Prenatally detected myelomeningoceles: sonographic accuracy in estimation of the spinal level

Fetal neurosurgery

Among fetal surgical procedures, neurosurgery stands out due to the number of cases and the possibility of developing new procedures that can be performed in the fetal period. To perform fetal neurosurgical procedures, there is a need for specialized centers that have experts in the diagnosis of fetal pathologies and a highly complex obstetrics service with specialized maternal-fetal teams associated with a pediatric neurosurgery center with expertise in the diverse pathologies of the fetus and the central nervous system that offers multidisciplinary follow-up during postnatal life. Services that do not have these characteristics should refer their patients to these centers to obtain better treatment results. It is essential that the fetal neurosurgical procedure be performed by a pediatric neurosurgeon with extensive experience, as he will be responsible for monitoring these patients in the postnatal period and for several years. The objective of this manuscript is to demonstrate the diagnostic and treatment possibilities, in the fetal period, of some neurosurgical diseases such as hydrocephalus, tumors, occipital encephalocele, and myelomeningocele.

Prenatal screening for neural tube defects: from maternal serum alpha-fetoprotein to ultrasonography

The two main screening tests during pregnancy are those for chromosomal abnormalities and neural tube defects (NTDs). In particular, for NTDs, measurement of maternal serum alpha-fetoprotein (MSAFP) levels early in the second trimester (15-18 weeks of gestation) has been considered the gold standard screening test for the past 4 decades. However, with remarkable technological advancements and the widespread use of ultrasound during those periods, mid-trimester ultrasonography has gradually replaced the role of measuring MSAFP levels as a screening method for NTDs. This change was initiated more about 10 years ago in some countries, which have issued national guidelines to use mid-trimester ultrasonography instead of measuring MSAFP levels as a prenatal screening method for NTDs. However, no significant changes have occurred in Korea, where second-trimester ultrasonography is routinely performed with high-quality equipment. We aimed to provide information regarding the importance of changing the screening method for NTDs from MSAFP measurement to ultrasonography, and to detail methods of implementing mid-trimester ultrasonography for screening purposes. We also share our experience of operating a prenatal diagnostic program for NTDs without using MSAFP for more than 15 years.

Determination of anatomic level of myelomeningocele by prenatal ultrasound

PURPOSE

Ultrasound is the primary method for prenatal identification of myelomeningocele and is critical to prognostication and treatment planning. No study has considered the degree of inaccuracy of prenatal US lesion level estimates and anatomic lesion level on postnatal imaging using the weighted kappa coefficient (κw), nor the impact of maternal BMI on agreement. We examined the accuracy of prenatal ultrasound lesion level estimation in a cohort of patients with myelomeningocele using κw and determined whether BMI influenced accuracy.

METHODS

The study is a retrospective review including patients born 2011-2019 who had prenatal imaging and primary myelomeningocele closure at a single institution. Lesion levels from prenatal ultrasound and postnatal imaging studies were analyzed for agreement at exact level, within 1 level, and within 2 levels using κw. Maternal BMI was examined for correlation with accuracy.

RESULTS

Fifty-seven patients met inclusion criteria. Mean BMI was 31.2. There was no association between maternal BMI and agreement at any level. Lesion level on prenatal ultrasound agreed with postnatal imaging to the exact level in 13 (22.8%) cases, within 1 level in 38 (66.7%) cases, and within 2 levels in 50 (87.7%) cases. Weighted kappa showed moderate agreement at exact level (κ_w = 0.494) and substantial agreement within 1 (κ_w = 0.761) and 2 levels (κ_w = 0.902).

CONCLUSION

Weighted kappa adds confidence for clinical decision making by accounting for accuracy. Prenatal ultrasound is a reliable and accurate method of determining lesion level with near-perfect agreement to postnatal imaging within 2 spinal levels. Maternal BMI may not influence lesion level determination after initial diagnosis.

Determination of Anatomical Levels in Spina Bifida Fetuses with Ultrasound and MRI

PURPOSE

 The goal of this study was to assess the accuracy of prenatal anatomical level determination by ultrasound (US) and magnetic resonance imaging (MRI) by analyzing the congruence with the "true" anatomical level identified by postnatal MRI.

PATIENTS AND METHODS

 The first 60 patients undergoing fetal myelomeningocele surgery at The Zurich Center for Fetal Diangosis and Therapy were included in this study. Anatomical levels (i. e., first dysraphic vertebra) determined by prenatal US and MRI were compared to postnatal MRI. The level of agreement between the imaging modalities was evaluated with a Cohen's kappa test. Results > 0.6 were interpreted as good agreement, > 0.8 as excellent.

RESULTS

 The exact congruence between prenatal US and MRI compared to postnatal MRI was 33 % and 48 %, respectively, for an accuracy within one level difference of 80 % and 90 %, and within two levels difference of 95 % and 98 %, respectively. The level of agreement of prenatal US and MRI compared to postnatal MRI was 0.62 and 0.79, respectively. Most of the prenatally incorrectly assigned levels were assigned too high (worse) than the "true" level (US 88 % vs. MRI 65 %).

CONCLUSION

 Reliable exact prenatal level determination by US and MRI is not possible. However, the prenatal determination of the anatomical level of the lesion is good within one level margin of error. Prenatal US as well as MRI demonstrate a systematic error towards higher levels. The above considerations must be integrated into prenatal counselling.

Measurement of the Area and Circumference of the Leg: Preliminary Results of a New Method for Estimating Leg Muscle Trophism in Fetuses With Open Lumbosacral Spina Bifida

OBJECTIVE

To standardize a new technique to evaluate the fetal leg muscle trophism by measuring the area and circumference, and comparing this technique between normal and fetuses with open lumbosacral spina bifida (SB).

METHODS

Observational cross-sectional study was carried out on pregnant women with 26 weeks who were divided into two groups: Group I-fetuses with diagnosis of open lumbosacral SB; Group II-normal fetuses (control). In fetuses with SB, subjective evaluation of the lower limbs was performed (muscle echogenicity and leg movements). To estimate the leg muscle trophism, the measurement of the area and circumference of the leg were standardized, and the reproducibility of this method was performed.

RESULTS

Thirty-one fetuses with open lumbosacral SB and 51 normal fetuses were evaluated. The measurements of the area and circumference of the leg proved to be highly reproducible (intraclass correlation coefficient-ICC > 0.95). The leg area and circumference measurements were statistically lower in the SB group than in the control group (p < .001). When subjective ultrasound assessment demonstrated hypotrophy of the lower limbs, the measurements of the area and circumference of the leg were statistically lower when compared to normal fetuses (p < .001). Fetuses with open SB with abnormal lower limb movements had lower measurements of the area and circumference of the leg than fetuses with normal movements (p < .001).

CONCLUSION

A new technique for estimating fetal leg muscle trophism was standardized, which proved to be highly reproducible and was able to show the difference between normal and fetuses with SB.

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.

Is ventriculomegaly and hindbrain herniation seen before and after prenatal neural tube defect repair associated with a worse functional level than anatomical level at birth?

OBJECTIVE

To determine if the evaluation of the fetal ventricular system and hindbrain herniation (HBH) is associated with motor outcome at birth in prenatally repaired open neural tube defect (NTD).

METHODS

Retrospective cohort study of 47 patients with NTD who underwent prenatal repair (17 fetoscopic; 30 open-hysterotomy). At referral and 6 weeks postoperatively, the degree of HBH, ventricular atrial widths and ventricular volume were evaluated by MRI. Head circumference and ventricular atrial widths were measured on ultrasound at referral and during the last ultrasound before delivery. Anatomic level of the lesion (LL) was determined based on the upper bony spinal defect detected by ultrasound. We considered the functional level as worse than anatomical level at birth when the motor level was equal or worse than the anatomical LL.

RESULTS

26% (12/47) of the cases showed worse functional level than anatomical level at birth. Having a HBH below C1 at the time of referral was associated with a worse functional level than anatomical level at birth (OR = 9.7, CI95 [2.2-42.8], p < 0.01). None of the other brain parameters showed a significant association with motor outcomes at birth.

CONCLUSIONS

HBH below C1 before surgery was associated with a worse functional level than anatomical level at birth.

Myelomeningocele-Chiari II malformation-Neurological predictability based on fetal and postnatal magnetic resonance imaging

Objective

This systematic comparison between pre‐ and postnatal imaging findings and postnatal motor outcome assesses the reliability of MRI accuracy in the prognostication of the future long‐term (mean, 11.4 years) ambulatory status in a historic group of postnatally repaired myelomeningocele (MMC) cases.

Methods

A retrospective, single‐center study of 34 postnatally repaired MMC patients was performed. We used fetal and postnatal magnetic resonance imaging (MRI) to compare the fetal and postnatal radiological lesion level to each other and to the postnatal ambulatory level as a standard of reference and analyzed Chiari II malformation characteristics.

Results

In 13/15 (87%) and 29/31 (94%) cases, the functional level was equal to or better than the prenatal and postnatal radiological lesion level. A radiological lesion level agreement within two segments could be achieved in 13/15 (87%) patients. A worse than expected functional level occurred in cases with Myelocele (2/3 patients), coexistent crowding of the posterior fossa (2/3 patients) and/or abnormal white matter architecture, represented by callosal dysgenesis (1/3 patients). In all patients (2/2) with a radiological disagreement of more than two segments, segmentation disorders and scoliosis were observed.

Conclusion

Fetal and postnatal MRI are predictive of the long‐term ambulatory status in postnatally repaired MMC patients.

What's already known about this topic?

Fetal and postnatal magnetic resonance imaging (MRI) show a good correlation in identifying the level of the myelomeningocele (MMC) lesion.

Prenatal ultrasound (US) and fetal MRI show a comparable agreement, within two segments, in predicting the short‐term ambulatory status.

What does this study add?

Fetal and postnatal MRI have a good predictive value for the long‐term ambulatory status in patients with postnatal MMC closure.

MMC patients with worse than expected ambulatory status showed signs of vermian displacement and corpus callosum dysgenesis.

In MMC patients with spinal segmentation disorders and scoliosis, there was a major disagreement between fetal and postnatal MRI, specifically with regard to the MMC lesion level.

[Prenatal ultrasound prognostic of myelomeningocele at the era of fetal surgery]

Myelomeningocele (MMC) is a severe congenital condition responsible for motor and sensory impairments of the lower limbs, incontinence and cognitive impairment. Its screening, sometimes as early as the first trimester, is one of the major goals of modern prenatal care, supported by the emergence of prenatal surgery that results in a significant improvement in motor function, ambulation and ventriculoperitoneal shunt rate in patients undergoing in-utero surgery. From screening to pre- and post-operative prognostic evaluation, prenatal ultrasound is now an essential tool in the antenatal management of this condition. Using the multi planar and three-dimensional modes, it can be used to assess the vertebral level of MMC, which remains the key antenatal prognostic marker for motor function and ambulation, incontinence and the need for a ventriculo-peritoneal shunt. A careful and systematic ultrasound examination also makes it possible to assess the severity and progression of ventriculomegaly, to search for associated cerebral, spinal cord or vertebral anomalies, or to rule out exclusion criteria for in-utero surgery such as severe kyphosis or serious cortical anomalies. New tools from post-natal evaluation, such as the "metameric" ultrasound assessment of lower limb mobility, appear to be promising either for the initial examination or after in-utero surgery. Ultrasonography, associated with fetal MRI, cytogenetic and next generation sequencing, now allows a highly customized prognostic evaluation of these fetuses affected by MMC and provides the parents with the best possible information on the expected benefits and limitations of fetal surgery.

Prenatal predictors of motor function in children with open spina bifida: a retrospective cohort study

OBJECTIVE

To identify predictors for intact motor function (MF) at birth and at 12 months of life in babies with prenatally versus postnatally repaired open spina bifida (OSB).

DESIGN

Retrospective cohort study.

SETTING

Texas Children's Hospital, 2011-2018.

POPULATION

Patients who underwent either prenatal or postnatal OSB repair.

METHODS

Prenatal MF of the lower extremities was evaluated by ultrasound following a metameric distribution at the time of diagnosis (US1), 6 weeks postoperatively (or 6 weeks after initial evaluation in postnatally repaired cases) (US2) and at the last ultrasound before delivery (US3). At birth and at 12 months, MF was assessed clinically. Intact MF (S1) was defined as the observation of plantar flexion of the ankle. Results from logistic regression analysis are expressed as odds ratios (95% confidence intervals, P values).

RESULTS

A total of 127 patients were included: 93 with prenatal repair (51 fetoscopic; 42 open hysterotomy repair) and 34 with postnatal repair. In the prenatal repair group, predictors for intact MF at birth and at 12 months included: absence of clubfeet (OR 11.3, 95% CI 3.2-39.1, P < 0.01; OR 10.8 95% CI 2.4-47.6, P < 0.01); intact MF at US1 (OR 19.7, 95% CI 5.0-76.9, P < 0.01; OR 8.7, 95% CI 2.0-38.7, P < 0.01); intact MF at US2 (OR 22, 95% CI 6.5-74.2, P < 0.01; OR 13.5, 95% 3.0-61.4, P < 0.01); intact MF at US3 (OR 13.7, 95% CI 3.4-55.9, P < 0.01; OR 12.6, 95% CI 2.5-64.3, P < 0.01); and having a flat lesion (OR 11.2, 95% CI 2.4-51.1, P < 0.01; OR 4.1, 95% CI 1.1-16.5, P = 0.04). In the postnatal repair group, the only predictor of intact MF at 12 months was having intact MF at birth (OR 15.2, 95% CI 2.0-113.3, P = 0.03).

CONCLUSIONS

The detection of intact MF in utero from mid-gestation to delivery predicts intact MF at birth and at 12 months in babies who undergo prenatal OSB repair.

TWEETABLE ABSTRACT

Detection of intact motor function in utero predicts intact motor function at birth and at 1 year in fetuses who undergo prenatal OSB repair.

Relationships among classifications of impairment and measures of ambulatory function for children with spina bifida

Purpose: To examine associations between neurosegmental and functional level classifications in children with Spina Bifida, and determine which classification best reflects daily walking activity.Materials and methods: A prospective correlational study was conducted. Children with Spina Bifida were given ratings for lesion level [X-ray and International Myelodysplasia Study Group (IMSG) level determined by muscle strength] and functional level [Hoffer ambulatory level and Dias functional classification of myelomeningocele (FCM), Functional Mobility Scale (FMS)]. Daily walking activity was measured with a StepWatch monitor. Data were analyzed using Spearman rank correlation.Results: Sixty-one children were included, [56% male, average age 9.8 (SD 2.7) years]. The neurosegmental level classifications, X-ray lesion level and IMSG level showed little to no correlation with each other (r = 0.17). Among functional classifications, the Dias FCM correlated strongly with the FMS (r = 0.80-0.87). Correlations with steps per day were moderate to good for the Dias FCM and the FMS (r = 0.53-0.62), fair for IMSG level (r = 0.45), and little to none for X-ray lesion level (r = 0.03).Conclusions: The Dias FCM is comprehensive, including elements of neurosegmental level and function, and correlates well with walking activity. We recommend its use for classifying function in patients with Spina Bifida.Implications for rehabilitationFunctional classifications correlate better with daily walking activity than neurosegmental level classifications for patients with Spina Bifida.The Dias FCM includes neurosegmental and functional level elements, correlates well with daily activity, and is recommended for use in classifying Spina Bifida patients.Combined use of the FMS and activity monitoring is recommended for research and clinical assessment.

3T proton MR Spectroscopy evaluation of spinal cord lesions

Objective:

The objective of this study was to evaluate intramedullary spinal cord lesions using magnetic resonance spectroscopy and correlate the results with histo-pathological examination (HPE).

Materials and Methods:

Approval for this study was obtained from our institute ethical committee. Overall, 50 patients were recruited (29 male and 21 female), with a maximum age of 53 years and minimum age of 7 years. The mean age group of the study was 33 years. Standard magnetic resonance imaging (MRI) spine was done on a Siemens Skyra 3Tesla MRI scanner. MR Spectroscopy (MRS) was performed for all patients with intramedullary spinal lesions after getting written consent. It was performed using single-voxel method. The change in the metabolite peak was observed in each case and the results were compared with HPE. These collected data were analyzed using SPSS 16.0 version. Descriptive statistics, frequency analysis, and percentage analysis were used for categorical variables; and for continuous variables, mean and standard deviation were analyzed. McNemar's test was used to find the significance between conventional MRI MRS. In the above statistical tool, the probability value 0.05 is considered as significant level.

Results:

From our study, we observed that by applying routine MRI sequences alone, we could only detect around 58% of the cases correctly. However, when MRS was done along with the conventional MR imaging, the number of cases detected significantly increased to 84%. By applying McNemar's test and comparing the conventional MRI and MRS with HPE, it was found that statistically significant difference exists with P value of 0.007.

Conclusion:

MRS of the spinal cord is a promising tool for research and diagnosis because it can provide additional information complementary to other non-invasive imaging methods. It is an emerging tool and adds new biomarker information for characterization of spinal cord tumors, to differentiate benign from malignant lesions and to prevent unnecessary biopsies and surgeries.

Postfolate spina bifida lesion level change

BACKGROUND

Spina bifida accounts for a large proportion of birth defects in the United States. Studies have evaluated the decrease in prevalence at birth after folate fortification of food grains, but little is known about neurologic functional changes related to fortification. This study assesses the functional level of lesions in the prefortification and postfortification eras.

METHODS

Data were collected through retrospective review of medical records from a regional multispecialty clinic in Arizona. This study included individuals born between 1981-1995 (prefortification) and 1999-2013 (postfortification). Patients were included if they had a primary diagnosis of spina bifida with or without hydrocephalus.

RESULTS

There was a significant difference in functional lesion level with an 85% reduction in thoracic level lesions in the postfortification era (p < .005). There were no differences in gender or ethnicity across eras; however, Hispanic ethnicity had a higher number of cases overall (51.7%). The most common lesion level in both eras was mid-lumbar, accounting for 35.7 and 34.4% of cases in the prefolate and postfolate eras, respectively.

CONCLUSIONS

This study demonstrates a significant difference in the distribution of lesion level of spina bifida patients born in the postfortification era, based on neurologic function. Further research with a larger sample size is needed to determine if this observation holds true nationally.

Prenatal Assessment of the Position of Fetal Conus Medullaris as a Predictor of Fetal Spinal Lesions

OBJECTIVES

The aim of this study is to compare two different methods in assessment of the position of fetal conus medullaris (CM) and to explore the significance for assessment of CM.

METHODS

This study included both normal fetuses and those with the diagnosis of fetal spinal lesions. The position of fetal CM was performed sonographically using two methods: location of CM in relation to the vertebral body (CM level) and measurement of the conus sacrum (CS) distance.

RESULTS

The results showed that intra-observer and interobserver concordance was high for the two methods, both in the normal and abnormal groups. There was significant association between femur length and CS distance (R²  = 0.917) and between gestational age and CS distance (R²  = 0.892).

CONCLUSIONS

We propose the combined use of CM level location and CS distance measurement for the prenatal diagnosis of fetal spinal lesions for complementary needs.

Prenatal diagnosis of spina bifida: from intracranial translucency to intrauterine surgery

Accurate and timely prenatal diagnosis of spina bifida (SB) is a major goal of modern antenatal care. Prenatal screening for open SB should be first performed at the time of routine first-trimester ultrasound by examining the posterior fossa for obliteration or non-visualization of the fourth ventricle ("intracranial translucency") and cisterna magna. The second step of screening is the second-trimester anatomy scan, at which time the features of the Chiari type II malformation should be looked for, including ventriculomegaly, scalloping of the frontal bones ("lemon" sign), and backward and caudal displacement of the cerebellar vermis with obliteration of the cisterna magna ("banana" sign). In cases with positive findings, evaluation must include a focused examination of the spine for defects. In cases of closed SB and SB occulta, the cranial and posterior fossa features will not be present as they are not associated with leaking of spinal fluid and resultant hindbrain herniation, highlighting the fact that the spine should be examined thoroughly whenever possible during the second-trimester scan. In tertiary fetal medicine centers, two-dimensional and three-dimensional ultrasound allows an accurate determination of the location, type, extent, and upper level of the spinal defect as well as the presence of associated anomalies. Fetal magnetic resonance imaging should be restricted to candidates for intrauterine surgery as part of the preoperative protocol.

Prenatal ultrasound evaluation of segmental level of neurological lesion in fetuses with myelomeningocele: development of a new technique

OBJECTIVES

To report our preliminary experience in the use of prenatal ultrasound examination to assess lower-limb movements in fetuses with myelomeningocele. We aimed to determine the accuracy of this method to establish the segmental level of neurological lesion, as this is the best known predictor of the future ability to walk.

METHODS

This was a preliminary, observational study including fetuses with myelomeningocele operated on prenatally. The patterns of movements present and absent in the affected fetuses' lower limbs were evaluated systematically by ultrasound examination. According to the known nerve function associated with each muscle group, the segmental level of neurological lesion was established before birth. The agreement for the segmental levels assigned, between the prenatal ultrasound technique and the classical neurological clinical examination after birth (gold standard), was tested using the weighed kappa (wκ) index.

RESULTS

Seventy-one fetuses with myelomeningocele were evaluated at the Hospital Universitari Vall d'Hebron. After counseling, the parents opted for prenatal surgery (26 cases), termination of pregnancy (43 cases) or postnatal repair (two cases). Five patients did not fulfil the inclusion criteria for prenatal surgery and three were excluded after birth. In the 18 fetuses that underwent surgery and were analyzed, the agreement between prenatal and postnatal segmental levels assigned was 91.7% for the right limb (wκ = 0.80) and 88.9% for the left limb (wκ = 0.73).

CONCLUSIONS

The agreement found between prenatal and postnatal assignment of level of lesion in this preliminary study suggests that neurological sonographic evaluation is feasible before birth. This may provide accurate individualized information about the motor function and future ambulation prognosis of fetuses with myelomeningocele.

Intraoperative neurophysiological monitoring in patients undergoing tethered cord surgery after fetal myelomeningocele repair

OBJECT

Fetal myelomeningocele closure has been shown to be advantageous in a number of areas. In this study, the authors report on neural function in patients who had previously undergone fetal myelomeningocele repair and returned to the authors' institution for further surgery that included intraoperative neurophysiological monitoring.

METHODS

The authors retrospectively reviewed data obtained in 6 cases involving patients who underwent fetal myelomeningocele repair and later returned to their institution for spinal cord untethering. (In 4 of the 6 cases, the patients also underwent removal of a dermoid cyst [3 cases] or removal of an epidermoid cyst [1 case] during the untethering procedure.) Records and imaging studies were reviewed to identify the anatomical level of the myelomeningocele as well as the functional status of each patient. Stimulated electromyography (EMG) and transcranial motor evoked potential (tcMEP) recordings obtained during surgery were reviewed to assess the functional integrity of the nerve roots and spinal cord.

RESULTS

During reexploration, all patients had reproducible signals at or below their anatomical level on stimulated EMG and tcMEP recordings. Corresponding to these findings, prior to tethering, all patients had antigravity muscle function below their anatomical level.

CONCLUSIONS

All 6 patients had lower-extremity function and neurophysiological monitoring recording signals at or below their anatomical level. These cases provide direct evidence of spinal cord and nerve root conductivity and functionality below the anatomical level of the myelomeningocele, further supporting that neurological status improves with fetal repair.

(1)H-MR spectroscopy in the human spinal cord

SUMMARY

MR spectroscopy allows insight into the chemical composition of human tissue noninvasively. Thereby it can help to better characterize pathologic processes affecting the spinal cord and may provide important clinical markers for differential diagnosis. However, due to technical challenges, it has been rarely applied to the spinal cord. The aim of this review was to summarize the technical development and clinical studies using MR spectroscopy in the spinal cord. Main challenges of applying MR spectroscopy in the spinal cord are discussed, and a description of a state-of-the-art scan protocol is given. In conclusion, MR spectroscopy is a promising tool for research and diagnosis of the spinal cord because it can provide additional information complementary to other noninvasive imaging methods. However, the application of MR spectroscopy in the spinal cord is not straightforward, and great care is required to attain optimal spectral quality.

Comparison between 2D ultrasonography and magnetic resonance imaging for assessing brain and spine parameters in fetuses with spina bifida

PURPOSE

To compare two-dimensional ultrasonography (2DUS) and magnetic resonance imaging (MRI) for assessing brain and spine parameters in fetuses with spina bifida.

METHODS

A cross-sectional study was conducted on 15 fetuses with spina bifida (one with encephalocele, four with rachischisis and 10 with myelomeningocele). The size of the atrium of the lateral ventricle, percentage shortening of the cerebellum, degree of compromising of the first vertebra and total number of vertebras affected by herniation were assessed. The MRI examination was performed not more than 7 days after the 2DUS. To compare and correlate the parameters from the two techniques, the paired Student's t test and intraclass correlation coefficient (ICC) were used. To assess the correlations of atrium measurements from 2DUS and MRI with other parameters, Pearson's correlation coefficient (r) was used.

RESULTS

No significant difference was observed in any of the means of the parameters assessed using the two techniques (p > 0.05). Both 2DUS and MRI seemed to present satisfactory reliability in measurements on the size of the atrium of the lateral ventricle and the first vertebra affected (ICC = 0.88 and 0.75, respectively). Measurements on the atrium of the lateral ventricle from 2DUS correlated better with the other parameters than did measurements from MRI.

CONCLUSIONS

In fetuses with spina bifida, 2DUS and MRI present similar results, but measurements on the atrium of the lateral ventricle from 2DUS correlated better with the other parameters.

Prenatal neurologic anomalies: sonographic diagnosis and treatment

The low prevalence of fetal CNS anomalies results in a restricted level of exposure to, and limited experience for most obstetricians involved in, prenatal ultrasound. Sonographic guidelines for screening the fetal brain in a systematic way may increase the detection rate of fetal CNS anomalies, thus promoting correct referral to tertiary care centers offering patients a multidisciplinary approach to the condition. The aim of this review is to elaborate on the prenatal sonographic diagnosis and outcome of various CNS malformations. Detailed neurosonographic investigation has become available through high-resolution vaginal ultrasound probes and the development of a variety of 3-dimensional (3D) ultrasound modalities, such as ultrasound tomographic imaging. In addition, fetal magnetic resonance imaging is particularly helpful in the detection of gyration and neurulation anomalies, and disorders of the gray and white matter. Isolated mild ventriculomegaly is a rather common finding with good overall outcome. With an increasing diameter of the atria, however, and especially with the presence of associated malformations, long-term neurodevelopmental and behavioral outcome is disturbed in about 15% or more of cases. In view of recent developments in fetal therapy for neural tube defects, there is a clear need for a high level of ultrasound screening, work-up and counseling in tertiary care centers to identify those cases that might benefit from in utero intervention. The failure of prosencephalic midline induction and development results in midline defects ranging from alobar holoprosencephaly to isolated corpus callosum defects. The detection of callosal abnormaties is enhanced by 3D ultrasound, but counseling on neurodevelopmental outcome remains challenging. The Dandy-Walker spectrum includes isolated megacisterna magna, Blake's pouch cyst, hypoplasia of the vermis and Dandy-Walker malformation. Except for complete agenesis of the vermis associated with fourth ventricle cyst formation, data on long-term outcomes for the various conditions is largely lacking. Congenital cytomegalovirus (CMV) results in the highest incidence of children born with, or developing, long-term neurologic conditions. If proof of fetal infection has been delivered, microcephaly, cortical malformations, and intraparenchymal cysts show a strong correlation with poor outcome. Fetuses with CMV-related ultrasound abnormalities might benefit from maternal transplacental treatment. The aneurysm of the vein of Galen, a vascular malformation of the brain, often results in high cardiac output failure. After neonatal arterial embolization, survival is about 50% with normal neurologic development in 36% of cases. Over 50% of intracranial tumors are teratomata, presenting as fast-growing heterogeneous solid-cystic masses with calcifications. Most intracranial hemorrhages are related to the ventricular system, and prognosis is often poor, particularly in cases involving parenchymal and subdural bleeding. Proliferation disorders of the brain are often characterized by microcephaly. Their etiology is heterogeneous and prenatal diagnosis is often made late in gestation.

Prenatal evaluation of the position of the fetal conus medullaris

OBJECTIVES

To determine the position of the fetal conus medullaris during pregnancy in relation to the last vertebral body and to examine its use in detecting skin-covered spinal dysraphism.

METHODS

This was a retrospective study involving 300 consecutive ultrasound examinations between 15 weeks of gestation and term. Two operators independently assessed images of the spine to determine whether the conus medullaris and the last vertebral body could be visualized in a single image in a midsagittal plane. The distance between these two landmarks (the conus distance) was measured twice by both operators who were not aware of any previous measurements. Intra- and interobserver variability was assessed by 95% limits of agreement. Linear regression analysis was used to determine the relevant contributors to the conus distance and a normal range was computed based on the best-fit model. The normal results were compared with five cases of prenatally detected skin-covered spinal dysraphism.

RESULTS

In 84.7% of the 300 cases, both operators were able to visualize the conus medullaris and the last vertebral body. Ninety-five percent limits of agreement for the intraobserver variability in measurement of conus distance were ± 1.9 mm. For the interobserver variability, they were - 3.7 and 2.5 mm. We found a linear relationship between conus distance and gestational age, biparietal diameter and abdominal circumference. The strongest relationship was observed for femur length (conus distance = - 8.2 + femur length (mm)). In the five abnormal cases, conus distance was well below the 5(th) percentile.

CONCLUSIONS

Determination of conus distance allows for an objective and feasible assessment of the conus medullaris position. This parameter promises to be useful in the prenatal detection of skin-covered spinal dysraphism.

Role of prenatal ultrasound in predicting survival and mental and motor functioning in children with spina bifida

OBJECTIVE

To determine which prenatal ultrasound findings can predict survival and mental and motor functioning in children with spina bifida.

METHODS

Prenatal ultrasound examinations of all liveborn children who were prenatally diagnosed with spina bifida between 1997 and 2002 at the University Medical Centre, Utrecht (n = 41) were retrospectively reviewed for lesion level, head circumference, ventriculomegaly, scoliosis and talipes. These measures were correlated with postnatal anatomical (as assessed by magnetic resonance imaging (MRI)) and functional lesion levels, survival and motor and mental outcome at 5 years of age. The capacity of prenatal ultrasonography to determine lesion level was also assessed in all fetuses diagnosed with spina bifida from 2006-2007 (n = 18).

RESULTS

Nineteen infants died before the age of 5 years. Multivariate regression analysis showed that higher lesion level and head circumference > or = the 90th percentile on prenatal ultrasound examination were independent predictors of demise (P < 0.05 and P = 0.01, respectively). None of the ultrasound features was a predictor of motor or mental functioning. Ultrasound predicted anatomical lesion level within one level of the postnatal findings in 50% of the first cohort and 89% of the second cohort (P < 0.01). The level of the anatomical lesion as assessed by postnatal MRI differed from the functional lesion by as many as six vertebral levels.

CONCLUSIONS

Lesion level and head circumference on prenatal ultrasound are predictive of survival in children with spina bifida. No predictors were found for mental or motor function at the age of 5 years.

Prognosis for fetuses with antenatally detected myelomeningocele

The ultrasound diagnosis of myelomeningocele has been greatly improved by the recognition of associated abnormalities in the fetal skull and brain, potentially leading to an increased number of cases detected during pregnancy. Unfortunately, the counselling of potential parents about the natural history and prognosis of myelomeningocele is frequently based on extrapolations from data in which the diagnosis was made following delivery. Moreover, much of this information predates recent advances in paediatric care. In 1981, Leonard stated “as most children (with myelomeningocele) will grow to be productive, participating adults, then perhaps we should consider myelomeningocele a new disease”1. It is, therefore, appropriate to review recent outcome data for children with myelomeningocele, emphasising those studies where the diagnosis was made before delivery. This review will concentrate on issues of particular concern to the perinatal obstetrician, such as the reliability of sonographic diagnosis, the frequency of karyotypic anomalies, the likely longterm infant outcome and the most appropriate mode of delivery.

The dysraphic levels of skin and vertebrae are different in mouse fetuses and neonates with myelomeningocele

BACKGROUND

Mouse fetuses with spontaneous myelomeningocele (MMC) were investigated, determining the various levels of dysraphism in soft tissue, spinal cord, and vertebrae. Morphology was correlated with hind limb function.

METHODS

Viable curly tail/loop tail mouse fetuses underwent qualitative standardized ex utero examination of tail and hind limb sensitivity and motor response. Afterward, they were processed either for histology or skeletal preparation.

RESULTS

All animals displayed identical cranial levels of soft tissue and neural defects. The cranial opening of the vertebral defects were invariably located more cranially (range, 0.5-5 vertebrae; mean = 2.25). The caudal opening of soft/neural tissue and bony defects was invariably at the coccygeal base. The comparison of functional with morphological levels demonstrated that, in 52.5%, the level of the soft/neural tissue dysraphism and, in 47.5%, the level of the bony opening correlated with the neurologic deficit.

CONCLUSION

The naturally occurring soft tissue coverage over the MMC could exert a protective effect toward the underlying spinal cord. This interpretation supports the concept that in utero acquired destruction of exposed neural tissue is a main factor for the neonatal functional deficit. Thus, these data are consistent with the rationale for prenatal MMC repair in humans.

In utero Repair of Myelomeningocele: Rationale, Initial Clinical Experience and a Randomized Controlled Prospective Clinical Trial

Myelomeningocele (MMC), one of the most common congenital malformations, can result in severe lifelong disabilities, including paraplegia, hydrocephalus, Arnold-Chiari II malformation, incontinence, sexual dysfunction, skeletal deformations, and mental impairment. MMC was the first nonlethal anomaly to be treated by fetal surgery. Studies in animals provide compelling evidence that the primary cause of the neurological deficit associated with MMC is not simply incomplete neurulation but rather chronic mechanical injury and amniotic-fluid-induced chemical trauma that progressively damage the exposed neural tissue during gestation. Initial results suggest that the surgical repair of MMC before 25 weeks of gestation may preserve neurological function, reverse the hindbrain herniation of the Arnold-Chiari II malformation, and obviate the need for postnatal placement of a ventriculoperitoneal shunt. As it is currently unknown whether fetal surgery for MMC is truly beneficial compared to standard postnatal care, a randomized, controlled clinical trial has been initiated within the United States.

Are myelodysplastic children receiving sufficient health care in Turkey? An analysis of the problems in primary management and their impact on neuro-urological outcome

OBJECTIVE

To investigate the problems in the primary care of children with spina bifida and to analyze their impact on neuro-urological outcome in Turkey. Information from mothers about the disease, difficulties in getting medical services, availability and efficacy of prenatal ultrasound, and folic acid intake was also assessed.

PATIENTS

A retrospective review of 476 children registered in the pediatric urology section of our institutional multidisciplinary spina bifida clinic between 1996 and 2005 was made. All children were assessed for the time of primary repair, time to first neuro-urological visit, and compliance to follow up. A phone interview was made with 166 mothers to obtain data regarding their educational status, supplementary folic acid intake before/during gestation, compliance to obstetric follow up, prenatal diagnosis and counseling, information about the importance of neuro-urological surveillance, and difficulties in neuro-urological follow up.

RESULTS

Two-thirds of the mothers had an educational status of elementary school or lower. Phone interviews revealed inadequate obstetric follow up in 42% and a low prenatal diagnosis rate (49%) in those under regular follow up. Chart review revealed a significant delay in timing of primary surgical closure (mean 3 months and 2.9 years for open and closed lesions, respectively) and first neuro-urological follow-up visit (mean 1.8 years and 9.7 months after primary repair for open and occult lesions, respectively). Reasons for delayed closure were misguided advice of the nurse/midwife involved in delivery and inability to obtain tertiary health care. Socioeconomic inadequacy of the families and inefficacy of the health insurance system were the most important factors impairing follow up.

CONCLUSIONS

Serious problems exist in the prevention, prenatal diagnosis and primary management of children with myelodysplasia in Turkey. As a consequence, neuro-urological follow up starts relatively late, which adversely affects the urological prognosis.

Antenatal ultrasound and magnetic resonance imaging in localizing the level of lesion in spina bifida and correlation with postnatal outcome

OBJECTIVE

To compare prenatal ultrasonography and magnetic resonance imaging (MRI) in the diagnosis of spina bifida with postnatal MRI/surgical findings and to study the postnatal outcome in relation to the level of lesion and head signs on antenatal imaging.

METHODS

A retrospective study of babies referred to a tertiary neurosurgical unit with a diagnosis of spina bifida in the years 2000-2002 was performed. The levels of lesions and head signs diagnosed using antenatal ultrasonography and MRI were compared with postnatal MRI and operative findings. The levels of lesions and head signs diagnosed pre- and postnatally were used to study the correlation with neurological outcome at a mean follow-up period of 12 months.

RESULTS

Twelve antenatally diagnosed and five postnatally diagnosed cases of spina bifida were seen. The level of lesion as identified by antenatal ultrasound correlated with that observed postnatally in 8/12 cases and the antenatal ultrasound diagnosis of ventriculomegaly was confirmed postnatally in all cases. The level of lesion as identified by antenatal MRI correlated with that observed postnatally in 4/8 cases (50%) and the antenatal MRI diagnosis of ventriculomegaly was confirmed postnatally in 5/8 (63%) cases. 12/17 babies were found to have residuals in the immediate postnatal urodynamic studies, of which 83% (n = 10) required intermittent catheterization of the bladder at 12 months of age. Low spinal lesions were associated with increased bladder morbidity when compared to high spinal lesions (8/10 vs. 4/7, P < 0.05) (odds ratio (OR) = 10.0; 95% CI, 1.05-95.01). The level of spinal lesion and the presence of ventriculomegaly did not have any statistically significant correlation with motor functions, morbidity and developmental milestones.

CONCLUSIONS

Antenatal ultrasonography is a good tool in the diagnosis of spina bifida. We could not demonstrate any advantage of antenatal MRI over ultrasonography. There is better correlation of ultrasonography than MRI with postnatal MRI/operative findings in terms of level of lesion and head signs. Low spinal lesions appear to be associated with increased bladder morbidity.

Prenatal assignation of lesion levels in neural tube defects by using ultrasonography. Case report and review of the literature

Myelomeningoceles are routinely diagnosed prenatally by using ultrasonography. Because the level of the neural defect has been shown to correlate with functional and cognitive outcome in infants with myelomeningocele, it is of prognostic importance to identify the level prenatally. The authors report on a case in which the postnatal vertebral level of the myelomeningocele was more rostral than expected based on prenatal imaging.

Myelomeningocele: prenatal evaluation--comparison between transabdominal US and MR imaging

PURPOSE

To compare transabdominal ultrasonography (US) with fetal magnetic resonance (MR) imaging in the prenatal evaluation of myelomeningocele lesion level.

MATERIALS AND METHODS

Prenatal US images, pre- and postnatal MR images, and postnatal spinal radiographs obtained in the first 100 fetuses who underwent intrauterine myelomeningocele repair were the basis for this study. Each image was used to assign a lesion level. The assigned levels were compared by means of the kappa statistic, as an index of agreement.

RESULTS

All fetuses underwent prenatal US. Sixty-one fetuses underwent prenatal MR imaging. Fifty fetuses underwent both postnatal spinal radiography and postnatal MR imaging, and an additional 34 fetuses underwent one postnatal study but not the other. When findings on prenatal US images were compared with those on postnatal radiographs, the findings agreed within one spinal level in 79% (55 of 70, kappa = 0.60) of cases. When findings on prenatal MR images were compared with those on postnatal radiographs, the findings agreed in 82% (31 of 38, kappa = 0.63) of cases. Findings on postnatal MR images and those on postnatal spinal radiographs agreed within one spinal level in 100% (50 of 50, kappa = 1.0) of cases.

CONCLUSION

Findings at prenatal MR imaging and prenatal US are equally accurate for the assignment of a lesion level in a fetus with myelomeningocele. Given that findings with both modalities will lead to misdiagnosis of the spinal level by two or more segments in at least 20% of cases, care should be exercised when neurologic outcome is predicted on the basis of these studies alone.

Association between prenatal sonographic findings and post-natal outcomes in 30 cases of isolated spina bifida aperta

This study presents 30 cases of fetal isolated spina bifida aperta (SBA) to identify prenatal ultrasound findings that could predict the prognosis. Comparisons between surviving patients who had normal (group 1) and abnormal (group 2) post-natal neurological outcomes were made for three different prenatal signs, that is, site of vertebral lesion, presence and degree of ventriculomegaly and presence of talipes. The site of the lesion was the most significant outcome predictor, as high spinal dysraphisms were observed in 2 patients (2/7-28.6%) in group 1 and in 15 patients (15/19-79.0%) in group 2 (p = 0.03). The presence of fetal ventriculomegaly was associated with impaired post-natal neurological development, as it occurred in 4 patients (4/7-57.1%) in group 1 and in 18 patients (18/19-94.7%) in group 2 (p = 0.04). The presence of talipes did not significantly differ between the two groups. Patients with abnormal intellectual outcome (8/26-30.8%) had significantly greater (p = 0.018) lateral ventricle/hemisphere ratios (mean = 0.74, standard deviation = 0.13) than those with normal intellectual development (mean = 0.54, standard deviation = 0.18). Mean post-natal follow-up was at 23 months (standard deviation = 15 months).

A diagnostic approach for the evaluation of spina bifida by three-dimensional ultrasonography

OBJECTIVE

To describe a prenatal diagnostic method for evaluating spina bifida by three-dimensional ultrasonography.

METHODS

Two- and three-dimensional ultrasonography were used to determine the extent of vertebral defects among fetuses with spina bifida. Spinal levels were independently counted from the most caudal thoracic vertebra with a rib (e.g., 12th thoracic rib). A virtual cutting plane was manipulated through a volume-rendered spine to generate optimal multiplanar views for this blinded analysis. Prenatal diagnosis was compared with a postnatal analysis of bony spine defects derived from radiographic films or magnetic resonance imaging.

RESULTS

Nine fetuses were examined by two-dimensional ultrasonography (21.8 +/- 3.4 menstrual weeks) and three-dimensional ultrasonography (22.8 +/- 4.4 menstrual weeks). For two-dimensional ultrasonography, the spinal level agreed to within 1 vertebral segment in 6 of 9 infants. In contrast, three-dimensional ultrasonography agreed to within 1 vertebral segment in 8 of 9 infants. Three fetuses had vertebral defect levels on two-dimensional ultrasonography that were 1.5 to 2 segments away from postnatal findings. The same fetuses had results that were within 1 vertebral segment on three-dimensional ultrasonography. Volume rendering showed splayed vertebral pedicles and disrupted vertebrae. An intact meningeal sac was easily rendered in 5 of 9 subjects.

CONCLUSIONS

Multiplanar views are generally more informative than rendered views for localizing bony defects of the fetal spine. The level of the defect on three-dimensional ultrasonography correlates well with those on two-dimensional ultrasonography and postnatal imaging studies. This approach may improve characterization of spina bifida by adding diagnostic information that is complementary to the initial assessment by two-dimensional ultrasonography.

A new look at myelomeningoceles: functional level, vertebral level, shunting, and the implications for fetal intervention

OBJECTIVE

Previous reports have suggested that 80% to 85% of patients who have a myelomeningocele (MMC) and undergo surgical repair after birth develop hydrocephalus and require the placement of a ventricular shunt. However, the rate of shunting as a function of spinal level is not well established. We sought to determine the distribution of postnatally repaired MMC lesions as characterized by both functional and radiologic assessment, as well as the incidence of shunting when patients were categorized according to these 2 methods.

METHODS

A retrospective chart review of 297 patients who were born with open MMCs and followed in the spina bifida clinic at the Children's Hospital of Philadelphia was performed. The presence or absence of a shunt was determined for each patient. Functional spinal level was determined by the best-recorded neurologic examination and vertebral level by spine radiographs.

RESULTS

The overall rate of ventricular shunting was 81%. The level of the lesion significantly affected the incidence of shunting, with more cephalad lesions correlating with higher rates. This was true both for functional and radiologic categorizations. A significantly higher shunt rate was found among patients with sacral lesions when categorized by radiologic rather than functional criteria. In 86% of patients, the functional level was found to be equal to or higher (worse) than the radiologic level.

CONCLUSIONS

This study describes the natural history of ventricular shunting in MMC patients with relation to both radiologic and functional criteria. Fetal MMC closure is being performed in some centers in an attempt to decrease the incidence of shunting and to improve leg function in selected patients. The present data may serve as a comparison group and aid in the design and analysis of a prospective trial to assess the efficacy of this new procedure.

Can prenatal ultrasound findings predict ambulatory status in fetuses with open spina bifida?

OBJECTIVE

To determine whether prenatal sonographic findings in fetuses with open spina bifida can predict ambulatory potential and the need for postnatal shunt placement.

STUDY DESIGN

Ongoing pregnancies complicated by isolated open spina bifida from January 1996 to March 2000 were studied retrospectively. Static images and reports generated every 3-4 weeks from diagnosis until delivery were reviewed for lesion level and type, ventricular width, and lower extremity appearance. Operative summaries as well as neonatal and pediatric charts were reviewed. Ambulatory was defined in infants > or =2 years old as walking with or without appliances. In those <2 years of age, ambulatory was defined as at least 4/5 lower extremity muscle strength.

RESULTS

Thirty-three cases of isolated open spina bifida were identified. Lower (more caudal) lesion levels and smaller ventricular size were associated with ambulatory status in univariate analyses (P <.001, P =.003, respectively). No infant with a thoracic lesion was ambulatory (n = 11); all had ventriculomegaly diagnosed prenatally and all required shunt placement. In contrast, all infants with L4-sacral lesions (n = 10) were ambulatory, and 60% had ventriculomegaly diagnosed prenatally. Of patients with L1-L3 lesions (n = 12), 50% were ambulatory. In this group, ambulatory potential could not be determined by the presence of ventriculomegaly, ventricular size, or the presence of club foot. In the entire cohort, no infant with a myeloschisis was ambulatory, and all infants except one with a sacral lesion required postnatal shunt placement.

CONCLUSIONS

Sonographic determination of lesion level and type is useful in predicting the ambulatory potential of fetuses with open spina bifida.

Developmental outcomes of children with myelomeningocele: prenatal predictors

OBJECTIVE

The purpose of the current investigation was to determine cognitive developmental outcomes for a cohort of children with prenatally detected myelomeningocele and to determine whether the variables of (1) severity of ventriculomegaly and (2) anatomic level of lesion were predictive of cognitive development.

STUDY DESIGN

Prenatal ultrasonographic examinations were reviewed by a single perinatologist to determine the degree of ventriculomegaly and the anatomic level of the lesion. Ventriculomegaly was defined as a lateral ventricular atrial width > 10 mm. Anatomic level of lesion was defined as (1) thoracic, (2) high lumbar, (3) midlumbar, (4) low lumbar-high sacral, or (5) sacral. Cognitive developmental quotients for surviving children were determined by one of two developmental pediatricians with use of a modified version of the Clinical Adaptive Test/Clinical Linguistic Auditory Milestone Scale, a measure of visual-motor and language abilities.

RESULTS

The mean cognitive developmental quotient for subjects with absent to mild ventriculomegaly was 90.3 (range 54 to 120, SD 17.4), whereas the mean cognitive developmental quotient for those with moderate to severe ventriculomegaly was 74.0 (range 65 to 100, SD 17.1) (p < 0.01). There was a negative correlation between the degree of ventriculomegaly and the cognitive developmental quotient (r = -0.43, p < 0.025) and a positive correlation between the level of the lesion and the cognitive developmental quotient (r = 0.50, p < 0.01).

CONCLUSIONS

The degree of ventriculomegaly determined on high-resolution prenatal ultrasonography is predictive of early cognitive development in children with myelomeningocele, with worsening ventriculomegaly being associated with lower cognitive developmental quotients. The anatomic level of the lesion also has predictive value, with lower level lesions being associated with more favorable cognitive outcomes. However, because of the high degree of variance in developmental quotients within the two ventriculomegaly groups, we advise clinicians to use caution in the interpretation and use of our data.

Functional motor outcome in children with myelomeningocele: correlation with anatomic level on prenatal ultrasound

Fifteen children with prenatally diagnosed myelomeningocele were followed for at least three years to determine the relations between prenatal anatomic level visualized on high-resolution ultrasound, radiographic level, neuromotor level and functional motor outcome. Prenatal anatomic level accurately predicted neuromotor level and functional motor outcome in 12 of the children and was a better predictor than motor level at birth. Clinicians involved in prenatal counseling may use the anatomic level determined on high-resolution ultrasound to discuss motor prognosis with families.