White spot lesions in vitreoretinal lymphoma: multimodal imaging features and differential diagnosis.

AIMS: To characterise the clinical and multimodal imaging (MMI) features of vitreoretinal lymphoma (VRL) with white spot lesions (WSLs) and differentiate it from multiple evanescent white dot syndrome (MEWDS). METHODS: This retrospective observational case-control study consecutively enrolled patients with biopsy-proven VRL between 2018 and 2024 at Fudan University Eye and ENT Hospital. Included patients with VRL with baseline WSLs on fundus photography comprised the WSLs VRL group compared with 34 eyes from 34 patients diagnosed with primary MEWDS in 2024. RESULTS: Totally 35 (35/158, 22%) eyes of 25 (25/89, 28%) patients (53.8 (SD 10.4) years; 80% female) presenting with WSLs were included in the WSLs VRL group. Eyes with WSLs presented with significantly shorter symptom duration and better visual acuity at initial examination than those without WSLs (both p<0.001). Compared with the MEWDS cohort, the WSLs in VRL demonstrated a distinct eccentric, peripheral and limited distribution, involving <50% retina in significantly more eyes than in MEWDS (p<0.001). Involvement of the posterior pole and macula was significantly less frequent in VRL (both p<0.001). The coexistence of multiple fundus autofluorescence patterns was more common in VRL (p<0.001), and a distinctive pattern of hypoautofluorescent spots with hyperautofluorescent rings was observed in 23 of 35 VRL eyes but was absent in MEWDS. Optical coherence tomography revealed more frequent retinal pigment epithelium abnormalities in VRL (p<0.001). CONCLUSIONS: WSLs emerged as a potential early sign of VRL, demonstrating distinct MMI features. Recognising these features aids early diagnosis and differentiation from mimickers like MEWDS.