RESUMO
Purpose. The study investigates corneal and higher-order internal aberrations in patients with amblyopia of different etiologies and their relationship with visual acuity, refraction, axial length, and fixation parameters. MATERIAL AND METHODS: Forty-five patients (90 eyes) were examined. All patients were divided into five groups: 1 - with dysbinocular amblyopia; 2 - with refractive amblyopia; 3 - with anisometropic amblyopia; 4 - with relative amblyopia due to congenital myopia; 5 (control) - fellow eyes without amblyopia. Aberrometry was performed using the OPD-Scan III device (Nidek, Japan). Fixation parameters were studied on the MP-3 microperimeter (Nidek, Japan). Correlation analysis was performed using Pearson's linear correlation coefficient (r). RESULTS: In amblyopia associated with congenital myopia, a significant increase in corneal and internal aberrations RMS, Total HOA, astigmatism (V) (0.65±0.26; 1.01±0.31; 4.22±1.17; -2.17±0.72; 0.86±0.3, respectively; control group - 0.44±0.19; 0.58±0.27; 1.0±0.75; -0.94±0.89; 0.47±0.65) and internal spherical aberration (0.06±0.02; control group - 0.04±0.03) was found. In dysbinocular amblyopia, a significant increase in internal aberrations Trefoil (V) and Coma (H) (0.75±0.52 and 0.17±0.35, respectively; control group - 0.05±0.28 and -0.07±0.21) was found, which correlated with a decrease in fixation density in the 2° ring (r= -0.40, r= -0.41). CONCLUSIONS: The increased level of higher-order aberrations in amblyopia associated with congenital myopia is due to the anatomical and optical features of the eyes. The increase in internal aberrations Trefoil (V) and Coma (H) in dysbinocular amblyopia is associated with a mismatch of the optical elements of the eye due to impaired fixation, i.e., it is not the cause, but the consequence of amblyopia.
Assuntos
Ambliopia , Miopia , Acuidade Visual , Humanos , Ambliopia/etiologia , Ambliopia/fisiopatologia , Ambliopia/diagnóstico , Masculino , Criança , Feminino , Miopia/complicações , Miopia/fisiopatologia , Miopia/diagnóstico , Refração Ocular/fisiologia , Aberrometria/métodos , Aberrações de Frente de Onda da Córnea/fisiopatologia , Aberrações de Frente de Onda da Córnea/etiologia , Aberrações de Frente de Onda da Córnea/diagnósticoRESUMO
Alpha-2-macroglobulin (α2-MG) is a multifunctional protein involved in neurodegeneration, inflammation and neovascularization, which are key processes in the pathogenesis of age-related macular degeneration (AMD) and proliferative diabetic retinopathy (PDR). AMD and PDR are two of the main causes of vision loss and blindness, are difficult to treat, and are generally diagnosed at the stage of irreversible changes. PURPOSE: This study estimates the activity of α2-MG in the blood serum and tears of patients with AMD and PDR in order to reveal the relation of its levels with the intensity of the pathological process in the retina. MATERIAL AND METHODS: The study included 17 patients (34 eyes) with AMD, 15 patients (30 eyes) with PDR, and 15 healthy adults (30 eyes) of the similar age. The activity of α2-MG in serum and tears was measured enzymatically using the specific substrate N-benzoyl-DL-arginine-p-nitroanilide (BAPNA). RESULTS: The activity of α2-MG in tears of patients with AMD was on the average 3.5 times higher than in healthy controls, and in patients with PDR - 1.5 times higher. Patients with AMD at the submacular fibrosis stage showed decreased α2-MG activity in tears. The activity of α2-MG in serum of patients with AMD and PDR was on the average 25% higher than in healthy persons. No correlation was revealed between serum and tear levels of α2-MG activity. CONCLUSION: This study revealed for the first time that in AMD and PDR the activity of α2-MG in tears is increased, and that in AMD the increase is higher than in PDR. An increase of α2-MG activity in serum confirms the presence of systemic inflammation. Absence of correlation between the serum and tear activity of α2-MG confirms its local origin. The high level of α2-MG activity in tears reflects the presence of an active destructive process in the retina, justifying its further investigation as a predictor of AMD and PDR course, as well as an indicator of therapy effectiveness.
Assuntos
Diabetes Mellitus , Retinopatia Diabética , Degeneração Macular , Humanos , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Inflamação , Macroglobulinas , Degeneração Macular/diagnóstico , Degeneração Macular/etiologia , Retina , Soro/metabolismoRESUMO
Local expression of genes encoding IL-1ß, IL-18, MCP-1/CCL2, PEDF, VEGF-A, and ZO-1 in the retina-retinal pigment epithelium-chorioidea tissue complex was studied in healthy rabbits and animals with simulated retinal pigment epithelium atrophy. Retinal pigment epithelium atrophy was modeled by single subretinal injection of 0.01 ml 0.9% NaCl (group 1; n=17) or 0.01 ml solution containing angiogenesis inhibitor bevacizumab in a dose of 0.025 mg (group 2; n=18). The gene expression was evaluated by reverse transcription PCR. In 27.7% cases, atrophic changes in the fundus were accompanied by a significant increase of IL-1ß gene expression and in more than 50% cases by an increase in VEGF-A and MCP-1/CCL2 mRNA levels. These factors contribute to an increase in the permeability of the blood-retina barrier and abolition of the immune privilege of the posterior eye segment, which should be taken into account when testing invasive approaches, in particular, for approbation of various options of replacement therapy with retinal pigment epithelium stem cells and development and use of neuroprotectors and drugs of targeted action.
Assuntos
Epitélio Pigmentado da Retina , Serpinas , Animais , Atrofia/genética , Atrofia/metabolismo , Atrofia/patologia , Citocinas/genética , Citocinas/metabolismo , Imunidade , Coelhos , Serpinas/genética , Serpinas/metabolismoRESUMO
PURPOSE: To develop and evaluate the results of the modified surgical technique for transplantation of retinal pigment epithelium (RPE) differentiated from human induced pluripotent stem cells (iPSC-RPE) in the form of a cell suspension into the subretinal space of rabbits with previously induced RPE atrophy. MATERIAL AND METHODS: The study was conducted on 10 New Zealand albino rabbits (20 eyes). One month after modeling RPE atrophy and retinal degeneration, rabbits were subjected to subretinal transplantation of iPSC-RPE cells in the form of a cell suspension. To prevent reflux of iPSC-RPE into the vitreal cavity, the injection site was sealed with 2-3 drops of autologous platelet-rich plasma (PRP). All rabbits underwent spectral optical coherence tomography (SOCT) and autofluorescence studies on the Heidelberg Spectralis system («Heidelberg Engineering¼, Germany). Enucleated animal eyes were studied with morphological and immunohistochemical methods. RESULTS: In this study we developed and evaluated a modified surgical technique of transplantation of iPSC-RPE in the form of a cell suspension into the subretinal space of rabbits with induced RPE atrophy. It was found that the use of PRP helps seal the defect and prevents cell suspension reflux into the vitreous cavity, effectively minimizing intra- and postoperative complications. Morphological in vivo study and examination of histological sections showed that implantable iPSC-RPEs were correctly integrated and adhered to the choroid in the surgery site. Immunohistochemical analysis involving fluorescence-marked antibodies confirmed the survival of iPSC-RPE integrated into the retina of model animals. CONCLUSION: This method improves the technology of iPSC-RPE transplantation on preclinical stages of the study, revealing new prospects in the treatment of degenerative diseases of the retina and the possibility of a personalized approach.
Assuntos
Células-Tronco Pluripotentes Induzidas , Degeneração Retiniana , Animais , Atrofia , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Coelhos , Degeneração Retiniana/diagnóstico , Degeneração Retiniana/etiologia , Degeneração Retiniana/cirurgia , Epitélio Pigmentado da Retina/patologia , Transplante de Células-Tronco/métodosRESUMO
Purpose - to comparatively analyze the wavefront aberrations and biometric parameters of the eyes with various degrees of myopia. MATERIAL AND METHODS: The study included 134 eyes of 67 patients with mild, moderate and high myopia aged 7-28 (mean age 19.3±1.5 years). The following biometric parameters were examined: anterior chamber depth (ACD), lens thickness (LT), axial length (AL), as well as corneal and total aberrations. The parameters were studied on the Galilei G6 system (Ziemer Ophthalmic Systems AG, Switzerland) and the OPD-Scan III aberrometer (Nidek, Japan). Spherical aberration (SA) was estimated as the sum of Z4+Z8+Z12. RESULTS: As the refraction increased, the root mean square higher-order aberrations (RMS HOA) also increased significantly: from 0.24±0.02 µm in mild myopia to 0.45±0.03 µm in high myopia, and in eyes with AL of ≥27.0 mm - to 0.57±0.02 µm (p=0.01). An increase in vertical tilt, vertical coma and vertical trefoil were also observed. Total SA was positive and increased in eyes with moderate myopia compared to those with low myopia (from 0.02±0.01 µm to 0.06±0.02 µm, p=0.02), which coincided with changes in the internal optics of the eye: an increase in ACD and a decrease in LT. At the same time, no differences in corneal aberrations were observed among patients with low and moderate myopia. A significant decrease of SA occurred in high myopia (from 0.06 µm in low myopia to 0.015±0.02 µm in high myopia). The average value of SA was 0.005±0.01 µm in eyes with AL of ≥27.0 mm and appeared to be negative in 40% of cases. The average value of corneal SA was negative (-0.002±0.01µm) in eyes with AL of ≥27.0 mm. This group had predominantly patients with congenital myopia. CONCLUSION: An increase of total positive SA in patients with moderate myopia compared to those with low myopia is associated with changes in the internal optics of the eye (ACD, LT). Significant increase of higher-order aberrations and decrease of SA with the transition to negative values was observed in patients with high axial myopia.
Assuntos
Miopia , Adolescente , Adulto , Biometria , Córnea/diagnóstico por imagem , Topografia da Córnea , Humanos , Miopia/diagnóstico , Refração Ocular , Testes Visuais , Acuidade Visual , Adulto JovemRESUMO
Water content in the cornea may affect the outcome of its excimer laser ablation, especially in presbyopic patients with myopic refraction. This hypothesis can be tested by scanning the cornea in the terahertz (THz) range to determine its hydration level. PURPOSE: To study the effect of hydration of the cornea determined by non-contact THz scanning and its biomechanical parameters on the results of photorefractive keratectomy (PRK) in an experiment. MATERIAL AND METHODS: PRK was performed using the Nidek EC-5000 QUEST excimer laser on 8 rabbit eyes. Corneal hydration was evaluated by determining the reflection coefficient (RC) in the THz electromagnetic radiation range before PRK, after 3-5 days, and after 1, 2, 3, and 4 months. Clinical examination included autorefractometry, assessment of corneal thickness and other anatomical and optical parameters of the anterior eye segment (Galilei G6, Ziemer Ophthalmic Systems AG 6.0.2, Switzerland), measurement of corneal hysteresis (CH) and corneal resistance factor (CRF) using the Ocular Response Analyzer (ORA; Reichert, USA), as well as tear production (Schirmer test). RESULTS: The initial water content in the cornea has a significant effect on the thickness of the removed layer, i.e. on the PRK effect, with correlation coefficient of Rs= -0.976 (p<0.01). The correlation between CH and the ablation depth is less pronounced (Rs=0.643), and CRF had no correlation with it (Rs= -0.089). Biomechanical indicators of the cornea depend on its hydration: changes in CH and CRF after excimer laser ablation qualitatively coincide with changes in RC, the correlation coefficient between RC and the initial value of CH is R= -0.619 (moderate negative correlation). CONCLUSION: THz scanning is an effective non-contact technology for monitoring corneal hydration level. The mismatch of the hypoeffect of keratorefractive excimer laser intervention planned for patients with presbyopia with the actual outcome can be caused by individual decrease in the initial water content in the cornea.
Assuntos
Miopia , Ceratectomia Fotorrefrativa , Animais , Segmento Anterior do Olho , Córnea/diagnóstico por imagem , Córnea/cirurgia , Humanos , Lasers de Excimer , Miopia/diagnóstico , Miopia/cirurgia , CoelhosRESUMO
Various animal models of atrophy of retinal pigment epithelium (RPE) are created in order to study certain aspects of geographical atrophy in humans. To study the effects of new methods of therapy, it is necessary to determine the objective functional markers of structural changes in the retina. PURPOSE: To determine the alterations in activity of the retina that characterize its remodeling in induction of RPE atrophy. MATERIAL AND METHODS: Full-field electroretinograms (ERG), pattern ERG, and multifocal ERG were recorded according to the ISCEV standards from the right eyes of twenty rabbits of the New Zealand albino breed 6-7 weeks after induction of RPE atrophy by subretinal administration of 0.9% sodium chloride or bevacizumab solution. RESULTS: Characteristic electroretinographic signs of RPE atrophy and retinal remodeling are described. Changes in ERG indicate a predominant inhibition of the functional activity of photoreceptors compared with bipolar cells, which objectively reflects an impairment of their metabolism associated with RPE pathology. With the injection of bevacizumab, a sharp weakening of the functional symbiosis of Mueller cells with bipolar cells was observed. According to pattern ERG, the function of the retinal ganglion cells was reduced. The reaction of the paired eyes after induction of RPE atrophy included a moderate decrease in the amplitude of b-wave of photopic ERG and activation of glia-neuronal relationships. CONCLUSION: Subretinal injections of 0.9% sodium chloride and bevacizumab trigger changes in the retina that reflect specific remodeling of retinal neurons of the second and third orders, which characterizes the used models of RPE atrophy.
Assuntos
Degeneração Retiniana , Epitélio Pigmentado da Retina , Animais , Atrofia , Eletrorretinografia , Coelhos , RetinaRESUMO
The article describes a clinical case of bilateral occlusion of retinal vessels in a patient with Waldenstrom's disease - a rare lymphoplasmocytic tumor of the bone marrow characterized by a complex of syndromes, among which the syndrome of blood hyperviscosity dominates. Comprehensive clinical, instrumental and laboratory examinations revealed that besides the syndrome of blood hyperviscosity the patient also had loci of cerebral ischemia (according to magnetic resonance imaging), ocular hypoperfusion with severe deficiency of retinal and choroidal blood flow (according to Doppler methods) indicating the presence of ocular ischemic syndrome. Since bilateral occlusion of retinal vessels without concomitant vascular and/or systemic pathology is rare, patients with such diagnosis should be referred to a hematologist.
Assuntos
Vasos Retinianos , Macroglobulinemia de Waldenstrom , Corioide , Hemodinâmica , Humanos , RetinaRESUMO
Intravitreal drug administration is a procedure that has become widespread in modern ophthalmology. However, there is no global consensus on certain aspects of this manipulation, and practitioners feel the need for guidelines. In the Russian Federation, until now, such a document was not available. The expert council on diseases of the retina and optic nerve of All-Russian public organization «Association of Ophthalmologists¼, with participation of invited specialists, has studied and analyzed the existing foreign guidelines for performing intravitreal injections, as well as the regulatory framework in Russia. As a result, this Protocol was developed and approved for use in the healthcare system of the Russian Federation. The document regulates the requirements for specialists and organizations, the conditions for performing the procedure and the necessary material resources and presents an algorithm for performing intravitreal drug administration, a patient examination check-list for various conditions of the procedure, as well as parameters for evaluating and monitoring the quality of the procedure.
Assuntos
Oftalmologistas , Doenças do Nervo Óptico , Preparações Farmacêuticas , Consenso , Humanos , Retina , Federação RussaRESUMO
Multicolor scanning laser ophthalmoscopy (multicolor SLO) is a new informative method of eye fundus visualization. The method is based on synchronously obtaining three separate confocal images with monochromatic laser sources - blue (488 nm), green (515 nm) and infrared (820 nm), which are then combined into one in the Multicolor mode. PURPOSE: To evaluate the informative value of multicolor SLO in a complex examination of patients with severe proliferative diabetic retinopathy (PDR). MATERIAL AND METHODS: A total of 46 patients (62 eyes) aged 19 to 75 years with severe PDR was examined. All patients had massive growth of proliferative tissue on the eye fundus, which caused traction deformation and/or retinal detachment in the posterior pole. Optical mediums of the eyes were sufficiently transparent to obtain high quality images. All patients underwent color photo-registration of the fundus, fluorescein angiography (FA), optical coherence tomography (OCT) and multicolor SLO under drug-induced mydriasis. RESULTS: Pseudo-volumetric images obtained with multicolor SLO allow visualization of of preretinal proliferative membranes and their structure, the degree of their vascularization, the anatomical features of their attachment to retina, and the occluded vessels on fundus periphery. Being an additional option on scanning laser ophthalmoscope, the technique does not require special equipment, which enables several separate examinations, including OCT and FA, to be performed on a single device. CONCLUSION: Multicolor SLO is a promising new method of visualizing structures of the eye fundus and can be successfully used in complex diagnostics, monitoring and preoperative preparation of patients with severe PDR.
Assuntos
Retinopatia Diabética , Adulto , Idoso , Angiofluoresceinografia , Fundo de Olho , Humanos , Pessoa de Meia-Idade , Oftalmoscopia , Tomografia de Coerência Óptica , Adulto JovemRESUMO
According to various studies, treatment adherence of patients with primary open-angle glaucoma ranges from 5% to 80% and significantly influences the effectiveness of the therapy. Some authors report higher levels of adherence in patients receiving preservative-free medications. PURPOSE: To study the influence of treatment adherence in patients receiving preservative-free and preserved medications on the progression of primary open-angle glaucoma (POAG). MATERIAL AND METHODS: This prospective multicenter non-interventional study was conducted in clinical setting and included 504 patients with primary open-angle glaucoma receiving drug therapy; 51 ophthalmologist was involved in the management of patients' diaries. RESULTS: The percentage of patients who did not reach target IOP was three times lower in the group with high adherence, in comparison to patients with medium and low adherence (7% against 22%, respectively). Development of side effects was one of the factors influencing treatment adherence, their rates and expressiveness were much lower in the preservative-free group compared with the group receiving preserved medication (13.9% against 35.4%). The rate of patients who did not reach target IOP was two times lower in the group of preservative-free medication (10% against 21%). CONCLUSION: The study confirms that preservative-free glaucoma medication promotes higher adherence to treatment in clinical setting predominantly due to the reduction of quantity and severity of side effects leading to treatment gaps, which results in increased effectiveness and better stabilization of glaucoma.
Assuntos
Glaucoma de Ângulo Aberto , Pressão Intraocular , Anti-Hipertensivos , Humanos , Conservantes Farmacêuticos , Estudos Prospectivos , Cooperação e Adesão ao TratamentoRESUMO
PURPOSE: To compare the wavefront and accommodation parameters without correction and in soft contact lenses (SCL) in natural and cycloplegic conditions in eyes with myopia and hyperopia. MATERIAL AND METHODS: A total of 142 myopic (mean -5.6±1.4 D) and 48 hyperopic (mean +3.5±1.1 D) eyes were examined in 95 patients aged 5-32 years (mean age 16.9±0.9 years) to compare the wavefront aberrations without correction and with different SCL before and after cycloplegia (two drops of cyclopentolate hydrochloride 1%). The device was set up for 4 mm zone for both narrow and wide pupils. To compare the accommodation parameters under different correction conditions, 85 patients aged 8-23 years (mean age 14.9±0.6 years) with average myopia of (-)5.27±1.4D (123 eyes) and average hyperopia of +3.53±1.2 D (46 eyes) were chosen from the study group. Among the measured parameters are objective accommodative response (OAR), relative accommodation reserves (RAR), pseudoaccumulation amplitude (PA), higher-order aberrations: RMSHOAs, 6-9 Trefoil, 7-8 Coma, spherical aberration (SA). RESULTS: In myopic eyes with SCL Coma 7 decreases, Coma 8 increases with transition to positive values, and Trefoil 9 increases. In hyperopic eyes, trefoil 6 decreases, Coma 7-8 go negative. In myopic or hyperopic eyes with SCL, SA goes from positive to negative. In both myopia and hyperopia, accommodation and PA rates are higher in SCL than in glasses. CONCLUSION: SCL change certain wavefront parameters for myopia and hyperopia in different ways. The accommodation parameters in SCL are elevated in both myopia and hyperopia. The negative spherical aberration induced by contact lenses improves the accommodative response. The revealed features should be considered in the development of correction methods that target refractogenesis.
Assuntos
Acomodação Ocular , Lentes de Contato Hidrofílicas , Hiperopia , Miopia , Adolescente , Adulto , Criança , Pré-Escolar , Olho , Humanos , Hiperopia/terapia , Miopia/terapia , Refração Ocular , Adulto JovemRESUMO
Today, diabetic macular edema (DME) is still one of the main causes of vision loss in patients with diabetes. PURPOSE: To identify changes in the ocular blood flow and microvascular network of the macular zone in patients with DME after antiangiogenic therapy. MATERIAL AND METHODS: In the course of the study, 25 patients (50 eyes) with monolateral clinically significant DME aged 67.5±3.85 years were examined. Control group consisted of 75 healthy subjects (150 eyes). All patients underwent ultrasound examination of the eyes and orbits (in Color Doppler Imaging (CDI) and Pulse-Doppler modes) and OCT-angiography (OCT-A) before the intravitreal injection of ranibizumab, as well as 3 days, 2 weeks, and 1 month after the treatment. RESULTS: According to OCT-A, the initial values of microvascular network parameters were significantly below the norm (p<0.05). After intravitreal ranibizumab injection (IRI), no significant changes in the density of microcapillaries or in the parameters of foveal avascular zone (FAZ) were recorded. However, a transient increase of the FAZ area was revealed 2 weeks after the injection, as well as an increase of microcapillaries density in the central quadrant together with a decrease of density in the peripheral quadrants 1 month after IRI. By the end of the follow-up period, a decrease in the initially raised maximum systolic velocity (Vsyst) and resistance index (RI) in the ophthalmic artery (OA) of the affected eye were documented. Additionally, an increase in Vsyst and 2-fold increase in end-diastolic velocity (Vdiast), as well as a decrease in RI in the central retinal artery (CRA) on the affected and paired eyes were detected. CONCLUSION: The study revealed no negative effects of the angiogenesis inhibitor ranibizumab on retinal microcirculation or ocular blood flow. The registered changes in blood flow may indicate improvement of hemodynamic parameters after resorption of macular edema.
Assuntos
Inibidores da Angiogênese , Retinopatia Diabética , Edema Macular , Idoso , Inibidores da Angiogênese/uso terapêutico , Hemodinâmica , Humanos , Injeções Intravítreas , Edema Macular/tratamento farmacológico , Microcirculação , Pessoa de Meia-Idade , Ranibizumab , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular , Acuidade VisualRESUMO
Small choroidal melanoma is a malignant tumor that is prone to early metastasis, its amelanotic form is often similar to circumscribed choroidal hemangioma. The main attribute for tumor identification is its vascularization, which is the target of various examination methods. Optical coherence tomography angiography (OCTA) has not been previously used in complex diagnostics of early choroidal melanoma and circumscribed choroidal hemangioma for detection of tumor vessels and the nature of their branching, as well as for vessel caliber comparison. Purpose to examine vascularization of early uveal melanoma and circumscribed choroidal hemangioma by optical coherence tomography angiography. MATERIAL AND METHODS: The study included 23 patients with early choroidal melanoma (13 subjects) and circumscribed choroidal hemangioma (10 subjects) that were examined by optical coherence tomography angiography. According to ultrasound investigation, mean tumor prominence was 1.1±0.3 mm, mean base diameter - 8.1±0.6 mm. RESULTS: Optical coherence tomography angiography in 13 patients with small choroidal melanoma revealed presence of a neovascular component localized under retinal pigment epithelium (RPE) that had marginal avascular zone corresponding to the tumor slope. The loop-like shape of tumor vessels with numerous twists and interweaving was noted under retinal vessels. A tree-shaped neovascular component with large-caliber vessels in the form of a tree trunk with multiple branches extending from it was seen under RPE in 4 cases with circumscribed choroidal hemangioma; diffuse vascularization in the form of numerous tiny tortuous vascular branches was seen in 6 patients. CONCLUSION: Optical coherence tomography angiography allows detection of tumor`s own vessels with characteristics of their vascularization in early choroidal melanoma and circumscribed choroidal hemangioma. Increasing the frequency of detection of tumor`s own vessels will make possible early differential diagnostics of a malignant or benign tumor and will help establish adequate conserving therapy.
Assuntos
Neoplasias da Coroide , Hemangioma , Melanoma , Neoplasias da Coroide/diagnóstico por imagem , Angiofluoresceinografia , Hemangioma/diagnóstico por imagem , Humanos , Melanoma/diagnóstico por imagem , Tomografia de Coerência Óptica , Neoplasias UveaisRESUMO
AIM: to comparatively investigate accommodation, pseudoaccommodation, and higher-order aberrations in children and young adults with myopia and hyperopia. MATERIAL AND METHODS: A total of 39 myopic (the mean error of (-)5.2±1.5 diopters) and 53 hyperopic (the mean error of (+)3.1±1.15 diopters) eyes of 46 patients aged 5-20 years (11.6±0.6 years on average) were enrolled. Examination included evaluation of the objective accommodative response, relative accommodation reserves, pseudoaccommodation volume (calculated as the difference between the (+)3.0-diopter lens that is necessary for cycloplegic reading at a 33-cm distance and the weakest possible plus lens that enables reading), and higher-order aberrations (HOA), particularly the root mean square (RMS) value, vertical and horizontal trefoil, vertical and horizontal coma (coma7, coma8), and spherical aberration (SA). RESULTS: Both objective and subjective parameters of accommodation were reliably lower in myopia as compared to hyperopia, while wavefront aberrations (RMS HOA, vertical trefoil, coma7) and pseudoaccommodation - reliably greater. SA was found to be reliably more pronounced in those myopes, who demonstrated larger volume of pseudoaccommodation. At the same time, there was a mismatch in wavefront parameters of myopes and hyperopes at different levels of accommodation and pseudoaccommodation. In myopic eyes, vertical trefoil decreased down to negative values as the accommodative response improved. In contrast to that, in hyperopic eyes with large volume of pseudoaccommodation, SA decreased below zero. CONCLUSION: Myopia has been shown to be associated with reduced accommodation parameters as well as stronger HOA and pseudoaccommodation. Wavefront and accommodation parameters interrelations differ in myopic and hyperopic eyes. The nuances revealed should be taken into account when developing correction methods that purposefully influence refractogenesis.
Assuntos
Aberrometria/métodos , Aberrações de Frente de Onda da Córnea , Hiperopia , Miopia , Acomodação Ocular/fisiologia , Adolescente , Adulto , Criança , Aberrações de Frente de Onda da Córnea/diagnóstico , Aberrações de Frente de Onda da Córnea/fisiopatologia , Feminino , Humanos , Hiperopia/diagnóstico , Hiperopia/fisiopatologia , Masculino , Miopia/diagnóstico , Miopia/fisiopatologia , Estatística como AssuntoRESUMO
AIM: To study the effect of resveratrol on ocular blood flow in vivo in healthy rats and those that underwent retinal ischemia/reperfusion. MATERIAL AND METHODS: The experimental study was performed on 40 Wistar rats (40 eyes). For ocular blood flow evaluation, color Doppler imaging (CDI), power Doppler (PD), and pulsed-wave spectral Doppler ultrasonography were performed using the Voluson E8 Expert ultrasonic diagnostic system (GE Healthcare). All rats were given resveratrol per os for 2 months of the study. Retinal ischemia/reperfusion injury was induced by a subconjunctival injection of endothelin-1. The control group included 10 intact animals. RESULTS: Signs of ischemic damage of the anterior and posterior eye segments were less pronounced in rats that were given resveratrol during both pre-ischemic (30 days) and post-ischemic (30 days) periods of follow-up. There was also a statistically significant increase in the peak systolic and end diastolic velocity of blood flow as well as a decrease in the resistive index of retrobulbar arteries in those rats that underwent ischemia/reperfusion as compared to the controls. CONCLUSION: Long-term resveratrol use (2 months) has proved effective in improving ocular blood flow in a rat model of retinal ischemia/reperfusion injury.
Assuntos
Olho , Artéria Oftálmica , Traumatismo por Reperfusão , Artéria Retiniana , Estilbenos/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Antioxidantes/farmacologia , Olho/irrigação sanguínea , Olho/metabolismo , Artéria Oftálmica/efeitos dos fármacos , Artéria Oftálmica/fisiopatologia , Ratos , Ratos Wistar , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/mortalidade , Traumatismo por Reperfusão/fisiopatologia , Resveratrol , Artéria Retiniana/efeitos dos fármacos , Artéria Retiniana/fisiopatologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Tempo , Resultado do Tratamento , Ultrassonografia Doppler em Cores/métodos , Vasodilatadores/farmacologiaRESUMO
AIM: to evaluate and compare the effect of topical superoxide dismutase (SOD), which is an antioxidant enzyme, dexamethasone, and a combination of these on the course of experimental uveitis in rabbits as well as biochemical parameters of aqueous and vitreous humor. MATERIAL AND METHODS: Acute uveitis was induced in 16 rabbits by a double injection (subcutaneous and intravitreal) of normal horse serum. Of them 12 animals, divided into 3 groups of 4 each, received topical SOD, dexamethasone, or both daily for 7 days. The remaining 4 rabbits (8 eyes) were treated with placebo and, thus, constituted the control group. On day 8 the following parameters were measured in aqueous humor: protein concentration, antioxidant activity, SOD activity, α2-macroglobulin level, and leukocyte number. Total protein and albumin levels in vitreous humor were also determined. RESULTS: The effects of SOD and dexamethasone instillations were considered similar in many parameters. However, SOD was associated with a greater increase in antioxidant activity and a greater decrease in aqueous humor leukocytes, while dexamethasone was more effective in decreasing aqueous humor α2-macroglobulin and vitreous humor protein and albumin. The substances had a synergistic effect on iridal edema as well as aqueous humor leukocyte number and α2-macroglobulin level. CONCLUSION. Adding SOD to the complex therapy of uveitis results in lower inflammation intensity and enhanced dexamethasone effect.
Assuntos
Humor Aquoso/metabolismo , Dexametasona/administração & dosagem , Superóxido Dismutase/administração & dosagem , Uveíte/tratamento farmacológico , Animais , Humor Aquoso/efeitos dos fármacos , Fenômenos Bioquímicos/efeitos dos fármacos , Modelos Animais de Doenças , Quimioterapia Combinada , Sequestradores de Radicais Livres/administração & dosagem , Glucocorticoides/administração & dosagem , Instilação de Medicamentos , Coelhos , Uveíte/diagnóstico , Corpo Vítreo/efeitos dos fármacos , Corpo Vítreo/metabolismoRESUMO
The article presents an analysis of Russian eye care performance indicators based on federal and sector statistics over the recent years provided by the Ministry of Health of the Russian Federation, that is the incidence of eye diseases, eye care equipment provision, inpatient and outpatient volumes. Legal acts of the Russian Federation on health system in general and eye care in particular were taken into consideration when preparing the section on organizational matters. Problems of human resources, efficiency of specialists' time management, hospital beds use, and administrative issues in particular regions and Russia as a whole are discussed.
Assuntos
Atenção à Saúde/organização & administração , Oftalmopatias , Oftalmologia , Atenção à Saúde/estatística & dados numéricos , Eficiência Organizacional , Oftalmopatias/diagnóstico , Oftalmopatias/epidemiologia , Oftalmopatias/terapia , Regulamentação Governamental , Prioridades em Saúde , Recursos em Saúde/estatística & dados numéricos , Administração de Serviços de Saúde/legislação & jurisprudência , Administração de Serviços de Saúde/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde , Humanos , Incidência , Oftalmologia/métodos , Oftalmologia/organização & administração , Federação RussaRESUMO
OBJECTIVE: to study the influence of experimental uveitis on those biochemical parameters of aqueous humor that reflect inflammation acuity as well as local antioxidant and local antiproteolytic activity; to study the effect of topical superoxide dismutase (SOD) on the clinical course of uveitis and ocular metabolism. MATERIAL AND METHODS: Acute uveitis was induced in rabbits by a double injection (subcutaneous and intravitreal) of normal horse serum. The following parameters of aqueous humor were measured: protein concentration, antioxidant activity, SOD activity, alpha2-macroglobulin level, total nitrates and nitrites, and leukocyte number. Clinical assessment and histopathological study were performed. RESULTS: It was found that uveitis is associated with a statistically significant increase in protein concentration, leukocyte number, SOD activity, and alpha2-macroglobulin level in aqueous humor as well as a decrease in anti-hydroxyl radical activity. SOD instillations contributed to the reduction of the listed parameters and improvement of the antioxidant activity. Clinical presentations of uveitis also became less pronounced. CONCLUSION: SOD instillations for oxidative stress correction help reduce clinical presentations of uveitis, which is confirmed by biochemical examination.
Assuntos
Biomarcadores/metabolismo , Superóxido Dismutase , Uveíte , alfa-Macroglobulinas/metabolismo , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Humor Aquoso/metabolismo , Córnea/patologia , Modelos Animais de Doenças , Estresse Oxidativo , Coelhos , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia , Resultado do Tratamento , Uveíte/tratamento farmacológico , Uveíte/metabolismo , Uveíte/patologiaRESUMO
23 infants (46 eyes) with zone I retinopathy of prematurity (ROP) were examined. Zone I ROP is characterized with distinctive clinical presentation, course, prognosis and treatment results. Coagulation of retina in active I zone ROP showed efficacy in 70%: in posterior ROP - 56,3%, in anterior ROP - 79%. Surgery was performed in 12 eyes with stage 4a-5 ROP. Lens-sparing vitrectomy at gestational age of 44-45 weeks resulted in partial or total reattachment of retina that was achieved in 5 eyes with 4a-4b stage ROP. In the other cases the surgery played an eye preserving role. Late functional results are indicative of multifactorial pathogenesis of visual function impairment in infants with I zone ROP.