Table 7.

Tanaka’s classification (2016)

Domains	Germ layer	Dura maters	Bony structure	Anatomical location	Clinical course
Ventral endochondral (VE) group	Paraxial mesoderm	Osteal dura and dura propria	Endochondral	Cavernous sinus, sigmoid sinus, anterior condylar confluence at the level of hypoglossal canal	Benign unless there is sinus thrombosis or obstruction
Dorsal membranous (DM) group	Paraxial mesoderm	Osteal dura and dura propria	Membranous	Transverse sinus, confluence, superior sagittal sinus	Benign unless there is sinus thrombosis or obstruction
Falco-tentorial spinal (FT) group	Neural crest	Dura propria only	None (apart from the bony structure)	Olfactory groove, falx cerebri, falx cerebelli, tentorium cerebelli, spinal cord	Aggressive