A Comparison of Hyper-Reflective Retinal Spot Counts in Optical Coherence Tomography Images from Glaucomatous and Healthy Eyes

Longitudinal imaging of vitreal hyperreflective foci in mice with acute optic nerve damage using visible-light optical coherence tomography

Hyperreflective foci (HRFs) appear in optical coherence tomography (OCT) images of the retina and vitreous of patients with various ocular diseases. HRFs are hypothesized to be immune cells that appear in response to ischemia or tissue damage. To accurately identify HRFs and establish their clinical significance, it is necessary to replicate the detection of similar patterns in vivo in a small animal model. We combined visible-light OCT with temporal speckle averaging (TSA) to visualize and track vitreal HRFs (VHRFs) densities for three days after an optic nerve crush (ONC) injury. Resulting vis-OCT images revealed that VHRF density significantly increased approximately 10-fold at 12 h after ONC and returned to baseline three days after ONC. Additional immunohistochemistry results confirmed these VHRFs as inflammatory cells induced from optic nerve damage.

Hyper-reflective vitreous spots in central retinal artery occlusion: An unusual finding in two cases

PURPOSE

To present two consecutive cases of Central Retinal Artery Occlusion (CRAO) with unusual Optical Coherence Tomography (OCT) presentation of Hyperreflective Spots (HRS) in the posterior vitreous.

CASE REPORT

The first patient was a 59 years-old male who developed CRAO in the post-operative period after aortic valve replacement. OCT scans revealed the presence of many HRS in the posterior vitreous, remarkably decreased in number at two months follow-up. The second patient was a 74-year-old male who developed CRAO after arterial chemoembolization for recurrent hepatocellular carcinoma. OCT scans showed again the presence of hyperreflective spots in the posterior vitreous and their reduction at two months follow-up with inner retinal atrophy as the final outcome in both cases.

CONCLUSIONS

HRS in the posterior vitreous have been described in inflammatory eye conditions such as uveitis, diabetic macular edema, post cataract surgery, and considered a clinical sign of inflammation. To our knowledge, the combination of CRAO and HRS has not been previously reported. The number of HRS seems to decrease over time, suggesting a role for inflammatory response in the acute stage of CRAO. A similar pathogenic process is known to occur during cerebral ischemia, where the inflammatory response may exacerbate brain injury and post-ischemic damage.