INTRODUCTION:
Limited Dorsal Myeloschisis (LDM) is a distinctive clinicopathological entity of spinal dysraphic malformations [1]. The criteria for LDM are a cutaneous abnormality and a fibro neural or fibro vascular-neural stalk that connects the base of the skin lesion to a focus on the dorsal midline of the spinal cord [1].
The pathophysiology of LDM is hypothesized to be a primary neurulation anomaly that results in incomplete disjunction between the cutaneous and neural ectoderms of the developing embryo [2]. Based on their cutaneous manifestations, LDMs are classified as saccular or non-saccular (flat) [1]. Congenital dermal sinus (CDS) is a condition of secondary neurulation, and the stalk of CDS comprises dermal elements rather than fibroglial tissue, making the distinction between CDS and LDM crucial. A CDS develops when the cutaneous ectoderm is ”pulled” to the spinal cord, whereas the fibroglial connection happens when the neural ectoderm that makes up the spinal cord is ”stretched” to the skin with an LDM.
For the diagnosis of LDM, magnetic resonance imaging (MRI) is the gold standard [3]. With visualization of the stalk connecting the skin or posterior mass to the underlying spinal cord, spinal imaging can show the characteristics of LDM [4].