Low level myelomeningoceles: do they need prenatal surgery?

BACKGROUND

Postnatal closure of a myelomeningocele remains the standard of care in many countries. The prenatal closure has given hope for decreasing the damage to the neural placode and has challenged classic management. However, this technique presents potential sources of complications. Patients with MMC with an anatomical level of L4 and below have a better functional prognosis than higher level malformations. Are they still candidates for prenatal surgery?

OBJECTIVE

To evaluate outcome of MMC with an anatomical level of L4 and below and discuss, with support of the literature, the indications to perform prenatal closure in this particular group of patients.

MATERIALS AND METHODS

Twenty-nine children were included in this observational study. The level of the vertebral malformation was sacral in 12 cases (41.4%) or lumbar (level ≤ L4) in 17 cases (58.6%). All the patients was operated postnatally for closure of the MMC with microsurgical technique as soon as possible after clinical evaluation (range 0-97 days).

RESULTS

Only 11 out of 29 patients (37.9%) needed of a CSF diversion. A Chiari II malformation was present before MMC closure in 17 patients (58.6%) and only in 5 (17%) after. Twenty-six patients (89.7%) were able to walk. Seven (23%) and 16 (55%) of our patients have a normal bladder and bowel control, respectively. All school-aged children attend school.

CONCLUSIONS

The functional outcome for low-level MMC is good when managed with modern microneurosurgical techniques with a low risk for the patient and the mother. Therefore, we do not suggest prenatal surgery for subgroup of infant with MM.

Reflections upon the intrauterine repair of myelomeningocele

The intrauterine repair of myelomeningocele presents certain advantages and has gained widespread acceptance. It significantly reduces the incidence of Chiari-2 anomalies and hydrocephalus, and it is thought to enhance the neurologic outcome. Nevertheless, several issues remain unsettled and there are no negligible disadvantages. After working with patients with myelomeningocele for 30 years, I thought about how we currently treat them. There are ethical, organizational, neurological, obstetrical, and postnatal aspects worth discussing.

Surgical Management of Myelomeningocele

Myelomeningocele (MMC) is one of the most common abnormalities of the central nervous system that causes significant neurological impairment. Traditionally, treatment consisted of postnatal closure with the management of the complications, such as ventricular shunting. MMC is a plausible candidate for in-utero surgery because of the mechanism of neurologic damage that begins with abnormal neurulation and continues throughout gestation. Researchers discussed the benefits of in-utero closure prior to the publication of the prospective randomized multicenter Management of Myelomeningocele Study (MOMS trial). Compared to postnatal repair with maternal complications and prematurity as trade-offs, prenatal repair reduced shunting, reversed hindbrain herniation, and improved neurological function. This article discusses the diagnosis, evaluation, long-term follow-up, surgical options, and innovative treatment for fetal myelomeningocele.