Central atlantoaxial instability as a cause of syringomyelia mimic intramedullary lipoma

Abstract

A case of a 32-year-old male patient is reported. He was admitted with complaints of burning dysesthesias over his right upper limb and chest and spasticity in the legs. Investigations revealed a long segment intramedullary tumor, image intensity of which matched lipoma. Imaging of craniovertebral junction suggested atlantoaxial “facetal” instability. Atlantoaxial fixation was done, and the intramedullary lipoma was not physically handled or manipulated during surgery. The patient improved in his neurological condition following surgery. The follow-up imaging showed that the intramedullary lipoma reduced significantly in its dimensions. From the case, it appears that the presence of “fat” and “water” in the intramedullary location might have similar pathogenesis.

Fatty syringomyelia mimicking lipoma with spinal cord pilocytic astrocytoma

“…There was only one report by Atul Goel et al 4 in 2020 suggesting lipoma-like syringomyelia fading after treatment of instability without any intervention to syringomyelia. 4 They described that "the reduction of lipoma on delayed postoperative imaging," similar to the reduction in the syringomyelia cavity, was a surprising observation. 4 Multiple types are described for spinal cord lipoma from complete intraspinal to lipomyelomeningocele 3 and fatty filum terminale 6 according to the embryonic background of spinal lipoma.…”

“…4 They described that "the reduction of lipoma on delayed postoperative imaging," similar to the reduction in the syringomyelia cavity, was a surprising observation. 4 Multiple types are described for spinal cord lipoma from complete intraspinal to lipomyelomeningocele 3 and fatty filum terminale 6 according to the embryonic background of spinal lipoma. It is nearly impossible to have a circumscribed lipoma in a fused spinal cord, and spinal cord lipoma almost always has to be associated with an open, unfused, and tethered cord.…”

“…Until now, according to our literature review, there is no reported case of a similar case as an association of spinal cord neoplasm and fat-containing syringomyelia mimicking lipoma. There was only one report by Atul Goel et al 4 in 2020 suggesting lipoma-like syringomyelia fading after treatment of instability without any intervention to syringomyelia. 4 They described that "the reduction of lipoma on delayed postoperative imaging," similar to the reduction in the syringomyelia cavity, was a surprising observation.…”

Intramedullary lipoma mimicking syringomyelia: a case report and literature review

“…There are syringomyelia cases mimicking intramedullary lipoma 7,8 and an intramedullary lipoma case combined with syringomyelia 9 (Table 1). In patients with intramedullary tumors, syringomyelia can occur either above or below the tumor.…”

“…Therefore, non-spinal dysraphism intramedullary lipoma and syringomyelia can both be secondary to other spinal tumors and can occur simultaneously. Some scholars have pointed out that the excess uid, fat tissue, and even bone tissue in the spinal cord may be related to the instability of the spinal cord, which is the self-protection of the spinal cord 7 , but its mechanism needs further study.…”