Dorsal intramedullary giant dermoid tumor

Intramedullary dermoid tumors are rare benign neoplasms that correspond to 1 to 2% of all intramedullary tumors, affecting specially the lumbosacral region. Those tumors are composed of remnants of embryonic tissue derived from the ectoderm, whose walls secretions cause slow growth rate. Despite its benign character, neurological injury comes from the tumor's expansive process and the collateral damage derived from the complete resection of the cyst wall, which can cause hypoesthesia and radicular pain, besides other effects as neuromuscular scoliosis. The primary treatment for intramedullary tumor is resection surgery. The case reported involves an infant with an extensive dorsal intramedullary dermoid tumor without association with spinal dysraphism, presenting clinically complete paraplegia, lower limbs atrophy, hypoesthesia from the T4 level and urinary incontinence. The physical examination revealed upper motor neuron syndrome in the lower limbs, mild cognitive delay and a significant scoliosis. Image exams showed a Cobb angle from T3 to L2 with 115º sitting and 68º with traction, besides a massive expansive intramedullary formation extending from C5 to the T9 plane. The patient underwent extensive cervical and thoracic laminotomy followed by median myelotomy and the resection of the lesion. An arthrodesis treated the secondary vertebral deformity. The postoperative period showed good surgical recovery and the control exams revealed ample resection of the lesion and adequate control of scoliosis with partial maintenance of rotational deformity