Toyama classification
Toyama proposed a new classification system of 9 categories based on three-dimensional CT or MRI information in 2004. 1)
1)
Asazuma T, Toyama Y, Maruiwa H, Fujimura Y, Hirabayashi K. Surgical strategy for cervical dumbbell tumors based on a three-dimensional classification. Spine (Phila Pa 1976). 2004 Jan 1;29(1):E10-4. doi: 10.1097/01.BRS.0000103662.13689.76. PMID: 14699292.