Table 1. Surgical indications to the use of IoUS.

Pathology	Experimental and clinical evidence
Dysraphism and cerebrospinal fluid disorders
Chiari malformation; diastematomyelia (split cord); tethered cord; lipomyelomeningoceles and other lipomas; syringomyelia; cystic dilatation ventriculus terminalis	Brock et al. (18), Fan et al. (19), Cui et al. (20), Cokluk et al. (21), Aschoff et al. (22), Ganau et al. (23), Zhang et al. (24)
Tumors and other space occupying lesions
Astrocytomas, ependymomas, meningiomas, schwannomas, cavernomas	Harel et al. (25), Zhou et al. (26), Shamov et al. (27), Nicácio et al. (28), Friedman et al. (29)
Functional
Cerebral palsy	Oki et al. (30), Graham et al. (31)
Trauma
Acute spinal cord injuries	Hamamoto et al. (32), Soubeyrand et al. (33), Huang et al. (34), Westergren et al. (35)
Vascular
Dural fistulas and spinal arterio-venous malformations	Prada et al. (36), Della Pepa et al. (37)
Degenerative
Rheumatoid arthritis and pseudotumors, synovial cysts, disc herniations, spinal stenosis	Chibbaro et al. (38), Alaqeel et al. (39), Ganau et al. (40), Nishimura et al. (41)
Pedicle screw instrumentation
Spinal instability	Aly et al. (42)

IoUS, intraoperatively acquired ultrasound.