Fundus
The fundus (Latin fundus oculi ) is the inner wall of the eyeball that is visible through the transparent vitreous and contains the following anatomical structures:
- Retina (retinal)
- Optic nerve head (papilla or blind spot )
- Vessels ( arteria and vena centralis retinae )
- Yellow spot ( macula lutea )
- Periphery of the retina and transition between the retina and the ciliary body ( ora serrata )
Visualization
The view into the eye is made much easier if the pupil is dilated, possibly with medication, and allows the rear sections of the retina to be inspected as well as their middle and outer periphery by means of an ophthalmoscope . The blood vessels can be measured using retinal vascular analysis. In addition to the detection of diseases of the eye itself, internal or neurological diagnoses are possible.
Atrophy of the optic nerve can be associated with a peeled papilla and increased intracranial pressure with a so-called congestive papilla .
Photographic flash units illuminate the retina directly and intensely without the pupil being able to constrict quickly enough. In the corresponding photographic images that depict the illuminated retina, the strongly perfused retina can often be seen in the pupil as a structureless, red circle ( red-eye effect ).
Making one's own eye fundus visible
In the Autophthalmoskopie the own fundus may be observed by a bright and punctate possible in the dark light source without the ultraviolet light component (otherwise there is a risk of Photokeratitis ), such as a small light-emitting diodes - flashlight , laterally and approximately at right angles to the visual axis on the pupil is directed. The vessels of the own fundus are then visible as black shadow lines on a light background. The light source is imaged by the eye lens as a circle of confusion on the opposite side of the retina from the incidence of light and indirectly illuminates more or less the entire retina through scattering and diffuse reflection . The elevations in one's own blood vessels then cast light shadows on the retina when the light falls, which are correspondingly visible in these areas.
Individual evidence
- ↑ Jörg Braun: Tips for station work. In: Jörg Braun, Roland Preuss (Ed.): Clinic Guide Intensive Care Medicine. 9th edition. Elsevier, Urban & Fischer, Munich 2016, ISBN 978-3-437-23763-8 , pp. 1–28, here: pp. 7 f. ( Neurological examination: head and cranial nerves ).
- ↑ Carl Schweigger: Lectures on the use of the ophthalmoscope - Chapter II .: Autophthalmoskopie , Verlag Mylius, 1864
literature
- Theodor Axenfeld (founder), Hans Pau (ed.): Textbook and atlas of ophthalmology. With the collaboration of Rudolf Sachsenweger and others 12th, completely revised edition. Gustav Fischer, Stuttgart et al. 1980, ISBN 3-437-00255-4 .