Type, frequency and earliest appearance of microvascular abnormalities (MVAs) identified after radiotherapy in years 1 and 2
| Image modality | Feature | Cumulative frequency M 18 and M 24 (N=18 eyes) | Earliest appearance (months) |
| Colour photograph | Nerve fibre infarct | 6 | 12 |
| Retinal haemorrhage | 10 | 18 | |
| Fluorescein angiogram | Microaneurysms | 7 | 24 |
| Luminal irregularities | 13 | 24 | |
| Telangiectatic vessels | 8 | 24 | |
| Perivascular capillary dropout | 15 | 24 | |
| Vascular sheathing | 10 | 24 | |
| Vascular staining | 15 | 24 | |
| Mean area of MVA involvement | 3.2±3.0 (SD) mm2 |
| |
| Optical coherence tomography | Intraretinal oedema in the area of MVA | 1* | 24 |
The area of retina involved by MVA was measured on an early fluorescein angiographic frame.
*The OCT scan lines covered the area of MVA in only one eye.