共同性斜视眼外肌病理分析

目的探讨共同性斜视眼外肌的病理变化与斜视发生的关系。方法对132例共同性斜视和22例麻痹性斜视病人行斜视矫正手术,将截除的外直肌或内直肌用95%酒精固定后送病理,在显微镜下观察眼外肌的组织结构。结果81例共同性外斜视中,内直肌退行性改变57例(70.4%),内直肌纤维化10例(12.3%),内直肌玻璃样变10例(12.3%),正常4例(4.9%);51例共同性内斜视中,外直肌退行性变18例(35.3%),外直肌纤维化28例(54.9%),外直肌玻璃样变5例(9.8%),22例麻痹性斜视中,13例内直肌和3例外直肌发生纤维化,6例外直肌发生玻璃样变。共同性斜视与麻痹性斜视直肌的病理结果经X~2检验P<0.01。恒定性外斜视与间歇性外斜视之间及先天性内斜视与共同性内斜视之间经X~2检验P<0.05。结论斜视的发生与眼外肌的结构异常有关,发病较久的恒定性外斜视比发病晚的间歇性外斜视其眼外肌发生纤维化的百分比较大,说明内直肌纤维化可能是外斜视形成的原因之一,斜视的病变程度与眼外肌功能是成反比的。     

The accuracy of ophthalmological measurements

Main principals of metrology of measurement being conducted in research studies and in practice of ophthalmologists are stated. Characteristics of casual and systematic errors are described and their causes explained. Concrete measures for increasing the accuracy of ophthalmologic measurements are proposed: coordination of works in research institutes and chairs of ophthalmological profile and metrologic organizations of the state standard on metrologic provision; publication of papers devoted to the methods of treatment of measurement results; introduction of foundations of metrology into the program of education for refreshment courses of physicians-ophthalmologists.     

Formation of congenital defects during ocular development. I. Embryogenesis of the eye and developmental birth defects

Formation of developmental congenital defects of organ of vision finds its direct basis in the course of eye embryogenesis. Author of this work presents on the base of the literature, the crucial stages of embryonal development of eyeball and its individual structures. At every stage of development, the critical moments are shown, when the disturbance of the developmental process may lead to the origination of different groups of congenital eye defects. The knowledge of the potential period of particular congenital eye defects formation, facilitates the identification of eventual teratogenic factors, that have acted during pregnancy. It enables, to state the activity of gradually discovered genes, that regulate the course of embryonal development of the eye.     

Reconstruction of the anterior chamber in posttraumatic epithelial ingrowths and epithelial anterior chamber cysts

The pathology of penetrating injuries of the cornea and corneal-scleral area with the ingrowth of epithelium and formation of anterior chamber cysts is characterized by polymorphism and can be defined by two main kinds: 1) plane ingrowth of epithelium along the posterior surface of the cornea involving the iris and the lens, and partially or totally obliterating the anterior chamber; 2) formation of cysts with a locked cavity and clear content. In 42 patients with epithelial ingrowths as a result of penetrating injuries of the cornea and corneal-scleral area, the following kinds of interventions were used: 1) transplantation of posterior layers of the cornea with dissection of epithelial growth; 2) dissection of anterior chamber cysts; 3) cystectomy; 4) dissection of the cite of epithelial ingrowth by means of corneal transplantation with removal of the cyst or reconstruction of the anterior chamber. Immediate and remote results of surgical treatment, complications in various forms of the mentioned pathology are described.     

The effect of styrene and tetrachloroethylene on electrical activity of the retina

Clinical investigations of ERG of 202 workers having a contact, during a process of production, with styrole and tetrachlorethylene vapours and of 50 workers having no such a contact as well as experimental investigations of ERG of isolated retina of a guinea-pig (n = 50) subjected to the action of these substances have shown that the action of styrole and tetrachlorethylene leads to a fall of electric activity of the retina. Functional changes develop both in photoreceptors and neuronal elements of the retina. These changes are directly proportional to the degree of styrole and tetrachlorethylene actions and can serve as an early sign of intoxication of the body.     

Direct, vec and other squares, and sample variance—covariance of dioptric power

Matrices can be multiplied in several ways. As a result one can define a number of distinct squares of the dioptric power matrix. Additional squares can be defined for matrices vectorized by means of the vec and vech operators. These various squares can form the basis for the definition of variance and covariance of samples of dioptric powers. The complete form of the variance of dioptric powers is a 4 x 4-matrix (a variance-covariance matrix) with 10 distinct elements; four of them represent the variances of the four elements of the dioptric power matrix and the other six are the covariances between those four elements. For thin systems there are only six distinct elements of the variance-covariance matrix, three of which are variances and three covariances. Examples are included that show the calculation of the different types of squares and the variance-covariance matrix for a sample of equivalent powers of thick bitoric lenses and for a sample of powers of thin systems, including conventional refractive errors. Variances calculated in the past, including those of nearest equivalent spheres and Gartner's and Churm's variances turn out to be components (or combinations of components) of the generalized variance defined here. They are valid as far as they go but they do not completely represent the dispersion of a sample of dioptric powers. The complete variance-covariance matrix does represent the dispersion fully and thus opens the way for the formal statistical analysis of measurements of dioptric power.     

弱视复发因素探讨

了解弱视治愈远期疗效的影响因素。方法　对259例(448眼)基本治愈的弱视患者进行了3年以上的随访观察。经散瞳验光后证实视力下降至≤0.9时为弱视复发眼。结果　本组弱视复发率为29.24%。屈光参差性弱视和斜视性弱视的复发率明显高于屈光不正性弱视的复发率;弱视程度越重,复发率就越高;中心注视性弱视复发率低于旁中心注视性弱视复发率。结论　弱视复发率因弱视类型和弱视程度不同而异。随停止治疗的时间逐渐延长,弱视复发病例逐渐减少。对于易复发的弱视类型应进行重点监测。     

The surgical characteristics of patients with postburn vascularized leukomas

In order to avoid neovascularization of corneal grafts in keratoplasty, 3 variants of keratoplasty are proposed for surgical treatment of after-burn vascularized leukomas of category III and IV. The variants were used for treatment of 25 patients with sequelae after chemical and thermic eye burns of degree II and III. The variants of keratoplasty were differentially used depending on the severity and the character of cicatricial after-burn changes in the eye. The schemes of the variants are proposed. The analysis of immediate and remote results (from 5 months to 4 years) after the usage of the three variants of keratoplasty has shown effectiveness of the proposed reconstructive interventions, the expediency of a differential approach to the choice of the method of keratoplasty, the importance of using collagenic coverings for protection of the graft from a mechanic trauma, infection as well as for stimulating the growth corneal epithelium.     

Role of the sclera in the development and pathological complications of myopia

Myopia is one of the most prevalent ocular conditions and is the result of a mismatch between the power of the eye and axial length of the eye. As a result images of distant objects are brought to a focus in front of the retina resulting in blurred vision. In the vast majority of cases the structural cause of myopia is an excessive axial length of the eye, or more specifically the vitreous chamber depth. In about 2% of the general population, the degree of myopia is above 6 dioptres (D) and is termed high myopia. The prevalence of sight-threatening ocular pathology is markedly increased in eyes with high degrees of myopia ( > -6 D). This results from the excessive axial elongation of the eye which, by necessity, must involve the outer coat of the eye, the sclera. Consequently, high myopia is reported as a leading cause of registered blindness and partial sight. Current theories of refractive development acknowledge the pivotal role of the sclera in the control of eye size and the development of myopia. This review considers the major biochemical mechanisms that underlie the normal development of the mammalian sclera and how the scleral structure influences the rate of eye growth during development. The review will characterise the aberrant mechanisms of scleral remodelling which underlie the development of myopia. In describing these mechanisms we highlight how certain critical events in both the early and later stages of myopia development lead to scleral thinning, the loss of scleral tissue, the weakening of the scleral mechanical properties and, ultimately, to the development of posterior staphyloma. This review aims to build on existing models to illustrate that the prevention of aberrant scleral remodelling must be the goal of any long-term therapy for the amelioration of the permanent vision loss associated with high myopia.     

A model of the dynamics of retinal activity during natural visual fixation

During visual fixation, small eye movements keep the retinal image continuously in motion. It is known that neurons in the visual system are sensitive to the spatiotemporal modulations of luminance resulting from this motion. In this study, we examined the influence of fixational eye movements on the statistics of neural activity in the macaque's retina during the brief intersaccadic periods of natural visual fixation. The responses of parvocellular (P) and magnocellular (M) ganglion cells in different regions of the visual field were modeled while their receptive fields scanned natural images following recorded traces of eye movements. Immediately after the onset of fixation, wide ensembles of coactive ganglion cells extended over several degrees of visual angle, both in the central and peripheral regions of the visual field. Following this initial pattern of activity, the covariance between the responses of pairs of P and M cells and the correlation between the responses of pairs of M cells dropped drastically during the course of fixation. Cell responses were completely uncorrelated by the end of a typical 300-ms fixation. This dynamic spatial decorrelation of retinal activity is a robust phenomenon independent of the specifics of the model. We show that it originates from the interaction of three factors: the statistics of natural scenes, the small amplitudes of fixational eye movements, and the temporal sensitivities of ganglion cells. These results support the hypothesis that fixational eye movements, by shaping the statistics of retinal activity, are an integral component of early visual representations.     

Awareness of age-related macular degeneration in adults: the results of a large-scale international survey.

BACKGROUND: Early detection and prompt implementation of appropriate rehabilitation services and therapy can help minimize the long-term disability that results from age-related macular degeneration (ARMD). The level of awareness of ARMD among the general public may influence early detection of this disease. METHODS: Random samples of European and North American populations were interviewed in an international survey designed to assess the attitudes of people to eye examinations, awareness of the causes of vision loss, awareness of ARMD, and knowledge of its treatment options. RESULTS: A total of 7,830 adults of at least 18 years of age were questioned. The main finding was that knowledge of ARMD is poor-the majority of respondents (70%) were not at all familiar with ARMD. Only 2% of participants knew that ARMD is the leading cause of severe vision loss in adults 50 years of age or older, while a majority of those surveyed (75%) was unaware of treatments available for ARMD. CONCLUSIONS: These data show that there is low public awareness of ARMD, which may result in people with ARMD not receiving prompt medical advice and treatment. There is a need for a wide-ranging educational initiative to increase awareness of ARMD and highlight the importance of undergoing regular eye examinations.     

Insertion anomalies of the horizontal muscles and dysfunctions of the oblique muscles in the A-V patterns

Insertion anomalies of the horizontal rectus muscles and dysfunctions of the oblique muscles were studied in 141 cases with A-V patterns of 824 patients with horizontal strabisums. The frequency of insertion anomaly among all cases of A-V pattern studied was 49.6%, there were more V pattern insertion anomalies than in those of A pattern, but the ratio of insertion anomalies in each type of A-V pattern was more in the A pattern than in the V pattern. In the oblique muscles, overaction of the inferior oblique muscle in the V pattern and of the superior oblique muscle in the A pattern were frequently encountered and insufficient action of the oblique muscles occurred more frequently in cases A-V esotropia than in cases of exotropia. In cases of combination of insertion anomaly of the horizontal rectus muscles with dysfunction of the oblique muscles, insertion anomaly was involved in 91.3% of cases of overaction of the superior oblique muscles, but only in 37.4% of cases of overaction of the inferior oblique muscles. The combination of insertion anomalies with dysfunction of the oblique muscles suggests a possible existence of simulated dysfunction of the oblique muscles in some cases of dysfunction of the oblique muscles diagnosed preoperatively. At the choice of a procedure in surgical correction, a confirmation of insertions of the horizontal muscles during operations is needed, and for this purpose the perilimbal incision is more appropriate than the fornix incision.     

Results of intraocular lens implantation in cataract complicated by medium and high myopia]

Results of surgical treatment of cataract complicated by medium and high myopia are analyzed. The main group consisted of 90 patients (96 eyes) subjected to extracapsular cataract extraction with implantation of posterior-chamber intraocular lenses and the reference group of 128 patients in whom cataract was extracted without implantation of artificial lens. The study included creation of a mathematical model of myopic eye with estimation of pressure fluctuations in various zones of the eye, developing during transposition of the vitreous during patient's movements (head movements, jumps, falling) and the damping effect of the lens in the ocular system. It was proven by mathematical calculations that transpositions of jelly fractions of the vitreous decreased by 70% in an eye with the lens in comparison with their transposition in aphakia. Clinical studies demonstrated the efficiency of intraocular correction of aphakia in high myopia: implantation of an intraocular lens decreases the risk of detachment of the retina during the postoperative period and helps attain the desired refraction.     

Outcome study of stereopsis in relation to duration of misalignment in congenital esotropia.

PURPOSE: A recent outcome study of Randot stereopsis in congenital esotropia reported early surgical alignment is associated with a higher percentage of patients with stereopsis and a higher quality of stereopsis because early surgery minimized the duration of misalignment. We compared the Titmus stereopsis with the duration of misalignment and the age of alignment for a group of patients who were surgically aligned by 24 months of age. METHODS: The data previously obtained in a study of 90 patients aligned by 2 years of age, examined in a masked, independent evaluation for binocularity was analyzed. The age of alignment and duration of misalignment was correlated with the percentage of patients with stereopsis and quality of the stereopsis result as determined by the Titmus vectograph overlay. RESULTS: Patients aligned by 6 or 12 months of age or within 6 or 12 months of duration of misalignment did not differ in percentage with stereopsis. However, patients aligned after 12 months of age did show a decrease percentage with stereopsis (P <.05, power 0.8). The quality of the stereopsis that was established was similar for those aligned by 6 or 12 months (P >.05, power 0.8). The quality of stereopsis, however, was decreased for patients with duration of misalignment greater than 12 months (P <.001, power 0.8). CONCLUSION: Alignment within 1 year of age or within 12 months of misalignment favorably affects the percentage of patients who develop stereopsis in the treatment of congenital esotropia. The quality of the stereopsis result is affected by the duration of the misalignment, rather, than the age of alignment per se.     

The characteristics of the engorgement of the eye vessels in the dynamics of the burn process]

Peculiarities of eye blood filling in dynamics of a burn process of different severity have been studied in 29 patients with mild burns, in 19--with moderate, in 56--with severe, and in 32--with extremely severe. It is found that changes in ocular vessels blood filling correlate with severity of the burn, the degree of the development of the burn process. The usage of rheopolyglucine and cavinton in a complex treatment of eye burns positively influences the course of the burn disease. The degree of the increase of eye blood filling is in inverse dependence on the degree of destructive changes in eye tissues. Restoration of blood filling as a result of the usage of rheopolyglucin and cavinton in the shortest terms after burn stimulates the stoppage of inflammatory-destructive changes and acceleration of regenerative processes.     

Clinical and morphological bases of inferior exterior tarsopexy

Involution processes caused by elongation of the lower eyelid are associated with loss of elastic fibers, destruction of collagen fibers, and fibrous degeneration of the distal fragment of the tarsal plate. The authors present a morphological validation of resection of the lower pedicle of the external ligament of the eyelid and shortening of the lateral part of the tarsal plate. Modified suture fixation to the orbital external wall periosteum and external retinaculum is proposed, ensuring adequate tension of the lower eyelid. High functional efficiency of the operation is analyzed on 66 clinical cases; the incidence of complications was low and good cosmetic results were attained (period of observation 3-52 months).     

Histopathologic analysis of experimental autoimmune uveitis attenuated by intracameral injection of S-antigen

Pretreatment of rats and mice with intracameral injections of soluble protein antigens induces Anterior Chamber Associated Immune Deviation, an unusual spectrum of immune reactivities that is dominated by suppression of the efferent limb of the immune response. Pretreatment of Lewis rats with an intracameral injection of S antigen (S Ag) mitigates against the development of clinically detectable experimental autoimmune uveitis if these rats are subsequently injected with a uveitogenic dose of S Ag. In this report, we describe a series of histopathologic studies designed to determine the extent and severity of changes that occur in the eyes of rats pretreated with intracameral S Ag. The results indicate that pretreatment with intracameral injection of S Ag alone or mixed with Complete Freund's Adjuvant significantly inhibited the development of severe uveoretinitis. In the eyes of the majority of rats, the histologic appearance was completely normal, without any evidence of pathologic changes. A minority of rats displayed clinical evidence of uveitis, and their eyes contained histopathologic changes. These changes suggested that a mild form of uveoretinitis had taken place. It is proposed that S Ag-specific suppression of delayed hypersensitivity is induced by the anterior chamber injection of this antigen, and that this suppressor activity accounts for the reduced severity of disease in the eyes of treated rats. The potential physiologic significance of suppression in response to exposure to unique ocular antigens is discussed.     

下直肌后退术治疗甲状腺相关眼病性眼外肌病变

目的 探讨下直肌后退术治疗甲状腺相关眼病性眼外肌病变的适应证、手术特点和效果等.方法 回顾分析诊治的39例甲状腺相关眼病性眼外肌病变需作下直肌后退术的患者.其中男24例:女15例:年龄28.0～66.0岁(平均49.9岁).手术方式包括下直肌后退术31例;下直肌断腱术1例:下直肌后退+上白:肌缩短3例;下直肌后退+内直肌后退2例:右眼下直肌后退+左眼内直肌后退外直肌缩短1例;左眼下直肌后退+右眼上直肌后退下直肌缩短1例.术后平均随访1.4年.结果 术后25例正位,复视消失;欠矫5～15°10例,复视明显改善:过矫4例.20°以内的下斜视行下直肌后退术每1mm后退平均可矫止2.5°.大度数垂直斜(20°～＞45.),78.9%(15/19)行患眼下直肌后退术可矫正;21.0%(4/19)需行下直肌断腱术或加患眼上直肌缩短术.所有大度数垂直斜均需作眼球缝线固定术.结论 下直肌后退术治疗甲状腺相关眼病性眼外肌病变的限制性下斜视效果满意,文中对手术时机、手术特点、手术方式与手术注意点进行了详细的讨论.     

The results of simulating congenital pathology of the extraocular muscles

The paper describes results after calculating the distribution of tensions in the cornea in case of anomalies in the action and insertion of oculomotor muscles. The calculation was made on the basis of theories of thin coats considering the gradient of corneal thickness. By the results of the calculation, the lines of equal tensions (isochroms) were built, the forms of which is well correlated with clinical results. The calculation has shown that the rounding of one of the angles of interference rhombus and its displacement towards the centre of the picture speak about either a functional deficiency of a muscle inserted into the eye ball in this place or about displacement of the point of its insertion from the limbus along the meridian of its action; displacement of one the angles of interference rhombus from the meridian speaks about displacement of the point of efforts exertion of the corresponding muscle into the same direction. The calculation made confirms correctness of our knowledge about the nature and properties of interference pictures observed on the cornea in a polarised light.     

Irrigation therapy as a method of intensive care of ophthalmopathology in the posterior eye segment in children

Presented in the paper are data of a comparative analysis of efficiency of different methods of administration of drugs in neuritis and partial atrophy of the optic nerve. New techniques of application and fixation of irrigation systems in the retrobulbar and Tenon's space are described. Experimental and clinical data proving advantages of the new method of administration of drugs by an automatic pulse doser in the treatment of inflammatory diseases of the optic nerve are represented. The use of such intensive intermittent technique of administration of drugs in Tenon's space performed at the preliminary stage before electrostimulation of the optic nerve made the procedure by far more effective and ensured better treatment results.