1 - Department of Neuroradiology, Centro Hospitalar e Universitário de Lisboa Central, Lisbon, Portugal
- XVII Congresso da SPNR, 25 e 26 de Novembro de 2022, Lisboa
Introduction: Limited dorsal myeloschisis (LDM) is an uncommon form of spinal dysraphism, characterized by the presence of a closed focal neural tube defect and a fibroneural stalk conneting the skin lesion to the spinal cord, which is thought to result from incomplete disjunction between cutaneous and neural ectoderms. While the majority of spinal dysraphisms are diagnosed at birth or in infancy, some cases are only recognized in adulthood. The aim of this work is therefore to present the neuroimaging findings of LDM in an elderly patient.
Material and Methods: Clinical and imaging data were retrospectively obtained from the patient’s case files.
Results: A 70-year-old female with hypercholesterolemia presented with long-term low back pain radiating to the right groin. Physical examination of the patient revealed the presence of a tumefactive lumbar subcutaneous mass. A CT scan of the lumbar spine showed moderate spinal degenerative changes, as well as a heterogeneous solid-cystic subcutaneous mass connected to the spinal canal by a fibrous stalk through a posterior neural arch bone defect at the L4-L5 level. On MRI, the ventral aspect of the fibroneural stalk was connected to a low-lying conus medullaris (tethered cord). In addition, split cord malformation and a small syrinx were seen at L3-L4 and L2-L3, respectively. Taken together, the imaging features were consistent with the diagnosis of LDM. The patient underwent surgery with fibroneural stalk resection to correct the tethering effect on the spinal cord. Mild clinical improvement was achieved as the patient also exhibited spinal degenerative changes with radicular compression.
Conclusions: LDM is a distinct form of closed spinal dysraphism with specific imaging features. The presence of a fibroneural stalk connecting the spinal cord to a subcutaneous mass and additional findings (such as split cord malformation and syringomyelia) should suggest this diagnosis, even in an elderly patient.
Keywords: Limited dorsal myeloschisis; adult presentation; imaging