Purpose: Placoid-pigment-epitheliopathies like Acute-Posterior-Multifocal-Placoid-Pigment Epitheliopathy (APMPPE) and Relentless-Placoid-Choroidopathy (RPC) usually show bilateral involvement. This retrospective case series describes the clinical features with unilateral disease onset. Methods: 21 patients from 9 tertiary referring institutions were collected and evaluated. Results: Seventeen patients were included: 11 (65%) had unilateral placoid-pigment-epitheliopathy consistent with APMPPE, 6 (35%) with RPC (mean age: 28.82 ± 9.1 years). Mean follow-up time was 45 ± 48 months. Forty-one percent fellow-eyes had initial inflammatory signs including vitreous-cells, vascular-sheathing, and ONH swelling. Thirty-five percent developed chorioretinal lesions during follow-up after 19.5 ± 16.9 months. Initial inflammation in fellow-eye was not associated with fellow-eye involvement (p =.5). However, subfoveal choroidal-thickness (SCT) at baseline was significantly thicker in fellow-eyes who developed chorioretinal lesion compared to fellow-eyes who did not (400 ± 70 µm versus 283 ± 127 µm,p =.047). Conclusion: Unaffected fellow-eyes may have inflammatory signs at initial disease-onset and may develop lesions over time. They should be carefully monitored, particularly if they present with an increased SCT.