[Dorsal extradural hourglass lipoma in children].

The authors would like to recount and discuss the case of a 14 months old child which presented a dumbbell dorsal lipoma, purely extradural with no congenital anomalies. The warning signal was the discovery of paraparesis with the regression of walking ability. The hypothesis of medullary compression by a dumbbell dorsal tumor was quickly dismissed with the discovery of a mediastinal mass on the pulmonary X-Ray. A diagnosis of the pre-operational neuroblastoma was carried out because of detection of dorsal epidural medullary compression revealed by the myelography. The testing was completed with a vertebral computed tomography, which clearly showed the extent of medullar compression, and the mediastinal tumoral development under the paravertebral muscular masses. The child was operated on at 2 fronts, vertebrally and thoraxically for an encapsulated, perfectly separable and non hemorrhaging tumor. The anatomopathological examination confirmed the diagnosis of the lipoma. It is in the resumption of the computed tomographic examination that the tumoral density measures will confirm fatty tissue with numbers of density--50. In light of the literature, we are discussing the appearance of the lipoma, entirely exceptional because of its dorsal location, its extradural and certainly its dumbbell position, with large thoraxic development. It is necessary to stress the importance of the meticulous neurological examination of the child, the diagnostical necessity of the CT scan and the importance of the avoidance of the creation of an instable vertebral lesion at the time of laminotomy. In this case only the early double surgical operation permitted the recovery of the child.