Ampli-pulse phoresis in patients with partial optic nerve atrophy

A new complex method for treating partial atrophies of the optic nerve unites surgical, physiotherapeutic, and drug effects. One electrode is attached directly to the anterior segment of the optic nerve by a collagen infusion system and the other is fixed at the back of the neck. The involved optic nerve is exposed to sinusoidal modulated currents in the rectified mode, permitting direct drug electrophoresis in parallel with electric stimulation of nerve fibers. The efficiency of the method is two times higher than of standard treatment.     

Possibilities of spatial discriminative perimetry in the diagnosis of partial atrophy of the optic nerve

A method for investigating spatial discriminative sensitivity at a site of 20 degrees from the point of fixation is proposed for studies of changes in the ocular system at early stages of partial optic nerve atrophy. Normal values of distribution were determined on 20 volunteers. The main group consisted of 8 patients with initial glaucoma. Manifest changes in spatial discriminative sensitivity, correlating with changes in the central visual field, were detected in all patients with glaucoma. This method represents a variant of analysis of the resolving capacity of optic analyzer, allowing detection of its early changes.     

Dominant infantile optic nerve atrophy

The authors present an account of a family with an autosomal dominant infantile atrophy of the optic nerve. In three generations two men and three women were affected. With the clinical picture of simple atrophy of the optic nerve with a different degree of expressivity corresponded functional and fluoroangiographic changes. Disorders of colour vision were within the range of deuteroanomaly, deuteroanopia. The proband suffered also from tritanopia. The disease did not call for amaurotic training.     

Electrophysiological assessment of optic nerve disease

The electrophysiological findings in optic nerve and primary ganglion cell dysfunction are reviewed. The value of the pattern reversal visual-evoked potential (VEP) in the diagnosis of optic nerve disease, and the pattern appearance VEP in the demonstration of the intracranial misrouting associated with albinism, are discussed. The pattern electroretinogram (PERG) is used in the direct assessment of ganglion cell function. The use of PERG or multifocal electroretinography (mfERG), to enable the distinction between VEP delay due to optic nerve disease and that due to macular dysfunction, is described.     

Anterior optic nerve blood flow in experimental optic atrophy

This study attempts to establish whether neurogenic optic atrophy induces changes in anterior optic nerve circulation and to determine how noninvasive techniques of measuring blood flow in vivo compare to microsphere distribution. Five cats underwent unilateral optic nerve transection in the orbital apex and a sham procedure in the contralateral eye. Two to three months later, no abnormalities were detected by fluorescein angiography. Laser Doppler measurements demonstrated a 53% decrease in red blood cell speed through the capillaries of the atrophic optic nerve heads in vivo. Optic disk reflectance measurements of anterior optic nerve blood volume in vivo demonstrated a 51% decrease in the estimated blood volume of the capillaries in atrophic optic nerve heads. Flow was calculated on the basis of these noninvasive measurements and demonstrated an average decrease of 74% in optic atrophy. Histologic studies of microsphere distribution demonstrated an average decrease of 80% in flow to the anterior optic nerve in optic atrophy. These results suggest that anterior optic nerve blood flow is significantly reduced in primary neurogenic optic atrophy. This study also demonstrates that the noninvasive measurements of blood flow are substantiated by histologic evaluation of microsphere distribution.     

Bilateral optic nerve atrophy in myotonic dystrophy

PURPOSE: To document a case of bilateral optic atrophy in a patient with myotonic dystrophy. Myotonic dystrophy is an autosomal dominant disorder, genetically resulting from an expansion of an unstable CTG repeat in the 3'-untranslated region of a protein kinase gene (DMPK) on chromosome 19q13.3. METHODS: Case report, clinical examination, fundus photographs, visual fields, visual evoked potentials, electroretinograms, and genetic studies of a 56-year-old woman clinically diagnosed with myotonic dystrophy. RESULTS: The patient experienced decreased vision consisting of light perception with the right eye and 20/25 with the left. Fundus examination showed bilateral pallor of the optic disks. Intraocular pressure was normal. Visual field testing, visual evoked potentials, and electroretinogram were abnormal. A pathologic CTG expansion in the myotonic dystrophy gene was found. CONCLUSIONS: In a patient with myotonic dystrophy, confirmed with genetic molecular diagnosis, bilateral optic atrophy was present. Optic atrophy should be considered a possible complication of myotonic dystrophy.     

Dominant optic atrophy: Culprit mitochondria in the optic nerve

Dominant optic atrophy (DOA) is an inherited mitochondrial disease leading to specific degeneration of retinal ganglion cells (RGCs), thus compromising transmission of visual information from the retina to the brain. Usually, DOA starts during childhood and evolves to poor vision or legal blindness, affecting the central vision, whilst sparing the peripheral visual field. In 20% of cases, DOA presents as syndromic disorder, with secondary symptoms affecting neuronal and muscular functions. Twenty years ago, we demonstrated that heterozygous mutations in OPA1 are the most frequent molecular cause of DOA. Since then, variants in additional genes, whose functions in many instances converge with those of OPA1, have been identified by next generation sequencing. OPA1 encodes a dynamin-related GTPase imported into mitochondria and located to the inner membrane and intermembrane space. The many OPA1 isoforms, resulting from alternative splicing of three exons, form complex homopolymers that structure mitochondrial cristae, and contribute to fusion of the outer membrane, thus shaping the whole mitochondrial network. Moreover, OPA1 is required for oxidative phosphorylation, maintenance of mitochondrial genome, calcium homeostasis and regulation of apoptosis, thus making OPA1 the Swiss army-knife of mitochondria. Understanding DOA pathophysiology requires the understanding of RGC peculiarities with respect to OPA1 functions. Besides the tremendous energy requirements of RGCs to relay visual information from the eye to the brain, these neurons present unique features related to their differential environments in the retina, and to the anatomical transition occurring at the lamina cribrosa, which parallel major adaptations of mitochondrial physiology and shape, in the pre- and post-laminar segments of the optic nerve. Three DOA mouse models, with different Opa1 mutations, have been generated to study intrinsic mechanisms responsible for RGC degeneration, and these have further revealed secondary symptoms related to mitochondrial dysfunctions, mirroring the more severe syndromic phenotypes seen in a subgroup of patients. Metabolomics analyses of cells, mouse organs and patient plasma mutated for OPA1 revealed new unexpected pathophysiological mechanisms related to mitochondrial dysfunction, and biomarkers correlated quantitatively to the severity of the disease. Here, we review and synthesize these data, and propose different approaches for embracing possible therapies to fulfil the unmet clinical needs of this disease, and provide hope to affected DOA patients.     

Effectiveness of infrared exposure to periorbital areas in partial optic nerve atrophy of varying degrees

The paper gives the comparative results of infrared exposure, drug and multimodality treatment in partial optic nerve atrophy of varying degrees, as evidenced by Doppler, electrophysiological, and morphometric studies.     

Anterior optic nerve blood flow decreases in clinical neurogenic optic atrophy

Anterior optic nerve blood flow was studied in nine patients with unilateral neurogenic optic atrophy using noninvasive techniques. Disk reflectometry measurements from temporal sites demonstrated a significant reduction in the index of blood volume in atrophic optic nerves as compared with the contralateral optic nerves (P less than 0.00001). Laser Doppler measurements from the same temporal sites detected a significant reduction in the speed of blood (P less than 0.002). On average, blood volume was decreased by 49% +/- 11% and blood speed by 30% +/- 17%. Combining the results of these two techniques yielded a relative index of blood flow that showed a significant reduction in the atrophic nerves (P less than 0.0001), averaging 64% +/- 14% temporally. Nasally there was less reduction in blood flow. The results correlated well with clinical assessment of the degree of optic nerve damage (rho = 0.92, P less than 0.002). This study demonstrates that clinical neurogenic optic atrophy induces significant reductions in overall anterior optic nerve blood flow that are detected by these noninvasive techniques.     

Optic disc morphometry in simple optic nerve atrophy

This study was undertaken to evaluate the optic disc changes in eyes with non-glaucomatous optic nerve damage. The intra- and parapapillary region was evaluated morphometrically in 106 eyes of 56 patients with simple optic nerve atrophy (SONA) and in 107 normal eyes of 57 subjects. Colour stereo optic disc diapositives were used. Only one randomly chosen eye per subject and patient was taken for statistical analysis. Characteristics of SONA were: decreased visibility of the parapapillary retinal nerve fibers, diminished retinal vessel diameter, and area with pallor larger than area with cupping. Size and form of the optic disc, neuroretinal rim, peripapillary scleral ring, and zone Alpha and Beta of the parapillary chorioretinal atrophy were not significantly different. Also, distinctness of a tesselated fundus, frequency of optic disc haemorrhages and frequency of bared circumlinear or bared cilioretinal vessels did not differ significantly. These morphologic features are helpful in the diagnosis and differential diagnosis of SONA.     

原发性视神经萎缩患者视网膜电图明视负向反应振幅异常

目的研究视网膜电图(ERG)明视负向反应(PhNR)在原发性视神经萎缩进展中的变化特点以及与视网膜神经纤维层厚度(RNFLT)的关系。设计前瞻性、对照性研究。研究对象正常健康者18例(18眼)和原发性视神经萎缩稳定期患者15例(18眼)及7例(7眼)视神经挫伤导致视神经萎缩的患者。方法对正常健康者和原发性视神经萎缩者进行ERG和相干光断层扫描(OCT)检查,比较两组PhNR振幅,并将原发性视神经萎缩者的PhNR振幅与RNFLT进行相关分析;另对视神经挫伤导致视神经萎缩者随访半年,研究其PhNR振幅与RNFLT变化规律。主要指标PhNR振幅与RNFLT。结果稳定期原发性视神经萎缩组和对照组的ERG中暗视反应、最大反应、30Hz震荡电位的振幅及明视反应a波和b波振幅差异均无显著性意义,但原发性视神经萎缩组的PhNR振幅比对照组明显下降(P<0.01),而且PhNR的振幅与RNFLT显著相关(r=0.688,P<0.01)。视神经挫伤导致视神经萎缩的患者随访第1~3个月,PhNR振幅下降先于RNFLT的变薄。结论原发性视神经萎缩眼ERGPhNR振幅明显下降甚至消失,且PhNR振幅下降早于RNFLT变薄。     

Electrophysiological tests in early and differential diagnosis of some hereditary retinal and optic nerve diseases

PURPOSE: The goal of our study was to determine the value of electrophysiological tests in early and differential diagnosis of some hereditary retinal and optic nerve diseases. MATERIAL AND METHODS: Review article on the basis of own experiences and results of another authors concerning to EOG, ERG, PERG, MfERG and VEP tests in evaluation of hereditary, stationary and progressive retinal diseases, as well as optic nerve diseases. RESULTS: Electrophysiological tests can be abnormal even in patients without fundus changes seen in routine ophthalmological examination. CONCLUSIONS: Electrophysiological tests are useful in early and differential diagnosis of some hereditary retinal and optic nerve diseases. General ophthalmologists should remember about its application, especially in difficult diagnostic cases.