1. From the Department of Neurosurgery (S.D., A.S., N.S., K.P., A.A., H.B.S., S.S.P., S.G., P.S., S.M., R.C., K.K.M., M.K.T., S.N.M., V.K.K., S.K.G.), Post Graduate Institute of Medical Education & Research (PGIMER), Chandigarh, India.
2. Department of Neuroradiology (N.K., A.K., V.G.), Post Graduate Institute of Medical Education & Research (PGIMER), Chandigarh, India.