Developmental Eye Movement Research Articles

Evaluation of Visual Disturbances After Mild Traumatic Brain Injury-A One-Year Follow-up Study.

To examine the persistence of visual symptoms in mild traumatic brain injury (MTBI) during the first months after injury. It is important to recognize visual disturbances because they can delay return to normal activities, while they might be simultaneously treated by visual therapy. Here we describe the results from a 1-year follow-up study of visual disturbances after MTBI. The study group comprised 26 patients from the Brain Injury Clinic of the Helsinki University Hospital. Inclusion criterion was a high score (≥21p) on the Convergence Insufficiency Symptom Survey (CISS) at an appointment with a neurologist within 6months after injury. The patients underwent baseline vision evaluation at 4months on average and follow-up at 14months after injury. The evaluation included tests for visual acuity, near point of convergence, convergence facility, near point of accommodation, accommodative facility, motility, heterophoria, binocular vision, dynamic visual acuity, and fusional vergence width at near and far distances. Further assessments included the Rivermead Post Concussion Questionnaire for posttraumatic symptoms, a visual analog scale for visual fatigue, and the Developmental Eye Movement Test for saccadic eye movements. Both CISS and Rivermead Post Concussion Questionnaire scores improved significantly from baseline to follow-up. The overall level of visual fatigue according to visual analog scale score was lower at follow-up, but the increase in visual fatigue (comparing fatigue before and after assessment session) was significant both at baseline and follow-up. In visual function assessments, spontaneous recovery from baseline to follow-up could be seen in vergence facility and pursuit eye movement but not in near point of convergence, near fusion, distance fusion, heterophoria, and dynamic visual acuity. The results point out the importance of evaluation of visual disturbances after MTBI. Early detection of these disturbances may provide an opportunity to provide visual therapy.

Developmental eye movement test results of Hebrew-speaking children with cross-linguistic comparisons.

The developmental eye movement (DEM) test is designed to assess saccadic eye movements and visual-verbal automaticity in children. This study aimed to assess whether there is a need for independent DEM Hebrew norms and to compare DEM results for Hebrew-speaking children with eight other language norms. The DEM test was administered to 224 Hebrew-speaking children aged 6-13 years who met the inclusion criteria and read the numbers in Hebrew. Test C of the DEM was performed twice, once from right (R) to left (L) and once from L to R, in random order. Age group and language comparisons, including vertical and horizontal reading speeds, errors and horizontal/vertical (H/V) ratios in both directions were analysed. The participants were almost evenly distributed between the sexes (46.8% female). Statistically significant differences were found between age groups (6-9 and 10-13 years) for vertical and horizontal reading speeds and H/V ratios in both directions (p < 0.001). Older children, as compared to younger children, exhibited faster vertical and horizontal times, with fewer errors, as well as lower ratios (p < 0.001). No significant difference was noted between reading directions for horizontal time and H/V ratio within both age groups (6-9 year olds: p = 0.27 and p = 0.06; 10-13 year olds: p = 0.89 and p = 0.49, respectively). Comparison of DEM norms across languages showed significant differences, with post-hoc analysis revealing specific language-related variations. DEM results for Hebrew-speaking children had similar outcomes to both original English and French values. This study compared DEM results of Hebrew-speaking children and scores across nine languages. DEM test values for Hebrew-speaking children aligned with norms from other languages, particularly the French and original English norms, with consistent ratio scores. It is recommended for practitioners who test Hebrew-speaking children to continue using the original English norms and to enable the children to read using their preferred reading direction.

Oculomotor Behaviour in Individuals with Long COVID-19

Objective To determine, the impact of long COVID-19 on oculomotor behaviour. Design A case–control study. Setting Spanish Association of Persistent COVID. Participant Participants were 75 cases (64 women, 11 men, mean age 46.4 years ±8.9) and 42 controls (22 women, 20 men, mean age 53.5 years ±13.13). Intervention An eye-tracking test based on visual search paradigm and the Adult Developmental Eye Movement Test were used to evaluate the participants. Main measures The primary outcomes in the Adult Developmental Eye Movement Test were horizontal reading time, vertical reading time, and their ratio. And for the eye-tracking test the time to find the target, the duration, and the number of eye fixations. Results In cases and controls, eye movement test results were horizontal(Hadj) reading time 74.2 ± 22.7 s vs 52.0 ± 6.1 s (p < .0001); vertical(Vadj) reading time 67.6 ± 17.8 s vs 50.4 ± 6.9 s (p < .0001); Hadj/Vadj ratio 0.9 ± 0.1 vs 1.0 ± 0 (p = .0032), respectively; and eye-tracking test results were fixation number 11.3 ± 3.07 vs 3.51 ± 2.57 (p < .0001); fixation duration 2.01 ± 0.79 s vs 1.5 ± 0.4 s (p = .0013), and time to find target 24.5 ± 8.0 vs 18 ± 9.4 (p = .0034), respectively. Conclusions Data showed a lower performance in oculomotor behaviour in people with long COVID-19, compared to healthy individuals. It cannot be affirmed an ocular musculature dysfunction; the differentiated behaviour could be associated to cognitive alterations affected in these people. Both tests used could be an useful tool for the clinical assessment of these participants. Further studies are needed to explore the utility of these procedures.

The Computerized Developmental Eye Movement (DEM) Test: Normative Data for School-Aged Children.

The aim of the study was to determine the normative data of the computerized DEM test for school-age children in Latvia. The study analyzed data on the performance (test execution time, duration, number of fixations, and number of errors) of 291 children while completing the computerized DEM test. Eye movement fixations were recorded with a Tobii Pro Fusion video-oculograph (250 Hz). According to the results of the study, the performance of the computerized DEM test is 77 %. For the study, 1 SD (one standard deviation) was chosen as a criterion for determining test norms. In the study, the norms of the computerized DEM test in Latvia were developed in class groups-from 1st to 6th grade (aged 7 to 12 years), the results were summarized in a table as the minimum performance values of the computerized DEM test.

Eye Tracking-Based Characterization of Fixations during Reading in Children with Neurodevelopmental Disorders.

An efficient mode of evaluation for eye movements is the use of objective eye tracking systems combined with subjective tests (NSUCO or DEM), which are easily applicable across all age groups and in eye care clinical settings. The objective of this study was to characterize fixations during reading in two groups: a group of children with neurodevelopmental disorders (NDDG, 24 children, age: 6-12 years) and a group of children with oculomotor anomalies but without NDD (OAG, 24 children, age: 6-12 years). The results obtained were compared with those from a control group (CG, 20 children, age: 6-12 years). Specifically, the outcomes obtained with two subjective score systems, the Northeastern State University College of Optometry's Oculomotor (NSUCO) test and the Developmental Eye Movement (DEM) test, were compared with the objective analysis obtained through a commercially available eye tracker (Tobii Eye X, Tobii, Stockholm, Sweden). Specialized analysis software, namely Clinical Eye Tracker 2020 (Thomson Software Solutions, Welham Green, UK), was used. It was found that children with NDD had impaired oculomotor skills. A higher number of regressions, more fixations, and longer durations of fixations appear to be characteristic signs of this population group. Additionally, children with NDD took longer to complete the DEM test, as well as exhibiting more errors. The use of objective videoculographic systems for eye tracking and subjective tests like the NSUCO or DEM are good tools to assess saccadic movements, allowing the detection of oculomotor abnormalities in children with NDD.

Comparison of Visual Symptom Frequency and Occupational Issues Between Patients With and Without Concussion.

Occupational therapy practitioners' knowledge of and advocacy for clients with visual symptoms postconcussion can have a considerable impact on recovery. To compare the frequency of vision symptoms and occupational performance deficits in a sample of participants with and without concussion. Cross-sectional study. Sports medicine clinic. Adolescents and adults with concussion (n = 20) and musculoskeletal injuries (n = 19). Measures included monocular amplitude of accommodation, near point of convergence, Binocular Vision Assessment (BVA) computerized screening for phoria, BVA computerized screening for fusional vergence, the Developmental Eye Movement Test, the Canadian Occupational Performance Measure, and the Convergence Insufficiency Symptom Survey-Concussion Version (CISS-CON). We found significant differences between participants with and without concussion using the CISS-CON (p = .001), positive fusional vergence (p = .02), and near point of convergence (p = .02). Participants with concussion scoring above cutoffs on multiple measures reported poorer performance (p = .005) and satisfaction (p = .004) with valued occupations. Concussion has a detrimental effect on vision and occupation, and occupational therapy practitioners are well-positioned to assess and address issues arising from this relationship. Plain-Language Summary: Vision symptoms commonly experienced after a concussion are associated with reduced occupational performance and satisfaction and can have a considerable impact on recovery. Occupational therapy assessment for clients with concussion should include screening for vision difficulties.

Could driving help us to “see better”? A comparative assessment of saccadic efficiency, visual speed, and attention

BackgroundThis study aimed at comparing drivers’ and non-drivers’ results in the Adult Developmental Eye Movement with Distractors test (ADEMd) and the Useful Field of View test (UFOV).MethodsOne hundred and twenty Spaniards (mean age 50.90 ± 17.32 years) without eye disease voluntarily participated in this cross-sectional descriptive study. Participants in a single experimental session completed a questionnaire on sociodemographic, health, eyesight, and driving information. They also performed the ADEMd and UFOV tests randomly following standardized protocols. The ADEMd is a visual-verbal test that measures saccadic efficiency and visual attention. Brown-Forsythe (B–F) tests with Games-Howell post-hoc adjustments were conducted to assess differences between groups. Groups were formed according to sex, age (young adults, adults, and older adults), and driver/non-driver for further analysis. Additionally, associations between dependent variables were assessed through Spearman’s correlations.ResultsDrivers obtained significantly better results in the ADEMd compared with non-drivers. Non-significant differences between drivers and non-drivers were encountered in the UFOV. Additionally, significant differences were observed between sexes and age groups. It is worth highlighting that non-driver’s age significantly correlated with worse ADEMd performance (rho = .637 to .716). This correlation was non-significant in drivers. Similarly, reading hours significantly correlated with better ADEMd performance in non-drivers (rho = − .291 to − .363), but not in drivers. The only significant correlations between ADEMd and UFOV tests were found in drivers (rho = .307 to .410).ConclusionConsidering all the discussed results, it could be hypothesized that the driving task promotes abilities, such as oculomotor and cognitive function, which are relevant for the performance in the ADEMd. However, this hypothesis is based on correlational outcomes and further studies should causally assess this possible relation.

Ocular Motility Patterns in Intellectual Disability: Insights from the Developmental Eye Movement Test.

To measure the ocular motility parameters of the Developmental Eye Movement (DEM) test objectively, with an eye tracker in subjects with intellectual disability (ID). The DEM test was performed on 45 subjects with ID, while their eye movements were recorded with an eye tracker. Some objective parameters of ocular motility were obtained through each subtest (A, B, and C) of the full DEM test. There was a significant positive correlation between the saccadic speed (cc: 0.537; p = 0.001) and length (cc: 0.368; p = 0.030) of both eyes for the same subject. People with a higher percentage of ID exhibited a greater number of fixations, saccades, and errors, and took longer to perform the DEM test than those with a lower ID percentage, who had greater numbers of these parameters than subjects without ID. Subjects without ID exhibited faster saccades, with a higher amplitude, than subjects with ID. The eye tracker quantifies ocular motility parameters involved in the DEM test in subjects with ID. Both eyes' movements in subjects with ID were conjugated, exhibiting saccades of the same length and speed. All parameters were different in subjects with ID compared to those in subjects without ID, so normative tables specifically for subjects with ID are necessary.

Clinical reading-related oculomotor assessment in visual snow syndrome

PurposeVisual snow syndrome (VSS) is a complex neurological condition presenting with an array of sensory, motor, and perceptual dysfunctions and related visual and non-visual symptoms. Recent laboratory studies have found subtle, basic, saccadic-based abnormalities in this population. The objective of the present investigation was to determine if saccadic-related problems could be confirmed and extended using three common clinical reading-related eye movement tests having well-developed protocols and normative databases. MethodsThis was a retrospective analysis of 32 patients (ages 16–56 years) diagnosed with VSS in the first author's optometric practice. There was a battery of three reading-related tests: the Visagraph Reading Eye Movement Test, the Developmental Eye Movement (DEM) Test, and the RightEye Dynamic Vision Assessment Test, all performed using their standard documented protocols and large normative databases. ResultsA high frequency of oculomotor deficits was found with all three tests. The greatest percentage was revealed with the Visagraph (56%) and the least with the RightEye (23%). A total of 77% of patients failed at least one of the three tests. ConclusionThe present findings confirm and extend earlier investigations revealing a high frequency of saccadic-based oculomotor problems in the VSS population, now including reading-related tasks. This is consistent with the more general oculomotor/motor problems found in these individuals.

Vision impairment is common in non-hospitalised patients with post-COVID-19 syndrome

ABSTRACT Clinical relevance Vision-related problems can be part of longstanding sequelae after COVID-19 and hamper the return to work and daily activities. Knowledge about symptoms, visual, and oculomotor dysfunctions is however scarce, particularly for non-hospitalised patients. Clinically applicable tools are needed as support in the assessment and determination of intervention needs. Background The purpose of this study was to evaluate vision-related symptoms, assess visual and oculomotor function, and to test the clinical assessment of saccadic eye movements and sensitivity to visual motion in non-hospitalised post-COVID-19 outpatients. The patients (n = 38) in this observational cohort study were recruited from a post-COVID-19 clinic and had been referred for neurocognitive assessment. Methods Patients who reported vision-related symptoms reading problems and intolerance to movement in the environment were examined. A structured symptom assessment and a comprehensive vision examination were undertaken, and saccadic eye movements and visual motion sensitivity were assessed. Results High symptom scores (26–60%) and prevalence of visual function impairments were observed. An increased symptom score when reading was associated with less efficient saccadic eye movement behaviour (p < 0.001) and binocular dysfunction (p = 0.029). Patients with severe symptoms in visually busy places scored significantly higher on the Visual Motion Sensitivity Clinical Test Protocol (p = 0.029). Conclusion Vision-related symptoms and impairments were prevalent in the study group. The Developmental Eye Movement Test and the Visual Motion Sensitivity Clinical Test Protocol showed promise for clinical assessment of saccadic performance and sensitivity to movement in the environment. Further study will be required to explore the utility of these tools.

Impact of strabismus and binocular dysfunctions in the developmental eye movement test and test of visual perception skills: A multicentric and retrospective study

PurposeTo compare the performance in the Developmental Eye Movement test (DEM) and the Test of Visual Perceptual Skills (TVPS) between three groups: individuals with strabismus and amblyopia, patients with binocular and accommodative dysfunctions, and subjects with normal binocular and accommodative function. MethodsA multicentric, retrospective study including 110 children aged 6–14 years old was conducted to investigate the potential impact of strabismus, amblyopia, and different binocular conditions in DEM results (adjusted time in vertical and horizontal parts) and TVPS (percentiles in the seven sub-skills). ResultsNo significant differences were found in the different subtests of the vertical and horizontal DEM and all the sub-skills in the TVPS between the three groups of the study. We found high variability of performance in the DEM test between participants with strabismus and amblyopia compared with binocular and accommodative problems. ConclusionDEM and TVPS scores have not been found to be influenced by the presence of strabismus with or without amblyopia, nor by binocular and accommodative dysfunctions. A slightly correlation tendency with horizontal DEM and degree of exotropia deviation was observed.

Comparing the directional effect of number calling on the developmental eye movement test results in Hebrew‐speaking children

To evaluate the directional effect of number calling on the developmental eye movement (DEM) test in Hebrew-speaking children who read from right (R) to left (L). Previously, the DEM has been studied in nine languages, all read from L to R and has never been tested on Hebrew speakers. Healthy Hebrew-speaking children, aged 6-13 years were divided into two age groups (6-9, 10-13 years). Children had near visual acuity of 0.00 logMAR or better, no strabismus, stereoacuity ≤100 s of arc and near point of convergence ≤6 cm. The DEM test was performed twice, from R to L and L to R, randomly. Comparisons between age groups for horizontal and vertical reading speed and ratio between reading directions were analysed, as well as the correlation between age and directionality. A total of 92 children were included; 48 and 44 in the 6-9 and 10-13 year age groups, respectively. The mean vertical and horizontal time for both directions (R to L and L to R) in the younger group was significantly slower than the older group (p < 0.001). The older children showed no significant difference in the horizontal time reading from L to R and R to L. However, the younger children read more quickly in their native direction (R-L; 71.5 ± 25.9 s) compared with L-R (76.0 ± 31.4 s, p = 0.01). In both directions, the ratio was significantly higher in the younger age group. A negative correlation was demonstrated between age and reading ratio (p = 0.001). A clear directional preference of R to L was found in children under 10 years of age. We suggest administering the test from R to L in young Hebrew-speaking children. These results may also apply to young Arab- and Persian-speaking children who also read from R to L.

Eye-Tracker Study of the Developmental Eye Movement Test in Young People without Binocular Dysfunctions.

The purpose of this study was to evaluate ocular motility in normal young adults when performing the Developmental Eye Movement (DEM) test using an infrared eye-tracker in a sample of young subjects without visual dysfunctions. An optometric evaluation was carried out on 52 participants with a mean age of 21.00 ± 3.22 years to verify they did not have any binocular dysfunction, by completing a computerized version of the DEM test while their eye movements were recorded with an eye-tracker. A custom-written software was developed to analyse some specific parameters of ocular motility while performing each subtest (Test A, Test B and Test C) of the complete DEM test. The mean duration of the fixations was shorter in Test C (243.56 ± 46.18 s) than in Test A (493.52 ± 171.41 s) and Test B (484.20 ± 156.59 s). The mean adjusted horizontal (AdjHT: 35.24 ± 6.68 s) and vertical (VT: 33.58 ± 5.56 s) times were at the 45th and at the 40th percentile, respectively. In Test C, there was a high positive significant correlation between the saccadic speed (cc: 0.77; p < 0.001) and the saccadic length (cc: 0.74; p < 0.001) of both eyes. The eye-tracker is an objective method to evaluate the DEM test in subjects without binocular dysfunctions, measuring and quantifying ocular motility parameters that are impossible with the traditional subjective method. The eye movements of both eyes are conjugated in each subject, having saccades of the same length and speed.

Developmental eye movement strategies for decoding facial expressions of emotion

In our daily lives, we routinely look at the faces of others to try to understand how they are feeling. Few studies have examined the perceptual strategies that are used to recognize facial expressions of emotion, and none have attempted to isolate visual information use with eye movements throughout development. Therefore, we recorded the eye movements of children from 5 years of age up to adulthood during recognition of the six “basic emotions” to investigate when perceptual strategies for emotion recognition become mature (i.e., most adult-like). Using iMap4, we identified the eye movement fixation patterns for recognition of the six emotions across age groups in natural viewing and gaze-contingent (i.e., expanding spotlight) conditions. While univariate analyses failed to reveal significant differences in fixation patterns, more sensitive multivariate distance analyses revealed a U-shaped developmental trajectory with the eye movement strategies of the 17- to 18-year-old group most similar to adults for all expressions. A developmental dip in strategy similarity was found for each emotional expression revealing which age group had the most distinct eye movement strategy from the adult group: the 13- to 14-year-olds for sadness recognition; the 11- to 12-year-olds for fear, anger, surprise, and disgust; and the 7- to 8-year-olds for happiness. Recognition performance for happy, angry, and sad expressions did not differ significantly across age groups, but the eye movement strategies for these expressions diverged for each group. Therefore, a unique strategy was not a prerequisite for optimal recognition performance for these expressions. Our data provide novel insights into the developmental trajectories underlying facial expression recognition, a critical ability for adaptive social relations.

Binocular, accommodative and oculomotor alterations in multiple sclerosis

AbstractMultiple sclerosis (MS) is an acquired demyelinating and inflammatory neurodegenerative disease affecting the central nervous system (CNS). Clinical and subclinical ocular disturbances occur in almost all patients with MS. Among them, oculomotor, accommodative and binocular alterations have been reported in MS. Our research group has conducted a complete analysis of the visual and oculomotor function in several researches with MS patients conducted in the last 4 years, obtaining a characterization of some visual aspects of the patient with MS. Concerning the binocular function, several alterations have been detected in MS patients, with divergence at near distance and stereopsis the most affected parameters. Likewise, MS patients with previous optic neuritis present worse binocular vision. Symptomatology compatible with convergence insufficiency measured with the CISS (Convergence Insufficiency Symptom Survey) is frequently reported by MS patients, but not supported by signs that show clear trend to esophoria at near. This discrepancy between the signs and symptoms could be due to the peculiarities of the CISS questionnaire, including items that are also related to the cognitive function and other ocular abnormalities.Oculomotor alterations have been reported also in patients with multiple sclerosis (MS), especially saccadic dysfunctions. The indirect analysis of horizontal saccades with the Developmental Eye Movement (DEM) and King‐Devick tests shows that are affected by MS, with more level of alteration if there has been a previous episode of optic neuritis. Similar findings have been also reported by other authors using objective eye tracking or video‐oculographic systems. Specifically, the most reported saccadic alterations in advanced MS and clinically isolated syndrome (CIS) are saccadic dysmetry (41.7%) and impaired smooth pursuit (42.3%), which relates to prolonged saccadic latency, no matter if they have suffered or not optic neuritis or internuclear ophthalmoplegia (INO). An increase in saccadic latency has been even found in children with MS. Saccadic initiation time (SI time) and average inter‐saccadic intervals (ISI) are also higher in patients with MS. Furthermore, the first cause of acquired pendular nystagmus is MS.Finally, macular sensitivity measured by microperimetry has been found to be altered in MS patients, especially in eyes with previous optic neuritis. Likewise, a fixational instability characterized also my microperimetry is present in MS patients with optic neuritis, with more increase of the vertical axis of the fixation area than of the horizontal. The ratio of the disease also affects the patient fixation pattern.

An Exploratory Investigation of the Effect of a Sports Vision Program on Grade 4 and 5 Female Netball Players' Visual Skills.

Vision is one of the most complex and dominant sensory systems necessary for information feedback from the environment. Few studies have already reported a positive effect of a sport vision program on elite sport teams’ visual skills; however, few studies have focused on the effect of sport vision programs on children’s visual skills. Therefore, the aim of this study was to determine the effect of a sports vision program on Grade 4 and 5 female netball players’ visual skills. Girls (N = 25) with a mean age of 10.08 years (SD = 0.65) formed part of this study. A pre-test–post-test design was followed with a retention test. The eight-week sports vision program was executed twice a week for 60 min on the experimental group (n = 13). The Developmental Test of Visual–Motor Integration (VMI-4), the Wayne Saccadic Fixator (WSF) and the Developmental Eye Movement (DEM) test were used to evaluate the girls’ visual skills, hand–eye coordination, visual reaction time, peripheral vision and saccadic eye movements. No statistical differences were found between the two groups before starting with the sports vision program. After intervention, significant differences between the two groups were reported, with the experimental group performing better in hand–eye coordination (p = 0.001) and reaction time (p = 0.001). Results further indicated that the experimental group experienced significant improvements (p ≤ 0.05) in motor coordination, hand–eye coordination, reaction speed and visual tracking after intervention with significant lasting effects (p ≤ 0.05). The control group performed significantly worse in reaction time (p = 0.01). A sports vision program can be recommended for Grade 4 and 5 female netball players to improve certain visual skills.

The Developmental Eye Movement Test Does Not Detect Oculomotor Problems: Evidence from Children with Nystagmus.

SIGNIFICANCEThe Developmental Eye Movement (DEM) test, a test purported to assess oculomotor skills, does not detect eye movement disorder in nystagmus syndromes. The test should not be used for the clinical evaluation of oculomotor disorders.PURPOSEThe DEM test ratio compares a horizontal number naming subtest with a vertical one to identify oculomotor problems independent of a child's visual-verbal naming skills. Here, we tested the construct validity of this method by comparing scores of children with and without pathologic nystagmus. Such a nystagmus disturbs normal fixation and saccadic behavior because of the presence of involuntary rhythmic oscillations of the eyes. Therefore, if the ratio is indeed a comprehensive measure of oculomotor problems, children with nystagmus should show an increased ratio score.METHODSThe DEM test performances of normally sighted children (n = 94), children with ocular visual impairments (VIo; n = 33), and children with cerebral visual impairment (n = 30) were analyzed using linear regression. Part of the children with VIo and cerebral visual impairment had either fusion maldevelopment nystagmus syndrome (n = 8) or infantile nystagmus syndrome (n = 20), whereas the others showed no pathologic nystagmus.RESULTSThe times needed for the horizontal and vertical subtests were significantly different between children with normal vision, VIo, and cerebral visual impairment (P < .001). However, the presence of nystagmus did not add significantly to the horizontal and vertical times (P > .20), nor did it have an effect on the ratio (P > .10).CONCLUSIONSThe DEM test ratio is not sensitive to fixation and saccade abnormalities associated with nystagmus, indicating that it does not have general construct validity to detect true eye movement disorders. Although not suitable for the evaluation of oculomotor disorders, the subtests do have clinical relevance in the diagnosis of cerebral visual impairment.

Developmental Eye Movement (DEM) and King-Devick (K-D) Performance in Multiple Sclerosis.

Eye movement disorders have been reported in patients with multiple sclerosis (MS) as saccadic disturbances. Several methods have been described for the assessment of saccades, including the K-D and DEM tests. The performance of these tests also involves attention, language, and other brain areas which have been reported to be altered in MS patients. The aim of the study was to determine how developmental eye movement (DEM) and King-Devick (K-D) tests are affected in MS-patients. It was also to analyze whether a resolved episode of optic neuritis (ON) has a negative influence. Subjects with MS showed worse outcomes (higher times) in DEM test (72 (26) s and a K-D test (56 (22) s compared to healthy subjects (64 (7) s and 55 (11) s, respectively). However, a previous ON episode did not worsen the MS-times of DEM (80 (33) s or of K-D (62 (33) s. Horizontal saccades with the DEM showed differences between subjects with MS (with and without ON) and healthy ones (p < 0.05), whereas no such differences were found in the vertical saccades. According to the DEM instructions, MS patients would present heterogeneous oculomotor and non-visual disturbances. Regarding the K-D test, only the third card (the most complex one) showed differences (p < 0.05) between groups. These tests can capture impairment of attention, language, and other areas that correlate with suboptimal brain function in addition to the oculomotor dysfunctions present in subjects with MS.

Correlating Ocular Physiology and Visual Function with Mild Cognitive Loss in Senior Citizens in Taiwan.

Purpose: The transition of Taiwan from an aging to a super-aging society has come with a cost as more elderly now suffer from cognitive impairment. The main purpose of our study was to investigate if early detection can be developed so that timely intervention can be instituted. We analyzed the correlation of cognitive function with ocular physiology and visual functions between senior citizens aged 60 years or older in Taiwan. Methods: Thirty-six healthy subjects were recruited for the study. Addenbrooke’s cognitive examination III (ACE-III), binocular functions (including objective and subjective refraction, distance and near dissociated phoria, stereopsis, contrast sensitivity, adult developmental eye movement (ADEM), and ocular physiology (by using optical coherence tomography, OCT, and macular pigment measurement, MPS) were performed, and the data were analyzed via independent t-test, chi-square test, Pearson correlation, linear regression, and ROC (receiver operating characteristic) curve. Results: Data analysis showed that (1) patients with poor eye movement had a strong correlation with the total score and all dimensions of cognitive functions, (2) the thickness of the macula had a strong correlation with attention and memory, and (3) patients with poor eye movement and poor stereopsis in combination with thinner inferior macula appeared to have lower cognitive abilities. Discussion and Conclusions: Cognitive dysfunction is not readily identified during the early stage of cognitive decline. The use of simple and inexpensive ADEM or stereopsis test and comparing the OCT results that are popular in optometry clinics for reference can be diagnostic in identifying patients with mild cognitive impairments. With the combined use of macular pigment density or retinal thickness measurements, it was possible to effectively predict the early degradation of cognition.

Visual-processing deficits in children with neurofibromatosis type 1: A clinical marker of reading difficulties.

Today's estimates indicate that nearly 50% of children with Neurofibromatosis type 1 (NF1) suffer from reading disabilities, with a high impact on their academic achievement. In addition to the well-documented importance of phonological skills in reading acquisition and neurodevelopmental disorders, visual-attention processes also appear as important factors in learning to read. The present study aimed at assessing the role of visual-processing dysfunction in the high prevalence of reading disabilities in NF1 children and providing a useful tool for clinician in the early detection of reading impairment in this neurogenetic disorder. Forty-two children with NF1 and 42 typically developing children (TD) participated in the study. All were right-handed and did not present intellectual disability or attention deficit hyperactivity disorder. Visual-attention processes were assessed with the Developmental Eye Movement (DEM) test, together with the NF1 children's reading level. NF1 children with and without reading disabilities were then compared. The results showed that visual-processing deficits were highly present among the NF1 children included in our study. Furthermore, poor readers with NF1 presented an increased risk of visual-processing deficits compared to peers. This finding supports the role of visual-processing deficits in the reading difficulties encountered in nearly half of children with NF1. Finally, in NF1 children without intellectual or attention disability, visual-processing deficits emerge as one of the clinical markers of reading disabilities. The study holds important clinical implications both for the identification, by providing a useful screening tool, and the management of reading disabilities in NF1 children.