Abnormal Visual Function Research Articles

Chapter 19 - Rehabilitation of visual disorders

While there is a long history of rehabilitation for motor deficits following cerebral lesions, less is known about our ability to improve visual deficits. Vision therapy, prisms, occluders, and filters have been advocated for patients with mild traumatic brain injury, on the premise that some of their symptoms may reflect abnormal visual or ocular motor function, but the evidence for their efficacy is modest. For hemianopia, attempts to restore vision have had unimpressive results, though it appears possible to generate blindsight through training. Strategic approaches that train more efficient use of visual search in hemianopia have shown consistent benefit in visual function, while prism aids may help some patients. There are many varieties of alexia. Strategic adaptation of saccades can improve hemianopic alexia, but there has been less work and mixed results for pure alexia, neglect dyslexia, attentional dyslexia, and the central dyslexias. A number of approaches have been tried in prosopagnosia, with recent studies of small groups suggesting that face perception of prosopagnosic subjects can be enhanced through perceptual learning.

Congenital Zika syndrome: A systematic review.

The signs and symptoms of Zika virus infection are usually mild and self-limited. However, the disease has been linked to neurological complications such as Guillain-Barré syndrome and peripheral nerve involvement, and also to abortion and fetal deaths due to vertical transmission, resulting in various congenital malformations in newborns, including microcephaly. This review aimed to describe the o signs and symptoms that characterize the congenital Zika syndrome. A systematic review was performed with a protocol and described according to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The search strategy yielded 2,048 studies. After the exclusion of duplicates and application of inclusion criteria, 46 studies were included. The main signs and symptoms associated with the congenital Zika syndrome were microcephaly, parenchymal or cerebellar calcifications, ventriculomegaly, central nervous system hypoplasia or atrophy, arthrogryposis, ocular findings in the posterior and anterior segments, abnormal visual function and low birthweight for gestational age. Zika virus infection during pregnancy can cause a series of changes in the growth and development of children, while impacting the healthcare system due to the severity of cases. Our findings outline the disease profile in newborns and infants and may contribute to the development and updating of more specific clinical protocols.

Efavirenz-Associated Retinal Toxicity Presenting with Night Vision Defects in Patients with Human Immunodeficiency Virus

ABSTRACT Ocular lesions in patients with human immunodeficiency virus (HIV) are commonly due to underlying opportunistic infections. With highly active antiretroviral therapy (HAART), infectious lesions have reduced and noninfectious ocular manifestations including drug-related side effects have been noted. While retinal toxicity has been noted with few other HAART drugs, there are not many on the same with Efavirenz usage. We report a series of five patients with possible efavirenz-related retinal toxicity, visual function abnormalities, and its management. Efavirenz was replaced with alternate anti-retroviral drug. Reversal of ocular side effects were noted subjectively in the form of symptom amelioration of the patients. Objectively, it could be documented with electroretinogram changes and other visual function tests reverting back to normal after change in HAART regime. Early identification of this uncommon side effect in select patients can prevent irreversible vision loss due to efavirenz-associated retinal toxicity.

Early visual and neuro-development in preterm infants with and without retinopathy

BackgroundRetinopathy of prematurity (ROP) is often associated with visual impairment and multiple developmental disabilities. AimsAs most of the previous studies include infants with brain lesions, that can determine visual impairment per se, a cohort of low neurological risk preterm infants without ROP and with various degree of severity of ROP was assessed in order to establish visual and neurodevelopmental outcome. Study designPreterm infants born at <31 weeks gestation, without major brain lesions, underwent visual function assessment at 1 year corrected age and neurodevelopmental assessment at 2 years corrected age. SubjectsOne hundred and five infants were included in the study: 42 infants did not develop ROP, 7 reached stage 1 in zone 2 ROP, 37 reached prethreshold (untreated) type 2 ROP. The remaining 19 infants were classified as type 1 ROP. Outcome measuresVisual function (including fixing, tracking, visual acuity, visual field, attention at distance and nystagmus) were assessed at 12 months corrected age and Griffiths Scales at 2 years corrected age. ResultsThe severity of ROP was strongly correlated (p < 0.001) with both visual function at 1 year and neurodevelopment at 2 years. Similarly, the presence of nystagmus was also strongly correlated with visual and neurodevelopmental sequelae. ConclusionsInfants with no or milder retinopathy showed normal visual function at 1 year and neurodevelopment at 2 years. Infants who underwent treatment more frequently showed abnormal results on several aspects of visual function. Presence of nystagmus appeared to increase the risk for abnormal visual function and neurodevelopmental outcome.

Visual Function Tests as cost Effective Screening Tools For Diabetic Retinopathy

Purpose: To find out the importance of visual function tests as cost effective screening tools for diabetic retinopathy.&#x0D; Study Design: Descriptive, Cross sectional study.&#x0D; Place and Duration of Study: Ophthalmology Unit of Holy Family Hospital, from September 2018 to November 2018.&#x0D; Material and Methods: Two hundred and forty-two patients were selected by convenience sampling technique and were divided into three groups. Two groups of diabetics with and without retinopathy and one group of non-diabetics age-matched controls. After relevant history, patients were examined for Visual acuity, Color vision and Contrast sensitivity using Snellen’s Chart, 24 Plates Ishihara Chart and Pelli Robson Chart respectively. Staging of retinopathy was done after mydriasis.&#x0D; Results: Diabetic patients irrespective of type and stage, when compared with non-diabetic patients had a greater percentage of abnormal visual function tests. A 6/6 visual acuity was observed in 38.2% of non diabetics as compared to only 8.6% diabetics without retinopathy and 7.5% of diabetics with retinopathy. Color vision abnormalities were detected in only 8.6% of non diabetic patients. However, 11.1% of diabetics without retinopathy and 23.7% with retinopathy showed abnormalities of color vision. The percentage of abnormal Contrast sensitivity was 76.2% for diabetics with retinopathy and 60.4% for diabetics without retinopathy and 27.1% for non-diabetic patients.&#x0D; Conclusion: Evaluation of Visual Acuity, Color Vision and Contrast Sensitivity are cheap and easy tests that can be used to screen for diabetic retinopathy thereby allowing early interventions to prevent development of serious ocular diabetic complications.

Correlation of Visual Quality of Life With Clinical and Visual Status in Friedreich Ataxia.

The primary objective was to determine the association of patient-reported vision-specific quality of life to disease status and visual function in patients with Friedreich's ataxia (FRDA). Patients with FRDA were assessed with the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) along with measures of disease status (ataxia stage) and visual function (low- and high-contrast letter acuity scores). The relations of NEI-VFQ-25 scores to those for disease status and visual function were examined. Scores for the NEI-VFQ-25 were lower in patients with FRDA (n = 99) compared with published disease-free controls, particularly reduced in a subgroup of FRDA patients with features of early onset, older age, and abnormal visual function. The NEI-VFQ-25 captures the subjective component of visual function in patients with FRDA.

읽기 매체에 따른 시기능 정상안 및 이상안의 양안시기능 변화

읽기 매체에 따른 시기능 정상안 및 이상안의 양안시기능 변화

Identifying nonlinear dynamics of brain functional networks of patients with schizophrenia by sample entropy

Different regions in the human brain functionally connect with each other forming a brain functional network, and the time evolution of functional connectivity between different brain regions exhibits complex nonlinear dynamics. This study intends to characterize the nonlinear properties of dynamic functional connectivity and to explore how schizophrenia influences such nonlinear properties. The dynamic functional connectivity is constructed by analyzing resting-state functional magnetic resonance imaging data, and its nonlinear properties are characterized by sample entropy (SampEn), with larger SampEn values corresponding to more complexity. To identify the influence of schizophrenia on SampEn, the difference in SampEn between patients with schizophrenia and healthy controls is analyzed at different levels of the brain. It is shown that the patients exhibit significantly higher SampEn at different levels of the brain, and such phenomenon is mainly caused by a significantly higher SampEn in the visual cortex of the patients. Furthermore, it is also shown that SampEn of the visual cortex is significantly and positively correlated with the illness duration or the symptom severity scores. Because the visual cortex is implicated in the visual information processing, these results can shed light on abnormal visual functions of patients with schizophrenia, and also are consistent with the notion that the nonlinearity underlies the irregularity in psychotic symptoms of schizophrenia. This study extends the application of nonlinear dynamics in brain sciences and suggests that nonlinear properties are effective biomarkers in characterizing the brain functional networks of patients with brain diseases.

Clinical and genetic determinants of chronic visual pathway changes after methanol - induced optic neuropathy: four-year follow-up study

Context: Methanol poisoning induces acute optic neuropathy with possible long-term visual damage.Objective: To study the dynamics and key determinants of visual pathway functional changes during 4 years after acute methanol poisoning.Methods: A total of 42 patients with confirmed methanol poisoning (mean age 45.7 ± 4.4 years) were examined 4.9 ± 0.6, 25.0 ± 0.6, and 49.9 ± 0.5 months after discharge. The following tests were performed: visual evoked potential (VEP), retinal nerve fiber layer (RNFL) measurement, brain magnetic resonance imaging (MRI), complete ocular examination, biochemical tests, and apolipoprotein E (ApoE) genotyping.Results: Abnormal VEP P1 latency was registered in 18/42 right eyes (OD) and 21/42 left eyes (OS), abnormal N1P1 amplitude in 10/42 OD and OS. Mean P1 latency shortening during the follow-up was 15.0 ± 2.0 ms for 36/42 (86%) OD and 14.9 ± 2.4 ms for 35/42 (83%) OS, with maximum shortening up to 35.0 ms. No significant change of mean N1P1 amplitude was registered during follow-up.A further decrease in N1P1 amplitude ≥1.0 mcV in at least one eye was observed in 17 of 36 patients (47%) with measurable amplitude (mean decrease −1.11 ± 0.83 (OD)/−2.37 ± 0.66 (OS) mcV versus −0.06 ± 0.56 (OD)/−0.83 ± 0.64 (OS) mcV in the study population; both p < .001).ApoE4 allele carriers had lower global and temporal RNFL thickness and longer initial P1 latency compared to the non-carriers (all p < .05). The odds ratio for abnormal visual function was 8.92 (3.00–36.50; 95%CI) for ApoE4 allele carriers (p < .001). The presence of ApoE4 allele was further associated with brain necrotic lesions (r = 0.384; p = .013) and brain hemorrhages (r = 0.395; p = .011).Conclusions: Improvement of optic nerve conductivity occurred in more than 80% of patients, but evoked potential amplitude tended to decrease during the 4 years of observation. ApoE4 allele carriers demonstrated lower RNFL thickness, longer P1 latency, and more frequent methanol-induced brain damage compared to non-carriers.

Visual function in infants with antenatal Zika virus exposure

To report the findings of a cross-sectional study of visual function in infants with confirmed or suspected antenatal Zika virus (ZIKV) infection seen at a single referral center in Rio de Janeiro. Infants were examined following the ZIKV outbreak period at Instituto Fernandes Figueira/FIOCRUZ. Visual function was considered abnormal if an infant could not fix and follow a standardized high-contrast target (10cm) by 3-6months of age. Visual function and associations with structural eye abnormalities, central nervous system (CNS) abnormalities, microcephaly, and nystagmus were assessed. Sensitivity and specificity of screening criteria for structural eye abnormalities was assessed. A total of 173 infants met inclusion criteria. Abnormal visual function was found in 52 infants (30.0%) and was significantly associated with eye abnormalities (40/52; OR=44.2; 95% CI, 16.6-117.6), CNS abnormalities (50/52; OR=64.0; 95% CI, 14.7-277.6), microcephaly (44/52; OR=31.5; 95% CI, 12.7-77.8), and nystagmus (26/52; OR=120.0; 95% CI, 15.6-924.5). Using microcephaly as screening criteria for the detection of eye abnormalities provided a sensitivity of 88.9% (95% CI, 76.0-96.3) and specificity of 82.8% (95% CI, 75.1-88.9). Using both abnormal visual function and microcephaly increased sensitivity to 100% (95% CI, 92.1-100.0) and decreased specificity to 80.5% (95% CI, 72.5-86.9). Infants with suspected antenatal ZIKV infection and reduced visual function should be referred to an ophthalmologist. Visual function assessments are helpful in screening for antenatal ZIKV exposure in resource-limited settings and can identify infants who may benefit from visual habilitation.

Applications of Isolated-Check Visual Evoked Potential in Early Stage of Open-Angle Glaucoma Patients.

Background:Standard automated perimetry does not sufficiently detect early open-angle glaucoma (OAG) in the clinic. New visual function tests for early glaucoma damage are therefore needed. The present study evaluated whether an isolated-check visual evoked potential (icVEP) could be used to detect visual function abnormalities in early-stage OAG and to explore potential related factors.Methods:This was a cross-sectional study. Thirty-seven OAG patients with early-stage visual field loss (mean deviation ≥ −6.00 dB) detected by the Humphrey Field Analyzer (30-2 SITA program) and 26 controls were included in this study. Optical coherence tomography (OCT) was used to detect retinal nerve fiber layer (RNFL) defects. The icVEP preferentially evaluates the magnocellular-ON pathway. VEPs were recorded and signal-to-noise ratios (SNRs) were derived based on multivariate analysis. Eyes that yielded an SNR ≤1 were considered abnormal. Receiver operating characteristic (ROC) curve analysis was used to estimate the accuracy of group classification. Correlations between SNRs and related factors were analyzed.Results:Based on an SNR criterion of 1, the icVEP had a sensitivity of 62.2% and a specificity of 92.3% for diagnosing early-stage OAG with 74.6% classification accuracy. The ROC curve analysis, however, suggested that an SNR criterion of 0.93 would produce the highest classification accuracy (77.3%). Both RNFL thinning in the temporal superior quadrant on OCT and number of abnormal test points in the central 11° visual field (pattern deviation, P < 0.5%) significantly correlated with the SNR (P < 0.05).Conclusions:The icVEP detected visual function abnormalities in approximately 3/5 of eyes with early-stage OAG with greater than 90% specificity. SNR correlated with both a decrease in RNFL thickness and severity of central visual field loss.

A study of clinical and genetic characteristics of a Leber hereditary optic neuropathy family with the heteroplasmic m.14484T>C mutation

Objective: To study clinical and genetic characteristics of a Leber hereditary optic neuropathy (LHON) family with the heteroplasmic m.14484T>C mutation. Methods: A cross-sectional study. The objects of the study included a 31-year-old male LHON patient with the heteroplasmic m.14484T>C mutation (the proband) who visited Department of Ophthalmology in the Affiliated Central Hospital of Qingdao University in March 2015 and other 36 matrilineal relatives in a four-generation family (12 males and 24 females aged 2-81 years, median 27 years). The visual acuity, intraocular pressure, fundus, color vision, visual field, visual evoked potential and optical coherence tomography were evaluated in maternal members. The mitochondrial DNA (mtDNA) sequence of fragments including m.14484 loci was detected by Sanger sequencing in 33 members. The sequencing peaks were analyzed by QSVanalyzer software to get the heteroplasmy levels of m.14484T>C mutation. The mtDNA of the proband was amplified by PCR and sequenced. Assembled sequence of mtDNA was compared with the updated consensus Cambridge sequence. The differences in visual evoked potential, optical coherence tomography and heteroplasmy levels were compared between two groups by the t-test, and among multiple groups by the single factor variance analysis. Results: Among the 33 maternal members of the family, 4 patients, 28 carriers and 1 person without a mutation were confirmed. The penetrance was 12.5% (4/32) . In addition to 4 patients with obvious abnormality on the ophthalmic examination, 5 carriers also appeared anomaly on the electrophysiological and visual function examinations. Compared to carriers, the amplitude of P100 was obviously decreased in the LHON patients[ (5.6±2.6) μV vs. (15.6±9.6) μV, t=2.880, P=0.006]. Significantly reduced values were seen in the average retinal nerve fiber layer thickness[ (71±17) μm vs. (99±11) μm, t=5.969, P< 0.001], in each side of the sub-area macular thickness, and in the nasal side of the lateral sub-area macular thickness [ (260±16) μm vs. (291±12) μm, t=5.593, P<0.001] between the LHON patients and carriers. The heteroplasmic levels were 80%±3% in the LHON patients, and 27%±18% in the unaffected members;the difference was significant (t=-8.395, P<0.001). The average degree of heteroplasmy had no difference between male and female members (48%±34% vs. 35%±28%, t=-1.147, P=0.258). The average mutation load was 29%±14% in the second generation members, 36%±29% in the third generation members, and 51%±36% in the fourth generation members;the differences were not statistically significant (F=1.152, P=0.330). The difference in the heteroplasmic levels was not statistically significant between mothers and their offspring (31%±25% vs. 42%±32%, t=1.165, P=0.251). Compared to Cambridge consensus sequence, 41 mutations was found in mtDNA of the proband, of which, 10 were missense mutations, including mutations m.4216T>C and m.3394T>C. According to the phylogenetic tree, the haplotype of the proband was M9a (M9a1a1c1a). Conclusions: In the family with the heteroplasmic m.14484T>C mutation, clinical manifestations of LHON appear in the individuals whose heteroplasmic level is more than 75%, and all of patients show typical chronic optic atrophy on the ophthalmic examination. The carriers with the m.14484T>C mutation also appear anomaly on the electrophysiological and visual function examinations. The heteroplasmic level of m.14484T>C mutation has a tendency to increase during the transmission in the family. The primary mutation m.14484T>C coordinate mutations m.4216T>C and m.3394T>C to increase the penetrance and incidence of abnormal visual function in carriers. (Chin J Ophthalmol, 2018, 54: 526-534).

Amblyopia, Strabismus and Refractive Errors in Congenital Ptosis: a systematic review and meta-analysis

Congenital ptosis may be associated with abnormalities of visual development and function, including amblyopia, strabismus and refractive errors. However, the prevalence estimates of these abnormalities vary widely. We performed a systematic review and meta-analysis to estimate the prevalence of amblyopia, strabismus and refractive errors in congenital ptosis. Cochrane, Pubmed, Medline, Embase, and Web of Science were searched by July 2017. We used random/fixed effects models based on a proportion approach to estimate the prevalence. Heterogeneity would be considered signifcant if the p values less than 0.1 and/or I2 greater than 50%. Subgroup analyses, meta-regression analyses and sensitivity analyses were utilized to explore the potential sources of it. A total of 24 studies selected from 3,633 references were included. The highest prevalence was revealed for myopia with 30.2% (95%CI 3.0–69.8%), followed by 22.7% (95%CI 18.5–27.8%) for amblyopia, 22.2% (95%CI 7.8–63.1%) for astigmatism, 19.6% (95%CI 16.5–23.2%) for strabismus, 17.3% (95% CI 13.1–22.9%) for anisometropia and 4.0% for hyperopia (95%CI 1.8–7.1%). Significant heterogeneity was identified across most estimates. Our findings suggest that amblyopia, strabismus and refractive errors in congenital ptosis are present in much higher percentage. This study highlights the importance of early diagnosis and timely treatment of patients with congenital ptosis.

Frequent retinal ganglion cell damage after acute optic neuritis

BackgroundTo identify the extent of ganglion cell damage after first-time optic neuritis (ON) using the inter-ocular difference between affected and fellow eyes, and whether this approach is able to detect more patients suffering from ganglion cell damage than using absolute values. MethodsThirty-four patients with first-time unilateral ON were followed for a median 413 days. Patients underwent optical coherence tomography testing to determine ganglion cell plus inner plexiform layer thickness (GCIP). Ganglion cell loss was quantified as GCIP difference between ON-affected and fellow eyes (inter-GCIP) and was compared against measurements from 93 healthy controls (HC). Visual function was assessed with high contrast visual acuity; and standard automated perimetry-derived measures of mean deviation and foveal threshold. ResultsAt clinical presentation after median 19 days from symptom onset, 47.1% of patients showed early GCIP thinning in the ON-affected eye based on inter-GCIP. At the last visit acute ON was associated with 16.1 ± 10.0 µm GCIP thinning compared to fellow eyes (p = 3.669e-06). Based on inter-GCIP, 84.9% of ON patients sustained GCIP thinning in their affected eye at the last visit, whereas using absolute values only 71.0% of patients suffered from GCIP thinning (p = 0.002076). Only 32.3% of these patients had abnormal visual function. The best predictor of GCIP thinning as a measure of ON severity at the last visit was worse visual field mean deviation at clinical presentation. ConclusionInter-ocular GCIP identifies significantly more eyes suffering damage from ON than absolute GCIP, visual fields or visual acuity loss. Effective interventional options are needed to prevent ganglion cell loss.

Evaluating the Effects of Dry Eye Syndrome on Ocular Fatigue and Attentiveness

Purpose: This study was aimed to evaluate the effects of dry eye syndrome on ocular fatigue and attentiveness. Methods: This study targeted 512 subjects who did not have an abnormal visual function, did not wear contact lens, had corrective eyesight over 0.8, and were between 19 and 83 year olds (mean age of 40.27 years). General characteristics (i.e., sex, age, drinking, and smoking status), dry eye syndrome, the score of a survey on ocular fatigue, and sub-factors of attentiveness were tested and analyzed. Results: Among the subjects, 312 were women and the mean age of them was 40.27 years. The number of drinkers was 260 and there were more drinkers than non-drinkers. There were 438 non-smokers, which was more than smokers. Dry eye syndrome showed positive correlations with age, sex, smoking, drinking, and eye fatigue. Attentiveness showed significant differences with BET, NAR, OET, and RED, which were sub-factors, had significant effects on dry eye syndrome. Conclusion: People with dry eye syndrome showed lower attentiveness than those who without it and higher dry eye syndrome increased ocular fatigue.

Esotropia and Exotropia Preferred Practice Pattern®

Esotropia and Exotropia Preferred Practice Pattern®

Relation of accommodative microfluctuation with dry eye symptoms in short tear break-up time dry eye.

PurposeTo investigate accommodative microfluctuations (AMFs) and visual function in short tear break-up time (BUT)-type dry eye (DE) and non-DE subjects.MethodsThis prospective comparative study included 48 volunteers with DE symptoms (mean age 34.8 ± 5.5 years, age range 25–42 years) and 73 without DE symptoms (mean age 30.6 ± 4.7 years, age range 25–42 years). The eyes were divided into two groups: (1) DE group with DE symptoms and BUT ≤ 5 s and (2) non-DE group without DE symptoms and BUT > 5 s. We excluded eyes with Schirmer score ≤ 5 mm and positive keratoconjunctival epithelial damage. Tear evaluation, AMF, and functional visual acuity (VA) examinations were performed. AMF parameters included total high-frequency component (HFC), HFC with low accommodation for the task of staring into the distance (HFC1), and HFC with high accommodation for deskwork (HFC2). Functional VA parameters included starting VA, functional VA, visual maintenance ratio, and blink frequency.ResultsA total of 33 and 34 eyes were categorized in the DE and non-DE groups, respectively. Mean blink frequency and HFC1 values were significantly higher in the DE group than they were in the non-DE group.ConclusionsDEs with symptoms showed abnormal AMF and visual function, which may be associated with DE symptoms.

Bioinformatic analysis of retinal gene function and expression in diabetic rats

The aim of the present study was to investigate the changes in retinal gene expression at three time points and assess the underlying molecular mechanisms of diabetic retinopathy (DR) in a streptozotocin (STZ)-induced diabetes rat model using bioinformatics analysis. The gene expression profile of GSE28831 was extracted from the Gene Expression Omnibus database and differentially expressed genes (DEGs) were identified at three different time points (1, 4 and 12 weeks) using the limma package in R language. Gene ontology (GO) enrichment analysis of DEGs was performed followed by a principal component and pathway enrichment analysis of the selected DEGs along with protein-protein interaction network construction at the three time points. A total of 402, 105 and 213 DEGs were screened at 1, 4 and 12 weeks, respectively. In addition, the expression of 8 genes was identified to be significantly different at different time points, including cytochrome P450 2B2 (CYP2B2; downregulated gene; P=0.048; at 1 week), mannan binding lectin-associated serine protease-2 (MASP2; downregulated gene; P=0.044), lecithin retinol acyltransferase (LRAT; downregulated gene; P=0.015), retinal pigment epithelium (RPE)-specific protein 65 kDa (RPE65; downregulated gene; P=0.025), 11-cis-retinoldehydrogenase (RDH5; downregulated gene; P=0.04; at 4 weeks), mitogen-activated protein kinase 13 (MAPK13; upregulated gene; P=0.036), LRAT (downregulated gene; P=0.01) and RPE65 (downregulated gene; P=0.009; at 12 weeks). Furthermore, pathway enrichment and GO enrichment analyses revealed that DEGs at 4 weeks were primarily enriched in retinol metabolism and processes associated with visual functions, including ‘visual perception’ and ‘retinol metabolism’. DEGs, including CYP2B2, MASP2, LRAT, RPE65, RDH5 and MAPK13 may be potential targets for the diagnosis and treatment of DR. Thus, the current study demonstrated that abnormal visual functions occur at 4 weeks in STZ-induced diabetic rats. This may provide a scientific basis for the diagnosis and treatment of DR because DEGs may be used to facilitate the development of novel therapeutic strategies to diagnose and treat DR.

Visual dysfunction in Parkinson's disease.

Patients with Parkinson's disease have a number of specific visual disturbances. These include changes in colour vision and contrast sensitivity and difficulties with complex visual tasks such as mental rotation and emotion recognition. We review changes in visual function at each stage of visual processing from retinal deficits, including contrast sensitivity and colour vision deficits to higher cortical processing impairments such as object and motion processing and neglect. We consider changes in visual function in patients with common Parkinson's disease-associated genetic mutations including GBA and LRRK2 . We discuss the association between visual deficits and clinical features of Parkinson's disease such as rapid eye movement sleep behavioural disorder and the postural instability and gait disorder phenotype. We review the link between abnormal visual function and visual hallucinations, considering current models for mechanisms of visual hallucinations. Finally, we discuss the role of visuo-perceptual testing as a biomarker of disease and predictor of dementia in Parkinson's disease.

Recomendações sobre refração em crianças pré-verbais

Uncorrected refractive errors in children may generate abnormalities in visual function and affect their future academic studies, as well as their neuromotor development. Refractive errors are easy to diagnose and correct. An ophthalmologic examination with visual acuity measurements should be performed to arrive at a diagnosis of refractive error. Lenses should then be prescribed which could minimize these serious consequences for childhood development.