Title

ACUTE PARACENTRAL SCOTOMA FOLLOWING STRENUOUS PHYSICAL ACTIVITY

Summary

A 33-year-old male patient presented to the retina department with a history of paracentral scotoma in his left eye, immediately after strenuous physical activity 10 days prior. The patient had no ocular complaints before the sudden and painless appearance of an inferonasal scotoma following a Crossfit session. He had no prior ocular or medical history, except the use of topical Minoxidil for hair loss. Uncorrected visual acuity was 20/20 OU. Biomicroscopy did not reveal any abnormal findings. Amsler grid testing showed a well-defined paracentral inferonasal scotoma in the left eye. On funduscopic examination, a reddish-brown petaloid lesion was barely evident superotemporally to the fovea. The lesion was more evident on near infrared reflectance imaging, as a hyporeflective well-defined lesion at the same location. Fundus autofluorescence did not reveal any changes. SD-OCT of the corresponding region showed a hyperflefective plaque involving the outer plexiform and outer nuclear layers, with disruption of the underlying external limiting membrane, ellipsoid and interdigitation zones. Fluorescein angiography revealed a dilated arteriolar branch adjacent to the affected area, with no evident abnormalities at the lesion’s site. The right eye had no remarkable findings. Taken together, these findings suggest a diagnosis of Acute Macular Neuroretinopathy (AMN) in the left eye. AMN is a rare disease with no clear etiology, that has been associated with a number of distinct possible causal factors, such as a myriad of different drugs, caffeine, trauma, acute changes in blood pressure and systemic diseases. Recently, OCT angiography has been used to show microvascular changes in the deep vascular retinal plexus in cases of AMN. It is possible that, in this case, the strenuous exercise led to vascular changes that resulted in reduced blood flow to the deep vascular plexus in the affected region, causing the retinal lesion.

Area

CLINICAL CASE

Authors

Tomás Teixeira-Pinto, Leandro Jerez Chaves, Amanda Schnorr, Rodrigo Jorge