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Can lenses be worn with astigmatism?

Astig­ma­tism is a spe­cif­ic oph­thalmic dis­ease in which there is no sin­gle point of focus­ing rays on the reti­na. This is due to the irreg­u­lar shape of the cornea, and much less often — the shape of the lens.

The nor­mal cornea has a smooth con­vex spher­i­cal sur­face. But with astig­ma­tism, the sur­face of the cornea has anatom­i­cal fea­tures — it is irreg­u­lar, not spher­i­cal in shape. It has a toric shape in the cen­ter, so the stan­dard meth­ods of vision cor­rec­tion with con­tact lens­es will not work for the patient.

Con­tact lens­es have been used in oph­thal­mol­o­gy for a long time, but until recent­ly they were not rec­om­mend­ed for patients with astig­ma­tism. This is due to the fact that due to severe or seri­ous visu­al impair­ments, a full fit on the cornea of ​​stan­dard lens­es for cor­rect­ing visu­al acu­ity in patients with astig­ma­tism was dif­fi­cult. Stan­dard lens­es for these patients did not give the desired effect, brought dis­com­fort dur­ing use and could wors­en the con­di­tion of the visu­al ana­lyz­er.

Today, oph­thal­mol­o­gists use spe­cial lens­es, toric lens­es, to cor­rect mod­er­ate and high degree visu­al impair­ment in this pathol­o­gy. The out­er or inner sur­face of such lens­es has a spe­cial shape. Toric lens­es cor­rect corneal astig­ma­tism up to 6 diopters or lens astig­ma­tism up to 4 diopters.

Which lenses are best for astigmatism

Cor­rect­ing visu­al impair­ment in the pres­ence of astig­ma­tism is helped by cor­rec­tion glass­es or the use of con­tact lens­es. When choos­ing the type of cor­rec­tion, it is nec­es­sary to take into account sev­er­al cri­te­ria — this is the type of astig­ma­tism, as well as its stage, fea­tures of visu­al impair­ment. With a mild degree, cor­rec­tion is pos­si­ble due to the use of cylin­dri­cal lens­es or con­tact cor­rec­tion with prod­ucts with an aspher­i­cal shape.

With a com­plex form of astig­ma­tism, for exam­ple, with its mixed type, cylin­dri­cal lens­es will not solve the prob­lem, since the pathol­o­gy of refrac­tion may be accom­pa­nied by hyper­me­tropia or myopia. If there is astig­ma­tism with myopia, the pic­ture is focused in two points, not reach­ing the reti­na. With astig­ma­tism, which is accom­pa­nied by far­sight­ed­ness, two points of focus of the image are formed behind the reti­na. Lens­es hav­ing a toric shape can help in cor­rect­ing this defect.

What is the difference between astigmatism lenses and regular lenses?

For con­tact cor­rec­tion, spher­i­cal, toric, aspher­i­cal or mul­ti­fo­cal lens­es can be used. Con­ven­tion­al prod­uct options will not cope with myopia or hyper­opia, a per­son will notice a dis­tor­tion of the pic­ture on the periph­ery of the image.

To the point

How to choose the best lens­es: advice from doc­tors

Aspher­i­cal lens­es cor­rect vision much more effec­tive­ly, widen­ing view­ing angles due to a snug fit to the cornea and repeat­ing its abnor­mal shape. Such lens­es com­pen­sate for astig­ma­tism with­in 2 diopters, but they can­not cor­rect more severe degrees. To solve this prob­lem, already spher­i­cal types of lens­es are used.

How do lens­es with this pathol­o­gy dif­fer from ordi­nary ones? They can be imag­ined as an ordi­nary ball, which was squeezed from both sides by hands. Where the sur­face of the ball is com­pressed, its cur­va­ture is more pro­nounced than from the side sur­faces, but on the out­side there remains a sur­face in the form of a hemi­sphere. It is the same with lens­es, due to a sim­i­lar shape, they form two opti­cal cen­ters at once. With the pas­sage of light rays, not only the main prob­lem of vision is cor­rect­ed, but also the accom­pa­ny­ing near­sight­ed­ness or far­sight­ed­ness.

Lens Fitting Tips

In the pres­ence of astig­ma­tism, the selec­tion of lens­es should be car­ried out only by an oph­thal­mol­o­gist. It mea­sures a num­ber of stan­dard indi­ca­tors — lens diam­e­ter, radius of cur­va­ture, as well as opti­cal pow­er and cylin­der axis for con­tact lens­es. In addi­tion, it is nec­es­sary to cor­rect­ly select the method of sta­bi­liz­ing the prod­uct in the eye so that the toric lens is clear­ly fixed on the sur­face of the cornea. Any slight dis­place­ment pro­vokes a sharp dete­ri­o­ra­tion in the image.

Mod­ern toric lens­es are pro­duced using var­i­ous sta­bi­liza­tion tech­niques:

• the pres­ence of bal­last — the lens has a small area of ​​com­paction in the area of ​​​​the low­er edge: if a per­son keeps his head in a straight posi­tion, the lens will stand cor­rect­ly, but when the head is tilt­ed or the posi­tion of the body changes, the lens­es will shift, the image will begin to blur (today such lens­es are no longer pro­duced );
• cut­ting off a cer­tain edge of the lens­es so that they sta­bi­lize with the nat­ur­al pres­sure of the eye­lids — such prod­ucts can move when blink­ing, but then restore the cor­rect posi­tion again;
• the pres­ence of perib­al­last — these lens­es have thin edges, they have four seal­ing points that help keep the lens in the desired posi­tion with­out restrict­ing motor activ­i­ty.

What lens options are acceptable for astigmatism

There are many types of con­tact lens­es avail­able today. These can be dai­ly toric lens­es with a high lev­el of com­fort. They cor­rect astig­ma­tism in par­al­lel with far­sight­ed­ness and near­sight­ed­ness.

To the point

When you want a change in appear­ance, col­ored con­tact lens­es can come in handy.

Month­ly lens­es are also used — they are cheap­er than dai­ly ones and have high opti­cal para­me­ters.

Reviews of doctors about lenses for astigmatism

– The choice of a method for cor­rect­ing astig­ma­tism remains with the patient, depends on his lifestyle, age, work per­formed, – says oph­thal­mol­o­gist Olga Glad­ko­va. – Toric lens­es allow you to get clear­er vision com­pared to spec­ta­cle cor­rec­tion of astig­ma­tism. Do not for­get about con­traindi­ca­tions for wear­ing con­tact lens­es, such as inflam­ma­to­ry dis­eases of the ante­ri­or seg­ment of the eye, dry eye syn­drome, when the use of con­tact lens­es is exclud­ed.

Popular questions and answers

We asked ques­tions oph­thal­mol­o­gist Olga Glad­ko­va regard­ing wear­ing lens­es in the pres­ence of astig­ma­tism in com­bi­na­tion with oth­er vision prob­lems.