QUIZ: No. 10, 22/03/2026

Answer: Limited dorsal myeloschisis - Non saccular type.

Limited dorsal myeloschisis (LDM) is a rare form of closed spinal dysraphism characterized by a closed midline skin defect and a persistent fibroneural stalk connecting the skin lesion to the thecal sac. There are two types.

1.       Saccular LDM: present with a skin-based (CSF) sac topped by a squamous epithelial dome

2.       Non saccular LDM: present with a skin crater covered with pearly pale epithelium “cigarette-burn mark”

Spinal cord tethering and dorsal tenting may or may not be seen. Surgical intervention can be delayed to avoid complications in the neonatal period.

The closest differential is dorsal dermal sinus, which contains an epithelium lined tract and a skin dimple.

Our case is nonsaccular type of LDM without cord tethering or tenting.