Ultrasonography and magnetic resonance imaging evaluation of pediatric spinal anomalies

Cloacal Dysgenesis Sequence in a Preterm Neonate

BACKGROUND Cloaca malformations result from a disproportion of apoptosis, cell growth, and maturation. The range of cloacal malformations is extensive and diverse, with a lack of a straightforward classification system. Cloacal dysgenesis sequence (CDS), also known as urorectal septum malformation sequence, is a rare cloaca variant described as the absence of a perineal orifice. Prenatal magnetic resonance imaging and antenatal ultrasounds may reveal a cloacal malformation; however, many patients are not diagnosed with cloacal malformation until birth. CASE REPORT We present a case of a female neonate delivered by a 23-year-old G2P1T1A0L0 mother who had received comprehensive prenatal care. During pregnancy, bilateral multicystic dysplastic kidneys were identified prenatally, leading to the in utero placement of a vesicoamniotic shunt. The physical exam revealed a distended abdomen with reduced abdominal musculature and laxity, ascites, a vesicoamniotic shunt in place, absent urethra, ambiguous genitalia with no vaginal opening, no perineal opening, and clubfoot. Abdominal radiograph showed findings consistent with significant abdominal ascites. An exploratory laparotomy was performed that included diverting colostomy, mucous fistula creation, tube vaginostomy, removal of the vesicoamniotic shunt, and suprapubic tube placement. The patient recovered well from this operation with no complications. CONCLUSIONS CDS is an uncommon condition in pediatric patients, and although sonographic findings can reveal urinary tract abnormalities, prenatal imaging might not always identify CDS. Our case underscores the uniqueness of the case and the significance of early detection and immediate medical and surgical intervention.

MR Protocols for Paediatric Neurosurgical Common Conditions: An Update Guide for Neurosurgeons

The biggest challenge for clinicians and surgeons when it comes to radiological examinations is the ability to request the right modalities and to understand the strengths and limitations of each modality. This is particularly important in paediatric neurosciences where despite magnetic resonance imaging (MRI) being the main imaging modality, there are several protocols, technical limitations of specific scanners and issues related to sedation that need to be taken into account. In this chapter, we describe a simple approach for six common neurosurgical conditions to guide the paediatric neurosurgeons in requesting the right MR protocol and understanding the rationale of it.Paediatric neuro-oncology, epilepsy and neck/skull base protocols are discussed elsewhere in this book and therefore will not be a focus in this chapter (Bernasconi et al., Epilepsia 60:1054-68, 2019; D'Arco et al., Neuroradiology 64:1081-100; 2022; Avula et al., Childs Nerv Syst 37:2497-508; 2021).

Role of ultrasonography in screening of spinal dysraphism in infants at risk

Background

Spinal dysraphism (SD) encompasses congenital spinal defects that result from inappropriate fusion of the different midline osseous, mesenchymal, and neural elements. The primary tools for diagnosis of SD are both spinal ultrasonography (USG) and magnetic resonance imaging (MRI). Spinal USG is growingly being used as an initial screening modality with sensitivities and accuracies equivalent to those of MRI. Anorectal malformations (ARM) have ultimate association with many other congenital abnormalities, of which spinal dysraphism is one of the most common. The main aim of study was to assess the diagnostic accuracy of spinal USG as a screening modality in comparison with MRI in infants with closed spinal dysraphism. We also endeavored to highlight the associated spinal dysraphism radiological findings in patients with either ARM or back cutaneous stigmata.

Results

Our prospective diagnostic comparative study included 33 patients, all of whom underwent both MRI and USG. Both MRI and USG showed appreciable agreement in the assessment of spinal dysraphism. In comparison with the gold standard MRI, spinal USG revealed comparable diagnostic metrics: specificity (98.6–100%), sensitivity (66.6–91.6%), PPV (90–100%) and NPV (94.1–98.7%) in diagnosis of different types of spinal dysraphism. The main clinical presentation of nineteen patients was anorectal malformation (ARM), 11 of whom (57.9%) had evidence of associated spinal dysraphism. The most common types of ARM were cloacal malformation, recto-urethral fistula, and rectal atresia with no fistula. On the other hand, sixteen patients were mainly presented with back cutaneous stigmata, 11 of whom (68.8%) had associated spinal dysraphism. The most common presenting cutaneous stigmata were low back swelling and atypical dimples.

Conclusion

The front-line screening modality for infants with closed SD should be spinal USG, however, its main limitation is the restrained time window in the first 6 months of life. Infants with ARM should be screened for spinal anomalies, especially those with high and complex types. Infants with high-risk back cutaneous stigmata should be similarly screened, as well.

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

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

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.

Perioperative ultrasound imaging versus magnetic resonance imaging in management of lumbosacral spinal dysraphisms

Objectives

The purpose of this study was to correlate lumbosacral spinal ultrasound (LUS) and magnetic resonance imaging (MRI) findings in patients with lumbosacral spinal dysraphisms to evaluate the value of LUS in diagnosis, intraoperative use, and during follow-up of those patients.

Methods

A total of 24 patients aged up to 6 years old were operated for lumbosacral spinal dysraphisms at the Neurosurgery Department of Zagazig University hospitals during the period from January 2017 to August 2018. All patients were investigated preoperatively, intraoperatively, and on follow-up by LUS to compare the data with preoperative and follow-up MRI of the spine.

Results

The median age was 11 months at the time of surgery. The most common anatomical description from the LUS study was thickened filum (18 cases). Using MRI findings as the standard reference, the sensitivity of LUS in detecting a thickened filum was 77.8% preoperatively and 62.5% postoperatively, with a specificity of 100%. The sensitivity and specificity of detecting conus level, solid masses, and cystic masses were 100%.

Conclusions

Lumbosacral spinal dysraphisms can be evaluated well by ultrasound imaging in age group up to 6 years old with 100% specificity (true negative) in comparison with MRI.

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.

Magnetic Resonance Imaging in Paediatric Spinal Dysraphism with Comparative Usefulness of Various Magnetic Resonance Sequences

INTRODUCTION

Spinal dysraphism occurs due to failure of fusion of parts along dorsal aspect of midline structures lying along spinal axis from skin to vertebrae and spinal cord. Congenital spinal anomalies may be minimal and asymptomatic like spinal bifida occulta, or severe with marked neurological deficits like Arnold-Chiari malformation or caudal regression syndrome. Magnetic Resonance Imaging (MRI) is the modality of choice to diagnose mild to severe spinal dysraphism.

AIM

To diagnose type and extent of clinically suspected spinal anomalies by MRI scan and to compare various sequences for identifying neural tissue and fatty tissue in anomalies.

MATERIALS AND METHODS

Fifty paediatric patients referred with clinical suspicion of spinal anomalies for MRI scan to radiodiagnosis department and diagnosed as having spinal dysraphism on 1.5 Tesla MRI Scan, were included in this observational analytic study. Various MRI sequences were taken in multiple planes. MRI findings of spinal dysraphism were compared with detailed clinical examination or surgical findings. Osseous anomalies like spina bifida occulta were confirmed by radiographs or CT scan.

RESULTS

Out of 50 patients, type II Arnold-Chiari Malformation (34%), Spina Bifida Occulta (22%) and Diastematomyelia (18%) were common anomalies. MRI findings were well correlated with surgical findings in 20 operated cases. Nerve roots with/ without neural placode in thecal sac/outpouching were detected in combination of 3D HASTE myelographic sequence with SE/ TSE T1W sequence in 24 cases; which was significantly high as compared to combinations of SE/TSE T1W sequence with TSE T2W, with STIR and with Single Shot Myelographic sequence {p-value 0.002, < 0.001 and 0.008 respectively}. Fatty component was present in dysraphism in five cases, commonly as isolated anomaly; which was detected by combination of STIR and SE/TSE T1W sequences in all five cases.

CONCLUSION

Paediatric spinal dysraphism and associated malformations are accurately diagnosed on MRI scan. MR myelographic 3D-HASTE and STIR sequences should be a part of protocol to evaluate spinal dysraphism.