For instance, if present in a patient in whom the peripheral retina could not be visualised due to e.g. vitreous haemorrhage or poor pupil dilation or simply was visible but not readily assessable due to the presence of multiple retinal haemorrhages, it would provide strong evidence that significant peripheral RCNP was indeed present and help in deciding whether additional anti-VEGF therapy or panretinal photocoagulation was indicated. This evidence concerns the gene VEGFA and vitreous hemorrhage.