Spinal intramedullary dermoid cyst associated with filar lipoma: A case report and literature review

Background: Several authors have reported the various patterns of coexistence of spinal dermoid cysts and lipoma; however, the association of intramedullary dermoid cysts with lipoma is extremely rare. In addition to the embryological and pathological aspects of this rare condition, we discuss the feasibility of combined microscopic and endoscopic procedures for the management of intramedullary dermoid cysts. Case description: An 18-year-old woman presented with right buttock pain. Magnetic resonance (MR) imaging revealed a large, well-defined mass extending from L2 to L4. The conus medullaris terminated in the mass and was tethered by a fatty filum. According to the signal intensities on MR images, the mass could be divided into two components. The upper component existed intramedullary and was iso- to hypo-intense relative to the spinal cord on T1-weighted images. The lower component exhibited homogeneous hyper-intensity signals on both T1- and T2-weighted images. Partial removal of the cyst wall and evacuation of the cyst contents followed by untethering of the spinal cord were performed by the combined microscopic and endoscopic procedures. The patient's symptoms were relieved postoperatively and pathological studies confirmed the diagnosis of dermoid cysts associated with lipoma. Conclusions: We present a rare case of an embryological “collision” of an intramedullary dermoid cyst associated with filar lipoma underlining the spectrum of intradural pathologies in spinal dysraphism. Surgical management is creative in these circumstances and multimodal. Our surgical management shows that the use of endoscopes can be effective in the surgical removal of long sectional spinal dermoid cysts. Keywords: Endoscope, Fatty filum, Filar lipoma, Intramedullary dermoid cyst, Tethered cord