Ophthalmoscopy (synonyms: funduscopy, ophthalmoscopy, ophthalmoscopy) is used to inspect the fundus of the eye and to detect any pathological (diseased) changes in the coroid (choroid), retina (retina), and optic nerve (optic nerve). The procedure dates back to Helmholtz, the inventor of the ophthalmoscope, in 1850. Today, modern ophthalmoscopes enable comprehensive and indispensable diagnostics in ophthalmology.
Indications (areas of application)
- Any deterioration of vision
- The prophylactic examination of patients with, for example, diabetes mellitus or hypertension (high blood pressure).
The procedure
In ophthalmoscopy, two different variants must be distinguished: direct ophthalmoscopy and indirect ophthalmoscopy.
In the following, the procedure of direct ophthalmoscopy is presented first: The examining physician sits directly in front of the patient. The ophthalmoscope has an electric light source that shines through a small mirror into the patient’s eye through the pupil onto the retina. The patient is instructed to fixate a reference point in the distance with the other eye while the doctor positions the ophthalmoscope as close to the eye as possible. The doctor perceives the light or image reflected from the patient’s retina, magnified approximately 16 times, as an upright, real image. This allows him to assess, for example, the optic disc (exit site of the optic nerve) and the macula (yellow spot – site of the sharpest vision on the retina). Any refractive errors (defective vision such as farsightedness or nearsightedness) in both the doctor’s eye and the patient’s eye are corrected by built-in lenses.
In indirect ophthalmoscopy, the doctor is at a greater distance from the patient (about 60 cm). With his outstretched hand, he holds a converging lens with a refractive power of approx. 20 dpt at a distance of 10-15 cm in front of the patient’s eye. The doctor’s hand rests on the patient’s forehead. The patient is now instructed to fixate a reference point behind the doctor while the doctor looks at the 2-6 times magnified, inverted virtual image produced by the converging lens. Both forms of ophthalmoscopy are easier in a darkened room.
To facilitate ophthalmoscopy, a mydriatic (sympathomimetic, parasympatholytic – drug that dilates the pupil) can be used, it should be noted that the patient is not able to drive after the examination due to accommodation disorders.
The following changes can be detected by ophthalmoscopy:
- Damage to the optic nerve
- Damage to the blood vessels supplying the retina – e.g., as a result of diabetes mellitus, hypertension (high blood pressure), etc.
- Changes in the macula lutea (place of sharpest vision) – exclusion of macular degeneration.
- Changes in the retina – for example, an Ablatio retinae (Amotio retinae, retinal detachment), which can occur degeneratively and by tumors or injuries.
- Inflammation in the eye – for example, retinitis (retinitis).
- Tumors in the eye
Ophthalmoscopy is a standard diagnostic procedure in ophthalmology (eye care) and, as a noninvasive procedure, provides valuable information about the condition of the back of the eye.
