Ectopic midline spinal ganglion in diastematomyelia: a study of its connections.

Abstract

suMMARY The connections of an ectopic midline spinal ganglion associated with an asymptomatic sacral diastematomyelia were studied. The ganglion was intercalated in the ventral root of one hemicord and sent its efferents to the dorsal root of the other hemicord. The afferents joined the anterior root to form a midline intradural spinal nerve in the cauda equina. Islands of ectopic glia were present in both roots and the spinal nerve. Both the midline position of the ganglion and the glial heterotopias can be tentatively explained by the failure of incorporation of the dorsal cell wedge ("Zwischenstrang") into the divided neural tube.While isolated ectopic neurons are not uncommon in the spinal roots of normal subjects,' intradural ectopias of fully formed spinal ganglia are almost invariably associated with dysraphic malformations.2 An interesting variant, associated with diastematomyelia, is that in which an ectopic spinal ganglion occupies a midline position dorsal to the cleft separating the two hemicords. A case of this type was described by Gagel3 also illustrated by Ostertag4 and similar ones are recorded in subsequent publications.2 5 Little is known, however, of the connections of the ectopic ganglia or of the structure of the adjacent spinal roots. In reporting a further example of this malformation, an incidental finding in an asymptomatic adult, we describe the anatomical relationships of the ectopic ganglion and to review the pathogenesis of this lesion in light of current embryological concepts. Case reportThe patient was a 63 year old hypertensive diabetic who died ofheart failure. The 1480 gram brain was unremarkable. The spinal column showed no abnormality. The spinal cord was exposed anteriorly. The dura was single and intact. The

Split spinal cord malformations in children

“…Ganglion cells within the fibrous septum were also detected. 26,30 An immediate neurological deterioration in patients is rarely seen after surgery. 9,24,25 A microneurosurgical technique and a high-speed drill are helpful in avoiding spinal cord injury.…”

Split spinal cord malformations in children

“…[5] Blood vessels, muscle tissue, and dermoid cysts were microscopically present in the septa in other cases, as in the series reported by Pang, et al [26] Pluripotential cells of the endomesenchymal tract could develop into a variety of tissues. [26,30] An immediate neurological deterioration in patients is rarely seen after surgery. [7,32] Tibbs, et al, [33] reported five cases of midline hamartomas masquerading as myelomeningoceles or teratomas.…”

Ectopic ganglion in cauda equina: case report

“…6 Small ectopic ganglionic tissue intercalated in the ventral root of 1 hemicord has been described in an asymptomatic 63-year-old patient with sacral diastematomyelia, 9 and paramedian dorsal root ganglia have been described in an 18-monthold infant with a split cord malformation. 4 The etiology of these rare findings is thought to be associated with abnormal migration of neural crest cells during primary neurogenesis-more specifically, secondary to a premature division of the neural plate prior to closure of the neural tube.…”

“…4,9 We report a centimeter-sized, heterotopic ganglion in the filum terminale that was not associated with malformation of the spinal cord or vertebral column. This lesion mimics a neoplasm on imaging, and on clinical presentation it was initially thought to account for the patient's subjective symptoms.…”

“…5 Heterotopic dorsal root ganglion cells and ganglionic tissue have been described in patients with spinal malformations including spina bifida 6 and diastematomyelia. 4,9 We report a centimeter-sized, heterotopic ganglion in the filum terminale that was not associated with malformation of the spinal cord or vertebral column. This lesion mimics a neoplasm on imaging, and on clinical presentation it was initially thought to account for the patient's subjective symptoms.…”