Optic nerves of animals treated with asymmetric charge-balanced (ACB) 1:4 waveforms for 6 weeks.

<p>(A-I) Orthogonal images (20x magnification) of cholera toxin B-labeled optic nerves of animals in the ACB 1:4 waveform group. Many axons seen past the crush site (asterisk). (A1-I3) Select Z-stack images were collapsed and magnified from corresponding insets in (A-H) to reduce background noise and show the course of retinal ganglion cell (RGC) axons more clearly. Scale bars, 250 <i>μ</i>m. (J) Schematic of ACB 1:4 waveform. (K) Quantification of RGC axon density at 250 <i>μ</i>m intervals from the crush site after stimulation with various waveforms for 6 weeks (UnTx, N = 5; SCB 1:1, N = 4; ACB 1:4, N = 6; ACB 4:1, N = 4; error bars, SEM; * p < 0.05, ** p < 0.01, *** p < 0.001; two-way ANOVA with Tukey’s multiple comparisons test).</p> <p>(DOCX)</p>