Abstract
Purpose: This work assesses longitudinal microvascular changes in eyes treated with iodine-125 episcleral plaque brachytherapy (EPB). Methods: High-resolution optical coherence tomography angiograms (OCTAs) of the central 3 × 3-mm macula were obtained from iodine-125 EPB–treated and untreated fellow eyes of 61 patients. Previously validated semiautomated algorithms quantified capillary density (vessel skeleton density [VSD]) and caliber (vessel diameter index). Nonperfusion was also quantified as flow impairment region (FIR). Examinations from treated and fellow eyes obtained before treatment and at 6-month, 1-year, and 2-year intervals were compared using generalized estimating equation linear models. Dosimetry maps evaluated spatial correlation between radiation dose and microvascular metrics. Results: At 6 months, treated eyes had significantly lower VSD (0.145 ± 0.003 vs 0.155 ± 0.002; P =.009) and higher FIR (2.01 ± 0.199 vs 1.46 ± 0.104; P =.01) compared with fellow eyes. There was a significant decrease in VSD and a corresponding increase in FIR even for treated eyes without clinically identifiable retinopathy at 6 months. Vessel diameter index was significantly higher in treated eyes than in fellow eyes at 2 years (2.92 ± 0.025 vs 2.84 ± 0.018; P <.001). We categorized our cohort into low-dose (< 15 Gy) and high-dose (> 45 Gy) radiation to the fovea and noted significant differences in VSD and FIR between groups. Conclusions: OCTA can quantify and monitor EPB-induced retinopathy and can detect vascular abnormalities even without clinically observable retinopathy. OCTA may be useful in investigating treatment interventions aiming to delay EPB-induced radiation retinopathy.
Original language | English (US) |
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Pages (from-to) | 499-508 |
Number of pages | 10 |
Journal | Journal of VitreoRetinal Diseases |
Volume | 4 |
Issue number | 6 |
DOIs | |
State | Published - Nov 1 2020 |
Externally published | Yes |
Keywords
- biomarker
- capillary
- choroidal melanoma
- episcleral plaque brachytherapy
- optical coherence tomography angiography
- radiation retinopathy
ASJC Scopus subject areas
- Ophthalmology