Neurenteric cyst of the conus medullaris.

Background: Neurenteric cysts (NECs) are rare developmental malformations of the central nervous system (CNS) which originate as benign congenital lesions. They originate from developmental foregut precursors, and are presumed to be the result of abnormal partitioning of the embryonic notochord plate. Such NECs predominantly arise in the cervical region in patients around 6 years of age or in their twenties or thirties. Notably, NECs of the conus medullaris are exceedingly rare, especially in patients of advanced age.

Case Description: A 70-year-old male presented with bilateral upper thigh and leg pain of over 20 years duration. His pain worsened over the past 3 years, and he sought surgical management. Although his neurological exam was normal, the lumbar magnetic resonance imaging revealed an intradural, nonenhancing, thin-walled, cystic lesion at L1/conus medullaris. The lesion was successfully resected without any adverse sequelae.

Conclusions: NECs are rare congenital legions that involve the spine. Here, an L1 intradural extramedullay neuroenteric cyst of the conus medullaris was resected without complications.