Assessment of the Potential for Introducing Bilateral Injury Using the TITON Apparatus

Abstract

 

Purpose

 

Traumatic optic neuropathy (TON) occurs in up to 5% of all head traumas resulting in severe visual deficit or blindness. In this study bilateral torsional indirect TON was induced in a physiologically relevant rat model, which may be used for development of novel therapeutics.

 

Methods

 

A torsional indirect TON insult was applied to both eyes using the TITON apparatus (Asemota, B. I. et al., ARVO 2014 E-abstract 55:6194). Flash visual evoked potentials (fVEPs) were used before and after injury to assess the performance of the retinal ganglia and optic nerves. The amplitude and velocity of the insults were varied to modulate the bilateral symmetry of TON. H₀: The changes in fVEPs were different between eyes in the same animal.

 

Results

 

The TITON apparatus was capable of inducing bilateral TON. Modulation of the parametric values of the insults resulted in the presentation of bilaterally symmetrical TON. P-values for H₀: P1-N1 amplitude = 0.668625, P1-N1 latency = 0.516895, P2-N2 amplitude = 0.964479, P2-N2 latency = 0.725215.

 

Conclusions

 

The TITON apparatus is capable of inducing bilaterally symmetrical TON. Further modulation of the parametric values resulted in bilaterally non-symmetrical TON. These findings suggest that the model can be used in the study and development of neuroprotectives for the optic nerve and retinal ganglion cells. Controlled production of bilaterally non-symmetric TON may prove highly valuable for future research involving the replication of medically observed TON for more specialized treatment purposes.  

 

Figure 1: Data acquisition from an fVEP waveform showing P1, N1, P2, N2. Latency and Amplitude were determined for both P1-N1 and P2-N2.