Myopia pregnancy is a disorder of refraction of the eye with the focus of refractive parallel rays of light in front of the retina, which can become complicated in the gestational period and childbirth. It is manifested by a decrease in visual acuity, blurred display of distant objects, rapid eye fatigue, pain in the eye sockets and forehead area. It is diagnosed using ophthalmological tests, direct ophthalmoscopy, skiascopy, computer refractometry, biomicroscopy and echography of the eyeballs. With dystrophy of the inner shell of the eye, laser coagulation is performed, followed by the appointment of peripheral vasodilators, antiplatelet agents, cysteine derivatives, vitamin therapy.
Myopia (myopia, myopic refraction of the eye) is the second most common ophthalmic disease in adult women. By the beginning of the reproductive period, the disease is detected in 25-30% of patients, 7.4-18.2% of whom suffer from high-grade myopic refraction. Myopia is diagnosed in 16.9-38% of pregnant women, is the second in the structure of extragenital disorders during gestation with a proportion of 18-19%. With a complicated course, it serves as one of the main reasons for performing a cesarean section. Specific changes in hemodynamics during pregnancy and significant physical exertion experienced by a woman in the second period of childbirth provoke peripheral retinal dystrophy and detachment in some patients with myopia, which can cause complete loss of vision.
Causes of myopia pregnancy
Myopia occurs due to the discrepancy between the refractive power of the optical system of the eyeball and the length of its axis. The disease, as a rule, occurs long before the onset of pregnancy during increased eye growth in preschool girls and gradually progresses depending on the loads on the visual system. According to most experts, myopia has a hereditary nature, although a dysembriogenetic origin of the disease is also possible. Predisposing factors for the development of myopia are genetic defects in which there are:
- Elongated eye shape. An increase in the anteroposterior axis of the eyeball is usually noted with undifferentiated connective tissue dysplasia and leads to focusing of light rays in front of the retina. As a result, the clarity of perception of objects located in the distance is disrupted. With excessive stretching of the posterior wall, dystrophic changes occur in the macula, partial or complete detachment of the retina, and other disorders on the fundus that affect the choice of delivery method.
- Excessive refraction of light rays. In this case, the eyeball has normal dimensions, light rays are focused in front of the inner shell of the eye due to abnormal refraction by the cornea, the outer and inner surfaces of the lens. The situation is aggravated by overwork of the oculomotor muscles during intense visual work at close range in poor lighting conditions. Overload of vision causes a functional spasm of accommodation, which, in the absence of correction, provokes an elongation of the anterior-posterior size of the eye.
- Increased intraocular pressure. In 1-2% of cases, myopia develops against the background of ophthalmic hypertension in women with systemic progressive angiomatoses. Such myopia is congenital, has a dysgenetic origin, is associated with a violation of the formation of the eyeball during fetal development. The severity of refractive error reaches 5-6 diopters. The disorder is often combined with juvenile glaucoma, which limits the choice of surgical methods of vision correction and worsens the prognosis of the disease during pregnancy.
The progression of myopia pregnancy is facilitated by increased tissue elasticity under the action of relaxin and progesterone, leading to even greater elongation of the eye and stretching of its posterior wall with the appearance of peripheral vitreochorioretinal dystrophies. During gestation, blood flow in the ciliary body, which regulates the hydrodynamic parameters of the eyeball, worsens, which affects the level of intraocular pressure. Reversible and organic changes in the structures of the fundus associated with the formation of the fetoplacental complex and the corresponding redistribution of blood in the pregnant woman’s body are detected.
Due to arteriole spasm, the hemodynamics of the eyes changes significantly. The physiological course of pregnancy is characterized by functional disorders, which are manifested by changes in the course and caliber of the vessels of the retina. Patients with complications of gestation may have organic disorders in the form of acute obstruction of the retinal arteries and their branches, hemorrhages, edema and retinal detachment. Normally, refraction in pregnant women does not change. In the second half of pregnancy, in the presence of gestosis, accommodation may decrease by more than 1 diopter. This is caused by an increase in the refractive ability of the lens due to its swelling and curvature due to increased permeability under the action of progestins and estrogens.
To make a decision on the tactics of accompanying a pregnant woman in obstetrics, the systematization of myopia variants by severity is most often used. This is due to the direct dependence of the frequency of severe ophthalmic complications that occur in natural childbirth on the severity of visual disorders. There are three degrees of myopia:
- Weak myopia. The refractive error is up to -3 dptr. It is the most prognostically favorable option. During the gestational period, the woman should be examined twice by an ophthalmologist. In the absence of other obstetric and extragenital contraindications, natural childbirth is recommended.
- Average myopia. Visual impairment reaches 3.25-6 dptr. In the absence of signs of progression of myopia, the patient can usually give birth on her own. To dynamically monitor the condition of the retina, the pregnant woman is examined three times by an ophthalmologist — at registration, at 20 and 36 weeks of gestation.
- High myopia. The severity of refractive errors exceeds 6 dptr. Myopia of a high degree is most often complicated by dystrophic damage to the retina, its detachment. The preferred method of delivery is Caesarean section. Ophthalmological examination is performed three times.
The disease is manifested by insufficient clarity of the display of objects located at a distance, while maintaining satisfactory near vision. Only with very high myopia does the patient notice the vagueness of the text and small objects viewed up close. With an increase in the severity of the disease, complaints of rapid eye fatigue, a feeling of discomfort, headaches, painful sensations in the forehead, eye sockets are more common. The development of possible complications is indicated by the appearance of light sensations (flashes, flickering, sparks) or photopsies (non-objective luminous or shiny dots, spots, shapes), periodic blurring or floating blurred vision, distortion of the shapes of the objects being viewed, the loss of individual fragments of the image in the field of view.
Myopia does not have any effect on the course of gestation and childbirth, however, the quality of vision of a pregnant woman may deteriorate with the development of gestosis or the occurrence of loads associated with labor. The main complications of myopia during pregnancy are central and peripheral vitreochorioretinal dystrophy (retinoschisis, tears of the retina, lattice changes, mixed variants of the disorder), edema of the optic nerve disc, acute attacks of glaucoma, retinal hemorrhage and detachment. The probability of dystrophic changes increases in the presence of anemia of pregnant women. In the most severe cases, complete loss of vision is possible.
Usually, the patient knows about the presence of myopia even before being registered in a women’s clinic, in extremely rare cases, the disease is detected during pregnancy. The main task of the diagnostic search is to assess the degree of progression of myopic refraction and to identify pathological changes in the fundus. The most informative research methods for myopia pregnancy are considered:
- Visual acuity check. Visometry allows you to quickly assess the degree of vision loss and the severity of myopia, monitor these indicators in dynamics, and select suitable corrective lenses. The results of the study are evaluated comprehensively taking into account the data obtained by other methods.
- Direct ophthalmoscopy. A detailed examination of the fundus reveals vasoconstriction and possible degenerative-dystrophic changes in the retina, in the presence of which the risk of its peeling increases. For a detailed study of the peripheral divisions, maximum medicinal mydriasis is used.
- The study of refraction. Skiascopy and computer refractometry are used to evaluate the parameters of refraction of light rays when passing through optical media and structures of the eyeball. With their help, the features and the magnitude of the refractive power of the optical system are determined with high accuracy.
- Biomicroscopy with a Goldman lens. The method allows a detailed assessment of the condition of the retina, including its peripheral parts. The examination is indicated for patients with elongation of the eye and high myopia for timely detection of various forms of dystrophy and areas of retinal detachment.
- Ultrasound of the eyeballs. Various methods of echoophthalmoscopy (one-dimensional A-scan, two-dimensional B-scan, three-dimensional AB-scan in combination with ultrasound biometry) provide complete information about the anatomy and size of the organ. With the ultrasound of the vessels of the orbit, the features of blood flow are visualized.
Treatment of myopia pregnancy
Women with mild and moderate myopia usually do not receive special therapy, it is recommended to be monitored by a specialist for timely detection of rapid progression of the disease or pathological changes in the retina. The main therapeutic tasks in the management of patients with high myopic refraction are to improve metabolic processes and microcirculation in the structures of the fundus, blocking areas of lattice dystrophy combined with vitreomacular traction, and retinal tears that do not tend to self-limitation. Taking into account the indications in the prenatal period , such pregnant women are assigned:
- Drug therapy. To prevent or reduce retinal dystrophy independently or after surgery, peripheral vasodilators, antiplatelet agents, cysteine derivatives, multivitamin complexes are used. By improving microcirculation, such drugs reduce the risk of degenerative disorders.
- Preventive laser coagulation. The operation is performed before the 35th week of pregnancy with thinning of the retina or the presence of micro-tears. With the help of a laser, weak spots and ruptures are strengthened due to the formation of scars that firmly bind the retina to the cornea, prevent its exfoliation during childbirth and stabilize dystrophic changes.
- Scleroplasty. Strengthening of the sclera with the help of special plates or gel is usually performed at the stage of prenatal preparation. In exceptional cases, with the rapid progression of myopia, it is possible to operate on a pregnant woman. The intervention makes it possible to reduce the stretching of the back of the eye with the retina and prevent its detachment in the posterior period.
Other methods of surgical correction of myopia are not indicated for pregnant women . With intense vomiting caused by early toxicosis, the presence of gestosis, anemia and other complications that can aggravate the course of myopia, active therapy of the detected pathology is mandatory. The rapid progression of severe changes in the inner lining of the eye that can lead to blindness, with therapeutic resistance of the background disease, serves as the basis for termination of pregnancy.
In the absence of obstetric indications, women with unchanged fundus or peripheral dystrophy of the retina, which does not require surgical correction and does not progress during pregnancy, are recommended to give birth independently with epidural anesthesia. Regardless of the degree of myopia, caesarean section according to absolute indications is performed when the retina is detached in real childbirth, laser coagulation is performed later than 30 weeks of pregnancy or on a single sighted eye. In other cases, the decision on the method of delivery is made jointly by an optometrist and an obstetrician-gynecologist, taking into account the opinion of the pregnant woman. As an alternative, natural childbirth with the switching off of attempts (perineotomy, the imposition of obstetric forceps or vacuum extraction of the fetus) can be considered.
Prognosis and prevention
The probability of developing ophthalmic complications depends not so much on the severity of myopia as on changes in the retina. The risk of degenerative and dystrophic processes is higher in pregnant women with high myopia. For preventive purposes, early registration, scheduled and according to the indications of an optometrist, timely correction of the pathology of the retina and pregnancy complications (toxicosis, gestosis, anemia) are recommended. Pregnant women with myopia are recommended to reduce the visual load, limit the time spent at the computer and the use of gadgets, perform special eye exercises.