Standard Examinations
1. Examination of visual acuity
First, your eyes are examined with the autorefractometer. The autorefractometer measures the approximate diopters of your eyes before the doctor fine-tunes the measurement.
The exact, doctor’s determination of the visual acuity is done with fitting glasses. You will be asked to read out numbers or letters that are presented to you on a screen and are also held out at reading distance. One eye is covered at a time and the required prescription is placed in front of the eye. At the end, the visual acuity of both eyes is determined together.
If you wear contact lenses, the exact prescription can only be determined after you have been off contact lenses for 3 days.
2. Determination of the strength of the glasses
The strength of the glasses you bring with you can be measured on the lensometer.
3. Slit lamp examination of the “anterior segment” of the eye
The slit lamp is the ophthalmologist’s examination device. The slit lamp is used to examine the eyelids, tear ducts, conjunctiva, cornea, iris, lens and aqueous humor with high magnification.
4. Eye pressure measurement
Eye pressure measurement is performed in my office by means of “applanation tonometry”. For this purpose, local anesthetic eye drops are used to make the eyes insensitive to touch. Afterwards, the eye pressure is measured with a small device on the slit lamp. Eye pressure measurement is a standard examination for patients over 40 years of age.
5. Tear fluid examination (tear break-up time)
The tear break-up time is examined at the slit lamp after the eyes have been made insensitive to touch with dyed local anesthetic eye drops. The slit lamp is used to measure the time taken for the tear film to break up.
6. Slit lamp examination of the “posterior segment” of the eye
The vitreous body and optic nerve head, as well as the retina, vessels and macula can also be examined with the slit lamp and another lens held in front of it. However, for a precise examination of the posterior segment of the eye, the eyes must first be instilled with pupil-dilating eye drops.
The effect of these drops starts after about 20 minutes and lasts for about 3 hours. During this time, you must not drive a motor vehicle or operate dangerous machinery, as your near vision may be impaired and you are more easily blinded. Therefore, please do not drive yourself to the eye examination.
Additional Examinations
1. Optical coherence tomography (OCT) examination
Optical coherence tomography (OCT) is used to examine the optic nerve head, the retina (especially the macula), the cornea or the chamber angle. For this examination, the patient looks into a device with one eye and the various layers of the eye are displayed with it. This can also be used for follow-up examinations.
2. Optical coherence tomography (OCT) angiography
OCT-angiography is used to examine the vessels in the retina in detail. In contrast to fluorescence angiography, no contrast medium is injected into the veins. This can also be used for follow-up examinations. For you, the examination hardly differs from a purely normal OCT examination.
3. Three-mirror glass examination
This examination is performed if you see flashes, shadows or black spots. This examination may also be necessary in case of other diseases (e.g. diabetes, high blood pressure, high myopia). It is a detailed examination of the whole back of the eye and especially of the whole retina. For this purpose, pupil-dilating eye drops need to be applied, as in the slit lamp examination of the “posterior segment” of the eye. Before the examination, the eyes are then made insensitive to touch with local anesthetic eye drops. The examination is then performed with a glass that is placed directly on the eye. This glass contains 3 mirrors – hence the name – with which the complete back of the eye can be seen.
4. Gonioscopy
Gonioscopy is performed when it is necessary to examine the iridocorneal angle (where the intraocular pressure is regulated) of the eye. This examination is performed in case of suspected glaucoma, vascular neoplasms in the eye or a tumor on the iris. Before the examination, as in the case of eye pressure measurement, local anesthetic eye drops will be applied to make the eyes insensitive to touch. After that, a glass is placed on the eye to view the iridocorneal angle. The examination is very similar to the three-mirror glass examination, except that the pupil dilating eye drops are not used in this case.
5. Pachymetry
Here the thickness of the cornea is measured. If glaucoma is suspected, the thickness of the cornea should be measured because the thickness of the cornea may have an effect on the eye pressure measurement. Nowadays pachymetry is performed with an OCT examination of the cornea. However, it can also be measured with a dedicated pachymeter. In this case, as in the case of the eye pressure measurement, local anesthetic eye drops are used before the examination in order to make the eyes insensitive to touch. After the drops a measuring probe is placed on the cornea to measure the thickness.
6. Day pressure curve
If glaucoma is suspected, the eye pressure should be measured at 4 different times of the day to document the course of the eye pressure. For this purpose, appointments are made at different times of the day when you will only come for an eye pressure measurement.
7. Visual field examination
If glaucoma is suspected, or if the visual field is impaired, a visual field examination must be performed. This examination is performed on both eyes separately by covering one eye at a time. With the other eye, the patient looks into a device and must press a button when a point of light is detected. The examination can take up to 15 minutes.
8. Biometry
Biometry involves measuring the length of the eye and the curvature of the cornea. These measurements are used to calculate the power of the artificial lens that will be implanted in the eye during cataract surgery. The measurement takes only a few minutes and must be done before cataract surgery.
Usually, laser biometry is performed. However, if the cataract is very advanced or the area behind the patient’s own lens is clouded, then ultrasound biometry is performed.
9. Corneal topography
In this procedure, the cornea is measured precisely and an elevation relief of the cornea is displayed. Curvatures and bulges of the cornea are shown, which have an influence on the visual acuity. This examination is necessary in corneal diseases but especially in astigmastism when cataract surgery with a toric lens is desired.
10. Pupillometry
The pupillometer is used to measure the size of the pupils under different light conditions (brightness, darkness, twilight). Since the pupil has an influence on the glare sensation, this examination may be necessary.
11. Mesotest
This device measures twilight vision and glare sensitivity. The Mesotest is especially necessary for a driver’s license examination.
12. Ultrasound
In case of poor or no vision in one eye, I can examine the inside of the eye with ultrasound.
13. Schirmer test examination
This examination is performed when an imbalance of the tear fluid is suspected. Small strips of filter paper are placed in the lower eyelid and these left there for 5 minutes.
14. Conjunctival swab
In case of persistent conjunctivitis, a conjunctival swab may be necessary to find the appropriate eye drops based on an antibiogram.
15. Color vision test
This test is performed to check color vision. You will be presented with colorful charts on which you should recognize a pattern or number (Ishihara charts). To accurately determine a color vision deficiency, you may also be given a Farnsworth test in which you arrange colored stones in a row.
16. Stereo vision test
To test your 3D vision, you will be handed a board on which you should recognize various objects (Lang test) or put on special glasses with which your three-dimensional vision can be tested (Titmus test).