Retinal Imaging

Alastair Wade Optometrists offer retinal imaging at our Prudhoe, Durham and Ryton branches and are available during both Private and NHS eye examinations. Our Optometrists strongly recommend that photographs are taken during all eye examinations as they allow us to view a large image of the back of the eye and these images can be stored and compared on future visits.

Photographs are usually taken by trained optical assistants. The images produced are stored on computer and viewed on a colour monitor. Printouts can also be produced should you need to send a copy to the hospital or general practitioner. In addition, images can sometimes be used to highlight abnormalities found in front of the retinal plane: for example certain types of cataract, iris anomalies and occasionally vitreous "floaters". Because images can be retained we can compare recent photographs with those taken some time ago - this is a very effective way of detecting any changes that may have taken place.

The picture produced by the camera will generally show the optic disc and optic cup (these structures form part of the optic nerve and are associated with the 'blind spot').The macula reflex corresponds to central vision and contains mostly "cones" (the most sensitive receptors) and the peripheral retinal mostly "rods" (the least sensitive receptors').The retinal blood vessels enter the eye at the optic nerve and radiate outwards towards the macula and periphery. In some patients pigment patches (very dark areas) can be seen at the optic disc. Pigment spots can sometimes be seen in other areas of the retina - these retinal "moles" are normal but as with all moles should be monitored for changes in size and colour.

Glaucoma

The size, colour and shape of the optic disc and cup are important markers in the detection of glaucoma. Using digital imaging it is possible to record very subtle change. When this information is combined with tonometry (measurement of intraocular pressure - usually with an air puff machine) and visual field analysis we have the means to detect glaucoma in the very early stages of the disease.

Blood Vessel Integrity

The blood vessels observed on the retinal image will, in a healthy individual show certain characteristics. In the presence of certain conditions (those affecting general health as well as those specific to the eye) the vessels may become abnormal or even haemorrhage. Digital imaging enables the blood vessels to be examined in greater detail, thus improving our ability to detect any abnormality.

Photographing the Retina

A few patients (those with small pupils and certain types of cataract) will need to have drops to dilate the pupils prior to the pictures being taken. In these circumstances a separate appointment will be necessary. We do recommend that patients have both eyes photographed - even if the have a 'lazy eye'. We can still examine the image for abnormalities. Retinal photography forms and integral part of a comprehensive eye examination - we cannot therefore offer this service without performing a full eye examination. Please note that although Retinal Photography is an invaluable diagnostic aid it does not fall within the provision of NHS services.