Objective Assessment of Visual Field Defects Caused by Optic Chiasm and Its Posterior Visual Pathway Injury.

OBJECTIVES: To investigate the characteristics and objective assessment method of visual field defects caused by optic chiasm and its posterior visual pathway injury. METHODS: Typical cases of visual field defects caused by injuries to the optic chiasm, optic tracts, optic radiations, and visual cortex were selected. Visual field examinations, visual evoked potential (VEP) and multifocal visual evolved potential (mfVEP) measurements, craniocerebral CT/MRI, and retinal optical coherence tomography (OCT) were performed, respectively, and the aforementioned visual electrophysiological and neuroimaging indicators were analyzed comprehensively. RESULTS: The electrophysiological manifestations of visual field defects caused by optic chiasm injuries were bitemporal hemianopsia mfVEP abnormalities. The visual field defects caused by optic tract, optic radiation, and visual cortex injuries were all manifested homonymous hemianopsia mfVEP abnormalities contralateral to the lesion. Mild relative afferent pupil disorder (RAPD) and characteristic optic nerve atrophy were observed in hemianopsia patients with optic tract injuries, but not in patients with optic radiation or visual cortex injuries. Neuroimaging could provide morphological evidence of damages to the optic chiasm and its posterior visual pathway. CONCLUSIONS: Visual field defects caused by optic chiasm, optic tract, optic radiation, and visual cortex injuries have their respective characteristics. The combined application of mfVEP and static visual field measurements, in combination with neuroimaging, can maximize the assessment of the location and degree of visual pathway damage, providing an effective scheme for the identification of such injuries.

Relationship Between Contact Lens Sensor Output Parameters and Visual Field Progression in Open-angle Glaucoma: Assessment of a Practical Tool to Guide Clinical Risk-assessment.

PURPOSE: In recent years, new technologies have emerged to better analyze and interpret intraocular pressure (IOP) fluctuations. Among them is the progression report (PR), an algorithm based on continuous contact lens sensor (CLS) readings to estimate the likelihood of fast visual field (VF) glaucomatous progression. The objective of this study is to validate the PR. METHODS: In this retrospective study, 30 open-angle glaucoma patients were enrolled. Twenty-four hours IOP-related variations were recorded using a CLS. Recordings were used to generate PR. The likelihood of fast VF progression (<-1 dB/y mean deviation) was estimated by 2 masked assessors based on clinical parameters. At least 3 VF were performed over the 2 years following the initial assessment, to determine actual progression. RESULTS: Mean age was 65.9±10.45 years, with a mean baseline mean deviation of -5.4±5.1. After a mean follow-up of 29.5±12.9 months, 26.7% of eyes were assessed as fast progressors (-2.9±1.9 dBs/y). The average risk-score attributed by the PR was 42% [41% (slow) vs. 44% (fast); P=0.035]. Correlations between the 2 assessors were good (r=0.59), and identical to that between PR and the averaged assessors' gradings. Correlations between mean deviation progression rates and PR, Assessor 1 and Assessor 2's gradings were, r=0.57, 0.31, and 0.43, respectively. CONCLUSIONS: PR provided comparable predictions of the risk of fast VF progression as did physician estimates based on all available clinical data. With their relationship to the eye's biomechanical properties and the ocular tissues' response to pressure variations, CLS recordings may offer new information that complements conventional examinations.

MANAGEMENT OF ENDOCRINE DISEASE: Visual morbidity in patients with pituitary adenoma.

Visual dysfunction is an important element in the morbidity encountered in patients with pituitary adenoma leading to functional impairment and compromised quality of life. It consists of many parameters (even in the absence of reported symptomatology) as a result of tumour growth in proximity to structures critical for vision (anterior visual pathway, cranial nerves within cavernous sinuses), and as an adverse consequence of therapeutic interventions. Adenoma resection leads to high rates of visual improvement and possibly continues beyond a year post surgery, but the exact timing of maximum effect requires elucidation. Retinal nerve fibre layer measurement may be a reliable, objective parameter predicting favourable visual outcomes, although its prognostic value when pathological, needs to be confirmed. For compromised vision after pituitary apoplexy, early surgical decompression remains usual practice until evidence-based guidance becomes available. The risk of radiation-induced visual toxicity is mainly influenced by total and per fraction dose of radiation and treatment modality. Careful selection of cases and of radiotherapy technique/planning are of major importance in minimising this risk. Dopamine agonists lead to visual recovery in a considerable number of prolactinoma patients. Visual morbidity should be considered a vital indicator in the metrics of quality of service/care in pituitary disease making regular, full ophthalmic examination an essential component of modern management of pituitary pathology at all time points of patient pathway. Well-designed studies minimising effects of bias and using tools and scoring systems reliably reflecting visual status will provide robust evidence on valid prognostication and patient stratification guiding clinical decision making.

Assessment of the deformation of the outer nuclear layer in the Epiretinal membrane using spectral-domain optical coherence tomography.

BACKGROUND: We aimed to investigate the deformation of the outer nuclear layer using optical coherence tomography in patients with epiretinal membrane (ERM) and its relationship with metamorphopsia. METHODS: Thirty-nine eyes from 39 patients with ERM were included in the study. Patients with the subtypes of pseudo macula hole and lamellar hole were excluded. Twenty-one fellow eyes without macular disease were included as normal controls. Forty-nine B-scan images were obtained in the range of 20 degrees around the macula using SD-OCT. The outer nuclear layer (ONL) was evaluated as a three-dimensional image (3D-ONL) reconstructed using the distance between the ONL and retinal pigment epithelium (RPE) line. The deformation of the ONL was figured at the reference plane and evaluation plane (ONL-B). The characteristic parameters of the ONL-B were defined as circularity, area ratio, and axis ratio. The correlations between these parameters and visual acuity and MCHART score ratio (MH/MV) were then evaluated. RESULTS: ONL height was significantly higher in ERM patients than in normal controls (54.1 ± 5.3 µm and 84.1 ± 12.9 µm, respectively; P < 0.001). In ERM patients, the MV score was 0.53 ± 0.50, the MH score was 0.71 ± 0.61, and the distance from the RPE line to the ONL-B was 153.5 ± 13.5 µm. The axis of the ONL-B in normal controls and ERM patients was - 6.25 ± 21.8 and - 1.28 ± 29.1, respectively, which indicates that the ONL is horizontally long in both normal individuals and ERM patients. The circularity and area ratio were significantly smaller in ERM patients than in normal controls. In all ERM patients, MH/MV had a significant correlation with axis (r = - 0.29, p = 0.034), circularity (r = - 0.28, p = 0.044), and area ratio (r = - 0.47, p = 0.001). Moreover, we found that the correlation was more significant if the subjects had an axis of the ONL within ±10 degrees (n = 16); the correlations of MH/MV with axis (r = - 0.29, p = 0.034), circularity (r = - 0.53, p = 0.021), and area ratio were more significant (r = - 0.78, P < 0.0001). CONCLUSION: The ONL is horizontally long in normal individuals and ERM patients. The direction of metamorphopsia is correlated with the direction of ONL deformation.

Chronic health conditions and school performance in first graders: A prospective cohort study.

OBJECTIVE: Children with chronic health conditions may perform poorer at school. Associations may be confounded by numerous social factors. We aimed to estimate the effects of a chronic health condition on overall school performance in first graders with an emphasis on rigorous adjustment for potential confounders. METHODS: A population-based cohort study was performed in the area of Mainz-Bingen (Germany). In 2015 all preschoolers were approached and the presence of a chronic health condition was assessed by parental questionnaires and preschool health examination data. The identification of a chronic health condition was based on special health care needs and presence of a doctor's diagnosis out of 24 school-relevant diseases. At the end of the first school year, overall school performance was assessed by teachers and rated on a 5-item scale ranging from -10 to +10. RESULTS: Of 3683 children approached, 2003 were enrolled. Overall school performance was available for 1462 children (51% boys). Of these, 52% suffered from a chronic health condition. Compared to children without a chronic health condition, children with special health care needs (15%) performed worse at school (adjusted mean difference: -0.95, 95% CI: [-1.55; -0.35], P = 0.002). Children with a doctor's diagnosis but without special health care needs (37%) did not perform worse at school. The effect was further analysed considering the extent of special health care needed. CONCLUSIONS: Chronic health conditions affect overall school performance early in primary school. To identify academically at-risk children, a chronic health condition identification based on special health care needs may be used.

The diagnosis and assessment of visual function in Singaporean children with electrophysiology: 10-year results.

PURPOSE: To study the clinical use and efficacy of electrophysiology in children. METHODS: This was a retrospective review of all children aged <16 years, who were referred to the Visual Electrophysiology Laboratory at the Singapore National Eye Center between 2003 and 2013. RESULTS: A total of 586 children, median age 8 years (range 0.15-16), were referred for a variety of reasons including investigation of poor vision (40 %), suspected retinal disease or optic nerve/cortical dysfunction (17 %), nystagmus (13 %) and screening or monitoring of a variety of ocular or neurological conditions (12 %). The number of children with vision 6/15 or worse was 418 (71 %), and 103 (18 %) had vision 6/120 or worse in at least one eye. The most common pathology noted was retinal dystrophy or dysfunction (41 %) or optic nerve/cortical dysfunction (12 %). In 30 %, visual electrophysiology was within normal limits, and in 6 %, a conclusive diagnosis could not be obtained. CONCLUSION: Electrophysiology testing played an important role in the assessment of children and added to the clinical management of the patient.

Modeling of vision loss due to vitreous hemorrhage by Monte Carlo simulation.

Vitreous hemorrhage is the leaking of blood into the vitreous humor which results from different diseases. Vitreous hemorrhage leads to vision problems ranging from mild to severe cases in which blindness occurs. Since erythrocytes are the major scatterers in blood, we are modeling light propagation in vitreous humor with erythrocytes randomly distributed in it. We consider the total medium (vitreous humor plus erythrocytes) as a turbid medium and apply Monte Carlo simulation. Then, we calculate the parameters characterizing vision loss due to vitreous hemorrhage. This work shows that the increase of the volume fraction of erythrocytes results in a decrease of the total transmittance of the vitreous body and an increase in the radius of maximum transmittance, the width of the circular strip of bright area, and the radius of the shadow area.

Autism assessment in children with optic nerve hypoplasia and other vision impairments.

AIM: This study examined the utility of standard autism diagnostic measures in nine children (aged 5-9y) with severe vision impairment and a range of social and language functioning. METHOD: The Autism Diagnostic Observation Schedule (ADOS) and the Autism Diagnostic Interview, Revised (ADI-R) were systematically modified and used to assess symptoms of autism in children with vision less than or equal to 20/800, the majority of whom had optic nerve hypoplasia. The results of the assessments, including analysis of symptom patterns, were compared with expert autism diagnoses. RESULTS: Modified autism measures demonstrated good agreement with clinical diagnoses. Symptoms found to be most and least reliable in discriminating autism from behaviors common to most children with congenital vision impairment are described. Comparisons of current behavior with parent-reported behaviors from a younger age suggested that some symptoms of autism in very young children who are congenitally blind may improve with age. INTERPRETATION: The ADOS and ADI-R are useful for clinical assessment and for advancing research efforts to understand autism symptoms in children with vision impairment. However, some autistic symptoms in very young children may change over time, and developmental changes should be closely monitored.

Assessment of metamorphopsia in patients with central serous chorioretinopathy.

BACKGROUND: To evaluate the presence and extent of metamorphopsia using M-CHARTS TM (Inami Co., Tokyo, Japan) in patients with central serous chorioretinopathy (CSC). DESIGN: Retrospective consecutive medical record review in a university hospital. MATERIALS AND METHODS: We examined 33 eyes of 33 consecutive CSC patients using M-CHARTS, which yields scores reflecting the severity of metamorphopsia. The condition was considered present when an M-CHARTS score was 0.3 or over. In all patients, optical coherence tomography (OCT) was performed, best-corrected visual acuity (BCVA) was assessed, and M-CHARTS scores were calculated at the first and the 1- and 3-month follow-up visits. The correlation between M-CHARTS scores and BCVA values was determined. We also sought to define relationships between the level of metamorphopsia and specific OCT findings. RESULTS: Of 33 CSC patients, 15 showed symptoms of metamorphopsia, and all 15 had M-CHARTS scores of over 0.3. However, no correlation was evident between BCVA values and the extent of metamorphopsia as determined using M-CHARTS. In metamorphopsia patients, the incidence of focal retinal pigment epithelial detachment was notably greater than in the non-metamorphopsia group (P = 0.03). CONCLUSION: M-CHARTS is valuable for monitoring subjective symptom improvement during the clinical course of CSC. M-CHARTS serves as a useful adjunct to OCT.

Alzheimer's disease in the retina: imaging retinal aß plaques for early diagnosis and therapy assessment.

BACKGROUND: Definite Alzheimer's disease (AD) diagnosis at early stages is vital for targeting intervention, yet currently unavailable. Noninvasive detection of the pathological hallmark, amyloid-ß protein (Aß) plaques, is limited in the brain. However, the existence of Aß plaques in the retina, possibly at presymptomatic stages, may improve early detection of AD. OBJECTIVE: To summarize clinical and preclinical evidence showing that the retina, an accessible part of the central nervous system, displays abnormalities in AD, especially Aß plaque pathology. The ability to monitor in vivo retinal plaque dynamics in response to immunotherapy is also assessed. METHODS: Literature analysis of retinal AD pathology and imaging is provided. In our studies, systemic curcumin is administered to enable monitoring of retinal Aß plaques in live APP(SWE)/PS1(Δ)(E9) transgenic mice by optical imaging. RESULTS: Visual and retinal abnormalities, including early manifestation of retinal Aß plaque pathology, have been documented in AD patients and animal models. In mouse models, retinal Aß plaques accumulate with age and decrease in response to immunotherapy, consistent with brain pathology. Here, we demonstrate that retinal plaques can be individually monitored in real time following glatiramer acetate immunization. CONCLUSION: Translation of noninvasive retinal-plaque imaging to humans could eventually facilitate early and accurate AD diagnosis and therapy assessment.

Late ophthalmological assessment of patients with subarachnoid hemorrhage and clipping of cerebral aneurysm.

PURPOSE: To estimate prospectively late ocular manifestations in patients after aneurysmal subarachnoid hemorrhage (SAH) treated with aneurysm clipping. METHODS: Forty-six patients (12 men and 34 women), 23-69 years of age, were included in this study. A conventional ophthalmological examination, visual evoked potentials (VEPs), and static perimetry were performed on all patients. The mean interval between the onset of SAH and the aforementioned examination was 1.9 ± 1.3 years (range 0.5-5 years). The following were compared between patients with affected and non-affected visual fields as well as between those with normal and abnormal VEPs: sex, age, time from SAH to surgery, Hunt and Hess scale, Glasgow Coma Scale, Glasgow Outcome Scale, grading of SAH according to the Fisher scale, and the size and site of aneurysm. RESULTS: Visual field defects were found in 23 patients (50%). In all of these patients, both eyes were affected. The most frequent type of visual field defects were: constricted field (47.8%), multiple peripheral foci (26.1%), and superior field defect (17.4%). There was no significant relationship between the analyzed factors and the occurrence of visual field defects, although statistical significance was almost observed in respect to the Fisher scale (p = 0.055). Deterioration in VEPs was observed in nine patients (19.6%). In the group of patients with abnormal VEPs, the time from onset of SAH to surgery was 2.6 ± 1.8 days, whereas in the group of patients with normal VEPs this time amounted to 6.4 ± 2.4 days (p = 0.02). In patients with no changes in VEPs, the mean Fisher score was significantly higher than in the group with abnormal VEPs (2.8 ± 0.6 vs 2.0 ± 0.4 respectively, p = 0.04). CONCLUSION: Visual field defects and VEP deterioration are frequent late ocular manifestations of SAH treated with aneurysm clipping. Damage to the visual pathway correlates with the severity of SAH and timing of aneurysmal surgery.

Rehabilitative intervention and social participation of a case with Balint's syndrome and aphasia.

Balint's syndrome is characterized by three major disorders of spatial analysis: fixed gaze or psychic paralysis, simultagnosia, and optic ataxia or misreaching. Most patients with Balint's syndrome generally do not show all three of these signs. The authors herein reported the more than four-year clinical course of a case (a 43-year-old man) with Balint's syndrome presenting these three disorders. The patient also had a mild type of conduction aphasia, but his attentional, intellectual and memory functions were well preserved. SPECT showed cerebral hypoperfusion in the bilateral parieto-occipital areas. Whereas rehabilitative intervention with process specific approach for the impaired visual cognition seemed to be significantly ineffective, a functional adaptation approach successfully promoted the patient's social participation. However, the present patient could not help having to resign from his job. Additionally, double impairment of visual (including optic ataxia) and language functions made it impossible for him to obtain a new work. Like the present case, those who have a higher brain dysfunction, but retain good physical ability can hardly receive the benefit of the social welfare system in Japan. Legislation addressing this problem is a matter of great urgency.

Progression of visual loss and time between initial assessment and treatment of wet age-related macular degeneration.

PURPOSE: To determine whether the time elapsed from initial (referral) diagnosis of neovascular (wet) age-related macular degeneration (AMD) to assessment and treatment by a retinal specialist is associated with visual deterioration in the intervening period. METHODS: A prospective pilot study of 38 consecutive AMD patients who presented with newly diagnosed subfoveal choroidal neovascularization was conducted in a tertiary care retinal practice. All eligible subjects underwent clinical examination and digital fluorescein angiography at the time of assessment by a retinal specialist. Correlations were performed to assess the association between continuous independent variables and any visual deterioration since initial diagnosis. Multivariate linear regression models with stepwise techniques were used to evaluate any association between visual progression and time elapsed, while controlling for potential clinical covariates. RESULTS: Of the 38 patients, 32 (84%) met the inclusion and exclusion criteria; no differences in important variables were noted between those included and those excluded. The median time between initial diagnosis and referral assessment and treatment was 28 days (interquartile range=36.5 days); some degree of visual loss developed in 14 (44%) of the subjects. The elapsed time was correlated with progression of visual loss (r=0.50, p=0.003). Multivariate linear regression demonstrated that only time elapsed and lesion type based on fluorescein angiography were associated with progression of visual loss (R2=0.491, F(4,28)=6.744, p=0.001); lesion size, age and sex were not significantly associated with progression of visual loss. INTERPRETATION: Delay in assessment and treatment of new-onset wet AMD by a retinal specialist is associated with a higher risk of visual loss.

Clinical assessment of complex visual dysfunction.

The study of patients with lesions of the central visual system has shown that certain complex visual disturbances are generally associated with lesions in the ventral occipital lobe and adjoining temporal lobe, while other disturbances are more commonly associated with lesions of the dorsal occipital cortices and adjoining parietal lobe. Cerebrovascular lesions in the distribution of the posterior cerebral artery, tumor, trauma, and neurodegenerative processes such as Alzheimer's disease are common etiologies of these disturbances and can be assessed using modern neuroimaging techniques. The corresponding visual function deficits can be separated out by a systematic clinical approach incorporating visual sensory and cognitive testing procedures, as outlined below.

Histopathological and laboratory assessment of visual dysfunction.

The currently available methods of assessing ocular toxicity are discussed. Manifestations of ocular toxicity are best described clinically; histopathological examination of the eye is beset with problems of preparing the eye for morphological examinations. Electron microscopy is essential to look for chemically induced side effects at the cellular level. Mechanisms of ocular toxicity are poorly understood, and the limitation of animal studies in predicting side effects in man must be appreciated.