Eye pressure keeps the retina stable. It also participates in the process of microevolution of metabolism. If the level of pressure decreases or rises, this may indicate the development of serious diseases that affect the quality and visual acuity.
Intraocular pressure normal
Intraocular pressure (IOP) is also called ophthalmotonus. Thanks to him, the shells of the eye are nourished. It also maintains the spherical shape of the shell due to the process of outflow and influx of intraocular fluid. And it is precisely the amount of this fluid that determines the level of IOP.
By measuring eye pressure, you can detect its level both at home and in the hospital. However, it should be understood that during the day the indicator may vary. Usually it is higher in the morning, and lower in the evening. Normal IOP, in both children and adults, regardless of gender, varies between 10–25 mmHg. Depending on the time of day, a slight deviation is allowed, but not more than 3 mm Hg.
Who should regularly carry out the procedure
A person should regularly measure eye pressure if he has:
- Glaucoma.
- Violations of the nervous system.
- Cardiovascular and endocrine diseases.
- Decrease in visual acuity.
- Headaches that are accompanied by pain in the eyes.
- Squeezing the eyeball.
- Dry cornea, its redness and fogging.
- Eyeball retraction.
- Pupil deformity.
A device for measuring eye pressure may show false information if the patient is under the influence of alcohol or drugs. It also makes no sense to take measurements if the patient is aggressive and overexcited. Another contraindication for the procedure is the presence of an infectious, bacterial or viral disease of the fundus and mucous membrane.
Diagnosis by palpation
In some cases, the doctor takes an eye pressure measurement by palpation. With its help, you can determine the ophthalmotonus only approximately. During the procedure, the level of intraocular pressure is assessed using the fingertips.
The stages of the procedure are as follows:
- The patient looks down.
- The doctor rests on the forehead with his fingers, and puts the index on the eyelid.
- The ophthalmologist easily presses the eyeball.
If the doctor feels small impulses of the sclera and fundus, this indicates that the IOP is slightly reduced or is within normal limits. If, when pressing on the sclera, it is necessary to apply certain efforts, then the pressure is higher than normal. In this case, the pushes with the index finger are not felt.
Thanks to palpation, you can find out the level of degree of density of the sclera. It can be moderate, normal, elevated, and even stone. With ophthalmotonus, the doctor also discovers a softened sclera, which can be soft, very soft, or excessively soft.
Ophthalmologists usually use this diagnostic method when there are contraindications for using other methods. In addition, using this method, it is possible to measure fundus pressure at home without using special instruments.
Method for diagnosing the level of IOP according to Maklakov
In this case, you need a Maklakov tonometer to measure eye pressure. However, such a device is not always appropriate to use. For example, if a patient has inflammatory diseases or an eye surgery has recently been performed, tonometry is strictly prohibited.
The procedure according to the Maklakov method is as follows. To eliminate pain, local anesthesia is used. Then, for 5 minutes, the patient lies on the couch for examination. The examination is carried out with the help of a device consisting of special hollow metal cylinders-weights, which weigh 10 g each. They are dipped in a special pigment paint. The tonometer is located right in the center of the corneal part. First, the right eye is examined, and then the left. At the same time, the weights are pressed on the cornea, leaving paint on it. After that, the ophthalmologist makes a print on the paper and measures the indicator using a ruler to find out how much dye disappeared after touching the eyeball. After all the manipulations, the eyes are instilled with drops that have a disinfecting effect. This completes the measurement of eye pressure.
The results should be interpreted as follows. The softer the eyeball, the more paint remains on it. This indicates a decreased IOP. This tonometer allows you to get accurate data. Typically, measurements are taken in the morning and evening in order to determine whether the patient has glaucoma.
We measure IOP at home using an ICare tonometer
Today it has become possible to take eye pressure measurements at home. This can be done using the ICare tonometer. It helps those people who cannot regularly go to the doctor to measure intraocular pressure. This is especially important for those who are diagnosed with glaucoma. Statistics have shown that approximately 50% of patients suffer from increased IOP just when they are not at the doctor’s appointment.
The ICare tonometer is very convenient to use, when carrying out the procedure with it, you will not experience pain. It is also completely harmless. The device allows you to quickly get accurate results.
Diagnosis is carried out using a special sensor that is in contact with the cornea of the patient. It is disposable and easy to replace. Due to the fact that it is very small and weighs a little, measurements will not cause any discomfort. The advantages of the device are as follows:
- Allows you to instantly measure IOP with high accuracy.
- There is no need to worry about anesthesia before use.
- It is absolutely harmless to humans and reliable.
- Does not cause reflex contractions.
- It is equipped with disposable sensors, reducing the risk of infection.
- Saves data on 10 previous measurements, displays them on the screen.
- Easy to operate and battery operated.
- It emits sound signals: single and double. The first indicates a successful measurement.
- It has a very low weight.
- It is equipped with an additional accessory for storage and transportation of the device.
The best appliances for home use
Currently, there are many devices for measuring eye pressure at home. Here are those that have proven themselves in the market:
- TVGD-01. Allows you to very quickly measure IOP through the eyelid. It does not require the use of antiseptics, since it does not contact the cornea.
- TVGD-02. It is a more advanced model and was created specifically in order to diagnose glaucoma. Quite often used by doctors who provide emergency medical care, as well as in pre-medical examination rooms. Now approved for home use.
- TGDts -01 and IHD - 02. These devices for home measurement of eye pressure are analogues. They are no worse than stationary appliances. The weight of the devices is 89 g, they give accurate data in 3 seconds.
- IHD - 03. This home device for measuring eye pressure is an innovation and has appeared recently. It is equipped with an advanced display and has advanced functionality. With it, you can easily check the level of IOP, even in children. It is very small, and therefore suitable for use at home.
Contactless devices
Non-contact measurement of eye pressure is carried out using special instruments that allow you to quickly identify pathology. For their use, coloring substances and anesthesia are not required. The technique is gentle, because it eliminates damage to the cornea. For example, the model of the tonometer TVGD-01 does not provide for contact with the corneal layer.
The advantages of this device are as follows:
- The cornea is not infected.
- The outer surface of the device is highly resistant to chemical disinfection.
- The procedure is not traumatic.
- The measurement process is completely under the control of electronics.
- Does not require anesthesia.
- Suitable for patients who have sensitive eyes, and even for repeated use.
- Allows you to measure the level of IOP and sitting and lying.
- Suitable for use if the patient has allergic reactions to anesthetics and there are contraindications for performing corneal tonometry.
Optical Coherence Tomography
It is an innovative non-contact technique with which you can explore different structures of the eye with high resolution. During the procedure, infrared light rays enter the eye, and then prints are reflected. Then there is interference, which captures and transforms OCT.
However, this method sometimes produces false positive or negative results. Therefore, in order to obtain truly accurate data, it is necessary to conduct additional studies. OCT allows you to identify minor deviations of the optic nerve. With its help, you can diagnose glaucoma and other diseases in the early stages. During the procedure, the patient should fix his gaze on the label. Next, several scans are carried out and the specialist selects the best image for quality. After that, maps, protocols and special tables are compiled, based on which we can talk about the presence of changes.
Goldman's apparatus
Another tonometer for measuring eye pressure is the Goldman device. It is based on applanation tonometry. The device is mounted on a slit lamp. It also has a special prism.
The patient is anesthetized and a fluorescein solution is instilled. After this, a prism is applied to the cornea. The specialist carefully adjusts the degree of prism pressure on the cornea. It is flattened until a convergence of colored half rings at one point occurs. Further, the level of ophthalmotonus is determined using the instrument scale.
Impression device
The basis of the operation of such a device is the Schiotz method. The level of ophthalmotonus is measured by pressing on the cornea with a special rod that has a certain weight. Here, a prerequisite is anesthesia.
During the procedure, a rod with a weight is applied to the eye. The strength of the ophthalmotonus contributes to its fluctuation, while the arrow on the scale deviates. To interpret the results, the data obtained are compared with the performance of special tables.
Tonometer IOP "Pascal"
With the help of such a device, contour dynamic tonometry is performed. Here, flattening of the corneal layer is not provided. The device is mounted on the optical axis of the slit lamp. The specialist sees where the border is between the tip of the device that determines the level of ophthalmotonus and the cornea. The tip is equipped with a special sensor that generates a signal. The device emits a sound signal, the higher it is, the higher the IOP. He listens for five seconds.
Finally
Tonometers for measuring internal eye pressure indicate the rapid development of medical technology. After all, the first mechanical devices were replaced by modern electronic devices, which are very convenient and easy to operate, as well as safe to use. With the help of such devices, serious eye diseases can be detected even at an early stage.