Spinal Imaging Findings of Open Spinal Dysraphisms on Fetal and Postnatal MRI.

BACKGROUND AND PURPOSE: Fetal MRI has become a valuable tool in the evaluation of open spinal dysraphisms making studies comparing prenatal and postnatal MRI findings increasingly important. Our aim was to determine the accuracy of predicting the level of the spinal dysraphic defect of open spinal dysraphisms on fetal MR imaging and to report additional findings observed when comparing fetal and postnatal MR imaging of the spine in this population. MATERIALS AND METHODS: A single-center retrospective analysis was performed of fetal MRIs with open spinal dysraphisms from 2004 through 2016 with available diagnostic postnatal spine MR imaging. Images were reviewed by 2 board-certified fellowship-trained pediatric neuroradiologists. Corresponding clinical/operative reports were reviewed. RESULTS: One hundred nineteen fetal MRIs of open spinal dysraphisms were included. The level of the osseous defect between fetal and postnatal MR imaging was concordant in 42.9% (51/119) of cases and was 1 level different in 39% (47/119) of cases. On postnatal MR imaging, type II split cord malformation was seen in 8.4% (10/119) of cases, with only 50% (5/10) of these cases identified prospectively on fetal MR imaging. Syrinx was noted in 3% (4/119) of prenatal studies, all cervical, all confirmed on postnatal MR imaging. CONCLUSIONS: Fetal MR imaging is accurate in detecting the level of the spinal dysraphic defect, which has an impact on prenatal counseling, neurologic outcomes, and eligibility for fetal surgery. In addition, fetal MR imaging is limited in its ability to detect split cord malformations in patients with open spinal dysraphisms. Although rare, fetal MR imaging has a high specificity for detection of cervical spinal cord syrinx.

Hindbrain Herniation in Chiari II Malformation on Fetal and Postnatal MRI.

BACKGROUND AND PURPOSE: As the practice of in utero repair of myelomeningoceles becomes more prevalent, knowledge of the expected MR imaging findings has become increasingly important. Our aim was to examine neuroimaging findings with a focus on hindbrain herniation and ventricular size in fetuses with open spinal dysraphism and to compare them with postnatal imaging features in groups undergoing prenatal-versus-postnatal repair. MATERIALS AND METHODS: Single-center retrospective analysis was performed on MRIs of fetuses with open spinal dysraphism from January 2004 through July 2015 with available postnatal imaging. One hundred two fetuses were included. Reports from available fetal ultrasound were also examined. Images were reviewed by 2 board-certified fellowship-trained pediatric neuroradiologists. Descriptive analyses were performed to demonstrate the distribution of the imaging findings. RESULTS: Thirty-two of 102 (31.3%) fetuses underwent in utero repair of open spinal dysraphism; 68.6% (70/102) underwent postnatal repair. Ninety-four of 102 (92.2%) fetuses had cerebellar ectopia. Of those who underwent prenatal repair (26 grade 3, 6 grade 2), 81.3% (26/32) had resolved cerebellar ectopia postnatally. Of those who had severe cerebellar ectopia (grade 3) that underwent postnatal repair, 65.5% (36/55) remained grade 3, while the remaining 34.5% (19/55) improved to grade 2. The degree of postnatal lateral ventriculomegaly in those that underwent prenatal repair (20.3 ± 5.6 mm) was not significantly different from that in those that underwent postnatal repair (21.5 ± 10.2 mm, P = .53). Increased Chiari grade was significantly correlated with decreased head size for gestational age on fetal sonography (P = .0054). CONCLUSIONS: In fetuses with open spinal dysraphism and severe Chiari II malformation that do not undergo prenatal repair, most have no change in the severity of cerebellar ectopia/Chiari grade. However, in fetuses that undergo in utero repair, most have resolved cerebellar ectopia postnatally.

Identification and management of neonatal skull fractures.

OBJECTIVE: Suspected skull fractures in the neonate are uncommon and present a management dilemma. We hypothesized that skull fractures are more common than reported in the literature and that few infants require any intervention. STUDY DESIGN: We retrospectively reviewed the charts of 21 infants referred to our level IV Neonatal Intensive Care Unit for possible skull fracture over a 3-year period after birth trauma, suspicious findings on clinical exam, or accidental falls in the birth hospital. RESULTS: Skull films at the birth hospital were unreliable for fracture in 23% of cases. Seven of nine infants with accidental falls had fracture on computed tomography scan. Only three infants required neurosurgical intervention, all after severe birth trauma associated with instrumentation. CONCLUSION: Skull fractures are more common than previously reported in neonates after accidental falls, but few infants with skull fractures require neurosurgical intervention.

Evaluation of Subependymal Gray Matter Heterotopias on Fetal MRI.

BACKGROUND AND PURPOSE: Subependymal grey matter heterotopias are seen in a high proportion of children with Chiari II malformation and are potentially clinically relevant. However, despite its growing use, there is little in the literature describing its detection on fetal MRI. Our aim was to evaluate the accuracy in diagnosing subependymal gray matter heterotopias in fetuses with spinal dysraphism on fetal MR imaging. MATERIALS AND METHODS: This study is a retrospective analysis of 203 fetal MRIs performed at a single institution for spinal dysraphism during a 10-year period. Corresponding obstetric sonography, postnatal imaging, and clinical/operative reports were reviewed. RESULTS: Of the fetal MRIs reviewed, 95 fetuses were included in our analysis; 23.2% (22/95) were suspected of having subependymal gray matter heterotopias on fetal MR imaging prospectively. However, only 50% (11/22) of these cases were confirmed on postnatal brain MR imaging. On postnatal brain MR imaging, 28.4% (27/95) demonstrated imaging findings consistent with subependymal gray matter heterotopia. Only 40.7% (11/27) of these cases were prospectively diagnosed on fetal MR imaging. CONCLUSIONS: Fetal MR imaging is limited in its ability to identify subependymal gray matter heterotopias in fetuses with spinal dysraphism. It is believed that this limitation relates to a combination of factors, including artifacts from fetal motion, the very small size of fetal neuroanatomy, differences in imaging techniques, and, possibly, irregularity related to denudation of the ependyma/subependyma in the presence of spinal dysraphism and/or stretching of the germinal matrix in ventriculomegaly.

Chiari type I malformation in children and adolescents with cystic fibrosis.

Chiari type I malformation is characterized by herniation of the cerebellar tonsils through the foramen magnum. An association between Chiari type I malformation and cystic fibrosis (CF) has not previously been established. We report on five children and adolescents with CF in whom Chiari type I malformations were diagnosed. Three patients were 17-18 years old at time of diagnosis, one was 3 years old, and one was 10 months of age. All patients were followed at the Cystic Fibrosis Center at St. Christopher's Hospital for Children and were diagnosed with the malformations between June 1988 and June 1997. Over this same period, 400 CF patients 18 years or younger were followed routinely. All patients had the diagnosis of Chiari type I confirmed by brain-stem MRI. Neurologic findings included swallowing dysfunction, syncopal episodes, numbness of extremities, recurrent vomiting, and headaches. No two patients had the same presenting neurologic findings. Our data suggest that Chiari type I malformation is more common in CF than in the general population. The possibility of Chiari type I malformation should be included in the differential diagnosis of unexplained neurologic complaints in patients with CF.

Head injuries in children from plastic hairbeads.

BACKGROUND: Plastic hairbeads are often worn as decorative hair fasteners by children. Serious, penetrating head injuries may result from their use and have been observed in some children following a fall. OBJECTIVE: The objective of this report is to describe the imaging findings in children who have sustained head injury while wearing plastic hairbeads. MATERIALS AND METHODS: Three children with significant head injuries resulting from embedded hairbeads are described. Three additional cases of minor head injury reported to the Consumer Product Safety Commission are summarized. RESULTS: One child sustained a minimally depressed skull fracture without brain injury. The second child required surgical repair of a depressed skull fracture complicated by a parenchymal hemorrhage and dural tear. A third child required surgical evacuation of an organized, liquefied epidural hematoma 2 weeks after an initial evaluation at an outside emergency room. CONCLUSION: Children wearing plastic hairbeads are at risk for severe head injury following a fall. Caution must accompany their use.

Reflections on the natural history of lipomyelomeningocele.

A retrospective analysis of patients with lipomyelomeningocele cared for at two referral centers was completed to derive relationships between neurological function and patient age. Thirty-seven percent of 177 patients had intact neurological function on initial examination. Neurological deficits were progressive and linked with a logarithmic relationship to increasing patient age. Each child with intact examination retained normal bladder function following lipomyelomeningocele repair and release of cord tethering; complications of surgery were limited. Our analysis suggests that surgery on patients with intact function offers greater long-term protection of critical function than is offered by conservative management and expectant care. We recommend repair of lipomyelomeningocele at the time of diagnosis regardless of patient age or neurological function.

A prospective, randomized study of shunt function and infections as a function of shunt placement.

Much controversy still exists about the relative advantages and disadvantages of anteriorly vs. posteriorly placed shunts in terms of infection rate and duration of function. During a 27-month period, all 121 patients seen requiring new shunt insertions were prospectively randomized to anterior or posterior placement. The mean duration of follow-up was 15 months. 70% of the shunts in the posteriorly placed group vs. 59% of the shunts in the anteriorly placed group did not require further surgery during the study period. In a life-table analysis of shunt survival as a function of placement, the shunts in the posteriorly placed group 'survived' slightly longer without malfunctioning or becoming infected than the anteriorly placed shunts. Therefore, the authors conclude that anteriorly placed shunts offer no advantage over posteriorly placed shunts in terms of shunt malfunction or infection.