DiagnosisFirst of all, it is necessary to consult an ophthalmologist to determine visual acuity and a comprehensive assessment of the eye condition. Common diagnostic methods include:-
- examination of eye structures
- refraction study
- visometry with and without correction
- skiascopy (shadow test) with spherical or cylindrical lenses
- refractometry with artificial pupil dilation
- biomicroscopy of the eye to determine the causes of astigmatism,
- ophthalmoscopy to study the state of the vitreous body
- Ultrasound of the entire eye and ophthalmometry (determination of its size).
- Computerized corneal topography to determine the degree of corneal defects
Astigmatism treatmentOphthalmologists are involved in the diagnosis and treatment of astigmatism. Several basic types of correction are applied:
- spectacle correction
- lens correction
- microsurgical correction
- laser surgery
Astigmatism typesAstigmatism is of different types:
- Simple:- It affects only one axis.
- Compound:- When it is associated with another pathology. There are two types:
- Myopic: astigmatism associated with myopia
- Hyperopic: associated with hyperopia
- Mixed:- It affects several axes. One axis focuses in front of the retina and the other behind.
- In the regular, the main meridians are perfectly perpendicular to each other (they form an angle of 90 degrees). Most astigmatisms are regular corneal, which means that the front surface of the eye is shaped like a football.
- In irregular astigmatism, the main meridians are not perpendicular, and this may be the result of an injury to the eye that caused the cornea to heal, surgery, or keratoconus
- Low astigmatism: up to approximately 1.25 diopters
- Average astigmatism: from 1.50 to 2.75 diopters
- High astigmatism: more than 3three diopters
Depending on the patient's age, visual acuity, and the type of astigmatism that he suffers or the graduation he presents, he may or may not perceive symptoms. In general, the main symptom is blurred or distorted perception, both of distant and close objects. This blurred vision tends to be more pronounced at night or in low light conditions. The problem of seeing small details at all distances is also common.
In cases where it appears associated with hyperopia, it is common for the patient to suffer:
- Visual fatigue
- Itching and stinging of the eyes.
- Gritty sensation.
- Eye pain
- Dizziness or headaches due to overexertion of the eye to focus images. Headaches usually appear.
Astigmatism symptoms in children
- confusion of letters when reading or writing
- complaints of visual impairment
- distortion of objects, their fuzziness
- an unpleasant sensation near the eyebrows
- rapid visual fatigue
- a feeling of pain in the eyes
- discomfort from wearing glasses with their frequent replacement
Common symptoms in adults
- blurred vision
- tired eyes
- loss of picture clarity
- uneven objects and deformation
- blurry picture
- pain in the eyes with redness
- double vision during visual stress
- difficulties in the determination of far objects
Astigmatism by origin is congenital, hereditary, and acquired. Acquired astigmatism results from:
- corneal scars
- eye injuries
- eye surgery
- corneal dystrophy
- corneal opacities
- keratitis (inflammation of the cornea)
With congenital astigmatism, play a role:
- uneven pressure of the eyelids on the eye apparatus
- disruption of the oculomotor muscles
- impaired of the formation of the bones of the orbit
Your eye has two structures with curved surfaces that bend (refract) light onto the retina, which makes the images
• The cornea, the clear front surface of your eye along with the tear film
• The lens, a clear structure inside your eye that changes shape to help focus on near objects
In a perfectly shaped eye, each of these elements has a round curvature, like the surface of a smooth ball. A cornea and lens with such curvature bend (refract) all incoming light equally to make a sharply focused image directly on the retina, at the back of your eye.
Can astigmatism be prevented?
It cannot be prevented, but it must be diagnosed and corrected in time to prevent the symptoms it causes from worsening.
How is astigmatism corrected?
Astigmatism can be corrected by different treatments and, depending on the degree that is suffered and the patient's preferences, you can choose one or the other.
- Astigmatism can be corrected with toric contact lenses or glasses. In both cases, the lens graduation must be adequate for the degree of astigmatism that the patient presents. Also, in the case of suffering from compound astigmatism (which is also accompanied by myopia or hyperopia), the lens graduation must be adequate to correct all the patient's vision problems at the same time.
- If a person with astigmatism wants to stop wearing glasses or contact lenses, there are several surgical options. Astigmatism is corrected by laser refractive surgery through different techniques, such as Lasik or Surface Techniques (PRK / Lasek, or it can be corrected with toric intraocular lenses. All of these techniques are safe, painless, and efficient. In all cases, it should be the ophthalmologist who, according to the characteristics of each patient, determine which is the most appropriate for each situation. The treatments are personalized and allow correcting several refractive errors in the same intervention.
How is the degree of astigmatism of a patient known?
- Ophthalmologists calculate the astigmatism grade with different methods. One of them is a test called retinoscopy, which consists of projecting a beam of light that moves vertically and horizontally into the eye. The examiner observes the movement of the retina reflex and places lenses in front of the eye until the movement of the reflex is neutralized.
- Currently, this process is no longer carried out manually but is carried out through the use of devices that perform the measurement automatically, which translates into a much more specific and accurate diagnosis since the part subjective characteristic of traditional manual tests.
Can I have astigmatism and not know it?
- It is possible for a person to suffer from mild astigmatism and not come to know it, especially in younger patients. In the case of children, whenever the adults in their care (parents or teachers) suspect any symptoms or simply, as a preventive measure, it is necessary to carry out regular eye examinations to make sure that their vision is optimal.
- Some adult patients may also have mild astigmatism without showing any symptoms. For this reason, it is necessary to have regular ophthalmological examinations, including an eye fundus to assess the state of the retina. The goal of these check-ups is to make sure that you do not suffer from diseases or visual defects, especially refractive problems, such as myopia, hyperopia, astigmatism or presbyopia, or eyestrain.
Up to how many diopters of astigmatism can be corrected with laser surgery?
- The amount of astigmatism grade that can be removed by laser surgery will be largely determined by the anatomical characteristics of the patient's eye. Generally speaking, ophthalmologists point out that there is no diopter limit to be corrected by laser surgery for astigmatism.
- However, it will always be the surgeon (with the data from the preoperative tests performed in the first consultation) who decides if it is feasible to correct all diopters by laser. Also, it must be taken into account that the doctor can choose different procedures to correct the diopters of astigmatism. It can be corneal surgery with Excimer laser (Lasik or PRK / Lasek Surface Techniques) or intraocular surgery for the implantation of intraocular lenses.