Congenital Cervical Tethered Cord in an Adult: Utility of Spinal Diffusion Tensor MR Imaging

Introduction

Tethering of the spinal cord rarely occurs in the cervical region [1]. A few case reports established trauma, previous intradural surgery, spinal cord infection and congenital abnormalities to be associated with tethering of the cervical spinal cord [2] [3] [4] [5] [6] [7] [8] [9] [10]. Spinal dysraphisms such as congenital dermal sinus tracts (DST) are often associated with spinal cord tethering but most commonly occur in the lumbosacral region [1] [2]. DST are epithelium-lined tracts that extend from the skin to the deeper neural tissue due to an incomplete separation of the cutaneous ectoderm from the underlying neuroectoderm during embryonic development [11]. In order to avoid neurological and infectious complications, early surgery including intradural exploration and complete resection of the tract has been recommended [1] [2] [3]. Usually DST and other congenital abnormalities are recognized at birth or in early childhood by typical cutaneous findings. Therefore, presentation in adulthood is extremely rare. Here, we present the case of a 30-year-old female with a progressive symptomatic cervical tethered cord due to an unusual congenital abnormality resembling a regressed DST. In patients with a tethered cord, conventional MR imaging frequently fails to detect stretch-induced pathological changes of the myelon despite the presence of spinal cord dysfunction. As recent developments in neuroimaging suggest that diffusion tensor MR imaging (DTI) may be more sensitive to detect spinal cord injuries [12] [13], we included DTI in our preoperative workup and found abnormal fiber orientation in the region of cervical cord tethering.

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