The optimal surgical procedure for patients with calcified and organized chronic 
subdural haematoma (CSDH), or "armoured brain", has not been established because 
it is difficult to obtain good re-expansion of the brain after surgery. We 
present herein the case of a 32-year-old woman with huge calcified CSDH 
manifesting as refractory headache, periods of unconsciousness, and unsteady 
gait who obtained favourable results after craniotomy. Thinning of the thick 
calcified inner membrane using high-speed air drilling was performed after 
removal of the organized CSDH. The patient obtained good re-expansion after 
surgery. This observation illustrates that it is possible to perform such a 
surgery even on a huge calcified CSDH.