Table 3.

Neurological worsening at discharge and at follow-up according to the type of the procedure (IONM following alerts vs. non IONM).

	Patients	Major alert	Neurological worsening at discharge	Neurological worsening at follow-up
IONM-assisted procedure	162	21	8 - 3 (with both mMEPs and D-waves) - 5 Meningiomas (2 cervical, 1 thoracic, 2 lumbar) - 2 Schwannomas (1 thoracic, 1 lumbar) - 1 Ependymoma (lumbar)	5 (all of them had no D-waves recording) - 3 Meningiomas (1 thoracic, 2 lumbar) - 1 Schwannoma (lumbar) - 1 Ependymoma (lumbar)
Non IONM-assisted procedure	87	N.A.	18 - 7 Meningiomas (4 thoracic, 3 lumbar) - 7 Schwannomas (3 cervical, 4 lumbar) - 4 Ependymoma (4 lumbar)	10 - 4 Meningiomas (3 thoracic, 1 lumbar) - 3 Schwannomas (3 cervical) - 3 Ependymoma (3 lumbar)