3D Retinal Imaging
Retinal imaging has become an important part of long term eye health monitoring. Even in the absence of eye diseases, baseline images can provide valuable information for future examinations. Subtle variations in your optic nerve or macula can indicate very early stages of retinal disease such as glaucoma and macular degeneration.
The basis of any good ocular health examination is a careful examination with an instrument called a 'slit lamp'. A slit lamp is basically a binocular microscope that is mounted horizontally, and uses a beam of light passing through an adjustable slit in order to adjust illumination, hence the name. Using a slit lamp we are able to view your cornea, macula, optic nerve and to the far reaches of your peripheral retina.
Some eye diseases cause changes in the thickness of ocular tissue. Subtle variations can often be very important. Because a slit lamp has two eye-pieces, we can visualise the changes of thickness and depth of features in 3 dimensions. A standard retinal photograph is taken in only 2D, and 'throws away' all the useful depth information. This is where a 3D retinal image can help us by recording the precise contours of the optic nerve and macula.
Glaucoma is an eye disease where the optic nerve undergoes subtle variations in shape. A normal optic nerve has a hole in the middle of it and neural cell tissue around this hole, similar to a doughnut. The neural tissue is a collection of about 1.5 million individual nerve cell fibres in a healthy eye. Increases in the size of the hole correlate to thinning of nerve tissue (kind of like taking a bite out of the doughnut from the inside). This is readily observable in a 3D retinal image. Thinning of nerve tissues is a hall mark sign of glaucoma, and happens due to early cell death. This is usually (but not always) caused by high intraocular pressure. Without treatment to reduce eye pressure, glaucoma causes gradually worsening and irreversible peripheral vision loss.
Macular degeneration is a condition where abnormal extracellular deposits build up at the deeper layers of the macula. Over time the build up of these deposits results in chronic oxygen starvation to the macula, encouraging new abnormal blood vessel growth. These new blood vessels are leaky, and can result in fluid build-up and/or bleeding at the macula. Without treatment this will usually lead to scarring of the macula, and permanent loss of central vision. Early detection and intervention of the bleeding and swelling is crucial in order to save the macula from damage. An examination under a slit lamp with dilating drops is the best way to pick this up, although 3D retinal imaging can provide exceptionally detailed images of the macula that can be used for follow up and monitoring.
The basis of any good ocular health examination is a careful examination with an instrument called a 'slit lamp'. A slit lamp is basically a binocular microscope that is mounted horizontally, and uses a beam of light passing through an adjustable slit in order to adjust illumination, hence the name. Using a slit lamp we are able to view your cornea, macula, optic nerve and to the far reaches of your peripheral retina.
Some eye diseases cause changes in the thickness of ocular tissue. Subtle variations can often be very important. Because a slit lamp has two eye-pieces, we can visualise the changes of thickness and depth of features in 3 dimensions. A standard retinal photograph is taken in only 2D, and 'throws away' all the useful depth information. This is where a 3D retinal image can help us by recording the precise contours of the optic nerve and macula.
Glaucoma is an eye disease where the optic nerve undergoes subtle variations in shape. A normal optic nerve has a hole in the middle of it and neural cell tissue around this hole, similar to a doughnut. The neural tissue is a collection of about 1.5 million individual nerve cell fibres in a healthy eye. Increases in the size of the hole correlate to thinning of nerve tissue (kind of like taking a bite out of the doughnut from the inside). This is readily observable in a 3D retinal image. Thinning of nerve tissues is a hall mark sign of glaucoma, and happens due to early cell death. This is usually (but not always) caused by high intraocular pressure. Without treatment to reduce eye pressure, glaucoma causes gradually worsening and irreversible peripheral vision loss.
Macular degeneration is a condition where abnormal extracellular deposits build up at the deeper layers of the macula. Over time the build up of these deposits results in chronic oxygen starvation to the macula, encouraging new abnormal blood vessel growth. These new blood vessels are leaky, and can result in fluid build-up and/or bleeding at the macula. Without treatment this will usually lead to scarring of the macula, and permanent loss of central vision. Early detection and intervention of the bleeding and swelling is crucial in order to save the macula from damage. An examination under a slit lamp with dilating drops is the best way to pick this up, although 3D retinal imaging can provide exceptionally detailed images of the macula that can be used for follow up and monitoring.
