The problems of poor sight and squint in children touched the minds of Russian physicians long ago. In 1829 Dr. A. Dobrjansky recommended that his patients occlude the healthy eye in cases of squint and poor sight.1 However, all similar proposals and even the surgical correction in that time were spontaneous and symptomatic, until R. Katz in 1909, E. Fisher in 1923, and others2 started regular correction and treatment of squint and amblyopia on scientific grounds and clinical experience of foreign (J aval, 1896; A. Graefe, 1897; Worth, 1903; et al) as well as prominent Russian ophthalmologists and physiologists like Bellarminov,3 Krukov,4 Setchenov, and Pavlov,5 who made considerable progress in theory and praxis of this field.
At the start of this century, however, the doctors in Russia, as a rule, only treated those patients who came to visit them with complaints and symptoms or with complicated and sometimes intractable conditions. Visual function often deteriorated due to the shortage of free medical aid and staff in old Russia. There were practically no prophylactic treatment measures available. After 1917, the people were granted medical aid free of charge, and ophthalmologists started their efforts on the way to early mass treatment and preventive measures.
The routine rules and methods of examination and treatment of patients were established and organized according to the investigations of L. Sergievsky and E. Fisher. 2'6 S. Kravkov, a well-known Soviet physiologist, has achieved and published many discoveries in psychophysiology of vision.7 In 1932, V. Filatov proposed a new form of special supervision called dispensarization8 for eye patients who need continuous and regular close attention by the ophthalmologist to protect their eyes from sudden or imperceptible deterioration. This approach has been used all over the USSR in patients with glaucoma and myopia gravis, and later also in patients with squint, amblyopia, and some other diseases. Active prevention became the principal method and was used in addition to passive treatment, correction, and surgery, if necessary. The doctors have to see healthy people to discover early stages of eye disfunctions long before the child starts to complain or his parents note complications.
Efforts in the protection of child health were renewed and extended after the Second World War when the government directed all medical staff to give extraordinary attention to preventive measures, particularly in the field of pediatric ophthalmology in progressive myopia, squint, and amblyopia. Sergievsky, A. Sawaitov, and others9-1 1 emphasized the importance of proper examination of ocular functions and improvement of school conditions as well as medical propaganda.
At present, ophthalmologic screening of school and preschool children is compulsory all over the country at least once a year.12-14 The special examination routine is now distributed by the Helmholtz' Ophthalmic Institute.15 A chart containing a history with all information about the congenital and hereditary circumstances, onset features, previous treatment, and correction must be completed for every dispensarized child. On examination, the doctor fills in data on general health and eye function such as refraction, accommodation, motility status, fixation, localization, central field, etc. The type of squint and amblyopia are noted after convergence is tested, and field of motility, tangent screen, coordimetry, fusion, and correspondence as well as positive or negative trace (after) image tests are checked.'6 Special stationary observation and instrumental examination such as ERG, EEG, impulse, or rheocyclography are performed if possible.17-19
Soviet inventors have contributed many original devices and instruments for physiologic examination and treatment (discussed later under amblyopia), most of them made in forms of toys or plays to attract the child's attention. OPD examination includes vision tests, external examination and, possibly, some of the tests mentioned above. The refraction is done under cycloplegia long- (atropine 1%) or short-lasting (homatropine 4%).20
The preventive measures usually start at preschool age of five to six when the eye is not used as yet for much work.21'22 Good results were achieved in a group of 8,396 children who underwent early optic correction of ametropias and regular treatment for eight years in special kindergartens run by trained nurses.23 All district ophthalmologists, school doctors, and other staff physicians have to take part in mass campaigns to detect eye problems in preschool children with the help of the population, the Red Cross, and the local authorities. The pediatric ophthalmology units, being situated in regional cities and large towns, organize and control the campaigns. They carry the load of detailed examination and treatment at OPD orthoptic clinics and after admission in regional hospitals. The quantity of premises and staff depends on the population. The Orel region, for example, with a million inhabitants has, in addition to its general ophthalmologic service, one inpatient service (40 beds, 5 doctors, 12 nurses) and 3 OPD units entirely devoted to pediatric ophthalmology. There is, in addition, a central OPD unit as a part of the regional hospital.
Fig. 1. The author operating a refractometer.
The three pediatric ophthalmologists of the city cooperate in organizing the screening at schools and kindergartens, and attend the OPD to see patients and those who have been found to be in need of special examination and treatment during the screening. They also carry out the medical propaganda among the parents and teachers. The regional hospital doctors are also obliged to check on district ophthalmologic units, to organize the rural ophthalmologists for preventive work, and to perform the examination of rural patients selected during rural screening at local OPD's at least twice a year. The work in villages and districts is more difficult, of course, and takes much more time and doctors24 than the stationary work in larger centers.
It has been found that the stationary patients vary nosologically. In small cities there are more possibilities for hospital admission to treat myopia, squint, and amblyopia. In larger cities the beds of pediatric units are mainly occupied with congenital and traumatic cataracts (16.9 per cent), diseases of the outer eye (22.6 per cent), lacrimal diseases (13.4 per cent), corneal diseases (8.8 per cent), and injuries (8.4 per cent). For the group of neuroretinal patients the figure was 8.2 per cent, composed of only 3.9 per cent of squint, ametropias, and amblyopia25 because most of these diseases are treated in OPD units. In most cases, the number of beds and staff is sufficient to provide the examination, treatment, and preventive measures, free of charge except for the cost of eye glasses, for all children of a region.
Fig; 2. The author's proposal for vision testing: Letters, rings and a new chart with an airplane made according to precise measurements.
Ametropias and Myopia
In our first review, it was mentioned that refractive errors and especially myopia are common causes of poor sight in children.26 In USSR a classification by E. Tron and A. Dashevsky27 is used which distinguishes four groups of ametropias: (a) axial; (b) refractional; (c) mixed; and (d) combined, according to the size of the eyeball, refraction and other factors.63
Investigations in Moscow28 have proved that the newborn child has an undeveloped eye with a visual acuity of about 20/5000 and the size of the eye and its vision approach normal figures only at age 14. Myopia develops as a response to the use of the eyes at study. F. Erisman was the first who explained details of the development of myopia under the influence of conditions and internal causes.29 He vigorously organized measures to improve working conditions in schools according to his theories. light sources and desks were designed to ensure proper posture of pupils.13'14'30'41 Intensive reading without sufficient light affects 90 per cent of pupils,3 * »3 2 and changes the percentage of myopia from 6 to 22.5 in 10 years of middle school. Village schools, however, show a smaller increase. Special devices33 were used to show that accommodation plays a role in the development of myopia.63
The complications of high myopia are well known. The rapid increase is considered itself a complication.34 The general condition can go along with minimal changes in blood pressure and blood volume of the eye, lack of vitamins and microelements, and diminution of biologic and phagocytic activities.35'36 The eye changes can be discovered with graphic methods.3 7 In certain patients, ocular tension and ERG may indicate the progressive type of myopia and retinal degeneration.38,39
Many systemic and infectious diseases as well as physiologic changes in the young organism aggravate myopia. Rickets and rheumatism40-42 are examples. This demands general examination and treatment of all systemic diseases and defects in progressive myopia. Treatment of myopia not only includes the prescription of glasses but also hygienic and orthoptic measures43'44 which are described in the next part of the review. The treatment of the body as a whole and the eye stops or diminishes changes in the vitreous and chorioretinal tissues, or prevents them in the first place.63 The optic correction of myopia depends on individual data of accommodation, anisometropia, amblyopia, and other functions. The doctor evaluates them and prescribes a lens that is optimal for study and that causes minimal disturbance of the eye. Intraocular muscles may try to increase or lessen the power of a lens, but astigmatism always has to be corrected.4 5"4 7 The rule to avoid high concave lenses is not always valid, but the full correction for constant use48 may increase myopia due to extra accommodation.49'50 Sometimes prescription of bifocals with full correction for distance only is used. There is, thus, no strict routine, and there presently is much discussion on the problems of proper correction of myopia with consideration of theory, physiology, and experience in the ophthalmologic literature of the USSR.
The following methods are used in the general treatment of myopia:
1. Tissue therapy after V. Filatov, sometimes antireticular serum, Hemo-protein and other stimulating injections;
2. Osmotic intravenous use of glucose (dextrose), sodium and other salts, often combined with the supplements listed under No. 3;
3. Vitamins, iron, iodine, potassium, and some microelements.
4. Rutin, intermedin, hormones, and desensibilizing drugs;
5. Oxygen, ultraviolet radiation as well as electric and other physical procedures.s,'S2
Especially common is the use of biogenic stimulants51 which are contained in specially prepared vegetable or animal tissues. The sterile preparations, extracts of aloe, OMB, Fibs and others, are for daily subcutaneous injections during 30 to 45 days. They are completely harmless, are effective in all chronic degenerations, and improve the biological activity of the body. They sometimes cause clearing of tiny opacities and improve vision. Special experiments at the Filatov's Research Institute in Odessa53'54 showed these stimulants to strengthen scleral fibers, making them resistant and strong. This was shown in 70 per cent of clinical observations.
The prophylaxis against myopia starts with special rules of education. Restriction of reading is enforced by teachers and parents. Lessons by radio, recorded tapes, etc. are used instead. The role of proper hygenic conditions is well known,55-58 and there are official laws for lighting, desks, and other standards to be observed in school. Special attention is paid to children with poor sight who need even more than 150 Lux of lighting for reading, recommended as a standard for children with normal vision. There are now sufficient premises to provide daylight for the principal lessons.
The child's retina is certainly most active in the first two hours of study.s9 Then the activity is reduced, causing a weakness of functions. This means that the itinerary for lessons must contain alternately visual, audial, and physical exercises.
Preventive measures in the USSR already have caused a percentage decrease of myopic scholars. Myopia was stopped or slowed in its rapid increase in many cases. Preventive means are especially necessary for the work of preschool babies. Excellent results were reported by A. Dashevsky to Dnepropetrovsky55'60 who observed these measures accurately for a decade or more. We have introduced similar measures in the Orel region for four years. All preschool and school children are screened to select ametropias and to examine and observe all cases of myopia and amblyopia under dispensary supervision. Visits to districts helped to bring these measures to children whose parents were unable to bring and keep the children in the city. All general ophthalmologists in remote districts were instructed for the purpose of this mass campaign. Only a few years have passed, and there still are many difficulties in performing all desirable measures, but already we see the first favorable results in this task.
Accommodative spasm is common in school children.6! The diagnosis and treatment is composed of cycloplegics, hygienic conditions, and use of convex temporary glasses and concave lenses for training of accommodation. Atropine, in some patients, seems to relieve the spasm but no doctor should rely only on this routine drug.6 2
Strabismus and Amblyopia
The causes and types of motility disorders are well known, and there is not much difference in interpretation of palsies in all countries. Comitant squint, however, usually is accompanied by amblyopia and in this correlation has had much attention in recent time.
The diagnosis is made by direct observation, moving capacity perimetry, coordimetry, anglemetry, and other available methods.64 Refractive squint is common, and cycloplegia is necessary. An old method with plus lenses may reveal hyperopia in less than an hour without the use of poisoning drugs, but it takes time. The correction in myopic exophoria should be full. In hyperopic esophoria all in excess of 3.00 diopter is corrected. The difference in anisometropia should not exceed 5.00 diopters. These rules are common, but there should be individual consideration of every patient.65 It may be said that every patient is an individual. One thus may sometimes neglect a routine for the sake of a patient's convenience.
Amblyopia, anomalous correspondence, and fixation have our main attention. Glasses must provide optimal functions with minimal disturbance. Glasses are not prescribed without thorough examination of the cause of squint and amblyopia.66"68 Contact lenses are not recommended except for use in rare cases of keratoconus, monocular aphakia, etc.68 Prisms are used as temporary measures or for training.
Fig. 3. The author's own Synoptophore which is smaller, lighter, and cheaper than the factory-made model (Fig. 4).
Fig. 4. Modern type of USSR-made Synoptophore available throughout the Union.
Fig. 5. The author's own Synoptophore (Fig. 3) next to the factory -made model (Fig. 4) in use in the Orel Hospital.
A century or less ago many ophthalmologists started the treatment of squint with surgery. This was a mistake, and now surgery is performed only on strict indications such as the presence of a paralytic component, a vertical squint, and in large angle strabismus unaffected by orthoptic methods.69-72 Surgery often results in insufficient or even over-effect due to undetected anomalous correspondence, changed tissues, and other reasons. In reoperation it is reasonable to involve Tenon's capsule surgically and use its action.72 The best age for surgery, if indicated, is between ages 6 to 14 71,73,74
The most important problem related to squint is amblyopia. About half a million of children in the USSR suffer from amblyopia.75 The head of the Russian Ophthalmological Society, K. Trutneva,76 in her article listed it among the principal state-important problems for all ophthalmologists and offered mass preventive measures such as those used in modern treatment of myopia.
The causes and pathogenesis of amblyopia may be reflexogenic and cortical in origin.75'77'78 They are very seldon hereditary.79 Usually, amblyopia starts with anomalous correspondence as a central sensory adjustment for a motility disorder.66 Unsteady retinal fixation is a monocular disturbance accompanying 10 to 70 per cent of amblyopias. The patient is unable to fix or hold the image in the foveal center. He soon loses attention and this leads to the sensory defect.78 Parafoveal fixation is predominant and, due to lack of differentiation in this area of the retina, amblyopia occurs. The basic theory does not differ much from conceptions of foreign ophthalmologists (Bangerter, Oppel, Cuppers, Sachsenweger). The Soviet scientists came to this conclusion on the following types of incorrect fixation: (a) parafoveal steady, (b) parafoveal unsteady, (c) paramacular steady, (d) paramacular unsteady, (e) intermittent; (f) parapapillar, (g) peripheral, and (h) in patients with no fixation, nystagmus occurs.77'80
Detection of these types is performed with the help of simple devices attached to an ophthalmoscope. There also are some clinical stationary photomicrometic and pantographic instruments with authomatics.8 ' All of them are made in the Soviet Union, and many of them are simpler and more convenient than foreign models.
The treatment of unsteady fixation resp. amblyopia is based on the theories of Bangerter and Cupper (Germany), which are popularized in the USSR after efforts of A. Roslavtsev, E. Belostotsky, et al,82'83 who constructed the first Russian Synoptophore, even with moving pictures, in I960.83
A Synoptophore was necessary and at that time many constructors and even doctors proposed their instruments resembling foreign ones, but each had some advantage. We also made two of our synoptophores in Orel in 1 960 and 1962. Both models were too simple, but they served for many years. One of them you can see in Fig. 3. As a rule all inventors in ophthalmology in the USSR meet at special conferences81"84 to report on their proposals and discuss them before a special committee. Compared to others our models were too low in quality for a general approval. Recently, a better modern type of Synoptophore has been approved for industrial production. This is now available as a convenient, universal instrument of high quality with wide distribution in all regions (Fig. 4 and 5).
There are, in addition, many original methods for diagnoses and treatment proposed by Soviet authors: correctors, localizers, mneumoscopes, and rather simple devices using impulse light, colored beam, polaroids, Heidinger phenomenon, etc. It is impossible to describe all these in this paper.77,81,84
Treatment consisting of proper optic correction, direct eye occlusion, and fusional orthoptic exercises is effective in patients with central foveal fixation. This is usually done at OPD units or even at home with the help of special recommended plays and devices: mirror stereoscope, separator, cage, and others.66,85 In patients less than six years of age, direct occlusion improves the sight in 55 per cent.86'87 A semitransparent opaque occludor prevents secondary amblyopia. Advanced stages of anomalous fixation or correspondence decrease the effect to only 17 per cent and give relapse in 38.5 per cent.86 Pleoptic treatment is needed in these patients.
The main pleoptics used for anomalous amblyopic eyes with incorrect fixation are Cuppers and Avetisov's methods. The latter is intended for special foveal stimulation with lights, either twinkling or colored. In this device, a small bulb is placed before the lens of a large ophthalmoscope through which one can constantly watch the foveal zone. The course usually consists of 25 daily stimulations. Some others alter light, color, or time, or make similar modifications. One method is that of A. Vodovozov who treats the area of anomalous fixation with a powerful beam of any color in his ophthalmochromoscope and, at the same time, stimulates the real fovea with a bluegreenish screened light.88
The results of treatment vary on conditions and even the patience of both the child and doctor. The latter has excellent effects if he is well organized, well equipped, well trained and insistent and, at the same time, loves his patients who also need interesting food for a curious mind.
After improvement of vision to 10/20 and steady foveal fixation, it becomes necessary to add binocular orthoptics.75'89 This is more difficult in patients with central functional scotomas which may be diminished with mirror-campimetry training.90 Old cases after corneal graft or cataract surgery need more time, of course.
Amblyopic children may relapse and, thus, even well-treated patients should be under constant supervision by a specialist. It is especially important to do this while the children are studying. Pupils with limited vision attend special schools and special books and methods of education91-93 are used to protect them from relapse, myopia, and other complications.
Ametropias and amblyopia affect the eyes of children and need attention of the government school administrations, local councils, teachers, medical staff, and pediatric ophthalmologists who organize and direct all preventive measures as well as examine and treat the patients. The stationary units, OPD, and orthopic clinics provide the mass measures in each regional city of the USSR. Proper examination and general treatment in myopia as well as orthoptic and pleoptic exercises in amblyopia improve the condition in most patients and prevent complications. Soviet scientists and doctors have achieved considerable theoretical and practical success in this field, mainly by using their minds and their persistence.
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