How is the optic nerve examined?
During the examination of the optic nerve, the visual acuity, the field of vision and the fundus of the eye are usually checked. Visual acuity can be checked using standardized charts. These must be read from a distance of five meters, with the font size decreasing with each new line.
The visual acuity can then be calculated from the line and distance that the patient can just read. An optic nerve examination usually refers to a so-called fundoscopy or ophthalmoscopy. This examination is also called ophthalmoscopy or ophthalmoscopy of the back of the eye.
In this procedure, special eye drops are first administered to dilate the pupil so that the examining doctor can perform a complete examination. Then the doctor uses a special device close to the eye, using a system of magnifying glass and light source, to look at the papilla, i.e. the orifice of the optic nerve at the eye, and determine any damage. Some patients find this examination somewhat unpleasant, but it is usually not painful.
Other diagnostic options in which the optic nerve is (co)examined include computer tomography (CT) or magnetic resonance imaging (MRI). In these cases, the thickness of the optic nerve and the presence of possible injuries can be checked in particular. However, due to radiation exposure and costs, these procedures are not part of a normal optic nerve examination.
The orifice of the optic nerve in the eye, i.e. the papilla, can, for example, be examined by means of optical coherence tomography (abbreviated OCT). This is an imaging examination in which the retina (retina) is shown together with the papilla. At the end, the doctor receives an image of the retina with its various layers and the part of the retina where the optic nerve enters.
Here, the diameter can be determined and, depending on the location and extent, possible damage can be diagnosed. The OCT examination is performed using a special device and can be compared to a photo without flash. The whole procedure takes only a few minutes and is not associated with pain. The OCT examination is usually not covered by the public health insurance.
