Table 2.

Mean (±SD) percent of cochlear hair cells remaining (normalized to age-matched controls) in each region of the cochlea after neonatal DT injection

Days post-DT	Apext tip	Apex	Mid	Base	Hook
Inner hair cells
2	65 ± 11	98 ± 9	103 ± 17	90 ± 10	95 ± 5
4	15 ± 5	52 ± 24	86 ± 6	48 ± 51	14 ± 16
6	40 ± 28	16 ± 15	23 ± 16	9 ± 16	7 ± 8
10	36 ± 19	13 ± 16	17 ± 14	8 ± 14	5 ± 8
14	30 ± 9	13 ± 7	1 ± 2	0	0
21	26 ± 7	21 ± 7	12 ± 7	2 ± 3	0
Outer hair cells
2	*	*	75 ± 30	103 ± 12	101 ± 5
4	6 ± 6	5 ± 8	32 ± 19	56 ± 56	57 ± 21
6	*	29 ± 31	64 ± 19	27 ± 5	42 ± 56
10	0 ± 1	47 ± 21	71 ± 7	13 ± 11	9 ± 4
14	3 ± 5	0	0	0	0
21	7 ± 6	3 ± 3	0	0	0
Total hair cells
2	*	*	79 ± 23	100 ± 12	100 ± 5
4	8 ± 6	14 ± 3	45 ± 16	54 ± 25	47 ± 16
6	*	27 ± 26	54 ± 8	23 ± 8	34 ± 41
10	10 ± 2	39 ± 13	59 ± 3	12 ± 6	8 ± 5
14	8 ± 2	36 ± 23	0 ± 1	0	0
21	12 ± 4	7 ± 1	3 ± 2	0 ± 1	0

*Loss of hair cell integrity and organization makes it difficult to count at this time point.