Diastematomyelia with terminal lipomyelocystocele arising from one hemicord: case report

Diastematomyelia is an uncommon spinal dysraphism with midline dorsoventral clefting of the spinal cord. Formation of syrinx cavity within the hemicord, vertebral anomalies and lipomas is known to be associated with diastematomyelia. We present an unusual case of a 4-month-old girl, who presented with diastematomyelia and terminal myelocystocele, and dilatation of the terminal portion of the spinal canal with formation of a cystic structure. Findings were confirmed by subsequent surgery and histopathology. Ectopic right kidney, Chiari I malformation and changes of partial sacral agenesis were other findings noted in this case. No case report of formation of terminal myelocystocele arising from one hemicord was described in the literature we reviewed.     

Pre-surgery diagnosis of unusual presentation of diastematomyelia associated with epidermoid cysts: Diagnostic value of diffusion weighted imaging

We report a case of diastematomyelia associated with epidermoid cysts.On initial 1.5 T MRI the diagnosis of multicystic tumor or cysticercosis in the cauda equina was considered.A careful examination of the initial MRI and additional 3 T MRI raised the possibility of diastematomyelia associated with epidermoid intramedullary cysts (confirmed on diffusion weighted imaging).This information was very important for the surgeon in order to avoid an unnecessary exploration of an already compromised spinal cord.     

脊髓纵裂畸形的CT诊断

本文报告了８例脊髓纵裂畸形的ＣＴ表现，８例中骨性间隔６例，纤维性间隔１例，无间隔者１例。合并畸形有椎管内脂肪瘤１例，皮样囊肿１例，皮下脂肪瘤１例，皮下脂肪堆积１例，椎体或附近发育异常６例。ＣＴ不仅能１００％显示纵裂中的骨性间隔，而且可显示存在的合并畸形，因此它是一种很有价值的检查方法。     

Postoperative spinal ultrasonography findings in spinal dysraphia

Diastematomyelia is a form of spinal dysraphism involving sagittal clefting of the spinal cord, conus medullaris, and/or filum terminale into two hemicords. It can be an isolated finding or can be associated with meningomyelocele or meningocele. In this report, we present postoperative spinal ultrasonography findings in a patient with diastematomyelia and a tethered cord.     

Incomplete, false, and true diastematomyelia: radiological evaluation by air myelography and tomography.

Six cases of possible diastematomyelia studied by air myelography with tomography were thought to involve fibrous or bony septa, but in each case no septum was found. Surgical findings included prominent midline posterior fissures in the cord associated with fibrous bands, an unusual tentlike extension of the arachnoid over the spinal cord, and hemicords with no intervening septum. Recognition of an osseous septum on the plain film does not necessarily mean that the cord is completely divided by bone, as other structures derived from the mesoderm, such as fat or cartilage, may contribute to the septum. The importance of defining tethering of the cord posteriorly at the septum or conus level is stressed. Air myelography with appropriate projections appears to show posterior fixation of the cord to best advantage.     

Diastematomyelia — Rare and unusual features

Summary Diastematomyelia is an uncommon congenital anomaly of the spine. Four unusual variations of diastematomyelia are presented. These include (1) double diastematomyelia, (2) adult presentation, (3) diastematomyelia without a septum and unusual termination of two halves of the spinal cord, and (4) recurrence of a fibrous band following removal of an osseous septum.     

CT demonstration of complex dorsal spinal dysraphism.

An unusual case of dorsal spinal dysraphism in a four year old child is presented. Various abnormalities including diastematomyelia, an extradural arachnoid cyst arising from one of the two dural tubes, and lipomeningomyelocele with a related rib-like bony structure were demonstrated with Iohexol CT and subsequently confirmed at surgery.     

Rhombencephalosynapsis and a Chiari II malformation

Rhombencephalosynapsis is an anomaly of the hindbrain characteristically presenting with cerebellar fusion and absence of cerebellar vermis on magnetic resonance imaging. Its association with spinal anomalies has not been reported previously. We report a unique case, a 22-year-old man with cerebellar fusion associated with a cervicothoracic meningomyelocele, diastematomyelia, tethering of the spinal cord, and dorsal dermal sinuses. In addition, cerebellar tonsillar herniation and tectal beaking similar to that seen in Chiari II malformations were present. These findings suggest that rhombencephalosynapsis can be associated with spinal malformations and, furthermore, that cases with the common features of rhombencephalosynapsis and a Chiari II malformation can exist. Such an association likely represents a new anomaly of the hindbrain and spine.     

Concurrent hydromyelia and diastematomyelia

Hydromyelia was discovered in six of 13 patients with diastematomyelia. In one patient, hydromyelia affected only the segments of spinal cord above the diastematomyelia. In five patients, hydromyelia extended downward from the single cord into one or both hemicords. Because hydromyelia and diastematomyelia occur simultaneously, because they may produce very similar clinical changes, and because simultaneous or sequential surgical correction of both conditions may be necessary to achieve the best clinical result, the possibility of hydromyelia should be evaluated specifically in each patient demonstrated to have diastematomyelia.     

Demonstration of diastematomyelia and associated abnormalities with MR imaging

Three patients were studied with a 0.3 T superconducting magnet to assess the role of magnetic resonance (MR) imaging in the recognition and evaluation of diastematomyelia and associated abnormalities. Comparison was made with other imaging techniques, including metrizamide computed tomographic (CT) myelography. With MR imaging, the divided spinal cord was well imaged in its entire craniocaudal extent, comparable to CT myelography. The bony septum, when it contained a marrow cavity, was also seen well. In two patients, dural ectasia and low position of the spinal cord with and without associated lipoma were clearly imaged. MR imaging demonstrated associated syringohydromyelia in one patient that was not detected by other radiologic studies. This preliminary experience with MR imaging of diastematomyelia suggests that once the bony details of the abnormality are defined, MR imaging can delineate the presence and extent of the divided spinal cord as well as its associated abnormalities adequately, obviating other studies.     

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

Ultrasonography (US) of the spinal cord is performed in newborns with signs of spinal disease (cutaneous lesions of the back, deformities of the spinal column, neurologic disturbances, suspected spinal cord injury due to traumatic birth, and syndromes with associated spinal cord compression). The examination is performed with high-frequency linear- and curved-array transducers in the sagittal and axial planes from the craniocervical junction to the sacrum. Normal variants such as transient dilatation of the central canal and ventriculus terminalis can be demonstrated with US. US allows detection of congenital malformations, such as myelocele or myelomeningocele, spinal lipoma, dorsal dermal sinus, tight filum terminale syndrome, diastematomyelia, terminal myelocystocele, lateral meningocele, caudal regression syndrome, and hydromyelia or syringomyelia. Acquired intraspinal diseases following birth trauma and transient alterations after lumbar puncture can also be detected with US. US can demonstrate the entire spectrum of intraspinal anatomy and pathologic conditions with high geometric resolution. Therefore, US should be considered the initial imaging modality of choice for investigating the spinal cord in newborns.     

Occult diastematomyelia in adults--report of two cases

Two cases of diastematomyelia discovered in adults with minimal symptoms are described. In one case the presence of an associated thoracic neurenteric cyst supports the theory that a diastematomyelic spur represents a persistent neurenteric canal. The imaging findings are described and the incidence of diastematomyelia in adults is briefly discussed on the basis of cases previously reported in the literature.     

Diastematomyelia: prenatal ultrasonic appearances

Four cases of in-utero diastematomyelia are presented and the ultrasonic features described. Characteristic findings are localised widening of the posterior ossification centres with a central echogenic focus at the point of widening, visible on coronal scanning, and absence of a posterior defect or soft tissue mass on transverse scanning. The aetiology and management of the condition is discussed. The cases illustrate that widening of the posterior ossification centres can occur in the absence of overt spina bifida and the prenatal detection of diastematomyelia will allow for early postnatal investigation and treatment.     

3D spiral CT imaging of bone anomalies in a case of diastematomyelia.

The case of a 48-year-old woman, suffering from a diastematomyelia, is presented. This case and the diagnostic findings are used to demonstrate the demands on imaging methods with respect to a new classification of split cord malformations (SCMs) recently published. Although MRI is the method of choice for imaging of the spinal cord generally, only X-ray methods and especially conventional computer tomography provide the information necessary for correct classification of SCMs. Additional 3D-reconstructions from suitable CT-data are helpful in visualizing complex anomalies of bony structures found in most cases of SCM.     

Intraoperative sonography in spinal dysraphism and syringohydromyelia

The use of intraoperative sonography was analyzed in 24 patients with spinal dysraphism and syringohydromyelia in order to determine the role of real-time sonography in the surgical management of these patients. Specific diagnoses included tethered cord (nine), syringohydromyelia (seven), congenital tumor unassociated with a tethered cord (four), diastematomyelia (three), and occult sacral meningocele (one). Intraoperative sonography determined the exact relationship of congenital tumors to the cord before opening the dura, which allowed a more precise approach to the mass. Intraoperative sonography identified the lower end of the syrinx cavities, which allowed optimal catheter placement. Fibroglial scar tissue, which may compartmentalize these syrinx cavities, was clearly shown, and the efficacy of shunt catheter placement was immediately determined. In diastematomyelia, intraoperative sonography identified the relationship of the hemicords to bony, cartilaginous, and/or fibrous septa and demonstrated the effect on the tethered hemicords of removing these septa and constructing a single dural sac from the two dural sacs that had enclosed the hemicords. Since significant surgical decisions are based on these sonographic observations, the authors urge widespread use of intraoperative sonography in patients with spinal dysraphism and syringohydromyelia.     

Congenital spinal and cord lesions in children and computed tomographic metrizamide myelography

Summary Computed tomographic metrizamide myelography (CTMM) has developed into a highly sophisticated and accurate neuroradiologic technique in the diagnosis of childhood spinal dysrhaphic states. Of the 84 patients studied by this technique, 31 with the dysrhaphic spine also had lesions such as a tethered and low conus, diastematomyelia, or neuroenteric cysts. We believe that the exquisite pathologic anatomy obtained by CTMM obviates all neuroradiologic techniques other than a preliminary anteroposterior and lateral spinal roentgenograph.     

Gd-DTPA-enhanced MR imaging of spinal tumors

Forty-eight Gd-DTPA-enhanced MR examinations of the spine were performed in 40 patients referred for MR because of clinically suspected spinal tumor or for further evaluation of an expanded cord. The study group consisted of 32 patients with spinal tumors (seven ependymomas; seven astrocytomas; four hemangioblastomas; two arteriovenous malformations; two unidentified intramedullary neoplasms; four meningiomas; and single cases of metastatic breast carcinoma, cavernous hemangioma with associated hematomyelia, neurinoma, angiolipoma, drop metastasis from medulloblastoma, and epidermoid with diastematomyelia). In the remaining eight patients, other diagnoses were established: thoracic disk herniation (two patients), lumbosacral meningocele (one), syringomyelia secondary to arachnoiditis (four), and expanded cord secondary to gliotic tissue (one). All but two diagnoses were proved histologically by biopsy, surgery, or autopsy; in the two patients with arteriovenous malformations, the definitive diagnosis was made by spinal angiography. Contrast enhancement occurred in 30 of the 32 spinal tumors, and Gd-DTPA-enhanced T1-weighted images proved helpful in defining and outlining intra- and extramedullary spinal neoplasms. All ependymomas and astrocytomas (including low-grade astrocytomas) enhanced. In meningiomas, an immediate and uniform contrast uptake was demonstrated. Additional advantages of Gd-DTPA MR include the differentiation of solid tumor components vs syrinx or cyst or pseudotumoral areas of cord expansion, and the differentiation of residual or recurrent tumor from scar tissue in postoperative patients. Our results suggest that IV-injected Gd-DTPA improves MR sensitivity and specificity in the evaluation of spinal lesions.     

脊柱闭合不全的MR影像诊断（二）隐性脊柱闭合不全

本组隐性脊柱闭合不全包括脊髓纵裂２例、侧位脊膜膨出１例、脂肪瘤６例、终丝脂肪瘤４例、胆脂瘤５例、脊髓低位９例、肠源性囊肿１４例和骶骨发育不良２例。ＭＲ对隐性脊柱闭合不全的诊断具有较高的价值。矢状面图像可清楚地显示病变的全貌。在诊断脊髓低位和肠源性囊肿时，横断面检查十分重要。     

儿童脊髓积水空洞症在原发脊髓栓系综合征的 MRI 表现及相关分析

目的：总结儿童脊髓积水空洞症在原发脊髓栓系综合征的 MRI 表现,并与脊髓栓系综合征进行相关性分析。方法回顾性总结分析84例脊髓积水空洞症的 MRI 表现,包括脊髓积水空洞的位置、大小、形态、空洞指数等,并与引起栓系的各种病变进行统计学分析。结果脊髓积水空洞中央管呈丝状扩张15例,管状扩张21例,囊状扩张48例。脊髓积水空洞的宽度及长度与年龄均不相关。空洞指数>40%与脊髓纵裂有统计学意义(P =0.017),而与脊髓低位栓系其他各类型无相关性。脊髓低位栓系综合征中脊髓纵裂、脊膜膨出是出现脊髓积水空洞症囊状扩张的危险因素。结论脊髓纵裂和脊膜膨出更容易合并脊髓积水空洞症囊状扩张的发生,而且脊髓纵裂更容易出现大空洞指数的脊髓空洞症。     

MR imaging in the tethered spinal cord syndrome

MR examinations of the spine were reviewed in 25 patients with a clinical diagnosis of tethered spinal cord. In 21 patients (84%), the level of the tip of the conus was below the mid L2 vertebral body. The causes of the tethering were spinal lipomas (72%), tight filum terminale syndrome (12%), diastematomyelia (8%), and myelomeningocele (8%). These entities were readily identified in all instances. Bony dysraphisms were well demonstrated by MR. Interestingly, cavitary lesions/myelomalacia of the conus or the cord adjacent to the tethering lesion were seen with appropriate images in nine of 20 patients. This unexpected finding may have diagnostic and/or prognostic significance. Spinal MR was found to be extremely useful in the evaluation of the suspected tethered spinal cord. It was able to visualize the conus medullaris, assess the thickness of the filum terminale, identify traction lesions, and evaluate associated bony dysraphisms.