Incidence, follow-up, and postnatal clinical progress of children with central nervous system anomalies on fetal MRI.

OBJECTIVE: MRI is increasingly employed to assess intrauterine fetal anomalies. Central nervous system (CNS) anomalies are common structural conditions that warrant evaluation with fetal MRI and subsequent prenatal consultation with a pediatric neurosurgeon. As the use of fetal MRI increases, there is greater impetus to understand the most common CNS structural anomalies diagnosed in utero, as well as their natural histories. METHODS: The authors performed a single-center retrospective review of fetal MRI evaluations performed between January 2012 and December 2020. Children who underwent both prenatal and postnatal neurosurgical evaluations of CNS anomalies were included. Specific CNS anomalies on fetal MRI, associated extra-CNS findings, and suspicion for genetic abnormality or syndromes were noted. Postnatal clinical status and interventions were assessed. RESULTS: Between January 2012 and December 2020, a total of 469 fetal MRI evaluations were performed; of these, 114 maternal-fetal pairs had CNS anomalies that warranted prenatal consultation and postnatal pediatric neurosurgical follow-up. This cohort included 67 male infants (59%), with a mean ± SD follow-up of 29.8 ± 25.0 months after birth. Fetal MRI was performed at 27.3 ± 5.8 weeks of gestational age. The most frequently reported CNS abnormalities were ventriculomegaly (57%), agenesis or thinning of the corpus callosum (33%), Dandy-Walker complex (DWC) (21%), neuronal migration disorders (18%), and abnormalities of the septum pellucidum (17%). Twenty-one children (18%) required neurosurgical intervention at a mean age of 2.4 ± 3.7 months. The most common surgical conditions included myelomeningocele, moderate to severe ventriculomegaly, encephalocele, and arachnoid cyst. Corpus callosum agenesis or thinning was associated with developmental delay (p = 0.02) and systemic anomalies (p = 0.05). The majority of prenatal patients referred for DWC had Dandy-Walker variants that did not require surgical intervention. CONCLUSIONS: The most common conditions for prenatal neurosurgical assessment were ventriculomegaly, corpus callosum anomaly, and DWC, whereas the most common surgical conditions were myelomeningocele, hydrocephalus, and arachnoid cyst. Only 18% of prenatal neurosurgical consultations resulted in surgical intervention during infancy. The majority of referrals for prenatal mild ventriculomegaly and DWC were not associated with developmental or surgical sequelae. Patients with corpus callosum abnormalities should be concurrently referred to a neurologist for developmental assessments.

Myelomeningocele Including Fetal Prescription.

Myelomeningocele (MMC) is one of the most common birth defects, affecting 0.2 to 0.4 per 1,000 live births in the United States. The most strongly associated risk factor is low folate level in pregnancy. For this reason, 0.4- to 1.0-mg supplementation with folic acid is recommended in all pregnancies, and high-risk pregnancies are recommended to supplement with 4.0 mg of folic acid daily. The mechanism behind the development of MMC is believed to be failure of the caudal end of the neural tube to close during primary neurulation. Screening for MMC is achieved by using α-fetoprotein levels in maternal serum or amniocentesis in the first and second trimesters of pregnancy. Ultrasonography and fetal magnetic resonance imaging are used to confirm the presence of MMC as well as the location and size of the defect. Based on the results of the Management of Myelomeningocele Study, fetal repair is performed between 23 weeks and 25 weeks and 6 days of gestational age for appropriate candidates. Postnatal repair is more common and is performed 24 to 72 hours after birth. In general, patients with lesions at lower anatomical levels have a better prognosis. Most children with MMC will have neurogenic bladder and bowel dysfunction that affect the patient's and the caregiver's quality of life. Patients with higher levels of mobility, better familial support, and higher economic status report improved quality of life compared with other patients with MMC.

Surgical management of quadrigeminal cistern arachnoid cysts: case series and literature review.

OBJECTIVE: Quadrigeminal cistern arachnoid cysts (QACs) are congenital lesions that can cause pineal region compression and obstructive hydrocephalus when sufficiently large. Management of these cysts is controversial and rates of reintervention are high. Given the limited data on the management of QACs, the authors retrospectively reviewed 20 years of cases managed at their institution and performed a literature review on this topic. METHODS: The authors performed a retrospective analysis of patients treated for QAC at their institution between 2001 and 2021. They also performed a literature review of studies published between 1980 and 2021 that reported at least 5 patients treated for QACs. Patient characteristics, radiographic findings, management course, and postoperative follow-up data were collected and analyzed. RESULTS: A total of 12 patients treated for a QAC at the authors' institution met the inclusion criteria for analysis. Median age was 9 months, mean cyst size was 5.1 cm, and 83% of patients had hydrocephalus. Initial treatment was endoscopic fenestration in 92% of these patients, 27% of whom had an endoscopic third ventriculostomy (ETV) performed concurrently. Reintervention was required in 42% of patients. Cases that required reintervention had a statistically significant lower median age at the initial intervention (5 months) than the cases that did not require reintervention (24.33 months; p = 0.018). There were no major complications. At a mean follow-up of 5.42 years, 83% of patients had improvement or resolution of their symptoms. A literature review revealed 7 studies that met the inclusion criteria, totaling 108 patients with a mean age of 8.8 years. Eighty-seven percent of patients had hydrocephalus at presentation. Ninety-two percent of patients were initially treated with endoscopic fenestration, 44% of whom underwent concurrent ETV. Complications occurred in 17.6% of cases, and reintervention was required in 30.6% of cases. The most frequent reason for reintervention was untreated or unresolved hydrocephalus after the initial procedure. CONCLUSIONS: Endoscopic fenestration is the most common treatment for QACs. While generally safe and effective, there is a high rate of reintervention after initial treatment of QACs, which may be associated with a younger age at the first intervention. Additionally, identifying patients who require initial treatment of hydrocephalus is critically important, as the literature suggests that untreated hydrocephalus is a common cause of reintervention.

Macrocephaly in the Primary Care Provider's Office.

Macrocephaly is commonly encountered in the primary care provider's office. It is defined as an occipitofrontal circumference that is greater than 2 standard deviations above the mean for the child's given age. Macrocephaly is a nonspecific clinical finding that may be benign or require further evaluation. An algorithmic approach is useful for aiding in the clinical decision-making process to determine if further evaluation with neuroimaging is warranted. Abnormal findings may signify a harmful underlying cause, requiring referral to a genetic specialist or neurosurgeon.