Diabetic retinopathy-screening training program for nurses St John Eye Hospital - UNRWA

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Retinopathy terms and abbreviations
Microaneurysms (Ma’s) – Ma’s are the first lesions appearing in diabetic retinopathy.
Ma’s are physical dilations of the smallest intra-retinal blood vessels called capillaries.
These lesions appear as small circular, red dots having distinct margins and are no
larger than a blood vessel width at the disk margin. Good examples are seen in the
following standard photograph 1
Retinal Hemorrhages (H’s) – These lesions represent actual bleeding within the retina,
and either are a result of ruptured Ma’s or when the above-mentioned capillaries
become leaky enough to let blood out of the blood vessels (just as when we get a cut
on our skin). These hemorrhages can be a variety of shapes including dot, blot and
flame-shaped. They are usually larger than Ma’s (equal to or larger than a blood vessel
at the disk margin), with uneven/indistinct edges and coloring. See the below standard
photograph 2a: and concentrate on the larger red spots within the photograph.
Hard Exudates (HE’s) – These are white/yellow cholesterol deposits that usually
originate from leaking Ma’s. HE’s are irregularly shaped, vary in size, are hard edged
and often have a "fatty" appearance. HE can, and often are associated with fluid
accumulation (retinal edema) within the retina.
Soft Exudates (SE) – aka "Cotton Wool Spots" - these lesions appear as white, feathery,
fluffy or "cottony" spots. SE’s physically represent infarcts, or closures of capillaries,
within the retina; however the physical locations of these lesions are in the very
exterior layer of the retina (in the nerve fiber layer). Cotton Wool Spots often occur in
association with IRMA (discussed below).
Intraretinal Microvascular Anomalies (IRMA) – Occurring in the mid to late stages of
non-proliferative retinopathy, these appear as spidery abnormal vessels that appear
within the retina. They are typically contorted in appearance with sharp corners, often
crossing over themselves and they normally do not cross over major veins or arteries. It
is thought that IRMA physically represents either dilation of pre-existing capillaries or
actual growth of new blood vessels within the retina. Frequently occur adjacent to
CWS’s, and may be associated with other signs such as “omega” venous loops.

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IRMA - Concentrate on the center of the photograph at the small spidery blood vessels –
Early IRMA is very subtle, but this is a classic example of obvious and advanced IRMA.
Venous Beading (VB) – Also occurring in the late stages of non-proliferative disease, VB
occurs when the walls of major retinal veins loose their normal parallel alignment and
begin to appear more like a string of sausages. Physically, beading represents a
situation in which vein walls loose their elasticity and localized areas begin to dilate.
This lesion is one of the strongest predictors of progression to proliferative disease. The
above standard photograph represents this phenomenon very well.
New vessels (on the disc, NVD – or elsewhere, NVE) – aka "neovascularization"– NV
are the first of the proliferative lesions to appear. The thought is that the retina is
experiencing areas of hypoxia, or is "under-nourished". In an effort to compensate for
this problem, the eye grows new vessels in the areas lacking circulation. The new
vessels are very delicate and grow on top of the retina rather than in it, making them
prone to leaking and hemorrhaging. They can cross over one or many major retinal
blood vessels, but tend not to cross over themselves. They will often appear in a
blossom like a flower bud with the outside part of the NV more dilated than the inner
NV. They can also appear as stringy and drawn out, but this is less common.
Fibrous proliferation (on the disc, FPD - or elsewhere, FPE) - After the appearance of
NV, the eye wants to protect these new vessels and give them support and structure to
grow on. A white fibrous tissue grows either adjacent to or intertwined with the new
vessels. This FP is very "sticky" and tends to adhere to the retina and NV. These
adhesions can accidentally pull the NV and cause them to hemorrhage or can pull on
the retinal and cause it to detach.
Preretinal and vitreous hemorrhage (PRH, VH) – Occurs when the delicate NV leaks
blood or is broken by the traction of fibrous proliferations. These two lesions are
separated in name by their anatomical location. If this blood leaks into the potential
space between the retinal and the internal limiting membrane, which lines the surface
of the retina, it is called a preretinal hemorrhage. If the blood leaks into the vitreous or
the posterior chamber, it is called a vitreous hemorrhage