Ocular Toxoplasmosis Presenting With Focal Retinal Nerve Fiber Atrophy Simulating Glaucoma

Purpose: We describe a patient with ocular hypertension and nonglaucomatous retinal nerve fiber layer (RNFL) atrophy associated with an ocular toxoplasmosis retinal lesion. Patient and Method: Single case report. Results: An RNFL defect was identified adjacent to a circumscribed pigmented chorioretinal lesion superior to the macular region. The optic disc showed a prominent central cup without focal neural rim atrophy. Red-free photography and RNFL imaging using optical coherence tomography and scanning laser polarimetry showed corresponding focal RNFL atrophy. The toxoplasmosis lesion was characterized by an apparent full thickness disruption in retinal architecture, including the retinal ganglion cell layer, using spectral-domain optical coherence tomography. Conclusions: Nonglaucomatous retinal lesions may simulate glaucomatous RNFL atrophy and visual field loss, particularly when focal damage to the retinal ganglion cells occurs. Careful inspection of the retina and optic disc, with attention to the integrity of the neural rim, and analysis of the pattern of RNFL loss in proximity to a retinal lesion may enable the clinician to differentiate glaucomatous and nonglaucomatous pathogenic mechanisms.