Macular oedema is not predicted by perifoveal single blot haemorrhages

To ascertain which perifoveal changes on digital retinal screening in diabetes predict the need for subsequent macular grid or focal laser therapy.

Between 1 January 2004 and 31 December 2005, all consecutive retinal images where any lesion was within one disc diameter of the fovea were reviewed. Patients were categorized by lesion at screening as having microaneurysm, single blot haemorrhage, multiple blot haemorrhages and exudates or circinate exudates within one disc diameter of the fovea. We compared these retinal images with the findings on slit lamp examination and the related decision for laser photocoagulation.

Four hundred and twenty-four retinal images were identified. Of these, 52 were excluded, principally because of an interval between photography and clinic attendance of greater than 120 days, leaving 372 retinal images in the study group (313 patients). No patients with a single blot haemorrhage required immediate laser therapy at ophthalmology review compared with 13 (23%) of those with multiple blot haemorrhages and 36 (16%) of those with exudates or circinate lesions (P < 0.001). Thirty-nine patients with a single blot haemorrhage who did not require laser therapy underwent ongoing follow-up. None of these underwent laser therapy for maculopathy within the study time frame (9 months from initial screening event).

In this study, no patients with a single blot haemorrhage within one disc diameter of the fovea on digital retinal screening required laser treatment.