Retinal examination: diagnostic procedure for examining the retina
Whether as a preventive measure, for unclear visual disorders or to clarify a known eye disease. The retina is the central sensory organ in the eye through which light is converted into images. Changes to the retina are often gradual – but can lead to permanent visual impairment if left untreated.
Modern methods such as OCT, fundus camera or Optomap now allow precise and contact-free analysis down to the finest structures. In this blog, you will find out when a retinal examination makes sense, how it is carried out, what methods are available – and what role it also plays in preparing for laser eye treatment.
What is a retinal examination – and why is it so important?
The retinal examination is one of the most important diagnostic procedures in ophthalmology. It makes it possible to detect changes to the retina at an early stage – often before symptoms appear. The retina is the part of the eye that processes incoming light and is crucial for vision. Diseases such as macular degeneration, diabetic retinal damage or vascular changes can begin there – and progress unnoticed.
What happens during a retinal examination by an ophthalmologist?
The exact procedure and the choice of examination method depend on whether it is a preventive measure, a follow-up check or the specific diagnosis of a retinal disease.
Retinoscopy with eye drops – the classic method
In classic retinoscopy (ophthalmoscopy), the pupil is dilated using eye drops so that the ophthalmologist can assess the entire back of the eye using a magnifying glass and light source. This allows the optic disc, macula, vessels and peripheral areas of the retina to be inspected in detail.
This method is proven, safe and frequently used for routine examinations and for the early detection of retinal diseases.
Visual acuity is temporarily impaired after administration of the drops – driving is therefore not permitted.
Retinal examination with contact glass – precise insights
A special contact lens is used for certain issues – such as suspected retinal detachment, vascular changes or tumors. It is placed directly on the anaesthetized eye and allows a three-dimensional and highly precise assessment of the retina, especially its outer areas.
This examination is particularly helpful in cases of severe short-sightedness, changes in the peripheral area of the retina orto check the progression of known diseases. It is not painful, but is somewhat more intensive than a simple endoscopy.
Digital retinal examination with fundus camera or Optomap
Modern devices such as the fundus camera or the Optomap system enable contact-free, high-resolution imaging of the retina – often without dilating the pupil. This produces digital images that can be saved and compared with previous images if required.
This non-invasive examination is ideal for screening, documentation and follow-up. It is a central component of modern diagnostics, particularly for chronic retinal diseases such as AMD or diabetic retinopathy.
Modern imaging techniques for analyzing the retina
In addition to classic retinoscopy, there are numerous imaging procedures available today that enable a detailed representation of the retinal structures – often non-contact and digital. They are particularly important for the early detection, follow-up and documentation of changes in the retina, especially in the macula, optic disc or blood vessels.
OCT – Optical coherence tomography at a glance
OCT (optical coherence tomography) is a state-of-the-art, non-invasive procedure that uses light waves to produce cross-sectional images of the retina. This allows even the most subtle changes in the retina and macula to be detected – often at the earliest stage of a disease.
It is standard in the diagnosis of:
- AMD (age-related macular degeneration)
- Macular edema
- Glaucoma
- diabetic retinal changes
The examination is quick, painless and possible without pupil dilation.
Fluorescence angiography for vascular imaging in the retina
In fluorescein angiography, a dye is injected into the arm vein, which is distributed through the blood vessels of the retina. Special cameras then record how the dye is distributedin the fine retinal vessels. In this way, vascular constrictions, leaks or occlusions can be precisely detected.
It is particularly helpful for:
- diabetic retinopathy
- Vascular diseases
- Macular changes with fluid accumulation
The method is tried and tested, but somewhat more complex and is used specifically for suspected vascular changes.
Laser-based diagnostic procedures – precise and contactless
Modern laser-based procedures, such as the scanning laser ophthalmoscope (SLO), enable non-contact and high-resolution imaging of the retina, often even in suboptimal lighting conditions or without dilating the pupil. By using special laser light wavelengths, even deeper structures can be visualized.
This technique is primarily used in specialized eye clinics or for the early diagnosis of retinal changes and offers maximum precision with minimal stress for the patient.
What role do examinations of the retina play in laser eye surgery?
If laser eye treatment is planned – for example to correct short-sightedness, long-sightedness or astigmatism – an examination of the retina is an essential part of the preliminary examination. This is because even if laser treatment is performed on the cornea, it must first be ensured that the retina is free of pathological changes.
Why this is so important:
- Severe short-sightedness increases the risk of retinal changes or detachment
- Fine cracks, holes or degenerative zones must be identified before the procedure and, if necessary, stabilized in advance with the laser
- Retinal diseases such as maculopathies or vascular changes can have an influence on the expected visual acuity after laser treatment
Depending on the individual findings, the ophthalmologist will therefore carry out one or more retinal examinations (e.g. OCT, fundus camera or contact lens examination) in order to be able to make an informed decision on suitability for laser eye surgery.
