Table 1.

Comparative cochlear anatomy and published electrode insertion distances

Species	Length of scala tympani (mm)	Cross sectional area of scala tympani in basal turn (mm2)	Volume of scala tympani (µl)	Published electrode insertion depths (mm)
Rat	7.2a	0.1 a	1.0 a	2–3d
Guinea pig	16.2 a	0.4 a	4.8 a	2–4.5e
Cat	22c	2.0 b	N/A	4–8f
Human	28.5 a	2.2 a; 2.0 b	29.2 a	<25g

^a(Salt 2010)

^b(Hatsushika et al. 1990)

^c(Igarashi et al. 1968)

^d(Hsu et al. 2001; Shepherd et al. 2004)

^e(Hartshorn et al. 1991; Miller et al. 1995; Shepherd et al. 2005)

^f(Coco et al. 2007; Fallon et al. 2009a; Hartmann et al. 1997; Kral et al. 2002; Leake et al. 1991; Leake et al. 2000; Ryugo et al. 2010; Shepherd, Clark, and Black 1983; Xu et al. 1997)

^g(Clark et al. 1983; Hochmair-Desoyer and Hochmair 1980; Rebscher et al. 2008)