A rare coexistence of a non-dysraphic intradural lipoma and a cyst in the lumbar spine - A case report and literature review.

Introduction: Spinal intradural lipomas are rare entities, particularly when not associated with spinal dysraphism. Their diagnosis is often delayed due to their slow growth and presentation in dorsal components. Although the association between lipomas and cysts has been previously noted, the coexistence of lipomas with fluid-filled cysts is exceedingly rare. We present a case that highlights the presentation, management, and outcomes of a patient with the unusual coexistence of these two lesions in the lumbar region.

Case Report: An eight-year-old female presented to our outpatient neurology clinic with complaints of weakness and severe pain in her lower limbs, accompanied by urinary retention and lumbar focal hypertrichosis. Magnetic resonance imaging (MRI) of the spine revealed a lipoma alongside a cyst at the level of the first two lumbar vertebrae. A subtotal resection of both lesions was performed; the cyst was drained, revealing a clear fluid, while the lipoma was partially resected due to significant adhesions to the spine. The patient achieved full recovery within a few days, as confirmed by neurological and radiological evaluations.

Clinical Discussion: The origin of non-dysraphic lipomas remains unclear, with several congenital theories proposed to explain their formation. While associations with various anomalies and cysts have been documented, the coexistence of intradural fluid-filled cysts is exceptionally uncommon. This case presents several potential explanations for this phenomenon. Typically, lipomas are asymptomatic until they cause signs of cord compression. However, the presence of associated entities can lead to earlier symptom onset. Surgical intervention often involves subtotal resection due to severe tumor adhesions, which can yield satisfactory outcomes despite the presence of residual tumor postoperatively.

Conclusion: The occurrence of an intradural fluid-filled cyst in conjunction with a lipoma is rare and may represent an arachnoid cyst or a form of weakened spinal dysraphism linked to the controversial formation of lipomas. Illustrating this association is crucial, as the adhesions and indistinct boundaries between these lesions and the spinal cord complicate complete excision, necessitating subtotal resection, which appears to favor better outcomes.