Thalamic connectivity topography in newborns with spina bifida: association with neurological functional level but not developmental outcome at 2 years.

Spina bifida affects spinal cord and cerebral development, leading to motor and cognitive delay. We investigated whether there are associations between thalamocortical connectivity topography, neurological function, and developmental outcomes in open spina bifida. Diffusion tensor MRI was used to assess thalamocortical connectivity in 44 newborns with open spina bifida who underwent prenatal surgical repair. We quantified the volume of clusters formed based on the strongest probabilistic connectivity to the frontal, parietal, and temporal cortex. Developmental outcomes were assessed using the Bayley III Scales, while the functional level of the lesion was assessed by neurological examination at 2 years of age. Higher functional level was associated with smaller thalamo-parietal, while lower functional level was associated with smaller thalamo-temporal connectivity clusters (Bonferroni-corrected P < 0.05). Lower functional levels were associated with weaker thalamic temporal connectivity, particularly in the ventrolateral and ventral anterior nuclei. No associations were found between thalamocortical connectivity and developmental outcomes. Our findings suggest that altered thalamocortical circuitry development in open spina bifida may contribute to impaired lower extremity function, impacting motor function and independent ambulation. We hypothesize that the neurologic function might not merely be caused by the spinal cord lesion, but further impacted by the disruption of cerebral neuronal circuitry.

Prenatal ultrasound diagnosis of neural tube defects in the era of intrauterine repair - Eleven years' experiences.

OBJECTIVE: To modify the current neural tube defect (NTD) classification for fetal medicine specialists, and to investigate the impact of prenatal ultrasound conus medullaris position screening on the detection rate of closed spinal dysraphism and pregnancy outcomes. MATERIALS AND METHODS: The clinical data of 112 patients prenatally diagnosed with neural tube defects in Taiji clinic from 2008 to 2018 were retrospectively analyzed. All cases were classified following the modified classification. We compared the detection rate before and after introducing the conus medullaris screening and pregnancy outcomes for NTD types. RESULTS: Closed spinal dysraphism type prevailed in our sample (43.8%). The median gestational age at the time of detection for cranial dysraphism was 13.3 weeks, open spinal dysraphism was 22.0 weeks, and closed spinal dysraphism was 22.6 weeks. All cranial dysraphism (n = 43) and open spinal dysraphism cases (n = 20) had pregnancies terminated. For closed spinal dysraphism Class 1, the live-birth rate was 100.0% in the cases without other anomalies and 33.3% in the cases with other anomalies, respectively (X2 = 17.25, p < 0.001). Similarly, for Class 2, pregnancy continuation rate was 50.0% in cases without other anomalies and 20.0% in cases with other anomalies, yet it failed to reach statistical significance (X2 = 0.9, p = 0.524). CONCLUSION: Our case series may help to improve early screening and prenatal diagnosis of NTDs. Modified classification is adjusted for use in ultrasound fetal care facilities, which could be used for predicting pregnancy outcome. We suggest promoting first-trimester anatomical screening in order to make an earlier diagnosis and therefore provide better prenatal care for open spinal dysraphism cases in the era of intrauterine repair. Our findings imply that the use of fetal conus medullaris position as a marker for closed spinal dysraphism improves the detection rate and would unlikely lead to a higher termination rate.

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.

Diagnosis of spina bifida on ultrasound: always termination?

Open spina bifida is a non-lethal fetal anomaly. Significant advances in the prevention, diagnosis and treatment of open spina bifida have been made over the past 75 years. The most significant strategy for the prevention of open spina bifida has been with folic acid supplementation; however, further investigation into the complicated role that genetics and the environment play in metabolism are coming to light. Ultrasound is the gold standard diagnostic tool for spina bifida. Three-dimensional ultrasound and magnetic resonance imaging are also beginning to play a role in the characterisation of the open spina bifida spinal lesion. Lesion level has been closely correlated to short and long-term outcomes, and prenatal characterisation of lesion level on ultrasound is important for patient counselling. Long-term outcomes of people living with spina bifida are available and should be used for non-directive patient counselling about pregnancy choices for women with open spina bifida.