Acute onset of postoperative syringohydromyelia.

Syringohydromyelia is a frequent finding in cases of tethered cord syndrome. The classical teaching is that the development and progression of a syrinx is a chronic process. We present a case report of an acute onset syringomyelia in an infant, who underwent an excision of a lumbosacral transitional lipoma and detethering of the cord. Immediately after recovery, the infant was found to have flaccid paraplegia. An emergency magnetic resonance imaging revealed a large acute onset syringomyelia for which he underwent an emergency midline myelotomy and release of fluid from the syrinx. Though the eventual recovery was good, this made us re-visit our understanding of the concept of syringohydromyelia. The case details and a plausible hypothesis for the rapid development of the syrinx are presented.