Ontology highlight
ABSTRACT: Purpose
Traumatic optic neuropathy (TON) is the most feared visual consequence of head and ocular trauma in both military and civilian communities, for which standard treatment does not exist. Animal models are critical for the development of novel TON therapies as well as the understanding of TON pathophysiology. However, the models currently used for TON have some limitations regarding consistency and mirroring the exact pathological progression of TON in closed ocular trauma. In this study, we modified the model of controlled cortical impact and adapted it for studying TON.Methods
We defined new standardized procedures to induce TON in mice, wherein the optic nerve is reproducibly exposed to a graded controlled impact of known velocity to produce a graded deficit in retinal ganglion cell (RGC) electrophysiological functions.Results
The key results of validating this newly modified model, "controlled orbital impact (COI)," included (1) the injury parameters (velocity as well as contusion depth and time), which were quantifiable and manageable to generate a wide range of TON severities; (2) a reproducible endpoint of diminished positive scotopic threshold response (pSTR) has been achieved without the interference of surgical variability and destruction of surrounding tissues; (3) the contralateral eyes showed no significant difference to the eyes of naïve mice, allowing them to be used as an internal control to minimize interindividual variability among mice; and (4) the occurrence of injury-associated mortality and/or ocular comorbidity was rare.Conclusions
Taken together, this model overcomes some limitations of prior TON mouse models and provides an innovative platform to identify therapeutic targets for neuroprotection and/or neurorestoration following traumatic ocular injury.
SUBMITTER: Ibrahim AS
PROVIDER: S-EPMC6262644 | biostudies-literature | 2018 Nov
REPOSITORIES: biostudies-literature
Ibrahim Ahmed S AS Elmasry Khaled K Wan Ming M Abdulmoneim Samer S Still Amber A Khan Farid F Khalil Abraham A Saul Alan A Hoda Md Nasrul MN Al-Shabrawey Mohamed M
Investigative ophthalmology & visual science 20181101 13
<h4>Purpose</h4>Traumatic optic neuropathy (TON) is the most feared visual consequence of head and ocular trauma in both military and civilian communities, for which standard treatment does not exist. Animal models are critical for the development of novel TON therapies as well as the understanding of TON pathophysiology. However, the models currently used for TON have some limitations regarding consistency and mirroring the exact pathological progression of TON in closed ocular trauma. In this ...[more]