Occult spinal dysraphism in infants: screening with high-resolution real-time ultrasound

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.

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.

Ecografia computerizzata della colonna vertebrale del neonato

L'ecografia computerizzata costituisce attualemente un'utile e relativamente semplice metodica di studio del canale vertebrale e del suo contenuto, nel neonato a termine e pretermine e nel lattante normale. Viene riportata l'esperienza personale in casi normali, impiegando un apparecchio Acuson 128. Vengono discussi i vantaggi ed i limiti di tale metodica nella rappresentazione dell'anatomia del canale spinale, specie a livello lombo-sacrale, e nello screening della patologia disrafica spinale del primo anno di vita.

L'ecotomografia spinale nello studio del midollo ancorato

Scopo del presente lavoro è puntualizzare il ruolo dell'ecografia nello studio del midollo ancorato che rappresenta un'aspetto comune a molta della patologia spinale infantile e può prestarsi ad un'analisi globale dello stato dell'arte dello studio ecografico del midollo spinale, alla luce dell'esperienza acquisita negli anni e del continuo progresso tecnologico.

Dopo qualche cenno storico e alcune puntualizzazioni di carattere tecnico e di anatomia ecografica e stabilita la principale indicazione all'ecografia spinale nel neonato-lattante consistente nella ricerca delle spine bifide occulte, sospettate nel caso di masse posteriori ricoperte dalla cute o di fossette/seni dorsali, spesso associate a midollo ancorato, abbiamo illustrato i segni generici ecografici di midollo ancorato ed i differenti rilievi e potenzialità della metodica nel bilancio delle varie masse caudali responsabili dell'ancoraggio del midollo. L'eco non presenta alcun interesse nello studio diagnostico dei disrafismi spinali aperti mentre potrebbe rivelarsi utile nella ricerca postoperatoria di un eventuale riancoraggio midollare, valutato in base all'assenza della fisiologica pulsatilità del midollo. A tal proposito abbiamo recentemente effettuato una comparazione tra presenza o meno di motilità spinale valutata ecograficamente e presenza di segni clinici in pazienti precedentemente operati per disrafismo spinale.

In conclusione, lo studio ecografico del midollo spinale del neonato-lattante, pur presentando grossi limiti, trova giustificazione nella innocuità, nella facilità d'uso e nella possibilità di ottenere immagini in tempo reale. La presenza o il solo sospetto clinico di patologia disrafica impongono comunque sempre il completamento del bilancio diagnostico mediante RM/TC.

Ultrasonography reveals a high prevalence of lower spinal dysraphism in children with urogenital anomalies

BACKGROUND

Lower spinal dysraphism is frequently reported in anorectal anomaly combined with urogenital anomalies. The prevalence of the spinal dysraphism has not been comprehensively studied in children with simple urogenital anomalies. We evaluated the prevalence of the spinal dysraphism using ultrasound data of the lumbosacral area in children with urogenital anomalies.

METHODS

Lumbosacral ultrasound images of 259 children who underwent urological surgery with simple urogenital anomalies were reviewed by an ultrasound-specialized radiologist. The primary outcome measures were the conus medullaris (CM) level and the thickness of the filum terminale. The spinal ultrasonographic findings that were assessed in children showed abnormal spinal findings compared with the other children having normal findings. Two years later, the follow-up telephone interviews were made with the parents of the children with abnormal findings.

RESULTS

Eighteen children were differentiated as the abnormal finding group. They were suspected of spinal cord tethering. The level of CM was lower, and the filum terminale was thicker compared to the normal group [L2(lower (L)) vs. L1(L), 2.2 mm vs. 0.8 mm]. Of eighteen children, four were confirmed as tethered spinal cord with lipoma on magnetic resonance imaging by the time of surgery, and two were strongly suspected of occult spinal dysraphism (OSD) based on ultrasound findings and follow-up interviews.

CONCLUSIONS

The prevalence of OSD in children under 24 months of age with simple urogenital anomaly was higher than what was reported for the general population. Ultrasound examination of spinal structures before caudal block in children with urogenital anomaly should be considered.

Imaging of congenital anomalies and variations of the caudal spine and back in neonates and small infants

Spinal dysraphisms are categorized in open dysraphisms with prominent abnormal nervous tissue above the skinlevel and closed dysraphisms with a skin covered malformation. Especially the occult dysraphisms are marked by suspect skin masses and other dermal anomalies. The purpose of this review is to demonstrate the indications and spectrum of spinal sonography in neonates and infants. In comparison typical dysraphisms are demonstrated in sonography and MR Imaging. We demonstrate the value of ultrasound in comparison to MRI and describe a usefull handling of the methods in neonates and infants. The differentiation between the potentially dangerous dimples associated with dermal sinus, which can lead to meningitis and the harmless coccygeal dimple in the cranial gluteal cleft is presented. An inconspicious examination does not need a further imaging, but suspicious results of sonography need an MR imaging dependent of clinical conditions. Neurologically conspicious infants need MR imaging completed by sonography. Great advantages of sonography are the real time examination and the potential to show oscillations of the conus, filum and cauda equina in M-mode-imaging.

Spinal cord sonography in newborns: anatomy and diseases

Sonography of the spinal cord is a relatively recent acquisition that makes it possible to evaluate the content of the vertebral canal and study its pathologies. The aim of this study was to verify the reliability of ultrasound images by comparing them with magnetic resonance ones in healthy controls as well as in patients referred to us between 1991 and 2004. In this period, we studied 436 newborns: 88 without any suspicion of disease as normal controls, and 348 with suspected congenital diseases or in order to screen the children of diabetic mothers, a group that has shown an increased incidence of dysraphism. After explaining normal sonograms, we describe the pathological pictures observed in the 12 pathological cases in our series: conus hypomobility in five cases; lack of visualization of the conus medullaris in one case; and an enlarged ependymal canal in six cases. Four cases presented all three pathological conditions, and seven the association of two pathologies. All of these patients also underwent magnetic resonance imaging (MRI), which confirmed the ultrasound findings in four cases: three cases of enlarged ependymal canal and one of tethered cord hypomobility of the roots with an associated lipoma; the MRI findings were normal in the other seven cases. Sonography was highly specific but not very sensitive, because it is partially conditioned by patient collaboration. Nevertheless, subsequent MRI confirmed 37% of the suspected pathological cases. The ultrasound resolution of both normal and pathological spinal cord structures was particularly clear. The images were similar, easily comparable and often identical to the MRI results, although MRI was certainly more sensitive. The advantages of sonography are its non-invasiveness, low cost, the virtually ubiquitous availability of ultrasound equipment, the simplicity and rapidity of the examination, and its specificity. We believe that the indications for its use are lumbo-sacral skin alterations, neurological disorders caused by congenital malformations, traumas due to childbirth or a lumbar puncture, occult dysraphism, all of the compressive spinal cord neo-formations involving nerves, the dura mater and vertebral bone and joint structures, and the screening of the newborns of diabetic mothers.

The value of ultrasonic examination of the lumbar spine in infants with specific reference to cutaneous markers of occult spinal dysraphism

AIM

To present part of the rationale behind the recent update to the M12 guideline in The Royal College of Radiologists' publication "Making the best use of a department of clinical radiology", 4th edition 1998, which stated that ultrasound was useful in screening for dysraphism in infants with cutaneous markers such as sacral dimple or hairy patch.

MATERIALS AND METHODS

Over a 10-year period a total of 223 infant lumbar spines were scanned, for various clinical indications. Forty of these patients had already had abnormalities detected antenatally by foetal ultrasonography. One hundred and eight-three patients had abnormalities detected on postnatal clinical examination; most of these had various cutaneous markers, some had other congenital abnormalities.

RESULTS

There were a total of 29 patients with dysraphism; 24 were detected antenatally and five postnatally. Of the five, two had two or more cutaneous markers and three had anorectal anomalies. All 86 of the patients with simple sacral dimples, pits or sinuses were normal.

CONCLUSION

As an isolated abnormality, simple dimples or pits are not useful markers of spinal dysraphism. The authors suggest a new imaging protocol, resulting in improved diagnostic efficiency.

Minor skin lesions as markers of occult spinal dysraphisms—prospective study

BACKGROUND

Neonates with occult spinal dysraphisms (OSDs) may not present any clinical manifestations, but may be associated to cutaneous stigmas that indicate dysraphism. Association of minor cutaneous stigmas (discreet skin lesions, most of which are not assessed) with OSD was investigated in this study, as well as the use of ultrasonography (US) as a screening method for those patients.

METHODS

Two thousand ten neonates were evaluated trough active search. Both the pediatrician and the neurosurgeon performed the search for the presence of cutaneous stigmas on the midline of the dorsal region. For all of them, the gestational age, type of delivery, gender, ethnicity, age of mother, and whether it was a high-risk gestation were recorded. Patients with skin lesions comprised the case group. For each case, another neonate of the same gender, gestational age, and ethnicity was selected as control. Both groups were evaluated with respect to personal, social, and medical information. Spinal US was performed in all case and control patients-if altered or inconclusive, it was complemented with magnetic resonance imaging (MRI).

RESULTS

Of the 2010 patients, 144 presented cutaneous stigmas. Of these, 8 had alterations to US (5.5%) and 6 to MRI. There were no alterations to US in the control group. The most frequent lesions were tufts of hair and dimples; through US, the most frequent findings were dermal sinuses.

CONCLUSIONS

The so-called minor skin lesions were not markers of OSD in the evaluated population. However, in 4 patients, US was decisive for the surgical decision. From the statistical point of view, there is no indication for complementary examinations in patients with minor cutaneous stigmas. However, because of the feasibility, simplicity, and low cost of the spinal US, the examination is justified in the benefits of early diagnosis, regardless of the need of immediate surgical treatment.

Diagnostic value of bed-side ultrasonographic evaluation by anterior approach in spine disorders? A preliminary report

A preliminary investigation was planned so as to evaluate the effectiveness of ultrasonography for bed- side evaluation of patients with suspected spinal pathology. Its application by anterior approach in 37 cases showed that herniated disc material, bone, epidural fat, scar tissue, tumoral masses and their relation to the interspace and dural sac could be visualized. A short description of the sonographic appearance of normal and pathological structures was also given in comparison to Computed Tomography or Magnetic Resonance images. Ultrasonographic examination was inadequate in five of the patients due to obesity, meteorism or diminution of the intervertebral disc space. Advantages of this technique are the availability almost in every hospital, the ease of obtaining images at various angles, avoiding the use of x-rays and the low price. The disadvantages are its relatively poor definition as compared to Computed Tomography or Magnetic Resonance Imaging and its inability to see through bone.

Evaluation of spinal ultrasound in spinal dysraphism

AIMS

The aims of this study were to evaluate the role of spinal ultrasound in detecting occult spinal dysraphism (OSD) in neonates and infants, and to determine the degree of agreement between ultrasound and magnetic resonance imaging (MRI) findings.

MATERIALS AND METHODS

Eighty-five consecutive infants had spinal ultrasound over 31 months. Of these, 15 patients (age 1 day-7 months, mean 40 days; nine male) had follow-up MRI. Ultrasound and MRI findings were correlated retrospectively.

RESULTS

Six out of 15 (40%) ultrasound examinations showed full agreement with MRI, seven of 15 (47%) had partial agreement, and two of 15 (13%) had no agreement. In the present series ultrasound failed to visualize: four of four dorsal dermal sinuses, three of four fatty filum terminales, one of one terminal lipoma, two of four partial sacral agenesis, three of four hydromyelia and one of 10 low-lying cords.

CONCLUSION

Agreement between ultrasound and MRI was good, particularly for the detection of low-lying cord (90%). Therefore we recommend ultrasound as a first-line screening test for OSD. If ultrasound is abnormal, equivocal or technically limited, MRI is advised for full assessment.

Cervicothoracic extradural arachnoid cyst: possible association with obstetric brachial plexus palsy

The association of cervicothoracic extradural arachnoid cysts and obstetric brachial plexus palsy has not previously been reported. We report two patients with this association. The first patient is a 9-month-old boy with left obstetric brachial plexus palsy that developed bilateral leg weakness at 6 months of age owing to compression of the spinal cord by a C6 to T8 left cervicothoracic extradural arachnoid cyst. The second patient is a 3-year-old girl with bilateral brachial plexus palsy and spastic paraparesis who had magnetic resonance imaging at 3 days of age that showed intraspinal cord injury and a cervicothoracic extradural arachnoid cyst compressing the spinal cord. We believe that the association of cervicothoracic epidural arachnoid cysts and obstetric brachial plexus palsy in these patients was causal and recommend that the possibility of a cervicothoracic epidural arachnoid cyst be considered in patients with brachial plexus palsy and evidence of spinal cord injury.

Spinal ultrasound in infants

This paper discusses the indications for spinal ultrasound, including its advantages and disadvantages compared with spinal MRI. The features and ultrasound findings both in normal infants and in those with spinal dysraphism are reviewed.

Spinal hamartomas: a distinct clinical entity

OBJECT

Congenital spinal hamartomas are defined as tumors of well-differentiated mature elements situated in an abnormal location. In this report, the authors document the clinical and pathological features of spinal hamartomas in 10 patients.

METHODS

Ten patients presented with midline dorsal malformations at birth, initially diagnosed as teratomas or myelomeningoceles. The locations of the masses were variable: two were located in the thoracic region, four at the thoracolumbar junction, two in the lumbar region, one at the lumbosacral junction, and one in the sacral region. The results of the neurological examination were normal in nine patients. All but one mass had intact skin and seven had palpable bone components. Neuroimaging studies revealed widening of the spinal canal, heterotopic bone located dorsally in some patients, and varying degrees of involvement of the intraspinal contents. During surgery, six patients were found to have involvement of the spinal cord or cauda equina. The pathological characteristics of the masses included three or more of the following: bone, cartilage, synovial membrane, urinary tract tissue, cyst wall, yellow or brown fat, and nerves. The well-differentiated cellular elements, which formed mature structures, along with the absence of primitive cellular components and neoplastic characteristics are more consistent with a diagnosis of hamartoma than teratoma.

CONCLUSIONS

In this series, the authors describe a lesion that is overt on physical examination, yet can have occult spinal canal involvement. Complete neurosurgical evaluation is essential to provide appropriate treatment and prognosis.

Human tails and associated spinal anomalies

Human tails have been described intermittently in the literature, typically as isolated cases with varying forms of malformation. Attempts have been made to differentiate "true" tails from "tail-like" appearances. Unless identified, underlying occult spinal disorders, mass effect, and/or tethering of the spinal cord may lead to progressive neurologic damage. We report three patients with "tails" and the associated spinal anomalies.

Distal spinal cord pathology in the VATER association

Herein the authors report the pathology of six cases of VATER association and tethered spinal cord that underwent operative intervention for removal of lipomas of the conusfilum terminale and/or release of the tethered cord. In five of the six patients, the excised filum terminale consistently showed excessive mature adipose tissue, normal blood vessels, small myelinated nerve fibers, and fibrous connective tissue. One patient had mature lobulated adipose tissue and vessels only. It is concluded that patients with the VATER association who present with distal spinal cord pathology consistently have abnormal involution of the filum terminale, the hallmark being an abnormal collection of mature fat, thickening of the filum, and extension of the fat into the conus medullaris.

Ultrasound assessment of congenital spinal anomalies presenting in infancy

Sonography of the infant spine can rapidly and safely exclude or confirm the presence of a congenital malformation. This article reviews the embryology of the spinal cord, abnormal and normal sonographic findings, and findings associated with occult dysraphic lesions. Patient selection for sonographic assessment is also discussed. Illustrations of normal anatomy and the more common dysraphic lesions are provided.

Prenatal sonographic diagnosis of diastematomyelia in a diabetic woman

Diastematomyelia is a structural anomaly which concerns primarily the spine and secondarily the nervous structures contained in it. A case of early prenatal diagnosis (20th week) by ultrasound of diastematomyelia with associated diplomyelia in a diabetic woman is reported. Radiological and pathological examination of the fetus after therapeutic abortion confirmed the diagnosis.

The conus medullaris: time of ascendence to normal level

This study was intended to determine the level of the conus medullaris in normal babies. We examined 114 healthy infants using high resolution ultrasound which identified the spinal cord and the tip of the conus medullaris. This method provided a good analysis of the level of the conus medullaris so that we could assess the rate of ascent to L1/2. The range of the conus level for all children was at TH12/L1 interspace to L4.78% of babies aged between the 30th and 39th postmenstrual week had the tip of the conus medullaris between L2 and L4.84% of babies aged between the 40th and 63rd postmenstrual week had their conus level between TH12/L1 and L1/2 interspace. In one girl aged 53 weeks the tip was found at L4. Ultrasound is a reliable method to observe the development of the conus level in young infants and to identify a tethered cord.

Sonographic Evaluation of the Spine in Infants and Neonates

Ultrasound is a rapid, noninvasive, cost-effective method of evaluating the spine in infants younger than six months of age. This report reviews sonographic scan procedure and normal sonographic spinal anatomy, and illustrates the sonographic appearance of occult spinal anomalies, such as meningocele, meningomyelocele, tethered cord, diastematomyelia, and sacrococcygeal teratoma.

Urodynamic evaluation of the patient with an imperforate anus: a prospective study

Prospective urodynamic evaluation of 14 patients with an imperforate anus revealed detrusor-sphincter dyssynergia in 4. Subsequent contrast voiding cystourethrograms demonstrated radiographic changes in all 4 cases, consisting of bladder trabeculation, new onset of vesicoureteral reflux or hydroureteronephrosis. Of the 4 patients 3 had a high (supralevator) imperforate anus, while 1 had a low (infralevator) lesion. Two patients had bony vertebral abnormalities and 2 had normal plain radiographs and magnetic resonance imaging of the spine. Therefore, early urodynamic study is recommended for all patients with an imperforate anus and it should complement neonatal uroradiographic evaluation. The finding of detrusor-sphincter dyssynergia should alert the urologist to the need for adjunctive management.

Occult neurovesical dysfunction in children with imperforate anus and its variants

Neurovesical dysfunction (NVD) is frequently encountered in children with imperforate anus and its variants. Such functional urologic problems are often compounded by associated anatomic urologic abnormalities that in combination may profoundly alter the course and prognosis of children with imperforate anus. Herein, we report 16 such cases. Management of NVD in children with imperforate anus offers several unique challenges that require important alterations in management. Specific recommendation are presented.

Spinal dysraphism: use of magnetic resonance imaging in evaluation

Three cases of children with spinal dysraphism are reported. Magnetic resonance imaging (MRI) was used as a primary diagnostic examination. The ages of the patients were 2 days, 4 years, and 16 years. In all instances the scan gave a precise diagnosis as well as well as an accurate delineation of the structural abnormalities before surgical treatment. Plain radiographs and ultrasound analysis may not be helpful, and invasive procedures can be associated with morbidity. Technical ease, safety, and anatomic precision suggest that MRI should be performed as a primary radiologic examination in the diagnostic workup of spinal dysraphism.

Ultrasound in the diagnosis and management of spinal and sacral tumours

Spinal and sacral tumours present not only a challenge in their initial diagnosis but also in their subsequent progress. Imaging of these tumours usually requires intrathecal contrast medium but where an acoustic window is present ultrasound may be used. The ability and clinical value of ultrasound has been assessed in 13 examinations on 10 patients. Although there was no clinical advantage in three and only equivocal advantage in one, ultrasound provided unequivocal benefit in five examinations and was synergistic in four. The technique is simple, quick and well tolerated.

Magnetic resonance imaging of dysraphic myelodysplasia. Findings in 56 children and adolescents with postrepair meningomyelocele

The spinal cord in 56 children and adolescents was examined by magnetic resonance imaging (MRI) many years after neonatal surgery on a meningomyelocele (average age 12 years). In a high percentage of cases, the diagnosis "tethered cord" was made. Associated anomalies were found with a frequency of 21%. Typical findings are presented and the impact of these results on therapy planning is discussed.

Pediatric spinal sonography. Part II: Malformations and mass lesions

The most important spinal disorders in childhood are malformations and mass lesions. The sonographic appearance of the various kinds of dysraphism and their differentiation, of malformations at the cranio-cervical junction, and of mass lesions is demonstrated and illustrated. Based on our preliminary experience, spinal sonography appears to be useful as the first imaging device for the differentiation of complex malformations and as a screening method for occult dysraphism. In mass lesions spinal sonography is useful to diagnose and follow-up disease, with additional imaging procedures currently needed for confirmation of diagnosis.

Pediatric spinal sonography. Part I: Anatomy and examination technique

Ultrasonography with high resolution technique enables the differentiation of intra- and paraspinal structures in a significant way. Conditions, examination technique, and sonographic anatomy of the os sacrum, the lumbar and dorsal spinal canal as well as the cranio-cervical junction are presented.

Anorectal malformations: evaluation of associated spinal dysraphic syndromes

The early recognition and treatment of correctable lesions of the terminal spinal cord in patients with anorectal malformations may preserve important neurologic function. Tethered cord and intraspinal masses are detectable with the use of high-resolution ultrasonography in the neonate. Fourteen infants and children with anorectal malformations and associated spinal dysraphism have been identified in our institution over the past 7 years. Six patients had cloacal exstrophy, and eight had imperforate anus (four high and four low lesions). The spinal lesions caused symptoms in only seven children; progressive neurologic deficit in five, and urinary incontinence or retention in two others. Five asymptomatic patients with cutaneous abnormalities on the back were studied and two were discovered during scoliosis evaluation. Imaging techniques included high-resolution ultrasonography, computed tomography with and without metrizamide myelography, and magnetic resonance imaging. Spinal sonography was highly accurate in the neonatal period. The application of ultrasonography can be of great advantage in early screening of patients with anorectal malformations and, in some cases, may eliminate the need for invasive imaging techniques.

Magnetic resonance imaging of postrepair-myelomeningocele--findings in 31 children and adolescents

Magnetic resonance imaging has clearly demonstrated its efficacy in the diagnosis of pathological processes in the C.N.S. We examined 31 children who had undergone plastic closure of myelomeningocele a few days post partum. We could show that a high percentage of the patients (89%) presented the pathological anatomy of a tethered spinal cord; clinical symptoms of the tethered spinal cord syndrome, i.e. progressive neurological symptoms, however, are rarely observed. Possible revision of neurosurgical treatment of MMC is discussed.

Normal development of the spinal cord in neonates and infants seen on ultrasonography

The normal development of the spinal cord from the fetal period to infancy was studied by ultrasonography (US) with a 7.5 MHz transducer. Longitudinal and transverse sections of the spinal cord were clearly observed. The sagittal and transverse diameters of the spinal cord increased with age. In order to evaluate disorders of the spinal cord precisely, it is necessary to clarify the normal features as well as the normal development of the spinal canal and cord, and the surrounding structures. US with such a high frequency transducer will be the most suitable for this purpose.

Real-time sonographic display of caudal spinal anomalies

Real-time computerized ultrasonography with 3.5 and 5.0 MHz sector and linear array transducers (Acuson) depicts spinal anatomy and pathology more clearly than was possible with previous ultrasonic equipment. Split screen (dual image) techniques display increased lengths of spine in a single image. Articulated arm, B-mode sonography remains useful for older patients in whom the pathology lies far from the transducer and in a few post-operative patients in whom dense scar frustrates real-time examination. Sonography is a very useful screening tool for subcutaneous pathology, meningoceles and lipomas, but, thus far, has failed to demonstrate consistently the presence of hydromyelia, intracanalicular (epi)dermoid tumors and dermal sinus stalks ascending toward conus medullaris.

The fetal spine

Ultrasonography has made it possible to evaluate the fetal spine in utero. Vertebral ossifications are demonstrable by ultrasonography in the early second trimester. Most spinal defects are apparent by 20-22 weeks menstrual age. Early detection of spinal anomalies allows for parental counseling and appropriate obstetrical management. Real-time equipment allows the fetal spine to be examined in parasagittal, transverse and coronal planes. The transverse plane provides the best view of the three ossification centers that form each fetal vertebra. Evaluation of the neural arch ossifications in the transverse view is crucial in detecting spina bifida defects. Ultrasonography of the fetal spine complements the use of alpha-fetoprotein levels in screening for neural tube defects. Examination of the fetal spine is also important in detecting vertebral ossification defects, particularly in cases of short-limbed dwarfs and infants of diabetic mothers.

Ultrasonic anatomy of the normal neonatal and infant spine: correlation with cryomicrotome sections and CT

High resolution computed neurosonography now displays the details of the spinal canal, subarachnoid space, spinal cord and some emerging nerve roots in axial and sagittal planes. Those familiar with this anatomy may use sonography to detect spinal pathology.

Intraoperative sonography in spinal surgery: current state of the art

Intraoperative spinal sonography (IOSS) has significant impact on the surgical management of spinal lesions. This paper describes the techniques involved, illustrates the sonographic anatomy of the spinal canal and its contents and discusses the role of IOSS in the surgical management of spinal trauma, spinal tumors, spinal stenosis and congenital anomalies.

Occult spinal dysraphism. Case report and review of the literature

This case report and review of the literature is presented to create a greater diagnostic awareness of occult spinal dysraphism. Early recognition is based upon an understanding of this congenital anomaly and its variable presentations. These most commonly include abnormal gait, various cutaneous manifestations, particularly subcutaneous lipomata, and less frequently urological complaints. Surgical intervention, to arrest disease progression, is the primary mode of treatment, and functional improvement is variable. Long-term prognosis is dependent upon severity of neurologic deficits prior to surgery and the type of lesion found intraoperatively. Familial occurrence has been reported and genetic counseling may be an important preventive measure. Recent radiologic investigations have been concerned with the use of ultrasonography in screening infants at risk.

Diagnosis of diastematomyelia with high-resolution spinal ultrasound

Two children with diastematomyelia were diagnosed before operation with high-resolution spinal ultrasonography. Neonates with evident or suspected diastematomyelia can be effectively examined by high-resolution spinal ultrasonography and spinal radiography, reserving more invasive techniques for those for whom the method proves inadequate.