Clinical and imaging findings of pattern dystrophy subtypes; Diagnostic errors and unnecessary treatment in clinical practice.

PURPOSE: To evaluate the clinical and multimodal imaging findings of various pattern dystrophy (PD) subtypes and report the initial misdiagnosis rate of PD patients resulting in unnecessary treatment in actual clinical practice.

METHODS: Retrospective, observational study. Forty eyes of 24 patients with PD were included. The distribution of PD subtypes, optical coherence tomography (OCT) and fundus autofluorescence (FAF) findings, initial misdiagnoses, revised diagnoses, duration between misdiagnosis and revised diagnosis, and unnecessary treatments administered were evaluated over this time-period.

RESULTS: Twenty-eight eyes (70%) showed adult-onset foveomacular vitelliform dystrophy, 6 eyes (15%) showed butterfly PD (BPD), 4 eyes (10%) showed reticular PD, and 2 eyes (5%) showed PD simulating fundus flavimaculatus and BPD mixed type PD. Most of the patients showed various types of hyperreflective material in the subretinal space on OCT, and hyperautofluorescence on FAF imaging. Eighteen eyes (45%) had a true PD diagnosis initially, whereas 22 (55%) of them were misdiagnosed as age-related macular degeneration, central serous chorioretinopathy, or non-specific RPE change. The mean duration between the initial and revised diagnosis was 18.7±16.8 months. In addition, 5 eyes in the misdiagnosed group underwent intravitreal anti-vascular endothelial growth factor treatment during this period.

CONCLUSION: Pattern dystrophies are a heterogeneous group of macular disorders which may mimic several macular diseases. By knowing the multimodal imaging findings, especially the distinctive FAF findings of the PDs, we may easily diagnose the disease and save our patients from unnecessary treatments.