US of the spinal cord in newborns: spectrum of normal findings, variants, congenital anomalies, and acquired diseases

International Consensus Statement on the Radiological Evaluation of Dysraphic Malformations of the Spine and Spinal Cord

Dysraphic malformations of the spine and spinal cord (DMSSC) represent a spectrum of common congenital anomalies typically (though not exclusively) affecting the lower spinal segments. These may be responsible for varying degrees of neurologic, orthopedic, and urologic morbidity. With advances in neuroimaging, it is now possible to better diagnose and evaluate these disorders both prenatally and postnatally. Neuroimaging, performed at the right time and with technique optimization, is integral in guiding clinical management. However, the terminology used to describe these lesions has become increasingly confusing, and there is a lack of consensus regarding the essential radiologic features and their clinical weighting. This variability in radiologic practice risks unstructured decision making and increases the likelihood of suboptimal, less informed clinical management. In this manuscript, the first of a series of consensus statements, we outline a standardized international consensus statement for the radiologic evaluation of children with suspected DMSSC derived from a critical review of the literature, and the collective clinical experience of a multinational group of experts. We provide recommendations for plain radiography, sonography, CT, and MR imaging in the evaluation of DMSSC with an emphasis on technique of imaging and imaging protocols.

Developmental Abnormalities of the Pediatric Spine: A Review of the Correlation Between Ultrasound and MRI Findings

A broad spectrum of spinal pathologies can affect the pediatric population. Ultrasound (US) is the primary modality for pediatric spine assessment due to its widespread availability, non-requirement of sedation, and absence of ionizing radiation. Supplementing this, MRI offers an in-depth exploration of these conditions, aiding in preoperative strategizing. In this review, we examine the clinical indications, methodologies, and protocols for US and MRI scans of the pediatric spine. Additionally, we illustrate normal pediatric spinal anatomy, highlighting several examples of normal variants that are often misinterpreted. Through a series of case-based illustrations, we offer a comprehensive overview of various pathological conditions such as tethered cord, spinal dysraphism, spinal lipoma, diastematomyelia, and dermal sinus tract, among others. Furthermore, we explore the correlation between US and MRI findings for these lesions, employing real-world cases to enhance our understanding of this topic.

Do we know the normal anterior-posterior diameters of the spinal cord and canal in newborns?

Aim: We aim to reveal the normal anterior-posterior diameter of the spinal cord and canal at cervical, thoracic and lumbar levels in newborn with sonographic measurements and to create a reference value. Also, we aim to reveal whether the anterior-posterior diameter at these levels will vary with the newborn's head circumference, gender, height and weight. Thus, we aim to be one of the pioneering studies in the literature Material and Method: Statistical analysis was performed to determine normal anterior-posterior diameter for the spinal canal and spinal cord at each vertebral level, and their correlations with birth weight, length and head circumference. Results: 188 newborns were included. The mean anteroposterior spinal canal diameter in male newborns was significantly higher compared to females (9.27±0.83 vs 9.00±0.79, p=.020). There was a positive correlation between spinal cord anterior-posterior diameter and head circumference at thoracic level, which was statistically significant. There was a positive correlation between spinal canal diameter and height at thoracic level. There was a positive correlation between spinal canal diameter and weight at lumbar level. Conclusion: The establishment of the normal values for anterior-posterior diameters of the spinal cord in healthy newborns may contribute the current literature data.

“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.

Anatomy of the Ventricles, Subarachnoid Spaces, and Meninges

The ventricular system, subarachnoid spaces, and meninges are structures that lend structure, support, and protection to the brain and spinal cord. This article provides a detailed look at the anatomy of the intracranial portions of these structures with a particular focus on neuroimaging methods.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part II: Joint Pathologies, Pediatric Applications, and Guided Procedures

The second part of the Guidelines and Recommendations for Musculoskeletal Ultrasound (MSUS), produced under the auspices of EFSUMB, following the same methodology as for Part 1, provides information and recommendations on the use of this imaging modality for joint pathology, pediatric applications, and musculoskeletal ultrasound-guided procedures. Clinical application, practical points, limitations, and artifacts are described and discussed for every joint or procedure. The document is intended to guide clinical users in their daily practice.

Spontaneous Disappearance of Filar Cysts Diagnosed by Transabdominal Ultrasonography: A Report of Three Cases

Filar cysts (FCs) can be detected using ultrasound before or after delivery. They usually present as anechoic structures with a clear boundary just caudal to the lower end of the conus medullaris. They are generally considered a physiological variation and do not affect health. Some studies have pointed out that FCs in children can disappear spontaneously, as identified by ultrasound or magnetic resonance imaging. Three cases of FCs diagnosed by prenatal transabdominal ultrasound were reported in this study, and it was observed that FCs could disappear spontaneously in utero. The shortest time of disappearance was 4 weeks.

SPINAL DERMAL SINUS COMPLICATION IN CHILDREN: CASE SERIES AND LITERATURE REVIEW

ABSTRACT Introduction: Dermal sinus (DS) is a rare dysraphism. It can be asymptomatic, become infected, and produce severe neurological symptoms. Our objective is to present a series of pediatric cases with spinal DS complicated byinfections (DSCI), describe the findings correlated with the anatomy in a stillbirth, as well as the associated pathologies and their treatment. Method: We analyzeddifferent variables in the clinical histories of 5 children with spinal DSCI. In addition, an anatomical dissection of a stillbirth with lumbar DS was performed. Results: Two males and 3 femaleswith DSCI and a mean age of 2 years and 9 months were included: 2 lumbar (one in the midline and the other in theparamedian region), 1 in the thoracic region, 1 in the upper cervical region,and 1 in the lumbosacral region. The forms of presentation were 3 meningeal profiles (one with pain andlocalized swelling) and 3 neurological deficits (one associated with the meningeal profile and another associated with pain and a tumor). In all cases, the tract of the DS was identified by magnetic resonance imaging (MRI).Associated lesions included 1 dorsal intramedullary dermoid cyst, 1 tethered lumbar spinal cord with syringomyelia, 1 partial cervical medullary disconnection, and 2 spinal dysraphisms. Four were operated on and one died of infectious complications before surgery. In the 12-week-old male fetus with lumbar DS, a permeable tract to the subarachnoid space was verified. Conclusions: DSCIsshould bestudied with MRI to identify their tracts, infectious complications of thecentral nervous system, associated malformations, inclusion tumors, and to enabledifferential diagnosis. Once diagnosed, they should be urgently treated both surgically and with prolonged antibiotictherapy. Level of Evidence IV; Therapeutic Study (Treatment Outcome Investigation)

Ultrasound of congenital spine anomalies

Ultrasonography (US) is the first-line imaging modality for screening neonates and young infants with suspected spinal abnormalities. Whether performed for a suspicious congenital skin lesion, such as a lumbosacral tract or lipomatous mass, or abnormal neurological findings, US can help define spinal anatomy, characterize congenital spine malformations, and direct further work-up and management. The purpose of this article is to review the diagnostic imaging approach to infant spine US, including technique and indications, normal anatomy and variants with a focus on embryological origins, and classification and diagnosis of congenital spine malformations.

Predisposing conditions for bacterial meningitis in children: what radiologists need to know

A variety of underlying diseases can predispose infants and children to bacterial meningitis (BM). For the diagnosis, treatment, and prevention of its recurrence, radiologists should be familiar with its predisposing conditions so that they can suggest the appropriate imaging approach. Predisposing conditions of BM can be broadly classified into two categories: infection spread from the adjacent tissue to the cerebrospinal fluid (CSF) space and immunodeficiency. Diseases in the former category are further divided according to regardless of whether there is a structural defect between the CSF space and the adjacent tissue. When a structural defect is suspected in a patient with BM, computed tomography (CT) of the head and magnetic resonance (MR) imaging are first-line imaging examinations. Radionuclide cisternography should be implemented as a second-line step to identify the CSF leak site. In patients with suspected parameningeal infection without any structural defect, such as sinusitis or otitis media/mastoiditis, CT or MR images can identify not only the disease itself but also the associated intracranial complications. The purpose of this article is to discuss the diagnostic approach and imaging findings associated with the variety of conditions predisposing patients to recurrent BM, focusing on the role of radiology in their management.

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.

Normal anterior-posterior diameters of the spinal cord and spinal canal in healthy term newborns on sonography

BACKGROUND

There are no published normal values for spinal cord and canal diameters in newborns. Spinal cord and spinal canal diameters are assessed subjectively by radiologists without any objective values for the upper limit of normal.

OBJECTIVE

To determine normal values for anteroposterior (AP) diameters of the spinal cord and spinal canal on sonography in healthy term newborns.

MATERIALS AND METHODS

We performed ultrasound of the entire spine on 37 healthy newborns (23 male, 14 female). The AP diameters of the spinal canal and spinal cord were measured at representative levels of the cervical (C4, C5, C6), thoracic (T5, T6, T7, T8) and lumbar spine (lumbar enlargement and above and below the lumbar enlargement level). Statistical analysis was performed to determine the mean and standard deviation of the spinal canal and spinal cord AP diameter at each aforementioned vertebral level, and their correlations with birth weight, length and head circumference.

RESULTS

The mean AP spinal cord diameter was 4.1±0.5 mm at the cervical level, 3.3±0.3 mm at the thoracic level and 4.4±0.6 mm at the lumbar level. The mean AP spinal canal diameter was 7.7±0.7 mm at the cervical level, 6.2±0.8 mm at the thoracic level, and 8.4±0.7 mm at the lumbar level.

CONCLUSION

In this prospective study, we have determined normal values for AP diameters of the spinal cord and spinal canal on sonography in healthy newborns at representative cervical, thoracic and lumbar levels. This data may assist in evaluating the neonatal spine in clinical situations such as suspected spinal cord injury.

MRI imaging findings in prune perineum syndrome: an extremely rare entity

We report a case of prune perineum syndrome, an extremely rare entity with only four cases reported to date, describing some typical clinical and radiologic features. We also present a newly associated imaging finding, the terminal ventricle’s cystic dilatation, and briefly discuss the differential diagnosis.

Bedside Ultrasound for the Evaluation of Epidural Hematoma After Infant Lumbar Puncture

BACKGROUND

Unsuccessful lumbar puncture (LP) attempts may lead to epidural hematoma (EH) formation within the spinal canal at the site of needle insertion, which can affect subsequent attempts. We aimed to determine the rate of EH formation after infant LP using bedside ultrasound (US). Furthermore, we aimed to correlate both perceived trauma during LP and cerebral spinal fluid (CSF) red blood cell (RBC) counts with EH formation.

METHODS

We enrolled infants younger than 6 months who underwent LP in the emergency department. The primary investigator performed a bedside US of the lumbar spine, which was reviewed and interpreted by a pediatric radiologist. Treating clinicians performed the procedure and were asked to classify each attempt as "traumatic" or "atraumatic." Cerebral spinal fluid RBC counts were recorded.

RESULTS

Thirty-one percent of patients had evidence of post-LP EH, 17% of which completely effaced the thecal sac. Forty percent of patients with at least 1 traumatic attempt had evidence of EH, whereas 25% without reported trauma showed EH (P = 0.17). Patients with EH had a median CSF RBC cell count of 186 cells/mm (range, 0-239,525) compared with 5 cells/mm (range, 0-3429) in patients without evidence of EH (P = 0.008).

CONCLUSIONS

Epidural hematomas are frequent after LP. Perceived trauma during LP and CSF RBC counts are not adequate predictors of EH formation. Point-of-care US may be a valuable adjunct to help guide subsequent needle insertions sites for repeat attempts after an unsuccessful LP.

Effects of awake caudal anesthesia on mean arterial blood pressure in very low birthweight infants

Background

Intraoperative blood pressure is a relevant variable for postoperative outcome in infants undergoing surgical procedures. It is therefore important to know whether the type of anesthesia has an impact on intraoperative blood pressure management in very low birth weight infants. Here, we retrospectively analyzed intraoperative blood pressure in very low birthweight infants receiving either awake caudal anesthesia without sedation, or caudal block in combination with general anesthesia, both for open inguinal hernia repair.

Methods

Ethical approval was provided by the University of Tuebingen Ethical Committee on 05/29/2018 with the project number 403/2018BO2. Patient records of infants admitted by the neonatologist (median age at birth 31.1 ± 3.5 weeks, median weight at birth 1240 ± 521 g) which were scheduled for inguinal hernia repair were retrospectively evaluated for the course of mean arterial blood pressure and perioperative interventions to stabilize blood pressure. A total of 42 patients were included, 16 patients (11 boys, 5 girls) received awake caudal anesthesia, 26 patients (22 boys, 4 girls) a combination of general anesthesia and caudal block.

Results

Approximately 3% of the measured mean arterial blood pressure values in the caudal anesthesia group were below a critical margin of 35 mmHg, in contrast to 47% in the combined anesthesia group (p < 0.001). Patients in the latter group showed a significantly larger drop of mean arterial blood pressure below 35 mmHg (4.7 ± 2.7 mmHg vs. 1.9 ± 1.6 mmHg; p < 0.005) and a significantly longer time of mean arterial blood pressure below 35 mmHg (25.6 ± 26.0 min vs. 0.9 ± 2.3 min; p < 0.001), although they received more volume and vasopressor boluses for stabilization (27 ± 14.8 ml vs. 10 ± 4.1 ml; p < 0.01 and 0.15 ± 0.06 ml vs. 0 ml of cafedrine/theoadrenaline; p < 0.001).

Conclusions

The study indicates that the use of caudal block as stand alone procedure for inguinal hernia repair in very low birthweight infants might be advantageous in preventing critical blood pressure drops compared to a combination of caudal block with general anesthesia.

Filum terminale lipoma revealed by screening spinal ultrasonography in infants with simple sacral dimple

PURPOSE

Spine ultrasound (US) examinations are widely performed in neonates and infants with sacral dimple to exclude associated congenital malformations. Increased utilization of, and improvements in, sonographic technology has resulted in the frequent identification of echogenic filum terminale (FT) containing fat below the conus medullaris, termed FT lipoma or fatty FT. We examined the value of screening US, especially for diagnosis of FT lipoma, in infants with "simple sacral dimple."

METHODS

This study was a retrospective review of spinal US and magnetic resonance imaging (MRI) findings performed in our hospital on full-term and preterm infants with simple sacral dimple. We reviewed the clinical records and spinal sonographic scans of 337 patients, and the MRI scans of 40 patients with simple sacral dimple. We evaluated the thickness and echogenicity of FT on US, and the presence of fat in the FT was determined by MRI.

RESULTS

In total, 50 of the 337 patients showed strong echogenic FT on US. Correlation with MRI data was possible in 40 of the 50 patients with strong echogenic FT. MRI scans of all 40 of these patients revealed the presence of fat in the FT. The maximum thickness in the strong echogenic area of the FT lipomas of these 40 patients was 1.7 ± 0.4 mm (range 1.2-2.5 mm), and the minimum thickness was 1.1 ± 0.2 mm (range 0.8-1.4 mm). Among the 40 infants, 13 (32%) had maximum FT thickness > 2 mm (mean thickness 2.2 ± 0.2 mm; range 2-2.5 mm) and 27 (68%) had echogenic FT < 2 mm thick (mean thickness 1.5 ± 0.2 mm; range 1-1.9 mm). The length of the echogenic segment on US was about 1.9-5.1 cm (mean length 3.4 ± 1.1 cm). All 40 patients showed FT lipoma without any associated abnormalities, such as cord tethering or low-lying conus. Among the total population of 337 patients, 30 (8.9%) showed borderline low-lying conus medullaris located at the L2-3 disc space or midpoint of the L3 vertebra. All 30 of these patients had borderline low-lying conus without other associated abnormalities. Filar cyst was noted in 36 of 337 patients (10.6%), without other associated abnormalities. No patient underwent surgery associated with a risk of neurological problems within a follow-up period of 10-37 months.

CONCLUSIONS

Although screening US in infants with simple sacral dimple yielded benign imaging findings, the presence of FT lipoma was common in these infants. Therefore, it is necessary to carefully observe changes in echogenicity during measurement of FT thickness on US. All FT lipomas were low risk and had no associated abnormalities, such as cord tethering or low-lying conus.

[Tethered cord syndrome in children: about a case]

Le syndrome de la moelle attachée est un ensemble de symptômes neurologiques dû à une traction axiale constante ou intermittente du cône terminal de la moelle spinale, fixé en position caudale anormale. Il s'agit d'une lésion congénitale rare dont les symptômes peuvent s'exprimer qu'à l'âge adulte. Nous rapportons un cas clinique chez un garçon de 10 ans découvert à la suite d'une incontinence vésicale et anale qui a été confirmé par une imagerie par résonnance magnétique lombo-sacrée. Il a bénéficié d'une libération neurochirurgicale du cône terminal par un abord postérieur. L'évolution a été marquée par une amélioration des troubles sphinctériens. Ce cas est suivi d'une revue de littérature sur le sujet. Ce cas met l'accent sur l'intérêt de l’imagerie par résonance magnétique (IRM) dans le diagnostic de cette affection.

Diagnostic value of spinal ultrasound compared to MRI for diagnosis of spinal anomalies in pediatrics

Background

Spinal dysraphism (SD) is a spectrum of congenital disorders. MRI is the gold standard technique for diagnosis of SD. Spinal ultrasonography (USG) can be used as a screening tool for SD in infants. The purpose of our study is to assess the diagnostic value of spinal USG in the diagnosis of spinal dysraphism in pediatrics compared to MRI as a gold standard technique. Our prospective, cross-sectional study involved 45 infants and children with suspected spinal dysraphism. All patients were subjected to supervision of their medical history, full neurological examination, spinal ultrasonography and anatomical spine assessment by conventional MRI examination including sagittal and axial T1W & T2W, sagittal & coronal STIR imaging. Comparison of spinal USG with MRI findings was done.

Results

There is excellent overall agreement between MRI and ultrasound diagnosis in the evaluation of spinal cord morphology and bony elements in patients aged ≤ 2 years old (κ = 0.96 and 0.98) respectively, and fair overall agreement between MRI and ultrasound diagnosis (κ = 0.58) in patients aged > 2 years old. The accuracy of spinal USG in diagnosis of spinal dysraphism in patients aged ≤ 2 years old was as the following: specificity (94.5–100%), sensitivity (84.3100%), PPV (86.7–100%) and NPV (85.7–100%), as compared to MRI.

Conclusion

Spinal ultrasound can be used as a first-line screening investigation for SD; patients with USG abnormalities proceed to MRI. Spinal ultrasound is of no worthy value after the age of bone ossification, and MRI is the best modality of diagnosis in older pediatrics.

Acute presentations of intradural lipomas: case reports and a review of the literature

BACKGROUND

Lumbosacral lipomas (LLs) may remain asymptomatic or lead to progressive neurological deterioration. However, sudden neurological deterioration is a rare and severe event. Herein, we report rare occurrences of sudden clinical deterioration in two previously asymptomatic children harbouring intradural LLs without dermal sinus tracts or signs of occult dysraphism. A review of the pertinent literature is also included.

CASE PRESENTATION

One child exhibited acute deterioration because of an epidural abscess associated with a filar lipoma without a sinus tract (probably caused by haematogenous spreading from a respiratory tract multiple infection), and the other child exhibited acute deterioration because of a very large, holocord syringomyelia-like cyst associated with a small conus lipoma. Both patients were 4 years old. In case #2, a previously undetected, severe tethered cord (conus at the S3-S4 level) was also present. A complete recovery was attained after an urgent surgical operation in both cases (in addition to targeted antibiotic therapy in case #1). All cases of deterioration in the literature were caused by abscess formation in dermal sinus tracts.

CONCLUSIONS

Prophylactic surgery may be indicated even in asymptomatic children that have tethered cord and surgically favourable LLs (small dorsal and filar LLs), especially if the conditions are associated with progressive syringomyelia. Similarly, intradural dermal sinus tracts should be regarded as surgery-indicated, even if the conus is in its normal position and the patient is asymptomatic because there is a consistent risk of severe, infection-related complications. Finally, asymptomatic patients with filar LLs and a normally located conus can be candidates for surgery or an accurate clinical and radiological follow-up.

Filar cysts in rare cases may progress in size, particularly when associated with filar lipoma

PURPOSE

Filar cysts (FCs) are detected incidentally on ultrasonography (US) of the neonatal spine. Their clinical significance has not been widely discussed in the literature because FCs are usually asymptomatic. This study aimed to investigate the clinical features of FCs and distinguish FCs that warrant attention.

METHODS

We retrospectively analyzed 396 patients with lumbosacral skin stigmata. Patients who were younger than 1 month old at reference underwent US initially, and those older than 1 month of age underwent magnetic resonance imaging (MRI) at the age of 5-12 months. Patients with an FC in the US underwent subsequent MRI at the age of 5-12 months. Patients with an FC were followed clinically for at least 3 years.

RESULTS

FCs were identified in 56 (14.1%) patients. Of the 195 children who underwent US initially, FCs were detected in 49 (25.1%) children. FCs were detected in seven children who underwent MRI initially. Of the 50 children with FCs who underwent MRI at the age of 5-12 months, FCs in 20 patients (40%) showed natural regression and FCs in 30 patients (60%) remained. Two of these 30 patients showed progression in size of the FC, and in both cases, the FCs were associated with a filar lipoma; however, the resected cysts were not neoplastic and did not have obvious clinical significance.

CONCLUSIONS

Our study characterizes clinical features of filar cysts. Two-thirds of FCs remained in late infancy. The best sequence of MRI to follow-up FCs is heavily T2-weighted images.

Optimal Timing of Spinal Ultrasound Evaluations for Sacral Dimples in Neonates: Earlier May Not Be Better

OBJECTIVES

A spinal ultrasound (US) evaluation during the immediate postnatal period may have limited ability in evaluating filum thickness because of the spinal cord pulsation caused by a crowded subarachnoid space and the cerebrospinal fluid deficiency during this period. This study aimed to determine the optimal timing of spinal US to evaluate sacral dimples in neonates.

METHODS

This study included 585 neonates who had a clinically suspicious sacral dimple and underwent spinal US examinations between January 2015 and August 2017. Patients were classified into 1 of 2 groups based on whether measurements of all parameters were possible (group A) or not (group B). Neonatal and maternal clinical factors, including the antenatal history and US parameters, were compared between groups.

RESULTS

Group A included 443 patients, and group B included 82. Patients in group B were significantly younger (6.2 versus 31.0 days), had a younger corrective age (38.9 versus 42.5 weeks), and had a smaller body weight (3.1 versus 4.6 kg) than those in group A (all P < .005). However, no statistically significant differences were found in other patient or maternal factors (P > .05 for all). The pulsation of the conus medullaris and nerve roots of the cauda equina (14.6% versus 100%), thickening and echogenicity of the filum terminale (2.4% versus 100%), and the presence of a normal subarachnoid space (18.3% versus 100%) were significantly more difficult to detect in group B than in group A (all P < .001).

CONCLUSIONS

For an accurate evaluation, which can reduce unnecessary confusion and costs, spinal US can be delayed until neonates grow beyond 31 days, with a corrected age of older than 42.5 weeks and body weight of greater than 4.6 kg.

A method for quantitative 2-dimensional sonographic analysis of the fetal conus medullaris position

OBJECTIVE

This study explored the use of 2-dimensional (2D) ultrasound scans for the quantitative assessment of the fetal conus medullaris (CM) position and its correlation with gestational age (GA).

METHODS

This was a prospective study. We identified the first sacral vertebra (S1) by intersection of 2 lines in 2D scans, then counted upward from S1 to determine the CM level and recorded the number of ossified sacral vertebral bodies. A quantitative assessment of the CM position was performed by measuring the distance between the CM and the midpoint of the S1 (CM-S1). The correlation between the CM-S1 distance and GA was evaluated.

RESULTS

We determined the CM level by identifying S1 first in 521 fetuses (GA, 20-38 weeks). The CM position in 70% of cases was at the L2 and L2-3 level, and at the L2 level or above after 37 weeks. The number of ossified sacral veterbral bodies was not consistent. CM-S1 measurements were easy to perform. A significant positive correlation between CM-S1 distance and GA was observed (R²  = .89, P < .05). The best-fit formula was: CM-S1 distance = 1.57 × GA - 16.43. The normal reference range was established and the fifth percentile was calculated for each GA.

CONCLUSIONS

S1 was easily identified, and the CM position relative to S1 was useful. There was a substantial correlation between CM-S1 and GA. Below the fifth percentile it was suggested that tethered cord may exist.

Spinal cord ultrasonography of the newborn

Ultrasound represents the first-line survey for the assessment of spinal cord development abnormalities. In fact, within 6 months of life, the non-ossification of neuronal arcs provides an excellent acoustic window that allows a detailed depiction of the spinal canal, its content and of the surrounding soft tissues. Nevertheless, an accurate ultrasound examination requires a complete knowledge of the anatomy, the condition of normality, the frequent anatomical variants and the main pathologies involved. This review is intended to briefly summarize the US technique, the main clinical indication and the key notions that could help to properly perform this type of ultrasound examination.

Medulloblastoma in association with sacral agenesis; a case report

Medulloblastoma is a congenital brain tumor which can be associated with different congenital anomalies. However, coincidence of cerebellar medulloblastoma with sacral agenesis has not been reported so far. A variety of genetic and/or environmental predisposing factors have been proposed for both diseases. Herein, an unprecedented coincidence of these two conditions is presented. A neonate was born with lumbosacral agenesis, paraplegia, and atrophic legs, and he developed medulloblastoma with three ventricular hydrocephalus 3 years later. Different aspects regarding the embryology and etiology of both ailments are discussed, assuming the possibility that the same genetic and/or environmental risk factors may have played a part in both conditions.

Occult spinal dysraphisms in newborns with skin markers: role of ultrasonography and magnetic resonance imaging

PURPOSE

The purpose of this paper is to investigate occult spinal dysraphisms (OSD) using lumbar ultrasonography (LUS) in newborns presenting with specific skin markers or sacrococcygeal dimple.

METHOD

From 2012 to 2015, we performed LUS in newborns with cutaneous stigmata and/or sacroccygeal dimple. Magnetic resonance imaging (MRI) was performed in all patients with abnormal ultrasound or features of neurological involvement in order to detect spinal lesions.

RESULTS

We prospectively evaluated 475 newborns who presented cutaneous stigmata performing LUS during their 4 weeks of life though 439 completed the study. All patients had a follow-up of almost 12 months. Of these, 39 presented abnormal ultrasonography and underwent MRI. In this group, spinal dysraphism was confirmed in 12 patients. When considering skin markers, dermal sinus correlated with higher risk of spinal cord lesions, on the other hand the presence of simple sacral dimple alone denoted a very low risk of occult spinal dysraphism. The simultaneous presence of more skin markers and/or the presence of lumbar ultrasonography abnormality regarding the level of the conus, pulsatility, and the position of the cord, thickness of the filum terminale, or the presence of an intratecal mass, lipoma, or dermal sinus tract indicated the necessity to perform MRI in order to detect spinal cord abnormalities because of higher risk of spinal lesions.

CONCLUSION

LUS in newborns with specific skin markers is a valid method to select patients in which MRI can be performed to detect OSD. The presence of a simple sacral dimple alone is a negligible marker for occult neural pathology while the presence of isolated dermal sinus or more than one cutaneous marker could be considered indicative of higher risk of spinal dysraphism.

Diagnostic value of ultrasonography in spinal abnormalities among children with neurogenic bladder

Background

Nowadays, magnetic resonance imaging (MRI) is the gold standard for evaluation and diagnosis of spinal cord abnormalities, which are considered among the leading causes of neurogenic bladder; however, MRI is a costly imaging method and is not available at all health centers. Sporadic studies have shown the alignment of MRI with ultrasonography results in diagnosis of spinal abnormalities; although none of these studies has expressed the diagnostic value of ultrasonography.

Objective

The aim of this study was to evaluate the diagnostic value of ultrasonography in detection of spinal abnormalities in children with neurogenic bladder.

Methods

This is a cross-sectional study carried out from January 2014 to November 2015 on patients with neurogenic bladder referred to Department of Radiology, Dr. Sheikh Hospital, Mashhad University of Medical Sciences, Mashhad, Iran. All patients underwent sonography of the spinal cord and soft-tissue masses; also, a spinal MRI scan was performed. The existence of spina bifida, sacral agenesis, posterior vertebral arch defects, mass, tethered cord, myelomeningocele, lipoma and fatty infiltration, dural ectasia, hydromyelia and syringomyelia, and diastomatomyelia was recorded during each imaging scan. Chi-square and Fisher’s tests were used for data analysis using SPSS 19.0 software, and the sensitivity and specificity of ultrasonography findings were calculated by MedCale 26 software.

Results

Forty patients with neurogenic bladder (22 males/18 females), with an average of 25.73±19.15 months, were enrolled. The most common abnormality was found in patients’ MRI was tethered cord syndrome (70%). There was a significant relationship between ultrasonographic and MRI findings in spina bifida abnormalities (p=0.016), sacral agenesis (p=0.00), tethered cord (p=0.00), myelomeningocele (p=0.00), and lipoma and fatty infiltration (p=0.01). Ultrasonography had a sensitivity of 20.0%–100% and a specificity of 85.7%–100% depending on the detected type of abnormality.

Conclusion

It seems that ultrasonography has an acceptable and desirable sensitivity and specificity in the diagnosis of most of the spinal cord abnormalities in children with a neurogenic bladder.

An intradural, subpial lipoma

Introduction - patients: Intradural lipomas are rare congenital tumors. A case of intradural lipoma in the absence of any congenital spinal anomalies is reported. Patient presented with spinal cord compression syndrome. Methods - results - conclusions: Treatment of this disorder is still controversial.

Sonographic spinal imaging of normal anatomy, pathology and magnetic growing rods in children

The wide availability of ultrasound, along with its lack of ionizing radiation burden and need for sedation for most exams, often make sonography the first line in the imaging evaluation of children. The developing osseous anatomy of the spine in young infants provides a distinct window allowing for a detailed depiction of the spinal canal and its contents, which is not present in older children or adults. Here we review the clinical indications, sonographic technique, normal anatomy and pathology for imaging the lumbosacral spine in neonates and young infants. Additionally, we review the procedure for ultrasound assessment of the lengthening of magnetically controlled growing spinal rods, which allows orthopedists and radiologists to evaluate the effectiveness of distraction procedures of this hardware without the use of ionizing radiation.

Ultrasonographic features of the normal filum terminale

Purpose

The filum terminale (FT) is a fibrous band that connects the conus medullaris to the posterior body of the coccyx. Considering the advances of ultrasonography (US) technology and improvements in the resolution of US images, we aimed to re-establish the US features of the normal FT in infants younger than 6 months of age.

Methods

We retrospectively reviewed 30 spinal US scans, stored as video clips. The internal structure of the FT and the marginal echogenicity of the FT were assessed, and transverse and longitudinal US were compared.

Results

On US, a central echogenic line was defined in 18 (60%) normal FTs; however, there was no visible internal structure in 12 cases (40%). The marginal echogenicity of the FT was hyperechoic in eight cases (27%) in comparison with the cauda equina and was isoechoic in 22 cases (73%). In differentiating the normal FT from the surrounding nerve roots, transverse US was superior in 18 cases (60%), while longitudinal US was superior in two cases (7%).

Conclusion

On US, the central canal of the FT was defined in 60% of normal FTs. Hyperechoic marginal echogenicity and the use of transverse US were helpful in distinguishing the normal FT from the nerve roots of the cauda equina.

Ultrasonography of the pediatric hip and spine

Ultrasonography (US) is a useful screening method for the diagnosis of developmental dysplasia of the hip (DDH) and congenital spinal anomalies in infants. In addition, US is a useful, noninvasive imaging modality for the diagnosis of transient synovitis in children. The early detection of DDH leads to a better prognosis without surgical intervention. Moreover, spinal US allows the detection of congenital malformations and can also demonstrate normal anatomy and normal variants that may resemble disorders. Therefore, radiologists should be familiar with the sonographic anatomy of the normal infant hip, scanning and measurement techniques for DDH, the US features of transient synovitis in children, spinal US techniques, and the US features of normal anatomical structures, normal variants, and congenital spinal anomalies.

Sacral agenesis: a pilot whole exome sequencing and copy number study

Background

Caudal regression syndrome (CRS) or sacral agenesis is a rare congenital disorder characterized by a constellation of congenital caudal anomalies affecting the caudal spine and spinal cord, the hindgut, the urogenital system, and the lower limbs. CRS is a complex condition, attributed to an abnormal development of the caudal mesoderm, likely caused by the effect of interacting genetic and environmental factors. A well-known risk factor is maternal type 1 diabetes.

Method

Whole exome sequencing and copy number variation (CNV) analyses were conducted on 4 Caucasian trios to identify de novo and inherited rare mutations.

Results

In this pilot study, exome sequencing and copy number variation (CNV) analyses implicate a number of candidate genes, including SPTBN5, MORN1, ZNF330, CLTCL1 and PDZD2. De novo mutations were found in SPTBN5, MORN1 and ZNF330 and inherited predicted damaging mutations in PDZD2 (homozygous) and CLTCL1 (compound heterozygous). Importantly, predicted damaging mutations in PTEN (heterozygous), in its direct regulator GLTSCR2 (compound heterozygous) and in VANGL1 (heterozygous) were identified. These genes had previously been linked with the CRS phenotype.

Two CNV deletions, one de novo (chr3q13.13) and one homozygous (chr8p23.2), were detected in one of our CRS patients. These deletions overlapped with CNVs previously reported in patients with similar phenotype.

Conclusion

Despite the genetic diversity and the complexity of the phenotype, this pilot study identified genetic features common across CRS patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12881-016-0359-2) contains supplementary material, which is available to authorized users.

Congenital anomalies of lumbosacral spine: A pictorial review

Congenital malformations of the lumbosacral spine include spinal dysraphism and caudal anomalies. Most often, these malformations are discovered prenatally or in early infancy, but some are not diagnosed until late childhood or adulthood. The purpose of this pictorial review is to illustrate the multi-modality imaging characteristics in these complex anomalies and to provide a systematic radiological approach aiming at improving diagnostic accuracy.

Prenatal diagnosis and assessment of congenital spinal anomalies: Review for prenatal counseling

The last two decades have seen continuous advances in prenatal ultrasonography and in utero magnetic resonance imaging. These technologies have increasingly enabled the identification of various spinal pathologies during early stages of gestation. The purpose of this paper is to review the range of fetal spine anomalies and their management, with the goal of improving the clinician’s ability to counsel expectant parents prenatally.

Sonography of the Tethered Cord A Case Study

There are many clinical indications for neonatal spinal imaging. The advantages of real-time imaging and improved spatial resolution have broadened the field of ultrasound's applicability to include the neonatal spinal cord. The authors present a case study of a tethered cord in which sonography was the initial imaging exam of choice, and magnetic resonance imaging confirmed the diagnosis. The authors also review the sonographic characteristics and discuss the pathogenesis of a tethered spinal cord.

Congenital malformations of the brain and spine

In this chapter we briefly address the most common congenital brain and spinal anomalies as well as their most salient imaging, especially magnetic resonance, findings. Some of them, such as Chiari II, and open spinal defects, have become relatively rare due to their detection in utero and repair of the spinal malformation. Regardless of the type of brain anomaly, the most common clinical symptoms are mental retardation, hydrocephalus, and seizure; the latter two may need to be surgically and medically addressed. The most commonly found spinal congenital anomalies include the filum terminale lipoma which is generally asymptomatic and incidental and the caudal regression syndrome for which no primary treatment exists. Any spinal congenital anomaly may present in adulthood as a consequence of spinal cord tethering and/or development of syringomyelia.

Optimal Filum Terminale Thickness Cutoff Value on Sonography for Lipoma Screening in Young Children

OBJECTIVES

The purpose of this study was to evaluate the normal thickness of the filum terminale on sonography and suggest an optimal cutoff value for filum terminale lipoma screening in young children.

METHODS

We retrospectively reviewed lumbosacral sonograms and magnetic resonance images from children younger than 36 months that were obtained between January 2013 and June 2014. The filum terminale thickness on sonography and the presence of fat in the filum terminale on magnetic resonance imaging were evaluated.

RESULTS

From 111 children (mean age ± SD, 3.6 ± 3.0 months), 49 did not have abnormal lesions (normal group), and 62 had fat infiltration in the filum terminale (lipoma group). The filum terminale was thicker in the lipoma group than the normal group (1.5 ± 0.5 versus 0.9 ± 0.2 mm; P < .001). Filum terminale thickness also showed significance in a multivariable analysis with sex and age (odds ratio per 0.1-mm unit, 2.754; P < .001) and in propensity score matching for age (P < .001). The optimal cutoff value for filum terminale lipoma screening was 1.1 mm, with 94% sensitivity and 86% specificity.

CONCLUSIONS

The conventional cutoff value of 2 mm for a thickened filum terminale on sonography can be too thick. We suggest an optimal cutoff value of 1.1 mm for lipoma screening in young children.

Spine ultrasound imaging in the newborn

Ultrasound of the spine in the neonate is widely used as the initial modality to evaluate spinal canal anatomy, anatomical variants, and congenital malformations. The spinal canal and its contents are best visualized in the newborn and young infant owing to incomplete ossification of the posterior vertebral elements.

Anorectal Malformations: Finding the Pathway out of the Labyrinth

Anorectal malformations (ARMs) are a complex group of congenital anomalies involving the distal anus and rectum, as well as the urinary and genital tracts in a significant number of cases. Most ARMs result from abnormal development of the urorectal septum in early fetal life. In most cases, the anus is not perforated and the distal enteric component ends blindly (atresia) or as a fistula into the urinary tract, genital tract, or perineum. ARMs are also present in a great number of syndromes and associations of congenital anomalies. The classification of ARMs is mainly based on the position of the rectal pouch relative to the puborectal sling, the presence or absence of fistulas, and the types and locations of the fistulas. All of this information is crucial in determining the most appropriate surgical approach for each case. Imaging studies play a key role in evaluation and classification of ARMs. In neonates, clinical and radiologic examinations in the first 3 days of life help determine the type of ARM and the need for early colostomy. In older children, preoperative pelvic magnetic resonance imaging is the most efficient diagnostic method for evaluating the size, morphology, and grade of development of the sphincteric musculature.

Spinal cord malformations

Malformations of the spinal cord are one of the most frequent malformations. They should be clearly divided into two completely different families of malformations: open dysraphisms and occult dysraphisms. Open dysraphism mostly consists in myelomeningocele (MMC). Its incidence is 1/1000 live births with a wide variation. Folic acid supplementation has been shown to reduce its risk. In most cases, the diagnosis is done prenatally by serum screening and ultrasound and may lead to termination of pregnancy. In case of decision to continue pregnancy, surgical treatment must be achieved during the first days of life, and in 50 to 90% of cases, a ventricular shunt must be installed. The follow-up of these children must be continued throughout life looking for late complications (Chiari II and syringomyelia, vertebral problems, neuropathic bladder, tethered cord). Occult dysraphisms are a heterogeneous group of malformations. Lipomas (filum and conus) are the most frequent and their treatment remains controversial. Diastematomyelia, neurenteric cysts, dermal sinus, and more complex forms (Currarino syndrome) belong to this group. Most of them can and must be diagnosed prenatally or at birth by careful examination of the lower back for the cutaneous stigmata of the disease to decrease the risk of neurological, urological, or orthopedic permanent handicap.