One of the main types of diagnostic ophthalmological studies is the measurement of corneal curvature, which is performed using an ophthalmometer. This test allows you to determine the magnitude of astigmatism in a patient, i.e. one of the main visual defects. Using such a diagnostic device, it is possible to accurately assess the refractive power of the eye. In this article, we will describe in more detail how an ophthalmometer works and what kind of test is performed with it.What is the principle of operation of ophthalmometers?
An ophthalmometer is also often referred to as a keratometer. This device has long been used in ophthalmological diagnostics. The first such equipment was designed in the 19th century by the German physiologist Hermann von Helmholtz. The principle of operation of this type of device is very simple. To determine the degree of corneal curvature, the device checks how well the cornea performs the function of a convex mirror.. During the examination, the device projects various shapes onto the cornea and analyzes their reflections. The task of the examining ophthalmologist is to connect the two figures in the reflection so that they are in line with each other. Then, after turning the shoulders of the device by 90 percent, the reflections of the figures should remain unchanged. If this does not happen, the patient has an abnormal curvature of the cornea, which means that he has astigmatism.
Ophthalmometric examination allows you to determine the refractive ability of the eye, or rather the ability to perceive a light wave refracted after passing through the eyeball. So the examination is really aimed at determining the ability of the eye to correctly perceive light falling on it, which is the first stage of creating an image in the eye. The cornea and lens of the eye play a crucial role in the refraction of light rays. The occurrence of corneal curvature anomalies does not allow the eye to simultaneously focus rays on the retina, which makes the patient's vision blurry.The exact course of the examination using an ophthalmometer
Examination using an ophthalmometer is completely non-invasive and painless. It also does not require any prior preparation of the patient, so it is easy to carry out during any routine examination in the ophthalmology room. During the ophthalmometric examination, the patient remains in a sitting position. An abnormal corneal curvature measurement indicates that the patient has astigmatism. If the reflections of the figures clearly overlap after turning the shoulders of the device, it means that the patient has simple astigmatism. This is a signal that the vertical axis of the cornea strongly refracts the light beam. If the reflections of the figures on the surface of the cornea clearly diverge, then the patient is diagnosed with reverse astigmatism, which consists in the fact that the vertical axis of the cornea refracts the light beam less. For beginners, clarity matters more than inflated numbers. Many onboarding guides include 1xbet free promo code while explaining the 100% bonus of up to €130 available for sports bets. In addition, the casino package of $1950 with 150 free spins gives new users enough room to explore slots and live dealer games without feeling rushed.