Optic nerve hypoplasia in newborns. Hypoplasia of the nerve of the eye Congenital hypoplasia of the macula of both eyes

22-11-2013, 01:27

Description

- a common congenital polyetiological non-progressive anomaly, caused by a decrease in the number of axons of the affected nerve with the normal development of supporting tissue. In China, patients with optic nerve hypoplasia account for 5,9 % of the total number of blind people aged from 5 to 15 years.

Pathogenesis. Until recently, it was believed that optic nerve hypoplasia develops as a result of impaired differentiation of retinal ganglion cells at the embryonic stage 13-15 mm, which corresponds to 4-6 weeks of gestation. However, this hypothesis did not explain the phenomenon of the frequent combination of optic nerve hypoplasia with brain malformations and was not confirmed by some histological findings. In particular, in patients with optic nerve hypoplasia, amacrine and horizontal cells, which have common precursors with ganglion cells, remain intact.

It is possible that in some cases, optic nerve hypoplasia is the result of the culmination of axonal regression during apoptosis during the period from 16 th 31 th week of gestation or the outcome of retrograde degeneration during encephaloclastic processes leading to: the formation of brain defects (porencephaly, hydranencephaly, etc.) and causing damage to the pregeniculate visual pathways.

The frequent combination of cerebral hemispheric anomalies with optic nerve hypoplasia suggests that its development is caused by a violation of the mechanisms of regulation of intrauterine migration - both neurons of the cerebral hemispheres and axons of retinal ganglion cells. Optic nerve hypoplasia may be associated with suprasellar tumors, such as teratoma. Probably, in the prenatal period, when certain parts of the optic pathway are compressed by a neoplasm, the process of normal development of the optic nerve is disrupted.

Etiology. Teratogenic effects can aggravate normal processes occurring in the prenatal period, such as apoptosis, leading to the development of optic nerve hypoplasia. In experiments on mice and in examining children born to mothers at “high” risk, it was shown that taking cocaine or alcohol during pregnancy leads to a significant increase in the incidence of optic nerve hypoplasia in the offspring.

Optic nerve hypoplasia is detected in 50 % newborns with fetal alcohol syndrome. Risk factors include the young age of mothers, the presence of insulin-dependent diabetes mellitus, smoking and the use of certain pharmaceuticals (phenobarbital, LSD, quinine, depakine, antidepressants) during pregnancy, and prematurity.

Cases of the development of optic nerve hypoplasia in children who have had intrauterine herpetic or cytomegalovirus infection have been described. No regular chromosomal defects were identified in patients with isolated optic nerve hypoplasia. Meanwhile, Y. Hackenbrach et al. (1975) reported on 5 patients with bilateral optic nerve hypoplasia from different generations of the same family, suggesting an autosomal dominant mode of inheritance. A. J. Churchill et al. (2000) found a PAX6 gene mutation at 11p13 in a father and son with ocular changes including aniridia, early-onset cataracts, and optic nerve hypoplasia. Mutation of the PAX6 gene at the 11p13 locus leads to the development of aniridia. It is important to note that the genetic defect in my son was verified prenatally - during amniocentesis at 16 th week of gestation.

Histological studies. Morphological studies of eyes with optic nerve hypoplasia revealed a decrease in the number of retinal ganglion cells. Horizontal and amacrine cells appear normal and their number does not decrease. The area surrounding the reduced optic disc is covered by retinal pigment epithelium, which creates an ophthalmoscopic “double ring” effect. In a histological study of hypoplastic optic nerves of fetuses extracted from rats fed a diet containing 5 % alcohol, a significant decrease in the cross-section of the affected nerve was found.

Electron microscopy revealed changes in the neuropil, a decrease in the number of astroblasts and the presence of pyknotic nuclei in some of them, atrophy and degeneration of optic nerve axons, ultrastructural disorders of the myelin sheaths, astrocytes and oligodendrocytes. Signs of extraisluteal edema were found in the layers of the retina (outer nuclear, nerve fibers and ganglion cells), a decrease in the number and size of axons, axonal and periaxonal edema (between the axolemma and the nerve sheath), and thinning of myelin. K. Sawada et al. (2002) revealed selective loss of small-diameter myelinated axons in rabbits born to dams exposed to ethanol during pregnancy between days 10 and 21 of gestation.

Clinical manifestations. The first clinical description of optic nerve hypoplasia belongs to W. Newman (1864). Optic nerve hypoplasia varies in severity and can be either unilateral or bilateral. In infants with severe forms of the disease, parents notice strabismus, nystagmus and lack of adequate visual orientation in the child already at age 2-3 MSS. Nystagmus and/or strabismus are determined in 86- 92 % children with optic nerve hypoplasia. With unilateral or asymmetrical lesions, deviation of the eye with more pronounced changes in the disc is noted. Often, patients with optic nerve hypoplasia have an afferent pupillary defect.

Ophthalmoscopic manifestations of optic nerve hypoplasia:

Damage to the optic nerve can be isolated, but is often combined with ametropia (myopia, myopic or hyperopic astigmatism) and other eye anomalies (microphthalmos, congenital cataracts, aniridia, primary persistent hyperplastic vitreous body, etc.).

Optic nerve hypoplasia in systemic lesions. Brain malformations are detected in 50 % children with optic nerve hypoplasia. Cases of a combination of optic nerve hypoplasia with hemispheric migration anomalies (schizencephaly or cortical hegerotopia), as well as with intrauterine and/or perinatal damage of hypoxic-ischemic, toxic-dismetabolic or infectious etiology (periventricular leukomalacia, cortical and subcortical encephalomalacia) have been described. Hemispheric abnormalities in newborns with optic nerve hypoplasia can be considered an unfavorable prognostic criterion indicating future neurological abnormalities. Neurological symptoms are observed in 20 % patients with optic nerve hypoplasia.

In 1956, G. sk-Morsier described the so-called septo-optic dysplasia, which includes the following triad of symptoms: optic nerve hypoplasia, agenesis or thinning of the corpus callosum and septum pellucidum (Fig. 13.4).

Septo-optic dysplasia is often combined with pituitary insufficiency (which can manifest as severe growth retardation) and neurological disorders (convulsions, paresis, etc.). It was found that septo-optic dysplasia develops more often in children born to mothers aged 20 years and younger.

Endocrine dysfunctions are determined in 27-43 % children with optic nerve hypoplasia. Posterior ectopia of the pituitary gland, which is essentially a pathognomonic sign of hormone deficiency in its anterior lobe, is detected by MRI in approximately 15 % patients with optic nerve hypoplasia. Growth hormone deficiency is the most common endocrine disorder associated with optic nerve hypoplasia. Other endocrine disorders are less common: hypothyroidism, panhypopituitarism, diabetes insipidus, hyperprolactinemia.

Optic nerve hypoplasia is a symptom that is important for the differential diagnosis of certain malformations: Patau syndromes (trisomy 13 th chromosome), Alert, Warburg, Meckel-Gruber, Zellweger's disease or cerebrohepatorenal syndrome. Detection of optic nerve hypoplasia in patients with Warburg syndrome (autosomal recessive oculocerebral syndrome) is a diagnostic “key” to distinguish this disease from common defects of neural tube development.

Cases of unilateral and bilateral optic nerve hypoplasia have been described in children with frontonasal dysplasia and basal encephalocele, as well as in patients with epidermal nevus of Jadassohn. D.A. Thompson et al. (1999) reported a patient with bilateral optic nerve hypoplasia, achiasmia (non-crossed retinal fiber syndrome), cleft lip and hard palate, nasosphenovdal encephalocele, agenesis of the corpus callosum and absent falx big brain. The combination of bilateral optic nerve hypoplasia with achiasmia, absence of optic tracts and focal polymicrogyria of the left perisylvian region in a 5-month-old infant was described by K. Waheed et al. (2002).

Optic nerve hypoplasia occurs in 30-57 % of patients with Eicardi syndrome, which is characterized by agenesis of the corpus callosum, myoclonic seizures, mental retardation and lacunar chorioretinal lesions.

Visual functions. Visual acuity with optic nerve hypoplasia varies from 1,0 to “absence of veto sensation.”

Visual field impairments detected in patients with optic nerve hypoplasia are quite diverse: local central and/or peripheral loss, hemianoptic defects, concentric narrowing.

Inferonasal and inferior colliculose defects in the visual field have been described in children with superior segmental optic nerve hypoplasia born to mothers suffering from insulin-dependent diabetes mellitus. Optical coherence tomography in these patients reveals segmental thinning of the retinal nerve fiber layer and (in some cases) abnormal enlargement of the retinal pigment epithelium-choroid complex over the edge of the lamina cribrosa.

The polymorphism of visual field defects is explained by the variety of morphological disorders in patients with optic nerve hypoplasia. Not only the disc and optic nerve can be hypoplastic, but also the chiasm, optic tract, and any segment of the retrogenic visual pathways, such as optic radiation. Hypoplasia of optic radiation was described by M. Brodsky et al. (1997) in a child with congenital peripapillary staphyloma, atypical hemimegacephaly and seborrheic nevus of Jadassohn. In patients with combined hypoplasia of the optic nerve, chiasm and/or retrogenic visual pathways, hemianoptic or quadrantoptic visual field defects are determined. Violations color vision, as a rule, is not detected.

Electrophysiological studies. ERG with optic nerve hypoplasia usually remains normal, at the same time G.Cibis and K.Fitzgerald (1994) established a decrease in ERG amplitude in 42 % patients with optic nerve hypoplasia. The authors explained the detected changes by transsynaptic degeneration of structures lying distal to ganglion cells, which, however, was not convincingly argued.

The electrooculogram does not change in isolated optic nerve hypoplasia. The most informative test for assessing visual functions in children with optic nerve hypoplasia is recording of visual evoked potentials (VEP). The amplitude and latency values ​​of the main positive component P100 of VEP in optic nerve hypoplasia correlate with the size of the optic nerve head. This dependence is probably due to the number of neurons involved in generating responses. With a diameter of the optic nerve head from 0,1 to 0,25 RD (see Fig. 13.1) VEPs, as a rule, are not registered (Fig. 13.5). Visual acuity in these children usually fluctuates within the range of “O - correct light projection.”

In cases where the disk diameter is 0.3-0.5 RD (see Fig. 13.2), VEPs are recorded in response to a flash stimulus or reverse patterns with cell sizes 220-55" . The latency of a P100 VEP is significantly increased, and the amplitude is reduced compared to the age norm (see Fig. 13.5). Visual acuity in these children varies from 0,005 to 0,04 . In patients whose disc diameter exceeds 0.6 RD (see Fig. 13.3), flash stimulus and patterns with cell sizes of 110-7" are recorded (Fig. 13.6). In these patients, the latency is increased and the amplitude of the RSO pattern component is reduced -VEP, and visual acuity is 0,03- 1,0 . The VEP recording method is useful for determining the severity of visual impairment and predicting functional outcomes in young children with optic nerve hypoplasia.

X-ray studies. In patients with optic nerve hypoplasia, a decrease in the size of the optic canal is often determined by canal x-ray or axial x-ray tomography, but no direct correlation has been found between the severity of optic nerve damage and canal diameter. This is not surprising, since even in healthy people there is a possible difference in the parameters of the visual channel between the right and left orbits, sometimes reaching 20% . Currently, the use of routine x-ray methods for diagnostic purposes in patients with suspected optic nerve hypoplasia has lost relevance due to the widespread introduction of x-rays into clinical practice. computed tomography, magnetic resonance imaging and neurosonography (NSG).

Neuroradiological and ultrasound studies. CT scan of the orbit and brain in some cases can reveal thinning of the optic nerve in its orbital part (Fig. 13.7), as well as a decrease in the diameter of the optic opening of the orbit, hemispheric migration anomalies, periventricular leukomalacia, encephalomalacia, anomalies of midline brain structures (underdevelopment or agenesis corpus callosum, absence of a transparent septum), etc.

NSG has comparable resolution capabilities to CT and MRI when examining the brain in children under 1 year of age. NSG allows us to identify changes in the central nervous system combined with optic nerve hypoplasia, in particular malformations of the brain [holoprosenyphaly (Fig. 13.8),

agenesis of the corpus callosum and septum pellucidum (see Fig. 13.4), agyria, schizencephaly (Fig. 13.9),

hydranencephaly (Fig. 13.10), etc.]

and pathology caused by hypoxic-ischemic disorders [periventricular leukomalacia (Fig. 13.11), etc.], hemorrhagic and inflammatory intracranial lesions in young children with an open anterior fontanel. NSG has a number of advantages over CG and MRI: the duration of the study, the need for contrast, the absence of image disintegration during movement (anesthesia is not required), the absence of exposure to ionizing radiation, portability and the relative cheapness of the equipment.

NSG is indicated for all infants with optic nerve hypoplasia, and children with hypoglycemia, especially those born to mothers under the age of 20 years, should undergo MRI to exclude possible neuroendocrine dysfunctions.

MRI is an optimal non-invasive diagnostic method in terms of its resolution capabilities, as it allows not only to establish the correct diagnosis in controversial cases, but also to carry out a rather complex differential diagnosis with various neuroendocrine diseases, often combined with optic nerve hypoplasia.

When using coronal and sagittal sections, it is possible to identify a decrease in the diameter of the intraorbital and intracranial parts of the optic nerve, diffuse thinning or absence of the chiasm in a bilateral process (chiasmatic hypoplasia or achiasmia), hypoplasia of the optic tract, hypoplasia or posterior ectopia of the pituitary gland, and abnormalities of the structures of the midline of the brain.

Detection of infundibular hypoplasia or posterior ectopia of the pituitary gland in children with optic nerve hypoplasia during MRI is a prognostic criterion indicating the development of endocrine insufficiency in the future.

According to neuroradiological studies, agenesis of the corpus callosum and/or septum pellucidum is determined in 46-53 % patients with optic nerve hypoplasia, other malformations of the central nervous system - in 12- 45 % cases.

Differential diagnosis. Despite the characteristic ophthalmoscopic picture, the correct diagnosis in patients with optic nerve hypoplasia is often established only at an older age. Problems with ophthalmoscopic diagnosis in infants are associated, as a rule, with their active behavior during examination. Patients are often observed for a long time with the diagnosis of “optic nerve atrophy” Differential diagnosis Hypoplasia and atrophy of the optic nerve usually causes difficulties in bilateral lesions and is based only on ophthalmoscopy data. In patients with optic nerve hypoplasia, the disc may have a white or gray color, but it is always reduced in size. Additional signs indicating optic nerve hypoplasia are the “double ring” symptom and corkscrew tortuosity of the vessels.

Difficulties in interpreting the ophthalmoscopic picture may arise when examining patients with high hyperopia, when the examination creates the false impression that the optic disc has a smaller diameter.

In difficult cases, auxiliary diagnostic methods are used:

• calculation of the ratio of the disc-macula distance to the disc diameter (normally< 3) при обычной фоторегистрации;
• measuring disk parameters using a computer disk analyzer;
• photographing the fundus in red-free light with high resolution, allowing to determine the defect of the nerve fiber layer;
• study of the thickness of the nerve fiber layer using optical coherence tomography, which is especially informative if there are corresponding changes in the field of view.

Hypoplasia of the optic nerve must be differentiated from its aplasia. These conditions have clear clinical differences: with optic seal hypoplasia, even if the optic seal disc is practically indistinguishable, the central retinal vessels are always identified, having a normal caliber and a corkscrew-like course.

If optic nerve hypoplasia is detected in a young child, the ophthalmologist should rule out possible subclinical endocrine or neurological disorders as quickly as possible.

A thorough examination using immunobiochemical and neuroradiological methods will make it possible to diagnose neuroendocrine disorders even before the clinical manifestation of the disease and prescribe adequate therapy to the child, which will prevent the development of irreversible complications. In these situations, the use of MRI helps to obtain information necessary for differential diagnosis and neurosomatic prognosis. A history of neonatal jaundice in infants with optic nerve hypoplasia suggests secondary hypothyroidism, while neonatal hypoglycemia or paroxysms indicate panhypopituitarism. Therefore, MRI should be used to rule out secondary neonatal hypothyroidism in infants with optic nerve hypoplasia. Due to the obvious difficulty in assessing normal growth hormone levels, most patients with optic nerve hypoplasia should be monitored by a pediatrician. In case of growth retardation, biochemical studies are necessary to confirm the diagnosis. Children with optic nerve hypoplasia, hypoglycemia, neonatal jaundice, and posterior pituitary ectopia on MRI usually have anterior pituitary hormonal deficiency. Such patients are indicated for a detailed endocrinological examination.

Agenesis of the septum pellucidum and/or corpus callosum detected by NSG, CT or MRI is not a reliable sign of neurological disorders or hormonal deficiency. It is possible to predict the appearance of neurological abnormalities in infants with optic nerve hypoplasia and hypo- or agenesis of the corpus callosum or septum pellucida only when these malformations are combined with hemispheric migration anomalies.

Treatment. Some authors are skeptical about the treatment of patients with optic nerve hypoplasia. Our experience shows that rehabilitation attempts made at an early age in children with optic nerve hypoplasia, in some cases, lead to positive results. In addition, some development of visual functions in children of the first year of life with optic nerve hypoplasia may be due to the ongoing maturation of pre- and postgenic visual pathways and cortical centers. It is known that to 6 -at one month of age, the volume of the human lateral geniculate body increases in 2 times, up to 4 In the postnatal period, the number of spines on the dendrites and soma of neurons increases. Synaptogenesis in the field 17 according to Brodmann reaches a peak at 8 In the 1st month of life, there is a simultaneous increase in the width of the cortex in all visual fields. The described processes, characteristic of healthy infants, also occur in children with optic nerve hypoplasia. Due to plasticity nervous system in young children, treatment carried out during this period allows achieving better functional results.

Rehabilitation of children with optic nerve hypoplasia primarily involves eliminating the fatal effect of visual deprivation on the maturing visual system. In this regard, functional rehabilitation of children with optic nerve hypoplasia primarily includes measures to prevent the development of amblyopia (refractive, dysbinocular, etc.) and its treatment. Children with optic nerve hypoplasia should be prescribed spectacle or contact correction of ametropia, dosed occlusion of the better-seeing eye in case of unilateral or asymmetrical lesions, laser pleoptics and transcutaneous electrical stimulation of the optic nerve as early as possible. Surgical treatment of strabismus is possible for a cosmetic or, in the presence of high visual acuity, a functional purpose (development of binocular vision). At the same time, it is necessary to correct somatic and neuroendocrine disorders.

Optic nerve hypoplasia in young children: diagnosis, clinical significance

THEM. Mosin, V.F. Smirnov, E.V. Yaroslavtseva, N.V. Slavinskaya, EL. Neudakhina, I.G. Balayan

Optic nerve hypoplasia in infants: diagnostics, clinical significance

I.M. Mosin, V.F. Smirnov, E.V. Yaroslavtseva, N.V. Slavinskaya, E.A. Neudakhina, I.G. Balayan

Russian Medical Academy of Postgraduate Education, Moscow;

Tushino Children's Clinical Hospital, Moscow; Moscow Research Institute of Pediatrics and Pediatric Surgery

In 32 infants aged from 2 weeks to 11 months with optic nerve hypoplasia and 40 healthy children, optic disc biometry was performed using a hand-held digital fundus camera, as well as neurosonography and magnetic resonance imaging of the brain. More than 2/3 of infants with optic nerve hypoplasia have structural brain abnormalities. In healthy children under 1 year of age, the vertical and horizontal diameters of the excavation were 0.31 + 0.06 and 0.32 + 0.07 of the disc diameter, respectively, the ratio of the areas of the excavation and the disc was 0.10 + 0.04, the ratio of the foveal distance - disk to disk diameter - 2.38+0.26. In children with optic nerve hypoplasia, the ratio of the foveal-disc distance to the disc diameter was 4.59+1.67 (¿><0,001). Измерение отношения расстояние фовеола - диск к диаметру диска - простой метод диагностики гипоплазии зрительного нерва; диагноз устанавливается, если данный коэффициент превышает 2,9. Чувствительность метода - 96,9%.

Key words: newborns, children of the first year of life, optic nerve hypoplasia, optic nerve hypoplasia, large cup syndrome.

Biometry of the optic disk by means of a manual digital fundus chamber, as well as neurosonography and brain magnetic resonance imaging were performed in 32 babies aged 2 weeks to 11 months who had optic nerve hypoplasia and in 40 healthy infants. Brain structural anomalies were detected in more than two thirds of babies with optic nerve hypoplasia. In healthy babies under 1 year of age, the vertical and horizontal diameters of excavation were 0.31+0.06 WP and 0.32+0.07 WP, respectively; the excavation/disk area ratio was 0.10+0.04; the foveola-disk distance/disk diameter ratio was 2.38+0.26. In infants with optic nerve hypoplasia, the foveola-disk distance/disk diameter ratio was 4.59+1.67 (p<0,001). Measurement of the foveola-disk distance/disk diameter is a simple method for diagnosing optic nerve hypoplasia; the diagnosis is established if this ratio is greater than 2,9. The sensitivity of the method is 96,9%.

Key works: neonatal infants, babies of the first year of life, optic nerve hypoplasia, large cup syndrome.

In economically developed countries, optic nerve hypoplasia accounts for about 5% of the causes of low vision and blindness in children. In the last decade, the number of children with optic nerve hypoplasia has increased significantly due to advances in perinatal nursing of premature and mature infants with pathology of the central nervous system caused by perinatal hypoxic-ischemic and infectious lesions. Diagnosis in young children, as a rule, causes difficulties due to the impossibility of accurately assessing the parameters of the disc visually.

th nerve during ophthalmological examination of infants characterized by restless behavior, and difficulties associated with the interpretation of the ophthalmoscopic picture in the first months of life. Meanwhile, identifying optic nerve hypoplasia in the first days of a child’s life allows one to quickly determine the optimal diagnostic strategy for children with multisystem pathology, preventing the development of irreversible complications or even death as a consequence of late diagnosis of endocrine or neurological disorders.

The introduction of modern digital fundus imaging technologies into clinical practice increases the possibilities of ophthalmoscopic diagnosis in cases where the use of routine methods does not allow effective assessment of the parameters of the structures of the posterior pole of the eye. Carrying out quick biometrics of the visual disc

nerve when using digital imaging methods during the examination of infants, taking into account the ophthalmoscopic features of the neonatal period, would reduce the likelihood of diagnostic errors when verifying optic nerve anomalies. In this regard, this study had the following objectives:

Using a hand-held digital fundus camera, study the ophthalmoscopic parameters of the optic nerve head in healthy children and infants with various forms of optic nerve hypoplasia;

Using radiological diagnostic methods to study the state of brain structures in patients with verified optic nerve hypoplasia.

Characteristics of children and research methods

The results of ophthalmoscopy were analyzed in 40 healthy children aged from 2 weeks to 11 months and in 32 children of the same age with optic nerve hypoplasia of various etiologies.

The diagnosis was established on the basis of a neuro-ophthalmological examination, including direct and reverse ophthalmoscopy, recording of an electroretinogram and visual evoked potentials according to the method described previously. Data from the perinatal history and examination were taken into account (the course of pregnancy in the mother, the presence of neonatal jaundice, hypoglycemia, seizures, disorders of the immune status, etc.).

All children had fundus photographs taken while they were awake using a hand-held digital camera “Nidek NM-200”. Subsequent processing of the images was carried out using the supplied commercial software for image analysis NAVIS (Nidek, version 2005). When analyzing the optic disc image, the following parameters were measured:

The ratio of the vertical and horizontal diameters of the excavation and the optic nerve head;

The ratio of the distance from the foveola to the edge of the optic disc to the diameter of the disc;

Ratio of excavation area to disc area.

The specified coefficients were chosen to solve the stated diagnostic problems because in the NAVIS software all disk sizes are measured in pixels. To measure the above parameters in the software, the cursor was drawn around the contours of the optic nerve head and excavation, highlighting them in white and blue, respectively. Additional

A straight line was carefully drawn from the center of the foveal or foveal reflex to the temporal edge of the disc in the equator (Fig. 1).

All children underwent neurosonography on a Volus-on-730 ultrasound diagnostic device (USA) using standard sector and micro-convex sensors with a scanning frequency of 5-7 MHz. Children with optic nerve hypoplasia underwent magnetic resonance imaging of the brain using a Signa tomograph (General Electric, USA) using 5-10 mm sections.

A control group of 40 healthy children was formed based on certain criteria: uncomplicated medical history, delivery at term, birth weight 2900 g or more, Apgar score of at least 8 points, absence of ophthalmological and systemic pathology, as well as changes in neurosonography. Excel was used for statistical processing of the results.

RESULTS

In healthy children under 1 year of age, when measuring the parameters of the optic nerve head, the following results were established:

The vertical diameter of the excavation is 0.31±0.06 of the disk diameter;

The horizontal diameter of the excavation is 0.32±0.07 of the disk diameter;

The ratio of excavation and disk areas is 0.10±0.04;

The ratio of the foveal-disc distance to the disc diameter is 2.38±0.26.

Ophthalmoscopy in all children with optic nerve hypoplasia revealed varying degrees of reduction of the optic nerve head, absence

Rice. 1. Fundus of a healthy baby aged 2 months.

Optic disc image processing in NAVIS software. The outlines of the disc and excavation are highlighted in white and black, respectively. The boundaries of the disc and scleral ring coincide. The white horizontal line is a segment of the foveola - the edge of the disc.

foveal reflexes. In a number of cases, pronounced decoloration of the disc, a symptom of a “double ring” formed by two pigment rims located along the perimeter of the reduced disc and the normal scleral ring, and corkscrew-shaped tortuosity of the vessels were noted (Fig. 2). The vertical and horizontal diameters of the disc in children with optic nerve hypoplasia varied from 0.41 to 0.88 and from 0.32 to 0.91 of the disc diameter compared with the vertical and horizontal diameters of the normal scleral ring determined on the photograph, averaging 0. 75±0.17 and 0.70±0.17 disk diameters, respectively (^<0,01).

In children with optic nerve hypoplasia, the ratio of the foveal-disc distance to the disc diameter in all cases exceeded the age standard, varying from 2.89 to 9.31 (Fig. 3). On average, the ratio of the foveal-disc distance to the disc diameter in children with optic nerve hypoplasia in

in our study was 4.59±1.67, which significantly exceeded the parameters of the control group (^<0,01). Чувствительность описанного метода оценки диска зрительного нерва составила в нашем исследовании 96,9%.

Neurosonography and/or magnetic resonance imaging revealed pathological changes in the brain in 22 of 32 children with optic nerve hypoplasia. 17 of them had combined brain changes. Detected disorders included: hypo- or agenesis of the corpus callosum (in 12 children), agenesis of the septum pellucida (in 7), periventricular leukomalacia (in 7), porencephalic or arachnoid cysts (in 3; Fig. 4), posterior ectopia pituitary gland (in 3), schizencephaly (in 3), heterotopia of gray matter to white (in 2), hydranencephaly (in 1), Dandy-Walker syndrome (in 1), colpocephaly (in 1), holoprosencephaly (in 1; see. Fig. 2, b, c).

Rice. 2. Fundus (a) and neurosonograms (b, c) of a one-month-old child with optic nerve hypoplasia and holoprosencephaly.

a - the optic nerve disc is reduced in diameter to 0.55 of the disc diameter, decolorized. The vessels are corkscrew-shaped. Symptom of “double ring” (explanation in the text).

b - neurosonogram (coronary scan at the level of the foramina of Monroe and the third ventricle): holoprosencephaly (hemilobar form); the lateral ventricles are fused with each other in the anterior sections.

c - neurosonogram (coronary scanning through the posterior sections of the lateral ventricles): holoprosencephaly; partial separation of the visual hillocks from each other; The brain substance is presented in the form of a mantle-like zone along the periphery of the lateral ventricles.

Rice. 3. Fundus of a patient with optic nerve hypoplasia.

Optic disc image processing in NAVIS software. The outlines of the disc and excavation are highlighted in white and black, respectively. The horizontal size of the disc is reduced to 0.73 disc diameter. Pigmented scleral ring of normal size. The white horizontal line is a segment of the foveola - the edge of the disc. The ratio of the distance between the foveola and the edge of the disc to the diameter of the disc is 3.22.

Analysis of anamnesis data showed that long-term (more than 2 weeks) neonatal jaundice was observed in 5 of 32 patients, hypoglycemia - in 4, neurological symptoms (paroxysms, spastic diplegia, muscular dystonia, etc.) - in 18. These disorders were observed only in children with optic nerve hypoplasia and structural changes in the brain verified by neurosonography and/or magnetic resonance imaging.

DISCUSSION

Detection of optic nerve hypoplasia in children in the first months of life plays an important role in the early diagnosis of various systemic somatic and neuroendocrine diseases (neonatal cholestasis, de Morsier septo-optic dysplasia, periventricular leukomalacia, etc.). Detection of optic nerve hypoplasia is a key point in differential diagnosis during genetic counseling, for example, in the clinical verification of Patau, Apert, Meckel-Gruber syndromes, and Zellweger disease. Meanwhile, adequate assessment of optic disc parameters in young children can cause significant difficulties due to their restless behavior. It is even more difficult to determine the size of the optic disc in infants with nystagmus, which is often combined with various pathologies of the eyes and central nervous system.

The optic disc in healthy newborns appears gray or pale, physiological excavation and the foveal reflex are absent, and the vessels have a straight course. Excavation of the optic disc, the diameter of which does not exceed 0.3 the diameter of the disc, is determined only in 7.5% of healthy infants under 6 months of age who do not have abnormalities in neurosonography. M.V. Drozdova discovered excavation of the optic disc in 25% of newborns, and T.V. Birich and V.N. Peretitskaya - 28%.

Rice. 4. Arachnoid cyst of the brain in a child with hemianoptic hypoplasia of the optic nerve.

Magnetic resonance imaging (T1 mode): axial (a) and coronal (b) sections. A giant arachnoid cyst of the left hemisphere, causing displacement of the midline structures of the brain and involving the optic radiation. The medial sections of the left occipital lobe in the projection of the striate cortex are preserved.

But the authors did not evaluate its diameter, did not analyze the pre- and perinatal status of the examined infants and, unfortunately, did not have the opportunity to assess the state of their brain, including the postgeniculate visual pathways, using radiological diagnostic methods. Therefore, it cannot be ruled out that some of the newborns they examined had structural changes in the brain.

The method described above for measuring the ratio of the foveal-disc distance to the disc diameter during digital fundus photography is a simple and reliable way to diagnose optic nerve hypoplasia, including its various subclinical forms - horizontal sectoral hypoplasia, hemianoptic hypoplasia. In healthy children, the ratio (coefficient) of the foveal-disc distance to the disc diameter is 2.38+0.26. A coefficient exceeding 2.9 (standard + 2a) indicates optic nerve hypoplasia. A study using a hand-held digital camera (for example, the Noek NM-200 device), including image analysis in software, takes about 5 minutes and does not require anesthesia, which allows the technique to be used for studying children from the first days of life. The small dimensions of the manual fundus camera allow for research in children

even in intensive care units, without removing them from the incubator.

To diagnose another form of optic nerve hypoplasia - extended excavation syndrome (Fig. 5, a), often observed in infants with periventricular leukomalacia (Fig. 5, b), it is necessary to compare at least three parameters with the norm: the horizontal diameter of the excavation (c The norm for children under the age of 12 months is 0.32 + 0.07 disc diameter), the ratio of the areas of excavation and disc (the norm is 0.10 + 0.04) and the ratio of the foveal-disc distance to the disc diameter (in healthy children - 2. 38+0.26). The last coefficient must be taken into account because a significant increase in excavation can be observed in children with congenital enlargement of the optic nerve head (megalopapilla) and coloboma-like optic nerve dysplasia. If the coefficient is less than 1.86 (standard -2a), then we can assume that the child has megalopapilla. When differentially diagnosing megalopapilla and extended excavation syndrome, it is necessary to take into account the ratio of the areas of excavation and the optic nerve head. In healthy children and patients with congenital enlargement of the optic nerve head (megalopapilla), this coefficient is 0.10+0.04. In patients with the syndrome

Rice. 5. Fundus (a) and neurosonogram (b) of a child with extended excavation syndrome (clinical form of optic nerve hypoplasia) and periventricular leukomalacia.

a - the optic disc has a normal diameter. The excavation is increased to 0.78 of the vertical disk diameter, and to 0.84 of the horizontal disk diameter. The foveal reflex is absent.

b - neurosonogram (coronal section): multiple periventricular cysts, moderate expansion of the lateral ventricles at the level of the anterior horns.

extended excavation, the horizontal diameter of the excavation increases to 0.611+0.026 of the disc diameter, and the ratio of the areas of the excavation to the optic nerve head increases to 0.35+0.123 (^<0,001) , что свидетельствует о значительном увеличении площади экскавации и уменьшении площади нейроретинального кольца. Это связано с частичной потерей аксонов зрительного нерва вследствие транссинаптической нейро-нальной дегенерации .

Knowledge of the normal parameters of optic disc excavation in children of the first year of life is also important for the early diagnosis of congenital glaucoma. It is known that with glaucoma there is a progressive increase in the vertical size of the excavation, while in children with extended excavation syndrome its increase is determined mainly horizontally in the temporal direction.

In more than 2/3 of children with optic nerve hypoplasia, pathological changes in the brain were detected using radiation diagnostic methods. This does not contradict the results of previously published neuroradiological studies, according to which agenesis of the corpus callosum and/or septum pellucidum occurs in 46-53% of patients with optic nerve hypoplasia, other brain malformations - in 12-45% of patients. It should be noted the high frequency of detection of cystic periventricular leukomalacia in the group of children with optic nerve hypoplasia we examined - in 7 out of 32 patients. This indicates that perinatal hypoxic-ischemic lesions of the periventricular white matter of the brain, much more often than previously thought, lead to disruptions in the normal development of pregeniculate visual pathways and the formation of optic nerve hypoplasia.

Identification of certain abnormalities of the optic nerve in children with lesions of the central nervous system allows us to determine the period of damage to the fetus. L. Jacobson et al. It is believed that with lesions of the periventricular white matter of the brain that developed before 28 weeks of gestation, patients develop “classical” optic nerve hypoplasia, manifested by a decrease in its diameter. If damage to the periventricular white matter of the brain occurs after 28 weeks of gestation, then children develop extended excavation syndrome. Meanwhile, E. McLoone et al. when analyzing the results of neurosonography and ophthalmoscopic changes in 109 children with hypoxic-ischemic lesions of the periventricular

white matter of the brain, which developed in the period from 24 to 33 weeks of gestation, did not find such a pattern. In patients with hydran encephaly, both clinical variants of the optic nerve anomaly often occur - “classical” optic nerve hypoplasia and extended excavation syndrome. It is known that hydran encephaly can develop during intrauterine viral or toxoplasmosis infection of the fetus in the period from 9 to 28 weeks of pregnancy due to cerebral infarction as a result of occlusion of the supracuneiform sections of the internal carotid arteries. These anomalies are often combined in one patient, when extended excavation syndrome is observed in one eye, and “classic” optic nerve hypoplasia in the other. S. Shssheg et al. Histological studies have established that normally the growth of the optic nerve head and its more proximal parts is completed by only 50% by 20 weeks of gestation, and by 75% by 38-40 weeks of gestation. Thus, relying only on the results of ophthalmoscopy, it is impossible to determine the moment of perinatal damage, since the mechanisms that induce the development of various forms of optic nerve hypoplasia with damage to the periventricular white matter of the brain remain unclear.

Considering the high frequency of neuroradiological abnormalities in infants with optic nerve hypoplasia, it is advisable for ophthalmologists and neonatologists to prescribe neurosonography to all children with this eye anomaly. Children in whom optic nerve hypoplasia is combined with prolonged neonatal jaundice, hypoglycemia and/or convulsive paroxysms should undergo ultrasound examination of the abdominal organs and kidneys, as well as magnetic resonance imaging to exclude pathology of the central nervous system, in particular pituitary hypoplasia.

Measuring the ratio of the foveal-disc distance to the disc diameter using a hand-held digital fundus camera is a simple and sensitive (96.9%) method for diagnosing various, including subclinical, forms of optic nerve hypoplasia (horizontal sectoral and hemianoptic forms of hypoplasia, syndrome extended excavation). In healthy children, the ratio of the foveal-disc distance to the disc diameter is 2.38+0.26. If this coefficient exceeds 2.9 (standard +2o), then the patient has optic nerve hypoplasia.

More than 2/3 of infants with optic nerve hypoplasia have structural brain abnormalities. Children with optic nerve hypoplasia combined with neonatal jaundice, hypoglycemia or neurological symptoms are advised to undergo a comprehensive examination.

testing using radiation diagnostic methods (neurosonography and magnetic resonance imaging, ultrasound examination of the abdominal organs) for the early detection of somatic and neuroendocrine dysfunctions.

LITERATURE

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2. Good W.V., Jan J.E., Burden S.K et al. Recent advances in cortical visual impairment. Dev Med Child Neurol 2001; 43:1:56-60.

3. Gronqvist S., Flodmark O., Tornqvist K. et al. Association beetween visual impairment and functional and morphological cerebral abnormalities in full-term children. Acta Ophthalmol Scand 2001; 79:2:140-146.

4. Birich T.V., Peretitskaya V.N. Changes in the fundus of the eye in newborns during normal and pathological childbirth. Minsk: Belarus 1975; 176.

5. Khukhrina L.P. Some data on the state of the visual organ of newborns. Bulletin oftalmol 1968; 5: 57-61.

6. Filchikova L.I., Mosin I.M., Kryukovskikh O.N. and others. Visual evoked potentials of young children in normal conditions and with optic nerve hypoplasia. Vestn ophthalmol 1994; 3:29-32.

7. McLoone E, O'Keefe M, Donoghue V. et al. RetCam image analysis of optic disc morphology in premature infants and its relation to ischemic brain injury. Br J Ophthalmol 2006; 90: 4: 465-471.

8. Yannuzzi L.A., Ober M.D., Slakter J.S. et al. Ophthalmic fundus imaging: today and beyond. Amer J Ophthalmol 2004; 137:3:511-524.

9. Mosin I.M., Moshetova L.K., Slavinskaya N.V. and others. Ophthalmological symptoms in children with periventricular leukomalacia. Vestn ophthalmol 2005; 121:2:13-18.

10. Mosin I.M., Moshetova L.K., Vasilyeva O.Yu. and others. Ophthalmological disorders in children with periventricular leukomalacia. Pediatrics 2005; 1: 26-33.

11. Brodsky M.C. Periventricular leukomalatia: an intracranial cause of pseudoglaucomatous cupping. Arch Ophthalmol 2001; 119:4:626-627.

12. Fahnehjelm K.T., Fischler B., Jacobson L, Nemeth A. Optic nerve hypoplasia in cholestatic infants: a multiple case study. Acta Ophthalmol Scand 2003; 81:2:130-137.

13. Jacobson L., Hard A.L., Svensson E. et al. Optic disc morphology may reveal timing of insult in children with periventricular leucomalacia and/or periventricular haemorrhage. Br J Ophthalmol 2003; 87:12:1345-1349.

14. Siatkowski R.M., Sanchez J.C., Andrade R., Alvarez A. The clinical, neuroradiographic, and endocrinologic profile of patients with bilateral optic nerve hypoplasia. Ophthalmology 1997; 104:3:493-496.

15. Mosin I.M. Anomalies of optic nerve excavation: clinical manifestations and differential diagnosis. Vestn ophthalmol 1999; 5:10-14.

16. Brodsky M.C., Glasier C.M. Optic nerve hypoplasia: clinical significance of associated central nervous system abnormalities on magnetic resonance imaging. Arch Ophthalmol 1993; 111:1:66-74.

17. Hoyt W.F., Rios-Montenegro E.N., Behrens M.M., Eckelhoff R.J. Homonymous hemioptic hypoplasia: fundoscopic features in standard and red-free illumination in three patients with congenital hemiplegia. Br J Ophthalmol 1972; 56: 537-545.

18. Volkov V.V. Glaucoma at pseudonormal pressure. M: Medicine 2001; 352.

19. Kurysheva N.I. Glaucoma optic neuropathy. M: MEDpress-inform 2006; 136.

20. Häussler M., Schäfer W.-D, Neugebauer H. Multihandi-capped blind and partially sighted children in South Germany I: prevalence, impairments and ophthalmological findings. Dev Med Child Neurol 1996; 38: 12: 1068-1075.

21. Herman D.C., Bartley G.B., Bullock J.D. Ophthalmic findings of hydranencephaly. J Pediat Ophthalmol Strabismus 1988; 25:2:106-111.

Relevance. Optic nerve hypoplasia (OHH) occurs in economically developed countries with a frequency of at least 7 cases per 100,000 population and is the cause of low vision and blindness in 5-6% of cases. Identification and adequate verification of optic nerve head abnormalities in children in the first months of life is important not only for their timely ophthalmological rehabilitation, but also plays an extremely important role for genetic counseling and early diagnosis of systemic diseases associated with optic nerve malformations in infants.

Due to the small number of publications devoted to ONH and its connection with systemic pathology, ophthalmologists are not sufficiently informed about the nature of the course and clinical features of some diseases from this group, which leads to a high frequency of diagnostic errors and unsatisfactory functional treatment results.

Target. To study diagnostic criteria for ONH in children.

Material and methods. The results of a neuro-ophthalmological examination and observation of 25 children with ONH aged from 7 to 16 years were analyzed. The collection of material was carried out at the Republican Clinical Ophthalmological Hospital. All patients underwent: collection of anamnestic data, clinical and ophthalmological examination.

Results. It has been established that the main causes of the development of ONH are pre- and perinatal lesions of the central nervous system (periventricular white matter) of the fetus, caused by hypoxic-ischemic disorders (32%), intrauterine infection (8%) and chronic toxic effects (4%). ONH can affect both one (44%) and two (56%) eyes with approximately equal frequency. ONH is characterized by typical ophthalmoscopic manifestations - a decrease in the size of the ONH (in 100%) of cases, its decoloration (48%), the “double ring” symptom (44%), corkscrew-shaped tortuosity of the retinal vessels (32%), absence of macular and foveolar reflexes (96% ). ONH was verified in all cases by fundus examination.

Children with ONH have a high level of ametropia (92%), oculomotor disorders (80%), concomitant changes in the anterior and posterior segments (64%), complicating its diagnosis and aggravating visual deprivation, which causes the frequent development of amblyopia.

As a result of neuroradiological studies, pathological changes in the brain were identified in 72% of patients. Some of these anomalies may not cause neuroendocrine disorders, in particular, agenesis of the septum pellucida (found in 32% of patients) and hypo- or agenesis of the corpus callosum (40%). In children with bilateral lesions, neuroradiological examination reveals CNS pathology almost 3 times more often (p
In all children with ONH, a decrease in the vertical and/or horizontal diameter of the ONH disc, decreased reflectivity and thinning were found (p
With ONH, light perception for blue and green colors and the degree of light perception are more severely affected, which indicates irreversible processes occurring in the optic nerve and persistent ischemia and reflects the coefficient of vision loss. The obtained CSFM data can serve as a differential diagnostic criterion.

Conclusions. 1. The main reasons for the formation of ONH are pre- and perinatal lesions of the periventricular white matter of the fetal brain, caused by hypoxic-ischemic disorders (32%), intrauterine infection (8%) and chronic toxic effects (4%). 2. Due to the prevalence of systemic pathology in children with ONH, during their observation it is necessary to use radiological diagnostic methods: in all cases - neurosonography, and in children at risk (with bilateral lesions, when ONH is combined with neonatal hypoglycemia and/or prolonged jaundice) — magnetic resonance and ultrasound examination of the abdominal organs and retroperitoneal space.

One of the most unfavorable processes occurring in the optical apparatus of the eye is the death of its nerve fibers. This pathology is called atrophy. The optic nerve serves as a bridge connecting the brain and eyes. Thanks to his work, a person can not only see, but also realize what he sees.

With the help of impulses, information comes from the organ of vision directly to the parietal lobe of the brain and its cortex. The received data is processed and a person can see and realize what is in front of him. This process is so acute and lightning fast that people do not notice it. However, any pathological changes in the optical apparatus immediately become noticeable and make themselves felt.

Complete atrophy of the optic nerve or destruction or death causes many serious consequences for the eyes. Dead fibers are unable to transmit impulses to the brain. Therefore, patients face partial or complete loss of vision, depending on how damaged the nerve is. Visual fields may become narrower and color perception may be impaired. All these changes will be reflected in the study of the optic nerve head. The ICD code encrypts the pathology as H47.

According to statistics, this disease accounts for only 1–1.5% of the total mass of ophthalmological diseases. However, 20 to 25% can lead to atrophy and blindness. At the cellular level, destruction of the nerve elements in the retina and their transformation occurs, which affects the capillary network of the optic nerve and its trunk. As a result, it becomes thinner and dies, losing its functional purpose.

Reasons

Atrophy is a consequence of many pathological processes. Depending on the factors that caused it, the disease can be divided into 2 types:

• Hereditary or congenital optic atrophy, which can occur in infants and older children. This condition is usually caused by a genetic defect or mutation in a chromosome. Leber optic atrophy and optic nerve hypoplasia are common;
• Acquired, which occurs in adults due to various diseases that appear over the course of life.

The second group of atrophies is common. Acquired pathology occurs in the following conditions:

• Glaucoma;
• Compression of the vessels that supply the nerve with tumors or an abscess;
• Myopia;
• Atherosclerosis;
• Thrombosis;
• Inflammatory processes in blood vessels - vasculitis;
• Arterial hypertension;
• Diabetes mellitus;
• Traumatic injury;
• Intoxication of the body due to acute respiratory viral infections, consumption of alcohol or drugs, nicotine.

Another common classification is the division of the atrophic process depending on the location of the lesion. Destruction can be:

• Ascending, in which the damage affects the eye and has not yet reached the optic nerve. The pathological process proceeds towards the brain, spreading from the upper layer of the eye inward. More common in glaucoma and myopia;
• Descending, developing as the process moves to the optic nerve head, which is located on the retina. This damage occurs with aplasia or hypoplasia of the optic nerve head, retrobulbar neuritis and trauma in the chiasm, as well as with pituitary tumors.

Symptoms

The manifestations of visual neuropathy depend on its type. Depending on where the destructive process is located, how damaged the fibers are and clinical signs will form. The main symptoms of destruction of the optical apparatus are:

• Decreased visual acuity – amblyopia. At the same time, the patient sees the world around him unclearly, it becomes difficult for him to see objects around him;
• Change in visual field – anopsia. Normally, this is the complete picture that a person sees without blinking, looking in front of him. If this function is impaired, “tunnel vision” may occur. At the same time, the world is seen as if through a telescope. Another disorder is the appearance of mosaic dark spots before the eyes. In this case, some part of the image may be missing;
• A change in color vision that makes it difficult to recognize different shades. First, the ability to distinguish between green and then red is lost;
• Slower recovery of optical functions when moving from an illuminated space to darkness, and vice versa.

Each of the emerging signs causes discomfort to the patient and immediately attracts attention. Don't ignore warning signs. The earlier medical care is provided, the higher the chance of maintaining health.

Diagnostics

To identify the disease, an ophthalmologist must conduct a comprehensive examination, which will help establish the criteria for atrophy. Patients are prescribed instrumental diagnostics, which makes it possible to differentiate the pathology of the visual apparatus from the brain. The most common research methods are:

• Ophthalmoscopy, which allows you to identify the condition of the optic nerve head at the moment;
• Perimetry helps in determining the edges of the visual field and identifying their defects - scotomas;
• Color testing, which is aimed at detecting pathologies in shade recognition;
• B-scanning ultrasound of the eye;
• Computed tomography (CT);
• Angiography of the vessels of the retina and brain, to determine the location of impaired blood circulation;
• Craniography or radiography of the skull bones. This is necessary to identify the condition of the bone canal of the optic nerve. This method aims to discover what may be causing the suspected compression;
• Magnetic resonance imaging (MRI) allows you to clearly see the fibers of the nervus opticus and assess their structural state;
• Laboratory blood tests to determine the presence or absence of inflammation or infection.

A consultation with a geneticist may be scheduled to determine whether the pathology is inherited or acquired during life.

Treatment

It is not possible to overcome optic nerve atrophy. Modern medicine gives a chance to stop the development of the pathological process. The main goal is to eliminate the underlying disease that caused the destruction. Depending on the initial process, treatment will be appropriate.

For viral etiology of atrophy, antibacterial therapy is needed. If a tumor or cyst is present, an examination by a neurosurgeon is required. To improve the condition of the visual apparatus, treatment is carried out through:

• Physiotherapy using electrophoresis, magnetic stimulation, ultrasound, oxygen therapy;
• Medicines from the group of angioprotectors and vasodilators;
• Reflexology.

Stopping the development of pathology at the beginning gives a chance not to go blind. The later appropriate treatment is started, the worse the consequences for the patient. If the patient's vision has reached a level below 0.01, then the therapy will not be effective.

Modern methods of treatment

Today, medicine is trying to find a way to cope with optic nerve atrophy. To achieve this, many research experiments are carried out. Stem cell treatment deserves great attention. Many medical industries are pinning their hopes on this method of therapy. Ophthalmology is no exception.

Stem cells are the original link of any body system. The progenitor of everything. All cells of the body are formed from them. Before specialization, they are stem cells and contain active substances - cytokines and interleukins, as well as growth factors. They are needed to create new cells. Mastering the technology for handling these structures represents great opportunities for medicine. In particular, to create new organs and tissues.

Unfortunately, scientists are not yet able to grow the optic nerve to replace the atrophied one. However, this practice still exists today. Using an injection, the patient is injected with stem cells into the area of ​​the optic nerve. This manipulation is carried out every 2 hours 10 times a day.

However, such a procedure is difficult due to the need for surgical intervention. Therefore, the method was slightly modified. Now stem cells are implanted into patients in 3 procedures with a time interval of 3 to 6 months. Simple lenses are used as the basis for the stem cell carrier. The procedure has received good reviews from patients, however, its cost is high.

Physiotherapy

One of the methods of treating optic atrophy, which is unfairly not given enough attention, is physical therapy. The impact is carried out using special devices and medications. You can be treated with physiotherapy through:

• Acupuncture;
• Electrophoresis;
• Magnetic, laser, radiation and electrical stimulation of the optic nerve.

These methods make it possible to normalize blood supply and metabolic exchange in the affected optical structure. With hypoplasia of the optic nerve, this is impossible due to the fact that the pathology arose due to underdevelopment at the embryonic level.

Surgical treatment

If the nerve is compressed, surgery may be indicated. Normally, the optic nerve passes freely through the bone canal. There should be no obstacles in his way. With pathological changes in the bone skull or neoplasms, a block occurs for the passage of fibers. In addition, the feeding vessels are also compressed. Optic nerve ischemia develops.

Surgical intervention helps eliminate compression of the fibers and increase the diameter of the vessels that feed it. Nerve ischemia can be reversible. Surgical operations performed for atrophy are as follows:

• Vasoreconstructive;
• Implantation of electrodes into the optic nerve head;
• Revascularization.

Forecast

The outcome of the disease will depend on several factors - the time of onset of the process, the location, the assistance provided, as well as the patient’s concomitant diseases. Whatever the optic nerve atrophy, it is an irreversible process. The ability to see cannot be completely restored. But it is possible to stop the pathological destruction. Loss of vision or its decline may cause the patient to be assigned a disability group by the ITU.

Video

The optic disc is a special structure that is visible in the fundus of the eye when examined with an ophthalmoscope. Visually, this area appears as a pink or orange oval-shaped area. It is located not in the center of the eyeball, but closer to the nasal part. The position is vertical, that is, the disk is slightly larger in height than in width. In the middle of this area in each of the eyes there are noticeable recesses called eye cups. Through the center of the cups, blood vessels enter the eyeball - the central ophthalmic artery and vein.

The nipple or disc is the site where the optic nerve is formed by the processes of retinal cells

The characteristic appearance of the optic disc and its sharp difference from the surrounding retina are due to the fact that there are no photosensitive cells (rods and cones) in this place. This feature makes this area “blind” in terms of the ability to perceive images. This blind area does not interfere with overall vision because the optic disc measures only 1.76 mm by 1.92 mm. Although the eye cannot “see” in this particular place, it provides other functions of the optic nerve head, namely the collection and transmission of nerve impulses from the retina to the optic nerve and further to the visual nuclei of the brain.

Characteristics of the optic nerve damage

Congestive optic disc (PCSD) is a condition characterized by impaired functionality due to the occurrence of non-inflammatory edema.

The causes of a stagnant disc lie in the disruption of venous and lymphatic outflow from the retina of the eye with increased intracranial pressure.

This indicator can increase for many reasons: intracranial tumor, traumatic brain injury, intracranial hematoma, infectious inflammation and swelling of the membranes or medulla, hydrocephalus, vascular arthritis, spinal cord diseases, tuberculomas, echinococcosis, orbital diseases.

The shorter the distance from the space-occupying lesion to the cerebral sinuses, the more pronounced the intracranial pressure and the faster the congestive optic disc develops.

Symptoms of disc edema: there is an increase in size, blurring of the boundaries, protrusion (prominence of the disc) into the vitreous body. The condition is accompanied by hyperemia - the central arteries are narrowed, and the veins, on the contrary, are dilated and more tortuous than normal. If the stagnation is severe, then hemorrhage in its tissue is possible.

Glaucoma causes damage to the optic nerve in the form of its excavation and stagnation

With glaucoma or intraocular hypertension, excavation of the optic nerve head occurs, that is, an increase in the deepening of the central “eye cup”. Also, the constant pressure of the intraocular fluid mechanically disrupts the microcirculation of blood in the nerve papilla, the result of which is the development of stagnation and partial atrophy. The fundus picture shows paleness of the nipple. With complete atrophy, it is gray, since the vessels are narrowed to the maximum.

Causes of this type of atrophy:

• syphilis;
• tumors in the brain;
• neuritis, encephalitis, multiple sclerosis;
• traumatic brain injury;
• intoxication (including methyl alcohol);
• some diseases (hypertension, atherosclerosis, diabetes mellitus);
• ophthalmological - thrombosis of the central artery in uveitis, infectious diseases of the retina.

If swelling of the nerve nipple persists for a long time, then processes leading to secondary atrophy also develop in it, which leads to loss of vision.

Visually, atrophy is characterized by decoloration (loss of normal color intensity). The process of discoloration depends on the localization of the atrophy, for example, with damage to the papillo-macular fascicle, the temporal region turns pale, and with diffuse damage, the entire area of ​​the disc turns pale.

Optic disc with increased intracranial pressure at various stages of the disease. There is a gradual increase in diameter, blurring of boundaries, disappearance of color and expression of the vascular network

The lesion may be unilateral or develop in both eyes. Also, damage to one optic nerve by a tumor at the base of the brain (primary atrophy) may be accompanied by the development of secondary atrophy in another disc due to a general increase in intracranial pressure (in Foster-Kennedy syndrome).

Disorders associated with the optic nerve nipple affect the quality of vision. The sharpness decreases, and areas of partial loss of fields appear. As the condition worsens and the size of the disc increases, the blind spot also increases proportionally. In some patients, these phenomena may not occur for quite a long time. Sometimes, with chronic vision loss, sudden loss of vision is possible due to a sharp spasm of blood vessels.

Similar diseases

The rate of decrease in visual acuity (visus) is used to differentiate the diagnosis of optic nerve disease from neuritis. With inflammation of the optic nerve, vision immediately drops sharply at the onset of the disease, and the development of edema is expressed in its gradual decrease.

A pseudocongestive optic disc also requires differential diagnosis. This pathology is genetic and bilateral in nature. The nerve discs are enlarged, have a gray-pink color and protrude significantly above the surface of the retina. The boundaries are blurred, have a scalloped appearance, blood vessels diverge radially from them, and the tortuosity of the veins is increased. The formation of a picture of pseudo-stagnation is due to the congenital proliferation of embryonic glial tissue and the formation of drusen from it, including calcium particles. These inclusions are located closer to the inner (nose side) edge of the disc. With pseudostagnation, the appearance of small hemorrhages is also noted, since the vessels are injured by drusen. In the absence of drusen, visual acuity may be normal, but their presence almost always leads to a decrease in visual acuity and the appearance of central scotomas.

Optical coherence tomography or retinal tomography helps to reliably diagnose pathologies. These studies are capable of assessing the structure of the nerve papilla layer by layer and determining pathological changes in it, their degree, visualizing choriocapillaris, hidden edema, scarring, inflammatory foci and infiltrates - formations that cannot be seen with the naked eye.

The result of scanning the optic nerve head with optical coherence tomography

OCT allows you to determine the final diagnosis and monitor the response to therapy.

Congenital anomalies

Congenital diseases inherited in an autosomal dominant manner also include coloboma of the optic disc, in which many small depressions filled with retinal cells are formed throughout its area. The cause of such formations is improper cell fusion at the end of embryonic development. The optic disc becomes larger than normal, and a spherical notch with clear silver-white boundaries is formed along its edge. The lesion can be unilateral or bilateral. Clinically manifested by a high degree of myopia (myopia) and myopic astigmatism, as well as strabismus.

Coloboma of the optic nerve head

The presence of congenital coloboma increases the likelihood of macular rupture, its dissection with further retinal detachment.

Since the pathology is genetically determined, it occurs in combination with other disorders that appear in children from birth:

• epidermal nevus syndrome;
• focal Goltz skin hypoplasia;
• Down syndrome.

Another disease that is congenital is optic disc hypoplasia. It is characterized by underdevelopment of the long processes of retinal nerve cells against the background of normal formation of supporting cells. Insufficiently developed axons have difficulty forming the optic nerve papilla (it is pale pink or gray, surrounded by a radial area of ​​depigmentation).

The pathology of the nervous tissue is reflected in the appearance and functionality of the visual organs; the following are ignored:

• visual field defects;
• violation of color perception;
• afferent pupillary defect;
• macular hypoplasia;
• microphthalmos (reduction in the size of the eyeball);
• strabismus;
• nystagmus.

In the photo, aniridia (an eye without an iris) is a congenital pathology that is often combined with hypoplasia of the optic nerve nipple

The causes of congenital hypoplasia are impaired development of nervous tissue in the prenatal period under the influence of the following factors:

• genetic disorder of cell division,
• small amount of amniotic fluid;
• ionizing radiation;
• intoxication of the maternal body with chemicals, drugs, nicotine, alcohol, drugs;
• systemic diseases in the mother, for example, diabetes;
• infections and bacterial diseases.

Unfortunately, hypoplasia (small number of nerve fibers) is almost impossible to cure. For unilateral lesions, treatment is aimed at training the functions of the weaker nerve by applying occlusive dressings to the stronger eye.

Treatment

Treatment for a congestive disc depends on the cause.

First of all, it is necessary to eliminate space-occupying formations in the skull - tumors, edema, hematomas.

Typically, corticosteroids (prednisolone) and the introduction of hyperosmotic agents (glucose solution, calcium chloride, magnesium sulfate), diuretics (diacarb, hypothiazide, triampur, furosemide) are used to eliminate edema. They reduce extravasal pressure and restore normal perfusion. To improve microcirculation, Cavinton and nicotinic acid are administered intravenously, Mexidol (intravenously and into the retrobulbar space - an injection in the eye), and a nootropic drug - Fezam - is prescribed orally. If stagnation occurs against the background of hypertension, then treatment is aimed at treating the underlying disease (hypertensive therapy).

Sometimes intracranial pressure can only be reduced by cerebrospinal puncture.

The consequences of stagnation require improvement of tissue trophism - vitamins and energy supplements:

• nicotinic acid;
• B vitamins (B 2, B 6, B 12);
• aloe extract or vitreous in injection form;
• riboxin;

A congested optic disc may not manifest itself for a long time, but can have catastrophic consequences, therefore, for the purpose of prevention, you should undergo an annual examination by an ophthalmologist for timely detection of the disease.