Lumbar Intramedullary Epidermoid Following Repair of Sacral Myelomeningocele and Tethered Cord: A Case Report With a Review of the Relevant Literature and Operative Nuances

Abstract

Epidermoid cysts of the spine are rare tumors. While the majority of them occur spontaneously, in very few cases, they can occur following previous surgery for spinal dysraphism. Such tumors tend to occur at the site of previous surgery. The occurrence of an epidermoid cyst at a level higher than the previous surgical site is a rare entity. We present a rare case of a lumbar intramedullary and extramedullary epidermoid occurring at a level higher than the previous surgical site, along with a discussion of the causes of such an occurrence and operative nuances regarding the management of an intramedullary epidermoid in a pediatric patient.

Keywords: Epidermoid cyst; Intramedullary epidermoid; Spinal dysraphism.

Fig. 1.

Magnetic resonance imaging showing a sacral myelomeningocele in sagittal (A) and axial (B) planes. Arrow indicates level of tethered cord at first presentation.

Fig. 2.

Preoperative magnetic resonance imaging showing (A) T2 sagittal image of the whole spinal axis with a syrinx at the dorsal level and hyperintense well defined lesions at L3–5 levels. (B) Sagittal contrast image showing peripherally enhancing septate lesions with the upper lesion being intramedullary. (C) T2 axial image showing a hyperintense lesion occupying and displacing the cord to left.

Fig. 3.

Intraoperative images: (A) pultaceous cystic contents being removed (arrow), (B) cyst wall being dissected (arrow).

Fig. 4.

Histopathological examination of hematoxylin and eosin stained sections. (A) Microscopic image and (B) magnified view showing stratified squamous epithelium (white arrow) with underlying keratin flakes (black arrow) and absence of adnexal structures.

Fig. 5.

Postoperative magnetic resonance imaging showing (A) residual enhancing cyst wall within the conus and (B) comparative images of preoperative and postoperative T2 sagittal sequences showing reduced size of the residual lesion in the conus and absence of the extramedullary component.