Three days after the August solar eclipse, a young woman presented to New York Eye and Ear Infirmary of Mount Sinai in New York City with classic symptoms of solar retinopathy, which is a rare form of retinal damage caused by direct sungazing. She also had a persistent blind spot in her dominant left eye.
Upon examination, she reported having viewed the eclipse with both eyes open when peak obscuration of solar area by the moon was about 70%. She looked at the solar rim several times for approximately 6 seconds without protective eyewear, and then again for approximately 15 to 20 seconds using eclipse glasses from an unknown manufacturer.
About 4 hours later, she noticed blurred vision, metamorphopsia (distorted vision with lines appearing wavy or broken and with flat surface bend), and color distortion, all worse in her left eye, and a central black spot in the left eye.
“When severe, solar retinopathy can cause an absolute scotoma [blind spot],” write Chris Y. Wu, MD, from the Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, and colleagues, in their report, published online December 7 in JAMA Ophthalmology.
Retinal Lesion Mirrored Shape of the Eclipsed Sun
Funduscopy was normal in the right eye and showed a yellow-white spot in the left fovea. Both eyes had normal results on optical coherence tomography (OCT) angiography, but spectral-domain OCT showed acute solar retinopathy, which was mild on the right and severe in the dominant left eye.
Adaptive optics scanning light ophthalmoscopy also showed more severe damage, suggesting definitive photoreceptor cell death, in the left eye. This had a large area of abnormal and non–wave-guiding photoreceptors, compared with a small region of non–wave-guiding photoreceptors in the right eye.
Visual acuity was 20/20 in the right eye and 20/25 in the left eye. Microperimetry showed a notched, ring-shaped, absolute central scotoma in the left eye, with paracentral decreased retinal sensitivity, but was normal in the right eye.
The shape of the scotoma drawn by the patient on an Amsler grid mirrored the shape of the lesion on adaptive optics and on en face OCT of the left eye. These showed a hyperreflective lesion that intensified in area from the inner to the middle retina and became mostly hyporeflective in the outer retina. In the right eye, there was a small circular hyperreflective area, with central hyporeflectivity in the outer retina.
This crescent-shaped lesion appeared to be reflections of the solar rim as the patient viewed it during the eclipse and as it caused light damage to her retina. The corresponding central scotoma persisted for 6 weeks after the eclipse.
The absence of a scotoma in the right eye corresponding to the lesion seen on adaptive optics might be explained by the small size of the lesion, its presence in the nondominant eye, or its chronicity from an unrelated cause.
Certified Eclipse-Viewing Glasses Needed for Sungazing
“During a partial solar eclipse, when part of the sun’s core remains visible, viewing the solar rim without eclipse-viewing glasses with special-purpose solar filters can lead to severe solar retinopathy with an absolute central scotoma,” the authors conclude. “Young adults, whether owing to clearer optical media, larger pupils, or poorer recognition of the dangers of viewing the eclipse with improper protective eyewear, may be especially susceptible.”
Solar retinopathy may result from photochemical toxicity generated by excess short-wavelength visible light and thermal injury from near-infrared radiation, primarily affecting the foveal photoreceptor outer segments and retinal pigment epithelium.
There was no external source of funding. The authors have disclosed no relevant financial relationships.
JAMA Ophthalmol. Published online December 7, 2017. Full text
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