Scanning laser ophthalmoscopy (SLO) is an imaging technique that produces detailed images of the back of the eye, including the retina, optic nerve, and blood vessels. It can detect early signs of eye diseases such as glaucoma, diabetic retinopathy, and macular degeneration. SLO is sometimes used in combination with dyes to evaluate blood flow in the eye.
Scanning laser ophthalmoscopy (SLO) is an imaging technique used to examine the back of the eye. This type of eye exam produces detailed images of structures at the back of the eye, such as the retina, optic nerve, and blood vessels. During scanning laser ophthalmoscopy, a laser moves across the back of the eye and the reflected light is used to form an image. A sequence of images can be used to show changes occurring in the eye in real time, or eye scans taken at different depths can be used to create a three-dimensional image.
Because of the brightness of the laser light, scanning laser ophthalmoscopy provides clearer images of the eye than conventional photography. The laser scans the back of the eye in what’s called a raster pattern, moving from left to right and gradually moving vertically to fully map out the area. Blur is minimized by shining reflected light through a pinhole. The technique is similar to what is known as confocal laser scanning microscopy, which is used to study biological samples. Scanning laser ophthalmoscopy is slightly different because the lens of the eye takes the place of the objective lens that would be found inside a microscope.
Doctors can use scanning laser ophthalmoscopy to view the anatomy of the back of the eye in great detail, so areas of subtle damage can be detected. These may be early signs of diseases such as glaucoma, a condition in which high pressure within the eye damages the optic nerve and causes vision loss. If diagnosed early, treatment can prevent progression and save a person’s residual vision.
Scanning laser ophthalmoscopy is sometimes used in combination with two eye diagnostic procedures known as indocyanine green (ICG) and fluorescein angiography. These tests involve injecting dyes into the bloodstream. Fluorescein glows in response to light in the visible spectrum while ICG glows in infrared light.
Both fluorescein and ICG dyes are carried in the circulation to blood vessels at the back of the eye. Using scanning laser ophthalmoscopy, the time it takes for dyes to travel a specific distance through the blood vessels of the eye can be observed and measured. This allows doctors to evaluate blood flow in the retina and underlying choroid tissue, helping them diagnose eye diseases such as diabetic retinopathy or macular degeneration. In diabetic retinopathy, damaged blood vessels develop in the eyes of diabetic patients and laser surgery may be required. Macular degeneration, which is associated with aging, involves the loss of detailed vision, and there is no effective treatment for the most common form of this disease.
Protect your devices with Threat Protection by NordVPN
