Spinal dysraphism: a review of neuroradiological features with embryological correlations and proposal for a new classification

Imaging Fetal Spine Malformations in the Context of In Utero Surgery

This review covers the embryology, definition, and diagnosis of open spinal dysraphism with a focus on fetal ultrasound and MR imaging findings. Differentiating open versus closed spinal dysraphic defects on fetal imaging will also be discussed. Current fetal surgery practices and imaging findings in the context of fetal surgery are also reviewed.

Brain and spine malformations and neurodevelopmental disorders in a cohort of children with CAKUT

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) represent 20-30% of all birth defects and are often associated with extra-renal malformations. We investigated the frequency of brain/spine malformations and neurological features in children with CAKUT.

METHODS

We reviewed the clinico-radiological and genetic data of 199 out of 1,165 children with CAKUT evaluated from 2006 to 2023 (99 males, mean age at MRI 6.4 years) who underwent brain and/or spine MRI. Patients were grouped according to the type of CAKUT (CAKUT-K involving the kidney and CAKUT-H involving the inferior urinary tract). Group comparisons were performed using χ2 and Fisher exact tests.

RESULTS

Brain/spine malformations were observed in 101/199 subjects (50.7%), 8.6% (101/1165) of our CAKUT population, including midbrain-hindbrain anomalies (40/158, 25.3%), commissural malformations (36/158, 22.7%), malformation of cortical development (23/158, 14.5%), Chiari I anomaly (12/199, 6%), cranio-cervical junction malformations (12/199, 6%), vertebral defects (46/94, 48.9%), caudal regression syndrome (29/94, 30.8%), and other spinal dysraphisms (13/94, 13.8%). Brain/spine malformations were more frequent in the CAKUT-K group (62.4%, p < 0.001). Sixty-two subjects (62/199, 31.2%) had developmental delay/intellectual disability. Neurological examination was abnormal in 40/199 (20.1%). Seizures and/or electroencephalographic anomalies were reported in 28/199 (14%) and behavior problems in 19/199 subjects (9%). Developmental delay/intellectual disability was more frequent in kidney dysplasia (65.2%) and agenesis (40.7%) (p = 0.001).

CONCLUSIONS

We report a relative high frequency of brain/spine malformations and neurodevelopmental disorders in children with CAKUT who underwent MRI examinations in a tertiary referral center, widening the spectrum of anomalies associated with this condition.

Proposal for standardized prenatal assessment of fetal open dysraphisms by the European reference network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies (ITHACA) and eUROGEN

Open dysraphisms, that is, myelomeningocele and myeloschisis, are rare diseases associated with a risk of severe disability, including lower limb motor and sensory deficiency, sphincter deficiency, and potential intellectual deficiency. Open dysraphism is diagnosed in Europe in 93.5% of cases. In case of suspicion of fetal open dysraphism, a detailed fetal morphologic assessment is required to confirm the diagnosis and exclude associated structural anomalies, as well as genetic assessment. In case of isolated fetal open dysraphism, assessment of prognosis is based on fetal imaging including the level of the lesion, the presence or not of a sac, the presence and nature of intra cranial anomalies, and the anatomical and functional evaluation of the lower extremities. Based on these biomarkers, a personalized prognosis as well as comprehensive information about prenatal management alternatives will allow parents to decide on further management options. Standardization of prenatal assessment is essential to compare outcomes with benchmark data and make assessment of surgical innovation possible. Herein, we propose a protocol for the standardized ultrasound assessment of fetuses with isolated open dysraphism.

Morphometric Analysis of Spina Bifida after Fetal Repair Shows New Subtypes with Associated Outcomes

Importance

The binary classification of spina bifida lesions as myelomeningocele (with sac) or myeloschisis (without sac) belies a spectrum of morphologies, which have not been correlated to clinical characteristics and outcomes.

Objective

To characterize spina bifida lesion types and correlate them with preoperative presentation and postoperative outcomes.

Design

Secondary analysis of images and videos obtained during fetoscopic spina bifida repair surgery from 2020-2023.

Setting

Fetal surgery was performed at a quaternary care center.

Participants

A prospective cohort of patients referred for fetal spina bifida underwent fetoscopic repair under an FDA-approved protocol. Of 60 lesions repaired, 57 had available images and were included in the analysis.

Interventions or Exposures

We evaluated lesion morphology on high-resolution intraoperative images and videos to categorize lesions based on placode exposure and nerve root stretching.

Main Outcomes and Measures

The reproducibility of the lesion classification was assessed via Kappa interrater agreement. Preoperative characteristics analyzed include ventricle size, tonsillar herniation level, lower extremities movement, and lesion dimensions. Outcomes included surgical time, need for patch for skin closure, gestational age at delivery, preterm premature rupture of membranes (PPROM), and neonatal cerebrospinal fluid (CSF) diversion.

Results

We distinguished five lesion types that differ across a range of sac sizes, nerve root stretching, and placode exposure, with 93% agreement between examiners (p<0.001). Fetal characteristics at preoperative evaluation differed significantly by lesion type, including lesion volume (p<0.001), largest ventricle size (p=0.008), tonsillar herniation (p=0.005), and head circumference (p=0.03). Lesion level, talipes, and lower extremities movement did not differ by type. Surgical and perinatal outcomes differed by lesion type, including need for patch skin closure (p<0.001), gestational age at delivery (p=0.01), and NICU length of stay (p<0.001). PPROM, CSF leakage at birth, and CSF diversion in the NICU did not differ between lesion groups. Linear regression associated severity of ventriculomegaly with lesion type, but not with tonsillar herniation level.

Conclusions and Relevance

There is a distinct phenotypic spectrum in open spina bifida with differential baseline presentation and outcomes. Severity of ventriculomegaly is associated with lesion type, rather than tonsillar herniation level. Our findings expand the classification of spina bifida to reveal a spectrum that warrants further study.

Quality of Life of Children Treated for Split Cord Malformation

OBJECTIVE

Split cord malformation (SCM), associated with neurologic deficits, necessitates surgical intervention for spinal cord detethering. Limited evidence exists regarding its impact on children's quality of life. Our study aims to evaluate the postoperative quality of life in children treated for SCM.

METHODS

This retrospective cohort study examined records of patients with SCM operated on between July 1, 2012, and July 31, 2022, at a single center. Data, including Health Utility Index-3 (HUI-3) scores provided by guardians, was collected to assess quality of life. Clinical and neurologic outcomes were also analyzed.

RESULTS

Twenty-five patients, predominantly female (68%), with a median age of 7 years, were included. Most presented with normal motor function (76%). The most common anatomic level of SCM was lumbar (12; 48%) followed by lumbosacral (5; 20%). A bony spur from the lamina was the most common cause of splitting the cord (64%). Over a median follow-up of 3.3 years, 64% of patients showed neurologic stability, 16% showed neurologic improvement, and 4% experienced deterioration. The mean HUI-3 score for 21 children was 0.93 ± 0.24.

CONCLUSIONS

Surgical management of SCM showed favorable neurologic outcomes and a positive long-term quality of life, as shown by HUI-3 scores. Our findings emphasize the efficacy of surgical intervention in improving the lives of children with this condition.

Intracranial volumetric evaluation in postnatally repaired myelomeningocele infants

INTRODUCTION

Most myelomeningocele (MMC) cases present with ventriculomegaly or hydrocephalus, yet a comprehensive volumetric assessment of MMC intracranial structures is lacking. This study aimed to provide baseline data on intracranial structural volumes immediately after birth in MMC infants who underwent repair surgeries after birth (postnatal repair).

METHODS

In this retrospective single-center study, we analyzed 52 MMC infants undergoing postnatal repair, utilizing head computed tomography scans at birth for volumetric assessment. Intracranial volume (ICV), lateral ventricles volume (LVV), choroid plexus volume (CPV), and posterior cranial fossa volume (PCFV) were measured. Hydrocephalus was classified into no hydrocephalus, progressive hydrocephalus, and hydrocephalus at birth. Comparative analysis employed the Wilcoxon rank-sum test. Receiver operating characteristic (ROC) analysis discriminated cases with and without ventriculoperitoneal shunt (VPS).

RESULTS

The median values were 407.50 mL for ICV, 33.18 mL for LVV, 0.67 mL for CPV, and 21.35 mL for PCFV. Thirty-seven cases (71.15%) underwent VPS. ROC analysis revealed an LVV cut-off value of 6.74 mL for discriminating cases with and without VPS. Progressive hydrocephalus showed no significant difference in ICV but significantly larger LVV compared to no hydrocephalus. Hydrocephalus at birth demonstrated statistically larger ICV and LVV compared to the other two types.

CONCLUSION

Baseline volumetric data were provided, and volumetric analysis exhibited statistical differences among three hydrocephalus types. These findings enhance our understanding of intracranial volumetric changes in MMC, facilitating more objective assessments of MMC cases.

Total spine MRI for the preoperative evaluation of adolescent idiopathic scoliosis: Part 2 - spinal cord tumors, dysraphisms, diastematomyelia, and vertebral anomalies

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.

Unveiling the Integral Role of Magnetic Resonance Imaging in the Comprehensive Evaluation and Diagnosis of Spinal Dysraphism

Background Spinal dysraphism, characterized by incomplete closure of neural and bone spinal structures, manifests as congenital fusion abnormalities along the dorsal midline, involving the skin, subcutaneous tissue, meninges, vertebrae, and neural tissue. Magnetic resonance imaging (MRI), the preferred imaging modality for assessing spinal dysraphism across all age groups, provides direct visualization of the spinal cord without the need for contrast or ionizing radiation while also eliminating bone artifacts and allowing multiplanar imaging. The objective of this study was to evaluate the range of spinal dysraphism lesions and assess the significance of MRI in their evaluation. Methodology Thirty patients with suspected spinal dysraphism underwent evaluation at the Medical College Hospital and Study Centre in Vijayapur, India. This cross-sectional observational study included patients diagnosed or provisionally diagnosed with spinal dysraphism based on clinical and imaging profiles. Cases were identified through preliminary findings on radiographs. Results The study encompassed individuals aged one month to 20 years, with the largest proportion of patients (36.67%) falling within the 1-5-year age group. Spina bifida was the most prevalent spinal abnormality, accounting for 70% of cases. In 12 patients (40%), the most prevalent location of involvement was the lumbosacral spine. Conclusion MRI provides excellent tissue differentiation, particularly of lipomatous tissue, with reproducible and comprehensive section planes and relative operator independence. Moreover, MRI is beneficial for children with suspected spinal dysraphism as it can be performed without ionizing radiation, biological risks, or the need for intrathecal contrast media.

Prognostic Significance of Central Skull Base Remodeling in Chiari II Malformation

BACKGROUND AND PURPOSE

Outward convexity of the basiocciput and posterior atlanto-occipital membrane are common in patients with Chiari II malformation associated with an open neural tube defect. We aimed to determine if the severity of these findings correlated with the need for future hydrocephalus treatment.

MATERIALS AND METHODS

A retrospective chart and imaging review identified patients who underwent open neural tube defect repair at a quaternary care pediatric hospital from July 2014 through September 2022. Patients were classified by the need for hydrocephalus treatment and whether they received prenatal or postnatal neural tube defect repair. Measurements of imaging parameters related to posterior fossa maldevelopment and skull base remodeling were performed.

RESULTS

Compared with 65 patients who did not require hydrocephalus treatment, 74 patients who required treatment demonstrated statistically significantly greater mean basiocciput convexity (P < .001). While the mean basiocciput length in the hydrocephalus treatment group was smaller (P < .001), the ratio of basiocciput convexity to length was larger (P < .001). Notably, 100% of patients with a basiocciput convexity of ≥4 mm required hydrocephalus treatment. The mean posterior atlanto-occipital membrane convexity was significantly greater for patients who required hydrocephalus treatment in the postnatal group (P = .02), but not the prenatal group (P = .09).

CONCLUSIONS

Pediatric patients with Chiari II malformation who ultimately required surgical hydrocephalus treatment had greater outward convexity of the basiocciput but had greater posterior atlanto-occipital membrane outward convexity only if the repair was performed postnatally. Together these measurements may be useful in predicting the need for hydrocephalus treatment.

Prenatal diagnosis and postnatal outcome of closed spinal dysraphism

OBJECTIVE

To evaluate the prenatal diagnosis of closed dysraphism (CD) and its correlation with postnatal findings and neonatal adverse outcomes.

METHODS

A retrospective cohort study including pregnancies diagsnosed with fetal CD by prenatal ultrasound (US) and magnetic resonance imaging (MRI) at a single tertiary center between September 2011 and July 2021.

RESULTS

CD was diagnosed prenatally and confirmed postnatally in 12 fetuses. The mean gestational age of prenatal imaging was 24.2 weeks, in 17% the head circumference was ≤fifth percentile and in 25% the cerebellar diameter was ≤fifth percentile. US findings included banana sign in 17%, and lemon sign in 33%. On MRI, posterior fossa anomalies were seen in 33% of cases, with hindbrain herniation below the foramen magnum in two cases. Mean clivus-supraocciput angle (CSA) was 74°. Additional anomalies outside the CNS were observed in 50%. Abnormal foot position was demonstrated prenatally in 17%. Neurogenic bladder was present in 90% of patients after birth.

CONCLUSION

Arnold Chiari II malformation and impaired motor function can be present on prenatal imaging of fetuses with CD and may be associated with a specific type of CD. Prenatal distinction of CD can be challenging. Associated extra CNS anomalies are frequent and the rate of neurogenic urinary tract dysfunction is high.

Multidisciplinary management of people with spina bifida across the lifespan

The average worldwide prevalence of neural tube defects (NTDs) is 1.0 per 1000 births. Its development is multifactorial due to genetic and non-genetic factors. Spina bifida (SB) is one of main representatives of NTD. The spinal cord lesion level is the main determinant of the level of paralysis, numbness, and difficulties with bladder/bowel functions. Myelomeningocele prenatal repair reduces hydrocephalus and hindbrain herniation and improves motor function. The severity of hydrocephalus is associated with poorer neurodevelopmental outcomes whether operated on prenatally or after birth. People with SB tend to have a lower IQ and cognitive difficulties. Early diagnosis, proactivity, and lifelong multidisciplinary follow-up are key protective issues. Invasive urological interventions should be considered in selected patients after failure of conservative treatment. Transition to adult care should be well planned as it is challenging. Health literacy is directly associated with success at transition. Sexuality and fertility should be addressed before/during puberty. Overall, the rates of fecal and urinary continence and skin breakdown increase with age, whereas the ability to ambulate declines with age. Bowel and urinary incontinence are independent predictors of lower health-related quality of life (HRQoL) in adults with SB. Bowel incontinence has negative impact on HRQoL regardless of frequency or amount. Long-term caregiver support should be offered at diagnosis. Survival at a mean of 50 years is poor, at 32%, due to central nervous system deaths, cancer, urological disease, and sepsis. Challenges to implementation of recommended practices exist, especially in low and middle-income countries.

It Looks Like a Spinal Cord Tumor but It Is Not

Differentiating neoplastic from non-neoplastic spinal cord pathologies may be challenging due to overlapping clinical and radiological features. Spinal cord tumors, which comprise only 2-4% of central nervous system tumors, are rarer than non-tumoral myelopathies of inflammatory, vascular, or infectious origins. The risk of neurological deterioration and the high rate of false negatives or misdiagnoses associated with spinal cord biopsies require a cautious approach. Facing a spinal cord lesion, prioritizing more common non-surgical myelopathies in differential diagnoses is essential. A comprehensive radiological diagnostic approach is mandatory to identify spinal cord tumor mimics. The diagnostic process involves a multi-step approach: detecting lesions primarily using MRI techniques, precise localization of lesions, assessing lesion signal intensity characteristics, and searching for potentially associated anomalies at spinal cord and cerebral MRI. This review aims to delineate the radiological diagnostic approach for spinal cord lesions that may mimic tumors and briefly highlight the primary pathologies behind these lesions.

Ambulation after in-utero fetoscopic or open neural tube defect repair: predictors for ambulation at 30 months

OBJECTIVES

To compare the ambulatory status of a cohort of children who had undergone prenatal repair of an open neural tube defect (ONTD) using one of two different methods (fetoscopic or open hysterotomy) with that of a cohort who had undergone postnatal repair, and to identify the best predictors of ambulation at 30 months of age.

METHODS

This was a retrospective review of a cohort of children who underwent ONTD repair either prenatally (n = 110), by fetoscopic surgery (n = 73) or open hysterotomy surgery (n = 37), or postnatally (n = 51), in a single tertiary hospital between November 2011 and May 2023. The cohort comprised a consecutive sample of cases who had undergone ONTD repair in-utero following Management of Myelomeningocele Study (MOMS) trial criteria and cases who had undergone postnatal repair, meeting the same criteria, which were also followed up after birth at the same institution. Motor function assessment by ultrasound was recorded at referral, 6 weeks after prenatal repair, or after referral in postnatally repaired cases, and at the last ultrasound scan before delivery. Clinical examinations to assess motor function at birth and at 12 months were retrieved from records. Intact motor function was defined as first sacral myotome (S1) motor function. Ambulatory status data at each follow-up visit were collected. The proportion of children who were able to walk independently after 30 months of age was compared between those who had undergone fetoscopic vs open prenatal surgery and between prenatal (by either fetoscopic or open surgery) and postnatal ONTD repair. Logistic regression analyses were performed to identify predictors for independent ambulation.

RESULTS

After 30 months, the proportion of infants who were able to walk independently was higher in prenatally vs postnatally repaired cases (51.8% vs 15.7%, P < 0.01), and there was no difference between those with fetoscopic (52.1%) vs open (51.4%) prenatal repair (P = 0.66). In the prenatally repaired group, having intact motor function at 12 months (adjusted odds ratio (aOR), 9.14 (95% CI, 2.64-31.63), P < 0.01) and at birth (aOR, 4.50 (95% CI, 1.21-16.80), P = 0.02) were significant predictors of independent walking at 30 months; an anatomical level of lesion below L2 at referral (aOR, 1.83 (95% CI, 1.30-2.58), P = 0.01) and female gender (aOR, 3.51 (95% CI, 1.43-8.61), P < 0.01) were also predictive for this outcome.

CONCLUSIONS

Prenatally repaired cases of ONTD have a better chance of being able to walk independently at 30 months than do those who undergo postnatal repair. In patients with prenatally repaired ONTD, ambulatory status at 30 months can be predicted by observing a low lesion level at referral (below L2) and intact motor function postnatally. These results have implications for parental counseling and planning for supportive therapy in pregnancies affected by ONTD. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Functional analysis of germline VANGL2 variants using rescue assays of vangl2 knockout zebrafish

Developmental studies have shown that the evolutionarily conserved Wnt Planar Cell Polarity (PCP) pathway is essential for the development of a diverse range of tissues and organs including the brain, spinal cord, heart and sensory organs, as well as establishment of the left-right body axis. Germline mutations in the highly conserved PCP gene VANGL2 in humans have only been associated with central nervous system malformations, and functional testing to understand variant impact has not been performed. Here we report three new families with missense variants in VANGL2 associated with heterotaxy and congenital heart disease p.(Arg169His), non-syndromic hearing loss p.(Glu465Ala) and congenital heart disease with brain defects p.(Arg135Trp). To test the in vivo impact of these and previously described variants, we have established clinically-relevant assays using mRNA rescue of the vangl2 mutant zebrafish. We show that all variants disrupt Vangl2 function, although to different extents and depending on the developmental process. We also begin to identify that different VANGL2 missense variants may be haploinsufficient and discuss evidence in support of pathogenicity. Together, this study demonstrates that zebrafish present a suitable pipeline to investigate variants of unknown significance and suggests new avenues for investigation of the different developmental contexts of VANGL2 function that are clinically meaningful.

Prenatal Diagnosis and Outcomes of Cervical Meningocele and Myelomeningocele

Prenatal diagnosis of myelomeningocele remains challenging for obstetricians, ultrasonographers, and radiologists, although the increased maternal serum alpha-fetoprotein level aids in the confirmative diagnosis. Fetal cervical myelomeningocele and meningocele are very rare and unique types of myelomeningocele. Prenatal diagnosis of cervical myelomeningocele and meningocele should include the differential diagnosis and association of many intracranial and spino-skeletal pathogenetic variants and genetic diseases, including subependymal nodular heterotopia and Klippel-Feil syndrome. In this report, a comprehensive review of fetal cervical myelomeningocele with its prenatal diagnosis and long-term outcomes is presented.

Chaotic lipoma with proximal syrinx -a (not so) rare variant - review of the literature, possible embryology and management

Chaotic lipomas are an extremely rare variant of spinal lipomas. This entity was first defined in 2009 by Pang and colleagues. Not much has been written about this variant. Its characteristic is the haphazard distribution of DREZ (Dorsal root entry zone), nerve roots and placode-lipoma interface. Thus complete/near-total excision of this lesion is quite difficult. We describe a case of chaotic spinal lipoma and elucidate the challenges faced in the management of this entity and review the literature. We performed a thorough systematic review with the keyword 'chaotic', 'Lipomyelomeningocele', 'Complex Lipomyelomeningocele', 'LMMC', 'Lumbar lipoma', 'spinal lipoma' in the google scholar and PUBMED data system for indexed literature on the above topic with no particular time frame. The studies quoted range earliest from 1970 till currently. Additional potential relevant articles were further retrieved through a manual search of references from original reports. Out of 42 studies, a total of 21 publications were selected which could have encountered a chaotic variant, but due to the term introduced only recently in 2009, may have been described differently. Studies encompassing true lipomeningomyelocele were excluded from our review. What we found out? Chaotic lipoma may not be a new entity. The scarce description in literature may be in part due to non-introduction and unclear description of this term earlier. The management of this variant is particularly challenging with basic principles remaining the same. Meticulous near-total excision and placode-lipoma construct are the major obstacles.

Update on Pediatric Spine Imaging

The spine is often difficult to evaluate clinically in children, increasing the importance of diagnostic imaging to detect a wide variety of spinal disorders ranging from congenital abnormalities to severe infections. Clinical history and physical examination can help determine whether imaging is needed and which imaging technique would be best. The most common cause for back pain, even in children, is muscular strain/spasm that does not require any imaging. However, red flags such as pain at age < 5 years, constant pain, night pain, radicular pain, pain lasting > 4 weeks, or an abnormal neurologic examination may require further investigation. Imaging can be of great value for diagnosis but must be interpreted along with the clinical history, physical examination, and laboratory findings to achieve an accurate diagnosis. We discuss imaging for the most common and/or important spine pathologies in children: congenital and developmental pathologies, trauma, infectious processes, inflammatory causes, and tumors.

Complex Closed Spinal Dysraphism Presenting As Cauda Equina Syndrome With Faun Tail Nevus

A posterior midline cutaneous lesion known as a faun tail nevus or aberrant lumbar hypertrichosis is significant to doctors because it may serve as a cutaneous signal for an underlying spinal cord and spine abnormalities. We describe a 17-year-old child who, since infancy, has had excessive hair development over his lumbosacral area. The lower spinal cord was affected by a related spinal abnormality. Clinical evidence was used to make the diagnosis. The patient presented with complaints of asymmetric monoparesis which on clinical examination and radiological investigations was found to be cauda equina syndrome secondary to spina bifida occulta. This case is reported for its clinical importance as patients with spina bifida occulta may show late deterioration.

Cervical Myelocystocele: A One-in-50,000 Congenital Abnormality of the Spinal Cord

Neural tube defects are a group of birth defects that affect the development of the spinal cord and brain. Myelomeningocele is a type of neural tube defect that results in the protrusion of the spinal cord and meninges through a defect in the vertebral column. While myelomeningocele is a relatively rare condition, cervical myelomeningocele is extremely uncommon. The condition can lead to various neurological problems and atrophies and is typically diagnosed in the first trimester of pregnancy using an ultrasound examination. Surgical intervention is typically recommended to repair the affected vertebral column. In this report, we describe the case of a four-month-old baby boy who was diagnosed with a cervical myelocystocele and successfully treated surgically. The patient had an excellent postoperative status, and this case highlights the importance of early diagnosis and intervention in the management of this rare condition.

Assessment of lower limb trophism in fetuses with open spina bifida using fractional thigh volume of three-dimensional ultrasound

OBJECTIVE

To assess the trophism of the lower limbs of fetuses with open spina bifida using fractional thigh volume (TVOL) of three-dimensional (3D) ultrasound.

METHODS

A prospective cross-sectional study was carried out with normal fetuses and with open spina bifida (myelomeningocele and rachischisis) at 26 weeks' gestation. The TVOL (delimitation of five cross-sectional areas of the middle portion of the limb) was evaluated, as well as the subjective assessment of hypotrophy and lower limb movement.

RESULTS

Thirty-one fetuses with open spina bifida, 21 with myelomeningocele and 10 with rachischisis, and 51 normal fetuses were included. There were no significant differences in the TVOL between normal and spina bifida fetuses (p = 0.623), as well as between normal fetuses, with myelomeningocele and with rachischisis (p = 0.148). There was no significant difference in the TVOL of fetuses with spina bifida with or without lower limb hypotrophy (p = 0.148). Fetuses with spina bifida and with lower limb movement had higher TVOL values than fetuses without lower limb movement (p = 0.002).

CONCLUSION

There were no significant differences in the TVOL measurement of normal and spina bifida fetuses (rachischisis and myelomeningocele). Fetuses with spina bifida without spontaneous movement of the lower limbs had lower TVOL values.

[Guidelines on the urological management of the adult patient with spinal dysraphism (spina bifida)]

INTRODUCTION

Improved life expectancy and prenatal screening have changed the demographics of spina bifida (spinal dysraphism) which has presently become a disease of adulthood. Urinary disorders affect almost all patients with spinal dysraphism and are still the leading cause of mortality in these patients. The aim of this work was to establish recommendations for urological management that take into account the specificities of the spina bifida population.

MATERIALS AND METHODS

National Diagnosis and Management Guidelines (PNDS) were drafted within the framework of the French Rare Diseases Plan at the initiative of the Centre de Référence Maladies Rares Spina Bifida - Dysraphismes of Rennes University Hospital. It is a collaborative work involving experts from different specialties, mainly urologists and rehabilitation physicians. We conducted a systematic search of the literature in French and English in the various fields covered by these recommendations in the MEDLINE database. In accordance with the methodology recommended by the authorities (Guide_methodologique_pnds.pdf, 2006), proposed recommendations were drafted on the basis of this literature review and then submitted to a review group until a consensus was reached.

RESULTS

Bladder dysfunctions induced by spinal dysraphism are multiple and varied and evolve over time. Management must be individually adapted and take into account all the patient's problems, and is therefore necessarily multi-disciplinary. Self-catheterisation is the appropriate micturition method for more than half of the patients and must sometimes be combined with treatments aimed at suppressing any neurogenic detrusor overactivity (NDO) or compliance alteration (anticholinergics, intra-detrusor botulinum toxin). Resort to surgery is sometimes necessary either after failure of non-invasive treatments (e.g. bladder augmentation in case of NDO resistant to pharmacological treatment), or as a first line treatment in the absence of other non-invasive alternatives (e.g. aponeurotic suburethral tape or artificial urinary sphincter for sphincter insufficiency; urinary diversion by ileal conduit if self-catheterisation is impossible).

CONCLUSION

Spinal dysraphism is a complex pathology with multiple neurological, orthopedic, gastrointestinal and urological involvement. The management of bladder and bowel dysfunctions must continue throughout the life of these patients and must be integrated into a multidisciplinary context.

Ischemic myelomalacia and closed spinal dysraphism in multiple finishing swine

Ischemic myelomalacia secondary to fibrocartilaginous emboli (FCE) is an idiopathic disease in humans and animals. On the other hand, congenital spinal cord malformations result from neural tube defects in fetal development (ie, spinal dysraphism), with structural anomalies referred to collectively as myelodysplasia. Spinal dysraphisms are frequently accompanied by skin and vertebral abnormalities because of the embryogenic relationship. In this observational case study, we report the pathologic findings of 13, 18- to 24-weeks-old pigs from a large conventional operation that presented with acute paraparesis. Ischemic myelomalacia secondary to FCE was observed in 5 of 13 examined pigs. Congenital spinal cord malformations located between the caudal thoracic and sacral spinal cord were identified in 7 pigs, with structural abnormalities that ranged from diplomyelia/split cord malformation to segmental spinal dysgenesis (myelodysplasia) to caudal agenesis. Concurrent myelomalacia and congenital spinal cord malformations in the same or different sites were noted in 2 pigs. No spinal lesion was observed in 3 pigs. Although gross vertebral abnormalities were not observed herein, intervertebral instability due to minor defects in the articular facets, as well as other unidentified factors, is suspected to contribute high incidence of FCE. It is likely that these congenital malformations were previously underdiagnosed or are possibly new conditions associated with continuous inbreeding and genetic improvement in the modern swine industry.

“Spinal Dysraphism Spectrum: A Novel Protocol-based Approach for Accurate Diagnosis on Imaging”

The spectrum of spinal dysraphism includes various congenital anomalies of the spinal column and spinal cord. Clinical manifestations are varied and range from paraparesis, gastrointestinal, genitourinary, and musculoskeletal anomalies to asymptomatic cases depending on the level and extent of spinal involvement. Magnetic resonance imaging is the gold standard for assessing these complex spinal anomalies. Even for the experienced radiologist, diagnosis can be challenging in complex cases. It is essential to be aware of the normal embryological developmental stages of the spine for an adequate understanding of the complex anatomy, pathogenesis, and cliniconeuroradiological classification of spinal dysraphism, which is necessary for accurately diagnosing each case as a particular pathological entity. In this pictorial essay, we have depicted the stages and process of spinal embryogenesis, cliniconeuroradiological classification, and the imaging spectrum of spinal dysraphism. As the confusing terminologies and the numerous variants can potentially lead to misdiagnosis, we have proposed a step-wise protocol-based imaging approach to analyze each case and arrive at the correct diagnosis systematically. This would be particularly helpful in confusing and difficult cases, as accurate and early diagnosis is crucial for appropriate patient management.

Combining Bone Collagen Material with hUC-MSCs for Applicationto Spina Bifida in a Rabbit Model

Spina bifida is one of the neural tube defects, with a high incidence in human birth defects, which seriously affects the health and quality of life of patients. In the treatment of bone defects, the source of autologous bone is limited and will cause secondary damage to the patient. At the same time, since the bone tissue in animals needs to play a variety of biological functions, its complex structure cannot be replaced by a single material. The combination of mechanical materials and biological materials has become a common choice. Human umbilical cord mesenchymal stem cells (hUC-MSCs) have the advantages of easy access, rapid proliferation, low immunogenicity, and no ethical issues. It is often used in the clinical research of tissue regeneration and repair. Therefore, in this study, we established a spina bifida model using Japanese white rabbits. This model was used to screen the best regenerative repair products for congenital spina bifida, and to evaluate the safety of regenerative repair products. The results showed that the combination of hUC-MSCs with collagen material had better regeneration effect than collagen material alone, and had no negative impact on the health of animals. This study provides a new idea for the clinical treatment of spina bifida, and also helps to speed up the research progress of regenerative repair products.

First Trimester Ultrasound Detection of Fetal Central Nervous System Anomalies

OBJECTIVE

To evaluate the potential of the first-trimester ultrasound (US) features for the detection of central nervous system (CNS) anomalies. Methods/Methodology: This is a prospective one-center three-year study. Unselected singleton pregnant women were examined using an extended first-trimester anomaly scan (FTAS) that included the CNS assessment: the calvaria shape, the septum (falx cerebri), the aspect of the lateral ventricles, the presence of the third ventricle and aqueduct of Sylvius (AS) and the posterior brain morphometry: the fourth ventricle, namely intracranial translucency (IT), brain stem/brain stem-occipital bone ratio (BS/BSOB) and cisterna magna (CM). The spine and underlying skin were also evaluated. The cases were also followed during the second and third trimesters of pregnancy and at delivery. FTAS efficiency to detect major CNS abnormalities was calculated.

RESULTS

We detected 17 cases with CNS major abnormalities in a population of 1943 first-trimester (FT) fetuses, including spina bifida with myelomeningocele, exencephaly-anencephaly, holoprosencephaly, hydrocephaly, cephalocele and Dandy-Walker malformation. The CNS features in the abnormal group are presented. In the second trimester (ST), we further diagnosed cases of corpus callosum agenesis, cerebellar hypoplasia, vein of Galen aneurysm and fetal infection features (ventriculomegaly, intraventricular bands, intraventricular cyst and hyperechoic foci), all declared normal at the FTAS. During the third trimester (TT) scan we identified a massive fetal cerebral haemorrhage absent at previous investigations. We report a detection rate of 72.7% of fetal brain anomalies in the FT using the proposed CNS parameters. The sensitivity of the examination protocol was 72.7%, and the specificity was 100%.

CONCLUSION

A detailed FT CNS scan is feasible and efficient. The majority of cases of major CNS abnormalities can be detected early in pregnancy. The visualization rates of the CNS parameters in the FT are great with short, if any, additional investigation time. FT cerebral disorders such as haemorrhage or infections were missed in the FT even when an extended evaluation protocol was used.

Severe type of segmental spinal dysgenesis with complete disconnection of the spinal cord and vertebra associated with open neural tube defect

Background

Severe type of segmental spinal dysgenesis (SSD) is a rare and complex anomaly in which the spinal cord completely disconnects at the portion of the spinal dysgenesis. Although closed spinal dysraphisms have been associated with SSD, to the best of our knowledge, the association between open neural tube defect (ONTD) and SSD is significantly rare, with only one case being reported to date.

Case Description

We report a case of an infant with severe SSD and a disconnected spinal cord and spinal column at the thoracolumbar junction associated with myelomeningocele (MMC) in the lumbosacral region. The patient presented severe neurological deficits in the legs and impaired bowel function. The spinal column of L1-L3 was absent. The lower spinal segment consisted of neural placode at the L5-S1 level and no connecting structure between the upper and lower spinal cords. A repair surgery for MMC, including cord untethering and dura plasty, was performed. Histopathological findings revealed a neural placode consisting of a neuroglial tissue and leptomeninges.

Conclusion

The management of severe SSD during the perinatal period is more challenging when it is associated with ONTD. We report detailed neuroradiological, intraoperative, and histological findings of such a case and discuss the embryopathogenesis of the associated ONTD and the treatment strategies.

Spinal Dysraphism Presenting as Neuropathic Ulcers: A Case Report of a Delayed Diagnosis

Spinal dysraphism (SD) refers to the abnormal fusion of dorsal midline structures during embryogenesis. It encompasses a variety of congenital spinal defects, ranging from an overt defect in which neural tissue is exposed with no overlying skin (open SD) such as myelomeningoceles to skin-covered malformations (closed or occult SD). A 13-year-old boy presented with recurrent multiple painless ulcers and erosions over the tips of the toes, mainly involving the right foot with hemorrhagic crusts for 5 years. A review of systems revealed back pain, urine incontinence, and numbness in his right knee. He was diagnosed with peripheral neuropathic ulcers and tethered cord syndrome secondary to SD and confirmed by MRI. He underwent cord detethering and lipoma resection as well as expectant therapy with satisfying outcomes. Physicians should consider early diagnosis of SD to avoid later neurological complications of SD (traction and/or pressure on the spinal cord) when infants are presented with such anomalies: MRI, close follow-up, and neurosurgical intervention may be recommended.

Prevalence and risk factors for scoliosis in adults with closed and open spina bifida: A large, cross-sectional study

BACKGROUND

Scoliosis develops in a proportion of children with myelomeningocele; however, little is known about scoliosis in adulthood and in other forms of spina bifida (SB).

OBJECTIVES

The aims of this study were to describe the prevalence of scoliosis and identify risk factors for its development in a large cohort of adults with open and closed SB.

METHODS

This was a cross-sectional study of data from 580 adults with SB attending their first consultation at a French multidisciplinary referral centre for SB. Sex, anatomical location and type of SB (open or closed), neurological level, back pain and ambulatory status (new Functional Ambulation Classification [new FAC]) were compared in adults with and without scoliosis. These characteristics were used to determine scoliosis risk factors.

RESULTS

In total, 331 adults fulfilled the inclusion criteria: 221 had open and 110 had closed SB. Of these, 176 (53%) had scoliosis: 57% open and 45% closed SB. As compared with individuals without scoliosis, those with scoliosis more frequently had open SB (p=0.03), more cranially located SB (p<0.0001), more severe neurological deficits (p≤0.02) and poorer walking ability (mean new FAC score 3.5 [SD 3.3] vs 6.1 [2.6], [p<0.0001]). In total, 69% had chronic back pain, with no difference in frequency between those with and without scoliosis. The odds of scoliosis was associated with asymmetrical motor level and a new FAC score <4 (odds ratio 0.46, p<0.006, and 0.75, p<0.0001, respectively).

CONCLUSION

About half of adults with open and closed SB had scoliosis. Back pain was frequent in those both with and without scoliosis. Individuals with low walking ability and an asymmetrical motor level should be monitored early and continuously to limit the consequences of scoliosis during their lifetime. A major issue is to determine how scoliosis evolves and to determine appropriate monitoring and treatment strategies for individuals at risk.

Prenatal intracranial hypotension syndrome in congenital cephalocele: Insights into pathophysiologic mechanisms and importance of defect coverage

OBJECTIVE

To compare specific fetal cranial and cerebral findings indicative of prenatal intracranial hypotension (PICH) syndrome between open and closed cephaloceles.

METHODS

Two groups of fetuses with cephalocele who underwent magnetic resonance imaging scan were selected based on the defect coverage: covered ("closed cephalocele" group, n = 4) and uncovered by skin ("open cephalocele" group, n = 8). The presence of signs associated with PICH syndrome was evaluated and findings compared between groups.

RESULTS

Cases from the open cephalocele group showed statistically significant differences in comparison with the closed cephalocele group regarding reduction of the interpeduncular angle (p = 0.006), reduced amount of cerebrospinal fluid in the subarachnoid space (p = 0.01), collapsed/severely reduced fourth ventricle (p = 0.03), cephalocele content (p = 0.03), and identification of a vector traction (p = 0.03). There were no differences in the presence of cerebellar tonsillar descent, obstructive ventriculomegaly, and presence of the lemon sign. In comparison with gestational age-matched controls, only the biparietal diameter but not the head circumference was significantly smaller in both the open and closed cephalocele groups (p < 0.05).

CONCLUSION

Congenital cephaloceles present distinct imaging behavior depending on the defect coverage. Therefore, the classification of cephalocele should include, in addition to location and content, the presence or absence of skin fully covering the defect.

Association between ambulatory skills and diffusion tensor imaging of corpus callosal white matter in infants with spina bifida

OBJECTIVES

To assess brain white matter using diffusion tensor imaging (DTI) at 1 year of age in infants diagnosed with open neural tube defect (ONTD) and explore the association of DTI parameters with ambulatory skills at 30 months of age.

METHODS

Magnetic resonance imaging (MRI) was performed at an average of 12 months of age and included an echo planar axial DTI sequence with diffusion gradients along 20 non-collinear directions. TORTOISE software was used to correct DTI raw data for motion artifacts, and DtiStudio, DiffeoMap and RoiEditor were used for further postprocessing. DTI data were analyzed in terms of fractional anisotropy (FA), trace, radial diffusivity and axial diffusivity. These parameters reflect the integrity and maturation of white-matter motor pathways. At 30 months of age, ambulation status was evaluated by a developmental pediatrician, and infants were classified as ambulatory if they were able to walk independently with or without orthoses or as non-ambulatory if they could not. Linear mixed-effects method was used to examine the association between study outcomes and study group. Possible confounders were sought, and analyses were adjusted for age at MRI scan and ventricular size by including them in the regression model as covariates.

RESULTS

Twenty patients with ONTD were included in this study, including three cases that underwent postnatal repair and 17 cases that underwent prenatal repair. There were five ambulatory and 15 non-ambulatory infants evaluated at a mean age of 31.5 ± 5.7 months. MRI was performed at 50.3 (2-132.4) weeks postpartum. When DTI analysis results were compared between ambulatory and non-ambulatory infants, significant differences were observed in the corpus callosum (CC). Compared with non-ambulatory infants, ambulatory infants had increased FA in the splenium (0.62 (0.48-0.75) vs 0.41 (0.34-0.49); P = 0.01, adjusted P = 0.02), genu (0.64 (0.47-0.80) vs 0.47 (0.35-0.61); P = 0.03, adjusted P = 0.004) and body (0.55 (0.45-0.65) vs 0.40 (0.35-0.46), P = 0.01, adjusted P = 0.01). Reduced trace was observed in the CC of ambulatory children at the level of the splenium (0.0027 (0.0018-0.0037) vs 0.0039 (0.0034-0.0044) mm² /s; P = 0.04, adjusted P = 0.03) and genu (0.0029 (0.0020-0.0038) vs 0.0039 (0.0033-0.0045) mm² /s; P = 0.04, adjusted P = 0.01). In addition, radial diffusivity was reduced in the CC of the ambulatory children at the level of the splenium (0.00057 (0.00025-0.00089) vs 0.0010 (0.00084-0.00120) mm² /s; P = 0.02, adjusted P = 0.02) and the genu (0.00058 (0.00028-0.00088) vs 0.0010 (0.00085-0.00118) mm² /s; P = 0.02, adjusted P = 0.02). There were no differences in axial diffusivity between ambulatory and non-ambulatory children.

CONCLUSION

This study demonstrates a significant association between white matter integrity of connecting fibers of the corpus callosum, as assessed by DTI, and ambulatory skills at 30 months of age in infants with ONTD. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Imaging of Congenital Spine Malformations

Congenital malformations of the spine and spinal cord are a large and diverse group of diagnoses, which are often broadly referred to as spinal dysraphisms (SDs). Derived from the Greek words dys (bad) and raphe (suture), the term dysraphism describes missteps in the process of forming a midline seam during the zipper-like fusion of the neural folds in primary neurulation. As such, the term "spinal dysraphism" is a designation that should technically be reserved for malformations resulting from aberrations in primary neurulation. In medical practice, however, it is a catch-all designation regularly used to describe any of the numerous abnormalities demonstrating incomplete midline closure of mesenchymal, osseous, and nervous tissue, occurring at any point during embryologic development. For the sake of clarity and completeness, this article will also include that breadth in the discussion of congenital abnormalities of the spine.

Avoiding the antenatal counselling faux pas: bridging the gap between prenatal prognostication and postnatal outcome of closed spina bifida

PURPOSE

Closed spina bifida (CSB) is rare in prenatal literature, and various lesions are grouped under this broad nosological entity CSB, leading to confusing and misleading prognostic conclusions.

METHODS

This is a retrospective observational cohort study of prenatally detected CSB cases using two-dimensional ultrasound, complemented by three-dimensional ultrasonography and foetal MRI in indicated cases, from October 2014 to October 2021 in a tertiary-level single centre.

RESULTS

The most common upper vertebral level of CSB was lumbar in 66.6% (10/15). The sub-classification of lesions based on prenatal ultrasound showed an agreement in 53% of the cases. Sixty percent had associated abnormalities identified postnatally, the most common being anorectal malformation seen in 33.3%. On postnatal follow-up, 46.6% had bowel incontinence and bladder dysfunction, and 33.3% developed lower limb deformities.

CONCLUSIONS

All CSBs do not have a uniformly favourable prognosis. The prognosis of CSB depends on the pathological type, the presence of associated abnormalities and the management.

Incidental Sacral Meningocele in an Elderly Patient Diagnosed After Epidermal Inclusion Cyst Removal: A Case Report

A meningocele is a congenital neural tube defect, and the majority of the meningocele cases are identified perinatally. We present the case of a 67-year-old patient with a sacral meningocele undiagnosed until the removal of a symptomatic epidermal inclusion cyst adjacent to it. Cerebrospinal fluid leakage occurred due to an incision in an undiagnosed meningocele adjacent to the epidermal inclusion cyst. Repair of the cerebrospinal fluid leakage was performed successfully without any deficit. The present case underscores the importance of considering a meningocele as a differential diagnosis for a mass occurring in the midline of the back at any age.

Value of pre- and postnatal magnetic resonance imaging in the evaluation of congenital central nervous system anomalies

Fetal MRI and neonatal MRI of the central nervous system (CNS) are complementary tools that can help to accurately counsel and direct the management of children with anomalies of the central nervous system. Postnatal MRI can add to fetal MRI by allowing for monitoring of changes in the severity of disease, better delineation of a suspected prenatal anomaly, evaluation for secondary pathologies related to the primary diagnosis, and surgical management direction. In this review we discuss the roles of fetal and neonatal MRI in the diagnosis and treatment of congenital anomalies of the CNS through a series of case examples and how both are important in patient management.

Sagittal spinopelvic alignment in tethered cord syndrome and split cord malformation

PURPOSE

Sagittal imbalance is common in degenerative and congenital spinal diseases. Some studies have examined spinal deformities in the spina bifida. However, sagittal spinopelvic parameters in tethered cord syndrome (TCS) and split cord malformation (SCM) have been poorly evaluated in the literature. In this study, we investigated sagittal spinopelvic differences in TCS due to fatty filum terminale and SCM patients.

MATERIAL AND METHODS

A total of 78 patients with spina bifida occulta (30 SCM and 48 TCS due to fatty filum terminale) were included in the study. Radiological images of these patients were retrospectively evaluated. We evaluated the pelvic incidence, pelvic tilt, sacral slope, sagittal vertical axis (SVA), T1 pelvic angle, lumbar lordosis (LL), thoracic kyphosis, thoracolumbar alignment, and change in those parameters with age.

RESULTS

Correlation coefficients between age and LL, T1 pelvic angle, and the SVA in patients with TCS due to fatty filum terminale were statistically significant. In addition, correlation coefficients between age and LL and the SVA in patients with SCM were statistically significant. Notably, LL was increased at a statistically significant level with age in patients with TCS and SCM.

CONCLUSION

Improved knowledge of spinal balance parameters in patients with TCS and SCM may be helpful in understanding the clinical course of these pathologies, and provide information regarding the success of surgery at the follow-up period.

Early prenatal diagnosis of an atypical phenotype of sacral spina bifida

Neural tube defects (NTDs) occur during embryogenesis, specifically during the fifth or sixth week of gestation, and are described as aberrant neural tube closing. The defect may alter the normal development of the vertebrae, spinal cord, cranium, or brain. The present study describes the case of a 41-year-old pregnant woman with fetal sacral meningocele, no associated pathologies, no family history of neural tube defects, a pregnancy under folate supplementation with the aim of highlighting the importance of ultrasound in diagnosing neural tube defects. The ultrasonographic diagnosis was not clear from the beginning. In our case, the differential diagnosis of meningocele was made with the cystic compound of a sacrococcygeal teratoma, which represents one of the most common congenital tumors in newborns. The particularity of this case was that a neural tube defect occurred despite the prophylactic administration of folic acid during pregnancy, which represents a well-documented protection against neural tube defects in fetuses.

Spinal Dysraphisms: A New Anatomical–Clinicoradiological Classification

Background Spinal dysraphisms refer to the congenital abnormalities of the spine and spinal cord due to aberrations in the processes of gastrulation, primary neurulation, and secondary neurulation. Embryology of many complex spinal dysraphisms are yet poorly understood and there is no agreeable anatomical–clinicoradiological classification with inclusion of recently documented and complex spinal dysraphisms.

Aims and Objectives The main objective of this study was to review the imaging features of spinal dysraphisms with a better understanding of embryological abnormalities and propose a new classification inclusive of all complex and unusual dysraphisms based on anatomical and clinicoradiological correlation.

Materials and Methods This was a retrospective single institutional observational study of 391 cases of spinal dysraphism for 10 years in our institution. Of 391 cases included in the study, 204 were males and 187 were females. Also, 123 cases belonged to the 0–6 months age group, 38 cases belonged to the 7–12 months age group, 156 belonged to the 1–5 years age group, 39 cases belonged to the 6–10 years age group, and 35 cases belonged to 10–20 years age group.

Results An anatomical–clinicoradiological analysis of cases yielded a high proportion of cases of spinal lipomas, including lipomyeloceles and lipomyelomeningoceles (31.3%) and posterior myelomeningocele (14.2%). Anterior myelocoele (0.2%), sacral chordoma(0.2%), and intrasacral meningocele (0.2%) formed the least proportion of cases. A new classification was proposed based on the analysis of acquired data.

Conclusion A structured approach in imaging spinal dysraphism is necessary for imaging evaluation in recent years. The proposed new classification based on clinicoradiological correlation and anatomic location is inclusive of unusual and complex dysraphisms.

Treatment of spinal deformity with diastematomyelia type I: one-stage, two-stage surgery and new technique (vertebral column resection through wide bony septum)

STUDY DESIGN

Case series, literature review, and technical note.

OBJECTIVES

To compare two different approaches to treat the spinal deformity with split cord malformation type I (SCM I). To present a new method of one-stage surgical treatment of congenital spinal deformity with wide bony septum (SCM I).

METHODS

Analysis of the literature on the different types of combined surgical treatment of spinal deformities with SCM I was performed. We have provided our own data on 27 patients treated for congenital spinal deformity and SCM I, one of which underwent Schwab IV type osteotomy at the apex of the deformity through the bony septum and pedicles. Inclusion criteria were presence of spinal deformity in combination with SCM 1, performed surgery to correct spinal deformity, and follow-up period of at least 2 years.

RESULTS

The result of the literature review was controversial and requires additional research. The average age of patients was 8.8 ± 6.6 years old. One-stage treatment of SCM I and spinal deformity was performed in 10 patients (group I) and two-stage in 14 patients (group II). Three patients with severe myelodysplasia, SCM I, and congenital kyphoscoliosis underwent correction of spinal deformity without SCM I removing (group III). The group I had the longest surgery duration (mean 289 ± 75 min) and largest blood loss (mean 560 ± 386 ml), a high percentage of deformity correction (mean 69.6%), and the highest rate of complications (60%). The most optimal was the two-stage treatment with the mean surgery duration 191 ± 137 min, mean blood loss 339 ± 436 ml, mean correction rate 63%, and frequency of complications 21%. The average follow-up time was 6.0 ± 2.6 years.

CONCLUSIONS

One stage surgery associated with a large surgical invasion and a large number of complications. It can be used in some cases, for example when the wide bony septum (SCM I) is localized at the apex of the congenital scoliosis or kyphosis. In all other cases, it is worth adhering to a two-stage treatment. Many new works demonstrate the relative safety and effectiveness of deformity correction without removing the SCM. In our opinion, indications for treatment of spinal deformity without SCM I removing can be the need to perform a shortening ostetomy outside the SCM zone. The remaining cases require a thorough assessment and a balanced decision.

Imaging Review of Obstetric Sequelae of Maternal Diabetes Mellitus

Diabetes mellitus, whether preexisting or gestational, poses significant risk to both the mother and the developing fetus. A myriad of potential fetal complications in the setting of diabetic pregnancies include, among others, congenital anomalies, delayed fetal lung maturity, macrosomia, and increased perinatal morbidity and mortality. Congenital anomalies most commonly involve the nervous, cardiovascular, genitourinary, and musculoskeletal systems. Delayed fetal lung maturity, probably secondary to hyperglycemia suppressing surfactant secretion, is a major determinant of perinatal morbidity and mortality. Besides the potential complications encountered during cesarean delivery in macrosomic fetuses, vaginal delivery is also associated with increased risks of shoulder dystocia, clavicular and humeral fractures, and brachial plexus palsy. Maternal complications are related to the increased risk of hypertensive diseases of pregnancy and associated preeclampsia and hemolysis, elevated liver function, and low platelets (HELLP) syndrome, as well as complications encountered at the time of delivery secondary to fetal macrosomia and cesarean delivery. Additional conditions encountered in the setting of maternal diabetes include polyhydramnios, placental thickening, and two-vessel umbilical cord, each of which is associated with adverse fetal and maternal outcomes including fetal growth restriction, preterm labor, placental abruption, and premature rupture of membranes. Imaging plays a vital role in the evaluation of the mother and the fetus and can provide invaluable information that can be used by maternal fetal medicine to manage this patient population effectively. The authors review the pathophysiologic alterations induced by diabetes in pregnancy, discuss the imaging spectrum of diabetic embryopathy, and provide a detailed review of potential associated maternal complications. Online supplemental material is available for this article. ^©RSNA, 2021.

The Myelic Limited Dorsal Malformation: Prenatal Ultrasonographic Characteristics of an Intermediate Form of Dysraphism

OBJECTIVES

The aim of the study was to report a subtype of dysraphism designated as myelic limited dorsal malformation (MyeLDM) and to describe its characteristics at prenatal ultrasound (US).

METHODS

It was a retrospective study from 2014 to 2020 based on second-line US evaluation of patients referred to our institution for myelomeningocele (MMC). Magnetic resonance imaging and acetylcholine esterase evaluation in the amniotic fluid were also offered. Major and minor criteria for open and closed dysraphism were defined and recorded for each patient. Patients were included as MyeLDM when both criteria of closed and open dysraphism were observed in the same fetus. Correlations were obtained with the postpartum data.

RESULTS

Twenty patients fulfilled the inclusion criteria, some of them being very close to MMC, others very close to limited dorsal myeloschisis (LDM), and others lying in between. There were 13 live-born neonates and 7 terminations of pregnancy. Correlations between prenatal and postpartum data were overall very good.

CONCLUSION

Our series describe the ultrasonographic characteristics of an intermediate type of dysraphism and suggest that there is a continuum between MMC and LDM with numerous possibilities of hybrid forms (MyeLDM) sharing characteristics of both open and closed dysraphisms.

[Research progress on the etiology and pathogenesis of spina bifida]

Objective

To review the research progress on etiology and pathogenesis of spina bifida.

Methods

By consulting relevant domestic and foreign research literature on spina bifida, the classification, epidemic trend, pathogenesis, etiology, prevention and treatment of it were analyzed and summarized.

Results

Spina bifida, a common phenotype of neural tube defects, is classified based on the degree and pattern of malformation associated with neuroectodermal involvement and is due to the disturbance of neural tube closure 28 days before embryonic development. The prevalence of spina bifida varies greatly among different ethnic groups and regions, and its etiology is complex. Currently, some spina bifida patients can be prevented by folic acid supplements, and with the improvement of treatment technology, the short-term and long-term survival rate of children with spina bifida has improved.

Conclusion

The research on the pathogenesis of spina bifida will be based on the refined individual information on exposure, genetics, and complex phenotype, and will provide a theoretical basis for improving prevention and treatment strategies through multidisciplinary cooperation.

Multimodality Imaging Evaluation of Fetal Spine Anomalies with Postnatal Correlation

Congenital anomalies of the spine are associated with substantial morbidity in the perinatal period and may affect the rest of the patient's life. Accurate early diagnosis of spinal abnormalities during fetal imaging allows prenatal, perinatal, and postnatal treatment planning, which can substantially affect functional outcomes. The most common and clinically relevant congenital anomalies of the spine fall into three broad categories: spinal dysraphism, segmentation and fusion anomalies of the vertebral column, and sacrococcygeal teratomas. Spinal dysraphism is further categorized into one of two subtypes: open spinal dysraphism and closed spinal dysraphism. The latter category is further subdivided into those with and without subcutaneous masses. Open spinal dysraphism is an emergency and must be closed at birth because of the risk of infection. In utero closure is also offered at some fetal centers. Sacrococcygeal teratomas are the most common fetal pelvic masses and the prognosis is variable. Finally, vertebral body anomalies are categorized into formation (butterfly and hemivertebrae) and segmentation (block vertebrae) anomalies. Although appropriate evaluation of the fetal spine begins with US, which is the initial screening modality of choice, MRI is increasingly important as a problem-solving tool, especially given the recent advances in fetal MRI, its availability, and the complexity of fetal interventions. Online supplemental material is available for this article. ^©RSNA, 2021.

Hydrocephalus in myelomeningocele

PURPOSE

To investigate certain aspects of hydrocephalus in patients with myelomeningocele.

METHODS

We retrospectively analyzed data of 1050 patients with myelomeningocele who underwent surgical treatment between June 1991 and June 2021. These patients were divided into three groups: group 1 consisted of patients who underwent surgery after the first 6 h of life, group 2 consisted of patients who underwent surgery within the first 6 h, and group 3 consisted of patients who underwent surgery during the fetal period and before 26 6/7 weeks of gestation.

RESULTS

There were 125, 590, and 335 patients in groups 1, 2, and 3, respectively. In groups 1 and 2, 593 (83%) patients developed hydrocephalus after birth and required ventriculoperitoneal shunt placement in the maternity ward, mainly within the first 4 days of life. In contrast, in group 3, 24 (7.2%) patients required surgery to treat hydrocephalus after birth. Hydrocephalus was the primary cause of mortality in groups 1 and 2, with mortality rates of 35% and 10%, respectively. In group 3, the mortality rate was 0.8% and was not related to hydrocephalus.

CONCLUSION

The onset of hydrocephalus is directly related to myelomeningocele closure in neurosurgery.

Split Cord Malformation in a Thoroughbred Horse

We report a 9-year-old Thoroughbred gelding that had sudden onset lameness of the right forelimb with episodes of lateral decubitus and generalized pain after completion of a normal training session. The clinical signs subsequently became less pronounced with only mild right forelimb lameness. However, after further orthopaedic examination, it developed severe, acute ataxia and paraplegia, the Schiff-Sherrington phenomenon and risus sardonicus. At necropsy, a partial duplication of the cervical spinal cord was identified, consistent with split spinal cord malformation type II or diplomyelia. However, the clinical significance of this finding is not clear.

Pediatric Spinal Cord Diseases

Spinal cord diseases in pediatric patients are highly variable in terms of presentation, pathology, and prognosis. Not only do they differ with respect to each other but so too with their adult equivalents. Some of the most common diseases are autoimmune (ie, multiple sclerosis, acute disseminated encephalomyelitis, and acute transverse myelitis), congenital (ie, dysraphism with spina bifida, split cord malformation, and tethered cord syndrome), tumor (ie, juvenile pilocytic astrocytoma, ependymoma, and hem-angioblastoma), and vascular (ie, cavernous malformations, arteriovenous malformations, and dural arteriovenous fistulas) in nature. These each require their own niche treatment paradigm and prognosis. Furthermore, presentation of different spinal cord diseases in children can be difficult to discern without epidemiologic and imaging data. Interpretation of these data is crucial to facilitating a timely and accurate diagnosis. Correspondingly, the aim of this review was to highlight the most pertinent features of the most common spinal cord diseases in the pediatric population.

Cutaneous Stigmata of the Spine: A Review of Indications for Imaging and Referral

Cutaneous stigmata of the midline spine are a common question in pediatrics. They are known to be related to a higher likelihood of underlying dysraphic spinal abnormalities. Clear understanding of different types of cutaneous stigmata and correlating dysraphic findings can aid in appropriate imaging workup and timely management of patient pathology. In this article, the authors review midline spinal cutaneous findings in the pediatric population with occult spinal dysraphism.

Neonatal and infantile spinal sonography: A useful investigation often underutilized

Sonography is an ideal, effective, noninvasive tool for evaluation of the spinal cord in neonatal and early infantile age groups owing to lack of ossification of the posterior elements of spine. Understanding normal anatomical appearances is a prerequisite for the interpretation of various pathologies of the spinal canal and its contents. This review elucidates normal appearances of the spinal cord in this age group, in both axial and sagittal planes. Usefulness of Doppler sonography is briefly discussed, and special emphasis is placed on normal anatomical variants that may mimic spinal abnormalities. Sonographic appearances of common intraspinal pathologies, both congenital and acquired, are exhaustively described. Key points regarding sonographic diagnosis of important spinal anomalies are emphasized and explained in detail. To conclude, spinal ultrasound is a reliable and widely available screening tool, albeit the usefulness of which is often underestimated.

Spinal dysraphism illustrated; Embroyology revisited

Spinal cord development occurs through three consecutive periods of gastrulation, primary nerulation and secondary neurulation. Aberration in these stages causes abnormalities of the spine and spinal cord, collectively referred as spinal dysraphism. They can be broadly classified as anomalies of gastrulation (disorders of notochord formation and of integration); anomalies of primary neurulation (premature dysjunction and nondysjunction); combined anomalies of gastrulation and primary neurulation and anomalies of secondary neurulation. Correlation with clinical and embryological data and common imaging findings provides an organized approach in their diagnosis.

Impact of the cystic neural tube defects on fetal motor function in prenatal myelomeningocele repairs: A retrospective cohort study

OBJECTIVE

To determine the impact of the lesion type (cystic [myelomeningocele] or flat [myeloschisis]) on the fetal motor function (MF) in cases candidates for prenatal open neural tube defect (ONTD) repair.

METHODS

Retrospective cohort study of patients with ONTD who underwent prenatal repair at a single institution between 2011 and 2019. The lesion type and the measurements of the length and width of the lesions to calculate the surface of the ellipsoid lesion were performed using MR scans. Prenatal MF of the lower extremities was evaluated by ultrasound following a metameric distribution at the time of referral. Intact MF was defined as the observation of plantar flexion of the ankle. Logistic regression was performed to determine the predictive value of the type of lesion for having an intact MF at the time of referral.

RESULTS

103 patients were included at 22.9 (19-25.4) weeks; 65% had cystic and 35% had flat lesions. At the time of referral, there was a higher proportion of cases with an intact MF in the presence of flat lesions (34/36; 94.4%) as compared to cystic lesion (48/67; 71.6%, p < 0.01). When adjusting for gestational age and anatomical level of the lesion, flat ONTD were 3.1 times more likely to be associated by intact motor function (CI%95 [2.1-4.6], p < 0.01) at the time of referral.

CONCLUSION

Cystic ONTD are more likely to be associated with impaired MF at mid-gestation in candidates for prenatal ONTD repair.

Three-Dimensional Sonographic Evaluation of the Position of the Fetal Conus Medullaris at First Trimester

OBJECTIVE

The objective of this study was to assess the position of the conus medullaris (CM) at the first trimester 3D ultrasound in a cohort of structurally normal fetuses.

METHODS

This was a multicenter prospective study involving a consecutive series of structurally normal fetuses between 11 and 13 weeks of gestation (CRL between 45 and 84 mm). All fetuses were submitted to 3D transvaginal ultrasound using a sagittal view of the spine as the starting plane of acquisition. At offline analysis, the position of the CM was evaluated by 2 independent operators with a quantitative and a qualitative method: (1) the distance between the most caudal part of the CM and the distal end of the coccyx (CMCd) was measured; (2) a line perpendicular to the fetal spine joining the tip of the CM to the anterior abdominal wall was traced to determine the level of this line in relation to the umbilical cord insertion (conus to abdomen line, CAL). Interobserver agreement for the CCMd was evaluated. Linear regression analysis was used to determine the association between the CMCd and CRL, and a normal range was computed based on the best-fit model. The absence of congenital anomalies was confirmed in all cases after birth.

RESULTS

In the study period between December 2019 and March 2020, 143 fetuses were recruited. In 130 fetuses (90.9%), the visualization of the CM was feasible. The mean value of the CMCd was 1.09 ± 0.16 cm. The 95% limits of agreement for the interobserver variability in measurement of the CMCd were 0.24 and 0.26 cm. The interobserver variability based on the intra-class correlation coefficient (ICC) for the CCMd was good (ICC = 0.81). We found a positive linear relationship between the CCMd and CRL. In all these fetuses, the CAL encountered the abdominal wall at or above the level of the cord insertion.

CONCLUSION

In normal fetuses, the assessment of the CM position is feasible at the first trimester 3D ultrasound with a good interobserver agreement. The CM level was never found below the fetal umbilical cord insertion, while the CMCd was noted to increase according to the gestational age, confirming the "ascension" of the CM during fetal life.