diabetic maculopathy

Last edited 12/2020 and last reviewed 12/2020

This condition is more common in older, non-insulin dependent diabetics, and is the most common cause of gradual loss of vision in a patient with non-proliferative diabetic retinopathy.

• this involves
  • the breakdown of the blood–retinal barrier
  • leakage of plasma from small blood vessels in the macula
  • swelling of the central retina
  • formation of hard exudates
• diabetic macular oedema
• does not cause total blindness (1)
• leads to severe loss of central vision (1)
• most common presenting clinical symptom is blurred vision
(2)
• other symptoms can include metamorphopsia (distortion of visual image), floaters, change in contrast sensitivity, photophobia (visual intolerance to light), changes in color vision, and scotomas (localized defects of visual field)
• clinically significant macular oedema is
  • retinal thickening and/or
  • adjacent hard exudates that either involve the center of the macula

Four types of diabetic maculopathy are recognised:

• cystoid:
• characterised by microaneurysms and haemorrhages but relatively few, if any, hard exudates
• the main feature is extensive macular oedema which if persistent, may lead to a lamellar hole at the fovea with permanent impairment of visual acuity

• focal - a background diabetic retinopathy, associated with macular oedema and surrounding hard exudates

• ischaemic - similar ophthalmic picture to cystoid and differentiated from it by fluorescein angiography

• mixed - exudates, oedema and ischaemia

Reference:

1. Frank RN. Diabetic Retinopathy.N Engl J Med 2004;350:48.
2. Rittiphairoj T, Mir TA, Li T, Virgili G. Intravitreal steroids for macular edema in diabetes. Cochrane Database of Systematic Reviews 2020, Issue 11. Art. No.: CD005656. DOI: 10.1002/14651858.CD005656.pub3.