OBJECTIVETo discuss the surgical treatment of chiari-I malformation complicated with syringomyelia.

METHODSThe surgical treatments of 247 cases were analyzed retrospectively. The indication of operation styles was proposed by various surgical treatment to different MRI (magnetic resonance imaging) findings. MRI findings includes: tonsillar herniation with no or slight syringomyelia (126 cases), tonsillar herniation with syringomyelia above C(2) (second cervical vertebrae) vertebral level (38 cases), serious tonsillar herniation (to C(2) approximately C(3) level) with syringomyelia of isolated spinal segments (67 cases), serious tonsillar herniation (to C(2) approximately C(3) level) with syringomyelia above C(2) vertebral level (16 cases). They were performed by posterior fossa decompression, posterior fossa decompression and incision of the syringomyelia, posterior fossa decompression and resection of the cerebellar tonsils, posterior fossa decompression and incision of the syringomyelia combined with resection of the cerebellar tonsils respectively.

RESULTSThe clinical signs and symptoms had been markedly improved or improved in 197 cases (79.8%) until patients were discharged from hospital, unchanged in 39 cases (15.8%), deteriorated in 7 cases (2.8%). there were 4 death in all cases after surgery. 107 cases were followed up from 5 months to 9 years. The postoperative MRI findings in the 107 patients demonstrated that the cavities in spinal cords disappeared completely or nearly in 78 cases, reduced in 14 cases, unchanged in 15 cases.

CONCLUSIONSPosterior fossa decompression, posterior fossa decompression and incision of the syringomyelia, posterior fossa decompression and resection of the cerebellar tonsils, posterior fossa decompression and incision of the syringomyelia combined with resection of the cerebellar tonsils should be an effective method for treatment of chiari-I malformation complicated with syringomyelia. Surgical treatment may fully ameliorate the clinical syndromes.