Laser speckle contrast imaging detects relative blood flow reduction in traumatic optic neuropathy.

Case presentation: A 15-year-old male sustaining craniofacial injuries from a collision reported vision loss in the left eye on hospital day 12. An ophthalmologic examination revealed a visual acuity of 20/20 in the right eye and no light perception (NLP) in the left eye. Dilated fundus exam showed pink, sharp margins of the optic disc in the right eye and slight temporal pallor of the optic disc in the left eye. Imaging revealed findings consistent with impingement of the optic nerve at the level of the sphenoid fracture. The patient was diagnosed with direct, posterior traumatic optic neuropathy and started on intravenous methylprednisolone. His visual acuity was unchanged at the 6-month follow-up. Laser Speckle Contrast Imaging (LSCI) was utilized at approximately 3 weeks and 6 months following the collision. Peak Blood Flow Velocity Index (BFVi) was notably reduced in the left eye relative to the right eye at both time points. Conclusions and importance: In this case of Traumatic Optic Neuropathy (TON) following craniofacial trauma, a novel retinal-imaging modality, Laser Speckle Contrast Imaging (LSCI), was used to compare retinal blood flow dynamics between the injured and uninjured eye. After conducting a literature review in 2023 utilizing PubMed and Google Scholar using the key words (traumatic optic neuropathy, LSCI, optic nerve head, ischemia), we did not find any prior reports of LSCI application in TON to assess aberrations in blood flow dynamics. The application of LSCI technology in patients presenting with unilateral vision loss will help determine the diagnostic utility of this technology in a spectrum of disorders.