risk of complications after birth.
Step 1: Fetal Diagnosis:
1. Ultrasound: The diagnosis of MMC is usually made during routine prenatal ultrasound screening, typically performed between 18-20 weeks of gestation. The presence of a fluid-filled sac with visible neural tissue protruding from the spine confirms the diagnosis.
2. Amniocentesis: Amniocentesis can be performed to check for elevated alpha-fetoprotein (AFP) levels, which indicate an open neural tube defect like MMC.
3. MRI: In some cases, an MRI may be used for a more detailed anatomical assessment, especially to evaluate the degree of spinal cord involvement.
Step 2: Fetal Surgery:
1. Fetal Surgery (Open Surgery): The option of fetal surgery involves closing the defect on the back of the fetus to prevent further damage to the spinal cord and prevent infection. The procedure typically occurs between 19-25 weeks of gestation and requires highly specialized surgical teams.
2. In-utero Therapy: In-utero surgery is associated with better outcomes compared to postnatal surgery, as it may improve motor function and reduce the need for shunt placement for hydrocephalus. However, this surgery carries risks such as preterm labor and possible fetal injury.
Step 3: Postoperative Care and Monitoring:
1. Monitoring the Mother: The mother is monitored for signs of premature labor after fetal surgery. Medications to prevent preterm labor are often administered.
2. Post-Surgery Care: After surgery, the fetus should be monitored for signs of neurological improvement, and further management will depend on the severity of the condition.