Caracterización de las lesiones compresivas de la vía visualanterior / Characterization of Compressive Lesions of the Anterior VisualPathway

Objetivo: Determinar las características clínico-epidemiológicas de los pacientes diagnosticados con lesiones compresivas de la vía visual anterior. Métodos: Se realizó un estudio descriptivo transversal durante el período comprendido entre mayo de 2018 y marzo de 2020 con 41 pacientes con diagnóstico de síndrome compresivo de la vía visual anterior atendidos en el Servicio de Neuroftalmología del Instituto Cubano de Oftalmología "Ramón Pando Ferrer". Resultados: La mayor frecuencia en cuanto a síntomas fue la disminución progresiva de la visión central. Se encontraron lesiones de tipo tumoral en 39 pacientes para el 95,1 por ciento. Los defectos hemianópticos se detectaron en el campo visual del 45 por ciento de la muestra y el 33 por ciento presentó disminución difusa de la sensibilidad retiniana. Conclusiones: La mayoría de los pacientes fueron del sexo femenino en edades medias de la vida. Predominaron las lesiones tumorales sobre las vasculares. Los macroadenomas de hipófisis y los meningiomas fueron las etiologías más frecuentes y el sitio de compresión más encontrado fue el quiasma óptico. Se detectó disminución del grosor del complejo de células ganglionares maculares en la tomografía de coherencia óptica de la mayoría de los enfermos(AU)

Objective: To determine the clinical-epidemiological characteristics of patients diagnosed with compressive lesions of the anterior visual pathway. Methods: A cross-sectional descriptive study was conducted during the period from May 2018 to March 2020 with 41 patients diagnosed with compressive syndrome of the anterior visual pathway attended at the Neurophthalmology Service of the Cuban Institute of Ophthalmology "Ramón Pando Ferrer". Results: The most frequent symptom was the progressive decrease of central vision. Tumor type lesions were found in 39 patients for 95.1 percent. Hemianoptic defects were detected in the visual field of 45 percent of the sample and 33 percent presented diffuse decrease of retinal sensitivity. Conclusions: The majority of patients were female at middle ages of life. Tumor lesions predominated over vascular lesions. Pituitary macroadenomas and meningiomas were the most frequent etiologies and the most frequent site of compression was the optic chiasm. Decreased thickness of the macular ganglion cell complex was detected in the optical coherence tomography of most of the patients(AU)

Representations of object animacy and real-world size in the ventral visual pathway / 生理学报

How the brain perceives objects and classifies perceived objects is one of the important goals of visual cognitive neuroscience. Previous research has shown that when we see objects, the brain's ventral visual pathway recognizes and classifies them, leading to different ways of interacting with them. In this paper, we summarize the latest research progress of the ventral visual pathway related to the visual classification of objects. From the perspective of the neural representation of objects and its underlying mechanisms in the visual cortex, we summarize the current research status of the two important organizational dimensions of object animacy and real-world size, provide new insights, and point out the direction of further research.

Grating visual acuity impairment assessed by sweep visually evoked potentials in children with optic pathway tumors unable to perform optotype acuity tests / Deficiência na acuidade visual de grades avaliada pelos potenciais visuais evocados de varredura em crianças com tumores da via óptica incapazes de informar a acuidade de optotipos

ABSTRACT Purpose: To determine visual impairment due to optic pathway tumors in children unable to perform recognition acuity tests. Methods: Grating visual acuity scores, in logMAR, were obtained by sweep visually evoked potentials (SVEP) in children with optic pathway tumors. The binocular grating visual acuity deficit was calculated by comparison with age-based norms and then assigned to categories of visual impairment as mild (from 0.10 to 0.39 logMAR), moderate (from 0.40 to 0.79 logMAR), or severe (≥0.80 logMAR). Interocular differences were calculated by subtraction and considered increased if >0.10 logMAR. Results: The participants were 25 children (13 boys; mean ± SD age, 35.1 ± 25.9 months; median age, 32.0 months) with optic pathway tumors (24 gliomas and 1 embryonal tumor), mostly located at the hypothalamic-chiasmatic transition (n=21; 84.0%) with visual abnormalities reported by parents (n=17; 68.0%). The mean grating acuity deficit was 0.60 ± 0.36 logMAR (median, 0.56 logMAR). Visual impairment was detected in all cases and was classified as mild in 10 (40.0%), moderate in 8 (32.0%), and severe in 7 (28.0%) children, along with increased interocular differences (>0.1 logMAR) (n=16; 64.0%). The remarkable ophthalmological abnormalities were nystagmus (n=17; 68.0%), optic disc cupping and/or pallor (n=13; 52.0%), strabismus (n=12; 48.0%), and poor visual behavior (n=9; 36.0%). Conclusion: In children with optic pathway tumors who were unable to perform recognition acuity tests, it was possible to quantify visual impairment by sweep-visually evoked potentials and to evaluate interocular differences in acuity. The severity of age-based grating visual acuity deficit and interocular differences was in accordance with ophthalmological abnormalities and neuroimaging results. Grating visual acuity deficit is useful for characterizing visual status in children with optic pathway tumors and for supporting neuro-oncologic management.(AU)

RESUMO Objetivo: Determinar o grau de deficiência visual em crianças com tumores da via óptica incapazes de informar a acuidade visual de reconhecimento. Método: A acuidade visual de grades, em logMAR, foi estimada por potenciais visuais evocados de varredura em crianças com tumores das vias ópticas. O déficit da acuidade visual de grades binocular foi calculado em relação ao valor mediano normativo esperado para a idade e a deficiência visual, classificada como leve (0,10 a 0,39 logMAR), moderada (0,40 a 0,79 logMAR) ou grave (≥0,80 logMAR). Diferenças inter-oculares foram calculadas por subtração e consideradas aumentadas se >0,10 logMAR. Resultados: Foram avaliadas 25 crianças (13 meninos; média de idade ± DP=35,1± 25,9 meses; mediana=32,0 meses) com tumores da via óptica (24 gliomas e 1 tumor embrionário) localizados particularmente na transição hipotalâmico-quiasmática (n=21; 84,0%) e com anormalidades visuais detectadas pelos pais (n=17; 68,0%). A média do déficit da acuidade de grades foi 0,60 ± 0,36 logMAR (mediana=0,56 logMAR). Observou-se deficiência visual leve em 10 (40,0%), moderada em 8 (32,0%) e grave em 7 (28,0%), além de aumento da diferença interocular da acuidade visual (n=16; 64,0%). As principais alterações oftalmológicas encontradas foram: nistagmo (n=17; 68,0%), aumento da escavação do disco óptico e/ou palidez (n=13; 52,0%), estrabismo (n=12; 48,0%) e comportamento visual pobre (n=9; 36,0%). Conclusão: Em crianças com tumor da via óptica e incapazes de responder aos testes de acuidade visual de reconhecimento, foi possível quantificar deficiência visual por meio dos potenciais visuais evocados de varredura e avaliar a diferença interocular da acuidade visual de grades. A gravidade do déficit da acuidade visual de grades relacionado à idade e a diferença interocular da acuidade visual de grades foram congruentes com alterações oftalmológicas e neuroimagem. O déficit da acuidade visual de grades foi útil à caracterização do estado visual em crianças com tumores da via óptica e ao embasamento da assistência neuro-oncológica.(AU)

Topography of Visual Features in the Human Ventral Visual Pathway / 神经科学通报·英文版

Visual object recognition in humans and nonhuman primates is achieved by the ventral visual pathway (ventral occipital-temporal cortex, VOTC), which shows a well-documented object domain structure. An on-going question is what type of information is processed in the higher-order VOTC that underlies such observations, with recent evidence suggesting effects of certain visual features. Combining computational vision models, fMRI experiment using a parametric-modulation approach, and natural image statistics of common objects, we depicted the neural distribution of a comprehensive set of visual features in the VOTC, identifying voxel sensitivities with specific feature sets across geometry/shape, Fourier power, and color. The visual feature combination pattern in the VOTC is significantly explained by their relationships to different types of response-action computation (fight-or-flight, navigation, and manipulation), as derived from behavioral ratings and natural image statistics. These results offer a comprehensive visual feature map in the VOTC and a plausible theoretical explanation as a mapping onto different types of downstream response-action systems.

Alucinosis peduncular: descripción de un caso y revisión del tema / Peduncular hallucinosis: a case report and topic review / Alucinose peduncular: descrição de um caso e revisão do assunto

La alucinosis peduncular es el término utilizado para describir una forma rara de alucinaciones visuales complejas, vívidas, coloridas y generalmente recurrentes que ocurren en relación a lesiones del tronco encefálico y el tálamo. Es una patología infrecuente y su fisiopatología es controvertida. Describimos el caso de una mujer de 38 años con alucinosis peduncular asociada a compresión extrínseca del tronco encefálico secundaria a un schwannoma vestibular. Analizamos las características clínicas y los mecanismos fisiopatológicos subyacentes.

Peduncular hallucinosis is a clinical condition characterized by vivid, colorful, complex visual hallucinations that often recur in time and are described in association with midbrain and thalamic lesions. It is a rare phenomenon and its precise pathophysiology is unknown. We describe the case of a 38-year-old woman who developed peduncular hallucinosis in relation to extrinsic compression of the midbrain secondary to a vestibular schwannoma. Clinical features and underlying pathophysiological mechanisms are discussed.

A alucinose peduncular é o termo usado para descrever uma forma rara de alucinações visuais complexas, vívidas, coloridas e geralmente recorrentes que ocorrem em relação às lesões do tronco encefálico e do tálamo. É uma patologia infreqüente e sua fisiopatologia é controversa. Descrevemos o caso de uma mulher de 38 anos de idade com alucinose peduncular associada à compressão extrínseca do tronco encefálico secundária ao schwannoma vestibular. Analisamos as características clínicas e os mecanismos fisiopatológicos subjacentes.

Molecular guidance cues in the development of visual pathway

70%-80% of our sensory input comes from vision. Light hit the retina at the back of our eyes and the visual information is relayed into the dorsal lateral geniculate nuclei (dLGN) and primary visual cortex (V1) thereafter, constituting the image-forming visual circuit. Molecular cues are one of the key factors to guide the wiring and refinement of the image-forming visual circuit during pre- and post-embryonic stages. Distinct molecular cues are involved in different developmental stages and nucleus, suggesting diverse guidance mechanisms. In this review, we summarize molecular guidance cues throughout the image-forming visual circuit, including chiasm determination, eye-specific segregation and refinement in the dLGN, and at last the reciprocal connections between the dLGN and V1.

Optical Coherence Tomography versus Visual Evoked Potentials for Detecting Visual Pathway Abnormalities in Patients with Neuromyelitis Optica Spectrum Disorder

BACKGROUND AND PURPOSE: Optical coherence tomography (OCT) and visual evoked potentials (VEPs) can be used to detect optic neuritis (ON). However, the comparative sensitivities of OCT and VEPs for detecting ON in neuromyelitis optica spectrum disorder (NMOSD) are unclear, and so we assessed these sensitivities. METHODS: This cross-sectional study included 73 patients with aquaporin-4 antibody-seropositive NMOSD, and 101 eyes with ON. The clinical characteristics, visual acuity (VA), Expanded Disability Status Scale (EDSS) scores, OCT peripapillary retinal nerve fiber layer (RNFL) thickness, and VEPs of the patients were evaluated. RESULTS: OCT and VEPs were abnormal in 68% and 73% of eyes with a history of ON, respectively, and in 2% and 9% of eyes without ON. Test sensitivities were influenced by the number of ON episodes: the OCT RNFL thickness and VEPs were abnormal in 50% and 67% of the eyes with first-ever ON episode, respectively (p=0.041), with the combination of both tests detecting abnormalities in up to 75% of the eyes. The sensitivities of the OCT RNFL thickness and VEPs increased to 95% and 83%, respectively, after the second or subsequent ON episode (p=0.06), with the combination of both tests detecting abnormalities in 95% of cases. The OCT RNFL thickness and VEP latency/amplitude were correlated with EDSS scores and VA. CONCLUSIONS: VEPs were superior for detecting subclinical or first-ever ON, while OCT was better for detecting eyes with multiple ON episodes. The correlations of OCT and VEPs with clinical disability measures indicate that these tests are potential markers of the disease burden in NMOSD.

The Antidepressant Effect of Light Therapy from Retinal Projections / 神经科学通报·英文版

Observations from clinical trials have frequently demonstrated that light therapy can be an effective therapy for seasonal and non-seasonal major depression. Despite the fact that light therapy is known to have several advantages over antidepressant drugs like a low cost, minimal side-effects, and fast onset of therapeutic effect, the mechanism underlying light therapy remains unclear. So far, it is known that light therapy modulates mood states and cognitive functions, involving circadian and non-circadian pathways from retinas into brain. In this review, we discuss the therapeutic effect of light on major depression and its relationship to direct retinal projections in the brain. We finally emphasize the function of the retino-raphe projection in modulating serotonin activity, which probably underlies the antidepressant effect of light therapy for depression.

A Case Report of Occipital Lobe Epilepsy and Related Optical Coherence Tomography Findings

PURPOSE: In the present case report, visual pathway damage confirmed by retinal ganglion cell layer (GCL) damage on optical coherence tomography (OCT) in occipital lobe epilepsy was described. CASE SUMMARY: A 25-year-old female with idiopathic generalized epilepsy developed visual blurring followed by a generalized seizure. On brain magnetic resonance imaging (MRI), very subtle changes of the cortex in the left parietooccipital lobe were observed. Two days after the attack, even after the disappearance of epileptiform wave on electroencephalogram (EEG), visual acuity in both eyes was 0.5 and a perimetry revealed nearly complete visual defect in both eyes. OCT showed severe thinning of GCL and mild thinning of retinal nerve fiber layer (RNFL). No additional seizure attack occurred thereafter. One month after the attack, her visual acuity was recovered to 1.0 in both eyes and her left visual hemifield defect was recovered. However, even 6 months after the attack, her right visual hemifield defect and GCL damage persisted in both eyes. CONCLUSIONS: We reported a case in which the visual pathway damage caused by occipital lobe epilepsy was identified using OCT, despite very subtle changes in brain imaging. This case indicated GCL thinning is an objective and prognostic index for the irreversible visual field defect in occipital lobe epilepsy.

An Unruptured Anterior Communicating Artery Aneurysm Presenting with Left Homonymous Hemianopsia: A Case Report

Unruptured cerebral aneurysms sometimes present with visual symptomsdue to compression of the visual pathways. However, until now, unruptured anterior communicating artery (ACoA) aneurysms presenting visual field defects have been extremely rare. The authors report the case of a 51-year-old woman who presented with left homonymous hemianopsia. Radiological findings demonstrated an ACoA aneurysm filled with thrombus, that was compressing the optic chiasm and post-chiasmal tract. The patient underwent clipping of the aneurysm, which resolved the visual field defect. In cases of visual field defects, an ACoA aneurysm should be included in the differential diagnosis.

Pattern-reversal visual evoked potentials as a diagnostic tool for ocular malingering / Potenciais visuais evocados por padrões reversos como uma ferramenta diagnóstica de simulação

ABSTRACT Purpose: To investigate the contributions of transient pattern-reversal visual evoked potentials in the diagnosis of ocular malingering at a Brazilian university hospital. Methods: Adult patients with suspected malingering in one or both eyes were referred for visual evoked potential testing. Data from patients' medical records were reviewed and analyzed retrospectively. Data analysis included the distance optotype visual acuity based on a ETDRS retro-illuminated chart and the transient pattern-reversal visual evoked potential parameters of latency (milliseconds) and amplitude (microvolts) for the P100 component, using checkerboards with visual subtenses of 15' and 60'. Motivations for malingering were noted. Results: The 20 subjects included 11 (55%) women. Patient ages ranged from 21 to 61 years (mean= 45.05 ± 11.76 years; median= 49 years). In 8 patients (6 women), both eyes exhibited reduced visual acuity with normal pattern-reversal visually evoked potential parameters (pure malingerers). The remaining 12 patients (7 men) exhibited reduced vision in only 1 eye, with simulated reduced vision in the contralateral eye (exaggerators). Financial motivation was noted in 18 patients (9 men). Conclusion: Normal pattern-reversal visually evoked potential parameters with suspected ocular malingering were observed in a 20 patient cohort. This electrophysiological technique appeared to be useful as a measure of visual pathway integrity in this specific population.

RESUMO Objetivo: Investigar a contribuição dos potenciais visuais evocados por padrões reversos no diagnóstico de simulação de baixa de visão em um hospital universitário do Brasil. Métodos: Um grupo de pacientes adultos com suspeita de simulação de baixa de visão em um ou ambos os olhos foi avaliado e os dados analisados retrospectivamente. Foram medidos: acuidade visual de optotipos informada para longe utilizando a tabela ETDRS, parâmetros dos potenciais visuais evocados por padrões reversos de latência (milissegundos) e amplitude (microvolts) para o componente P100 com estímulos de ângulos visuais de 15' e 60'. A motivação do paciente para a simulação foi anotada. Resultados: Os participantes foram 20 indivíduos com 11 (55%) do sexo feminino. A idade variou de 21 a 61 anos (média= 45,05 ± 11,76 anos; mediana= 49 anos). Em 8 pacientes (6 mulheres) ambos os olhos tinham acuidade visual reduzida com parâmetros dos potenciais visuais evocados por padrão reverso normais para ambos os olhos (simuladores puros). Uma subsérie separada de 12 pacientes (7 homens) tinha visão reduzida em apenas um olho e estavam simulando redução da visão no outro olho (exacerbadores). A motivação financeira foi observada em 18 pacientes (9 homens). Conclusões: Parâmetros dos potenciais visuais evocados por padrões reversos normais foram encontrados neste grupo de 20 pacientes com suspeita de simulação. Esta técnica eletrofisiológica pode ser útil como uma medida da integridade do sistema visual nesta população de doentes.

Ability of Mn(2+) to Permeate the Eye and Availability of Manganese-enhanced Magnetic Resonance Imaging for Visual Pathway Imaging via Topical Administration / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Manganese-enhanced magnetic resonance imaging (MEMRI) for visual pathway imaging via topical administration requires further research. This study investigated the permeability of the corneal epithelium and corneal toxicity after topical administration of Mn2+ to understand the applicability of MEMRI.</p><p><b>METHODS</b>Forty New Zealand rabbits were divided into 0.05 mol/L, 0.10 mol/L, and 0.20 mol/L groups as well as a control group (n = 10 in each group). Each group was further subdivided into epithelium-removed and epithelium-intact subgroups (n = 5 in each subgroup). Rabbits were given 8 drops of MnCl2in 5 min intervals. The Mn2+ concentrations in the aqueous and vitreous humors were analyzed using inductively coupled plasma-mass spectrometry at different time points. MEMRI scanning was carried out to image the visual pathway after 24 h. The corneal toxicity of Mn2+ was evaluated with corneal imaging and pathology slices.</p><p><b>RESULTS</b>Between the aqueous and vitreous humors, there was a 10 h lag for the peak Mn2+ concentration times. The intraocular Mn2+ concentration increased with the concentration gradients of Mn2+ and was higher in the epithelium-removed subgroup than that in the epithelium-intact subgroup. The enhancement of the visual pathway was achieved in the 0.10 mol/L and 0.20 mol/L epithelium-removed subgroups. The corresponding peak concentrations of Mn2+ were 5087 ± 666 ng/ml, 22920 ± 1188 ng/ml in the aqueous humor and 884 ± 78 ng/ml, 2556 ± 492 ng/ml in the vitreous body, respectively. Corneal injury was evident in the epithelium-removed and 0.20 mol/L epithelium-intact subgroups.</p><p><b>CONCLUSIONS</b>The corneal epithelium is a barrier to Mn2+, and the iris and lens septum might be another intraocular barrier to the permeation of Mn2+. An elevated Mn2+ concentration contributes to the increased permeation of Mn2+, higher MEMRI signal, and corneal toxicity. The enhancement of the visual pathway requires an effective Mn2+ concentration in the vitreous body.</p>

Reduction of Interhemispheric Functional Connectivity in Sensorimotor and Visual Information Processing Pathways in Schizophrenia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Previous studies have demonstrated interhemispheric functional connectivity alterations in schizophrenia. However, the relationship between these alterations and the disease state of schizophrenia is largely unknown. Therefore, we aimed to investigate this relationship using voxel-mirrored homotopic connectivity (VMHC) method.</p><p><b>METHODS</b>This study enrolled 36 schizophrenia patients with complete remission, 58 schizophrenia patients with incomplete remission and 55 healthy controls. The VMHC was calculated based on resting-state functional magnetic resonance imaging data. Differences in VMHC among three groups were compared using one-way analysis of variance. A brain region with a significant difference in VMHC was defined as a region of interest (ROI), and the mean VMHC value in the ROI was extracted for the post hoc analysis, i.e., pair-wise comparisons across the three groups.</p><p><b>RESULTS</b>VMHC in the visual region (inferior occipital and fusiform gyri) and the sensorimotor region (paracentral lobule) showed significant differences among the three groups (P < 0.05, a false discovery rate method corrected). Pair-wise comparisons in the post hoc analysis showed that VMHC of the visual and sensorimotor regions in schizophrenia patients with complete remission and incomplete remission was lower than that in healthy controls (P < 0.05, Bonferroni corrected); however, there was no significant difference between the two patient subgroups.</p><p><b>CONCLUSIONS</b>Interhemispheric functional connectivity in the sensorimotor and visual processing pathways was reduced in patients with schizophrenia, but this reduction was unrelated to the disease state; thus, this reduction may serve as a trait marker of schizophrenia.</p>

Caracterización de una población con discapacidad visual (baja visión y ceguera) atendida en dos instituciones prestadoras de salud de Medellín / Characterization of a population with visual disabilities (low vision and blindness) attended in two health institutions from Medellín / Caracterização de uma população com incapacidade visual (baixa visão e cegueira) atendida em duas instituições prestadoras de saúde de Medellín

Objetivo: caracterizar, en los ámbitos clínico y sociodemográfico, una población de pacientes con discapacidad visual atendidos en dos instituciones de salud de la ciudad de Medellín (departamento de Antioquia/Colombia), con énfasis en la etiología del déficit visual irreversible. Metodología: estudio observacional descriptivo. Estudio macro sobre deficiencias visuales unilaterales y bilaterales en 1 742 registros de historias clínicas para identificar pacientes con baja visión o ceguera. Aplicación de un formato de investigación orientado a validar los pacientes con discapacidad visual y se seleccionaron 107 historias clínicas. Resultados: el 56.6% presenta discapacidad visual tipo baja visión y el 43.4% discapacidad visual tipo ceguera. El déficit visual responsable de la discapacidad visual fue del 39% por causas oftalmológicas, 20% por alteraciones neuro-oftalmológicas y 17% por trastornos neurológicos de cortezas visuales. Además de la agudeza visual, se encontraron otras deficiencias de la función visual: atrofia óptica, alteración electrofisiológica de la conducción visual y encefalomalacia en cortezas visuales. El 82% de los pacientes tiene al menos una comorbilidad no oftalmológica. Conclusiones: es fundamental un adecuado registro de las características biológicas, sociales, psicológicas y de las actividades de rehabilitación de los pacientes con baja visión y ceguera, para entender en forma integral no sólo la discapacidad sino el impacto que produce.

Objective: to characterize the clinical and socio-demographical characteristics of a population of patients with visual impairment attended at two health institutions in Medellín (Antioquia, Colombia), with an emphasis on the etiology of irreversible vision loss. Methodology: Observational, descriptive study of unilateral and bilateral visual impairment in 1 742 medical records to identify patients with low vision or blindness. A research form was used to validate patients with visual impairment, and 107 medical records were selected. Results: 56.6% presented low vision and 43.4% presented blindness. Vision loss was due to ophthalmic causes in 39% of cases, 20% were caused by neuro-ophthalmic alterations and 17% by neurological disorders of the visual cortex. In addition to visual acuity, other visual impairments were found, such as optic atrophy, electrophysiological alteration of the visual pathway, and encephalomalacia in visual cortices. 82% of patients had at least one nonophthalmic comorbidity. Conclusions: Adequate registration of rehabilitation activity, biological, social, and psychological characteristics of patients with low vision and blindness is essential in order to fully understand both the impairment and its impact.

Objetivo: caracterizar, nos âmbitos clínico e sócio-demográfico, uma população de pacientes com incapacidade visual atendidos em duas instituições de saúde da cidade de Medellín (departamento de Antioquia/Colômbia), com énfase na etiologia do déficit visual irreversível. Metodologia: estudo observacional descritivo. Estudo macro sobre deficiências visuais unilaterais e bilaterais em 1 742 registros de histórias clínicas para identificar pacientes com baixa visão ou cegueira. Aplicação de um formato de investigação orientado a validar os pacientes com incapacidade visual e se selecionaram 107 histórias clínicas. Resultados: 56.6% apresenta incapacidade visual tipo baixa visão e 43.4% incapacidade visual tipo cegueira. O déficit visual responsável da incapacidade visual foi de 39% por causas oftalmológicas, 20% por alterações neuro-oftalmológicas e 17% por transtornos neurológicos de córtex visual. Ademais da agudeza visual, se encontraram outras deficiências da função visual: atrofia óptica, alteração eletrofisiológica da condução visual e encefalomalácia em córtex visual. 82% dos pacientes têm pelo menos uma comorbilidade não oftalmológica. Conclusões: é fundamental um adequado registro das características biológicas, sociais, psicológicas e das atividades de reabilitação dos pacientes com baixa visão e cegueira, para entender em forma integral não só a incapacidade senão o impacto que produz.

Analysis of Visual Field Defect in Patient with Brain Lesion

PURPOSE: In this study we analyzed the results of visual field tests in patients diagnosed with a brain lesion in an ophthalmology clinic. METHODS: The medical records of 55 patients who underwent visual field examinations and diagnosed with brain pathology using magnetic resonance imaging (MRI) from January 1, 2005 to June 30, 2014 were retrospectively investigated. RESULTS: Of the 55 patients (M:F = 30:25), 31 displayed symmetrical hemianopsia, a typical visual field defect associated with brain lesions. Twenty-four patients showed atypical visual field defect (20 showed normal visual field despite the brain lesion, 3 had bilateral narrowing of the peripheral visual field in 2 cerebral infarctions and 1 multiple sclerosis, and 1 had horizontal inferior visual field defect in 1 eye from nasopharyngeal cancer). CONCLUSIONS: Patients having a brain lesion with the optic tract invasion may present with atypical visual field defects. The peripheral visual field constriction and horizontal inferior visual field defect in 1 eye could be the visual field defect in patients with a brain lesion.

Anatomic study of the optical radiation and its relationship in the temporal lobe: definition of a secure approach for amigdalohipocampectomy in epilepsy surgery / Estudio anatómico de la radiación óptica y su relación en el lóbulo temporal: definición de un abordaje seguro para amigdalohipocampectomía en cirugía de la epilepsia

Introducción/Objetivos: El lóbulo temporal anterior tiene importantes estructuras subcorticales, especialmente fibras blancas que llevan la información visual. La comprensión de esta región anatómica, importantes para la práctica microquirúrgica, se basa en técnicas de disección de fibras. Ellos proporcionan perspectiva tridimensional de esta región y añaden un enfoque quirúrgico exitoso para el tratamiento de las lesiones temporales mesiales. El propósito de este trabajo es el estudio de la anatomía de la pared lateral del ventrículo lateral con el fin de determinar una zona libre de la radiación óptica. Métodos: Se diseccionaron diez hemisferios cerebrales, preparados de acuerdo con técnicas de Klingler. Se utilizan espátulas de madera con puntas de diferentes tamaños. La radiación óptica fue delimitada y las medidas se tomaron a partir de esta estructura para el polo temporal, que se utiliza como punto de referencia. Resultados: Abordajes para el cuerno temporal superior a 27 mm más allá del polo temporal pueden cruzar asa de Meyer y determinar un perjuicio a la radiación óptica con los consiguientes déficits en los campos visuales. Conclusión: La determinación de la zona de libre de fibras de radiación óptica es factible. En este trabajo se podría inferir que el área libre de la radiación óptica se encuentra en la región anterioinferior del lóbulo temporal a una distancia de hasta 2,7 centímetros desde el polo temporal y permite el acceso a el hipocampo y la amígdala durante la cirugía de la epilepsia. Resecciones más grandes que estas medidas permiten aclarar de una lesión a la radiación óptica con los consiguientes déficits en los campos visuales.

Introduction/Objective: The anterior temporal lobe has important subcortical structures, especially white fibers that lead visual information. Understanding this anatomical region, important for microsurgical practice, is based on fibers dissection techniques. They provide three-dimensional perspective for this region and add a successful surgical approach for the treatment of mesial temporal lesions. The purpose of this paper is to study the anatomy of the lateral wall of the lateral ventricle in order to determine a free area of the optical radiation. Methods: Ten cerebral hemispheres were dissected, prepared according to Klingler´s techniques. Wooden spatulas with tips of various sizes were used. The optical radiation was delimited and measures were taken from this structure to the temporal pole, used as a reference point. Results: Approaches to the temporal horn larger than 27 mm beyond the temporal pole can cross Meyer´s loop and determine injury to the optical radiation with consequent postoperatively deficits in visual fields. Conclusion: The determination of free area of optical radiation fibers is feasible. In this work we could infer that free area of optical radiation is located in the anterioinferior region of the temporal lobe at a distance of up to 2.7 centimeters from the temporal pole and allows access to the hippocampus and amygdala during epilepsy surgery. Larger resections than these measures can possibly determine injury to the optical radiation with consequent deficits in visual fields.

Macroadenoma hipofisário: alterações campimétricas visuais / Pituitary macroadenoma: visual field defects

O macroadenoma de hipófise é um tumor de evolução lenta e que apresenta importantes distúrbios visuais como baixa acuidade visual e alterações campimétricas. Estes sintomas levam os pacientes a procurarem, muitas vezes, os oftalmologistas. Neste caso, analisaremos uma paciente portadora de glaucoma que apresentava, associadamente, um macroadenoma hipofisário.

The pituitary adenoma is a tumor of slow evolution and has important visual disturbances such as low visual acuity and field defects. These symptoms lead patients to seek often ophthalmologists. In this case, we will analyze a patient with glaucoma who had an associated pituitary macroadenoma.

Demonstration of Traumatic Subarachnoid Hemorrhage from the Anterior Choroidal Artery

We present a case of angiographically confirmed transection of the cisternal segment of the anterior choroidal artery (AChA) associated with a severe head trauma in a 15-year old boy. The initial brain computed tomography scan revealed a diffuse subarachnoid hemorrhage (SAH) and pneumocephalus with multiple skull fractures. Subsequent cerebral angiography clearly demonstrated a complete transection of the AChA at its origin with a massive extravasation of contrast medium as a jet trajectory creating a plume. We speculate that severe blunt traumatic force stretched and tore the left AChA between the internal carotid artery and the optic tract. In a simulation of the patient's brain using a fresh-frozen male cadaver, the AChA is shown to be vulnerable to stretching injury as the ipsilateral optic tract is retracted. We conclude that the arterial injury like an AChA rupture should be considered in the differential diagnosis of severe traumatic SAH.

Visual recovery demonstrated by functional MRI and diffusion tensor tractography in bilateral occipital lobe infarction / 영남의대학술지

We report on a patient who showed visual recovery following bilateral occipital lobe infarct, as evaluated by follow up functional magnetic resonance imaging (fMRI) and diffusion tensor tractography (DTT). A 56-year-old female patient exhibited severe visual impairment since onset of the cerebral infarct in the bilateral occipital lobes. The patient complained that she could not see anything, although the central part of the visual field remained dimly at 1 week after onset. However, her visual function has shown improvement with time. As a result, at 5 weeks after onset, she notified that her visual field and visual acuity had improved. fMRI and DTT were acquired at 1 week and 4 weeks after onset, using a 1.5-T Philips Gyroscan Intera. The fiber number of left optic radiation (OR) increased from 257 (1-week) to 353 (4-week), although the fiber numbers for right OR were similar. No activation in the occipital lobe was observed on 1-week fMRI. By contrast, activation of the visual cortex, including the bilateral primary visual cortex, was observed on 4-week fMRI. We demonstrated visual recovery in this patient in terms of the changes observed on DTT and fMRI. It appears that the recovery of the left OR was attributed more to resolution of local factors, such as peri-infarct edema, than brain plasticity.

Visual pathway abnormalities were found in most multiple sclerosis patients despite history of previous optic neuritis / Anormalidades nas vias visuais foram encontradas na maior parte dos pacientes com esclerose multipla independentemente da historia de neurite optica

Objective It was to investigate visual field (VF) abnormalities in a group of multiple sclerosis (MS) patients in the remission phase and the presence of magnetic resonance imaging (MRI) lesions in the optic radiations. Methods VF was assessed in 60 participants (age range 20-51 years): 35 relapsing-remitting MS patients [20 optic neuritis (+), 15 optic neuritis (-)] and 25 controls. MRI (3-Tesla) was obtained in all patients. Results Visual parameters were abnormal in MS patients as compared to controls. The majority of VF defects were diffuse. All patients except one had posterior visual pathways lesions. No significant difference in lesion number, length and distribution was noted between patients with and without history of optic neuritis. One patient presented homonymous hemianopsia. Conclusion Posterior visual pathway abnormalities were found in most MS patients despite history of previous optic neuritis. .

Objetivo Foi analisar o campo visual (CV) de um grupo de pacientes com esclerose múltipla (EM) na fase remissiva e a presença de lesões nas imagens de ressonância magnética (MRI) na radiação óptica. Método O CV foi estudado em 60 participantes (faixa etária de 20-51 anos): 35 pacientes EM remitente-recorrente: [20 neurite óptica (+), 15 neurite óptica (-)] e 25 controles. Foram obtidas MRI (3-Tesla) de todos os pacientes. Resultados Havia alterações visuais nos pacientes com EM quando comparados aos controles. A maioria apresentava defeitos difusos de CV. Todos os pacientes, à exceção de um, apresentaram lesões nas vias visuais posteriores. Não foi observada diferença significativa quanto a número, extensão e distribuição das lesões entre os pacientes com e sem história de neurite óptica. Um paciente apresentou hemianopsia homônima. Conclusão Anormalidades nas via visuais posteriores foram encontradas na maior parte dos pacientes com EM independentemente da história de neurite óptica. .