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Background: Early diagnosis is the main requisite for rehabilitating children suspected to suffer from dyslexia, and self-reports may be as reliable as ordinary screenings, but far less expensive. Research shows that the visual function can be involved in the pathogenesis of dyslexia so that self-reports should inquire about visual signs as well. A questionnaire made of 21 items that provide scores based on the visual signs commonly reported by dyslexics and on the most relevant comorbidities according to the literature has been devised. The aim of this exploratory study is to evaluate its potential for the early identification of dyslexic children. Methods: The AAP-DD is a set of 21 items subdivided into 4 sections that inquire about visual signs (section S), fatty acid deficiency, inheritance of dyslexia, and related conditions in children and parents. Each item is assigned a specific visuomotor and visuosensory weight in the form of a coefficient. The parents of twenty-three dyslexic children (9.34±0.80 years) and twenty-four normal readers filled the questionnaire. To assess the correspondence between the outcome of the questionnaire and the actual visual function of each participant, spatial relationship perception and ocular movements have been tested psychophysically. Results: The score of the dyslexic sample was almost double (i.e. worse) compared to the control group (P

The damage to the visual field is the main outcome of glaucoma. Basically, there are two different approaches to establish the rate of the functional loss in this clinical condition: event-based analysis and trend-based analysis. The event-based analysis, that relies on the occurrence of pre-established events to detect the progression of the visual field damage, cannot quantify the decay rate of sensitivity. In turn, the trend-based analysis, that aims to measure the rate of progression according to linear regression models, requires a long follow-up. Despite considerable effort, there is still no consensus on the optimal procedure, and a gold standard is still missing. This paper provides a quick overview of the topic as a tribute to the researchers engaged in this field.

Aims: A computational model aimed to estimate the proportion of visual/motor deficits (first-order defects) and visual-motor abnormal integration (second-order defect) in dyslexic children is described. Study Design: Single-masked case-control study. Place and Duration of Study: Sample: Service of Neuro-Ophthalmology, University of Turin, between December 2017 and November 2018. Methodology: Twenty subjects (age 8-10) were administered a set of tests that recruit the visual and motor domain in different proportions. The score obtained in each trial is weighed by the correspondent share of visuoperceptive and motor recruitment. This way two indexes are obtained: Eta (h) and Mu (m), that quantify the expected and estimated damage of the two functions across the range of average performance. The difference between the expected and estimated level of damage in the two domains represents the quota of selective visuoperceptive / motor impairment of the subject. In turn, no or negligible difference in the presence of abnormal z-score would reveal impaired visual-motor integration with no evident visual or motor damage. Results: The model detected a prevalent first-order defect in the visuo perceptive or motor domain in 58% of the cases (visuo perceptive alteration: 27%, motor alteration: 73%), and a prevalent second-order defect in the remaining 42% of the subjects. Internal consistency was adequate for research and screening purpose (Cronbach’s coefficient alpha: from 0.77 to 0.84). Conclusion: The Eta/Mu model seems a promising tool to detect cases of visual and motor alteration as well as the level of visual-motor integration in dyslexic children. Further effort is needed to improve test-retest reliability by examining larger samples, so as to make it suitable to customize the rehabilitation program of children suffering from learning disabilities.

To describe a novel optokinetic visual acuity estimator (Oktotype) and to report the preliminary results obtained in poorly and non-collaborative subjects. Eleven series of symbols arranged horizontally and moving from left to right at a constant rate were displayed. In each sequence, the size of the stimuli was reduced logarithmically. By using this paradigm, the objective visual acuity was computed in 26 normal subjects as the minimum size of the symbols able to evoke the optokinetic response. In the preliminary phase, three contrast levels were tested, with white noise added to the first five sequences so as to normalize the overestimate found at the lower-half range of the acuity scale. Subsequently, the correspondence between subjective and objective visual acuity was compared in 10 poorly collaborative subjects, and the agreement between optokinetic and Teller visual acuity was measured in six non-collaborative subjects. The best agreement is provided by the minimum contrast level (20%) (R 2 = 0.74). The correspondence between the two techniques is satisfying both in the normal and in the poorly collaborative sample (concordance correlation coefficient: 0.85 and 0.83, respectively). In the non-collaborative group, the concordance correlation coefficient between Teller acuity and OKVA ranged between 0.79 (test) and 0.85 (retest). Test–retest reliability was very good for the Oktotype (K: 0.82), and better than the Teller test (K = 0.71), even if it was lower compared to Snellen acuity (K = 0.95). The Oktotype seems promising to predict Snellen visual acuity in normal and poorly collaborative subjects.

Introduction Early diagnosis is the main requisite when dealing with subjects suspected to suffer from neurodevelopmental disorders, especially reading disability. In this respect, self-reports are a promising tool and could prove to be as reliable as ordinary screenings, with the advantage of low cost and low time consumption. Since the last decades, the perceptual and visuomotor function are believed to be involved in the pathogenesis of developmental dyslexia; therefore, specific elements related to an alteration of the sensorial and visuomotor domain in the familial and personal medical history could reveal a risk to develop this condition at a pre-examination phase. Yet, rather than evaluating the perceptual and motor function, the self-reports presented so far investigate the presence of dyslexia traits and comorbidities in parents, relatives, and in the sons. The Analytic Anamnestic Protocol (AAP), specifically devised to assess the perceptual and visuomotor function in children, revealed higher visuomotor and sensorial scores in samples suffering from congenital cerebral lesions, Down syndrome, and reading disability compared to a control group. Sensibility and specificity were acceptable, as shown by the receiver operating characteristic (ROC) curves. In this paper, a modified version of the AAP (the AAP2) targeting more specifically developmental dyslexics is presented, along with the preliminary results obtained in a group of school-age disabled readers. Methods The AAP2 is made of 25 questions divided into four sections (family, general, past and recent specialist medical history). In addition, seven questions inquiring about aspects related to the lexical difficulties (developmental dyslexia (DD) section) have been included. Like the previous version, each answer is assigned a perceptive and visuomotor score. The self-report was administered to 37 normal subjects (median age: nine years), and 34 dyslexic children (median age: eight and a half years). Results Visuomotor and sensory scores in the dyslexic sample was consistently higher than in the controls in the recent specialist medical history and in the DD section (Welch test: visuomotor (VM) t = 7.02, p < .0001; sensory (VS) t = 7.39, p < .0001) with the visuosensory domain more involved than the visuomotor function (T-test: t = 4.70, p < .0001, and t = 7.06, p < .0001, respectively). The sensibility and specificity of the recent specialist medical history of the AAP was 94.12% and 77.78%, respectively. Sensibility and specificity of the DD section DD were 100% and 80%, respectively. Conclusion The AAP2 is a promising tool to screen subjects at risk for developmental dyslexia at the beginning of primary school. Like the previous version (also in this modified questionnaire), the main weakness remains the heuristic criterion adopted for the assignment of the scores.

To report the ophthalmological risks of space travel. The literature about the effect of microgravity and cosmic radiation on the human eye has been reviewed, focusing on the so-called “spaceflight related neuro-ocular syndrome (SANS)”, and possible remedies. The eye is the major candidate to suffer from the adverse space conditions, so much so that SANS is the main concern of the National Aeronautics and Space Administration (NASA). SANS, that affects astronauts engaged in long-duration spaceflights, is characterized by optic nerve head swelling, flattening of the posterior region of the scleral shell, choroidal folds, retinal cotton wool spots, and hyperopic shift. Even if it seems related to an increased volume of the cerebrospinal fluid in the brain and the optic nerve sheaths, its pathogenesis is still unclear. In addition, cataract is related to the effect of galactic cosmic rays on the lens. Centrifuges, pressurizing chambers, and mechanical counter-pressure suits have been advanced to counteract the upward fluid shift responsible for the SANS syndrome. Shields with a high content of hydrogen, magnetic shielding systems, and wearable radiation shielding devices are under study to mitigate the exposure to galactic cosmic rays. Since 1961, the year of the first manned mission outside the Earth, history has shown that the human being may venture in space. Yet, visual impairment is the top health risk for long-duration spaceflight. Effective remediation is mandatory in anticipation of long space missions and Moon and Mars colonization.

To estimate objective visual acuity in subjects suffering from cataract and age-related macular degeneration via the optokinetic response evoked by a non-conventional induction method (oktotype); in addition, to compare such objective outcome with the subjective acuity based on the ETDRS charts. Patients were presented with 13 sequences of symbols arranged horizontally to form a serial pattern, moving from left to right at a constant rate. In each sequence, the size of the stimuli was reduced progressively, while the operator checked for the disappearance of the optokinetic response via a small video camera mounted on the test lens frame. The minimum angular size of the serial pattern able to evoke the optokinetic response (MAER) was referred to as the objective visual acuity of the subject. Correlation between logMAER and logMAR was significant in the cataract and macular degeneration group ( $$R_{\text{cat}}^{2}$$ = 0.70, p

Purpose A model aimed at detecting the proportion of visuoperceptive and visuomotor coordination impairment in children with ascertained or suspected learning disability is described. The final purpose is to provide customized rehabilitation programs. Methods In this pilot study, four children (8-9 years) were administered a set of standardized tests to evaluate their ability to perform visuoperceptive and visuomotor tasks. Depending on the individual outcomes, two indexes have been computed from the resulting z-scores: η (Eta) that quantifies the visuoperceptive impairment, and μ (Mu) that expresses the alteration in visuomotor coordination. Results A condition of abnormality was evident in each patient: Subjects 1 and 3 suffered mainly from a visuoperceptive alteration (η higher than expected), while Subject 4 had reduced visuomotor coordination (μ higher than expected). Subject 2 showed balanced visuoperceptive and visuomotor impairment. Based on the obtained η and μ values, each child underwent a customized rehabilitation treatment, then they were examined again. At re-test, η or μ turned balanced and z-scores improved in the four patients. Conclusions The Eta/Mu model is effective in detecting the type of damage by quantifying the share of visuoperceptive and visuomotor coordination involvement in dyslexic children, allowing a customized rehabilitative approach. Such an approach, focused on treating the function found to be defective, appears to be effective in rebalancing individual visuomotor and visuoperceptive skills; it should, therefore, be taken into consideration when updating the rehabilitation plans of learning disabled children.

Aims: To evaluate the effectiveness of visual training aimed at improving the visual function in dyslexic children suffering from increased crowding. Study Design: Single-masked crossover pilot study. Place and Duration of Study: University of Turin and the Gradenigo Hospital, Department of Ophthalmology, Turin, between March and November 2014. Methodology: 14 reading-impaired children (8-11 years) with increased paracentral crowding underwent a visual training devised to improve reading fluency by reducing lateral masking. Patients were asked to recognize trigrams of letters with different inter-letter spacing displayed at variable eccentricities on both sides of the fixation point (trigram training). Since any visual task chosen as a placebo could show some rehabilitative effect, placebo training was replaced by a period of reading practice, when reading exercises were recommended to be done at home. Results: After two weeks of training, in the recruited sample reading rate for words increased from 1.88 syl/sec (SD:±0.74) to 2.19 syl/sec (±0.86). Reading rate for non-words improved from 1.13 (±0.39) syl/sec to 1.28 (±0.42) syl/sec. No significant improvement was found after the period of Original Research Article Aleci et al.; OR, 3(3): 85-94, 2015; Article no.OR.2015.015 86 reading practice both at words and non-words. Analysis of variance showed a significant reading exercise x trigram training effect both for words (P= .0004) and non-words (P= .0001) in the recruited sample of disabled readers. To confirm the ameliorative effect of training (not being involved a placebo), a second, smaller sample has been administered the reading practice before the treatment. In this second group no substantial change in reading fluency was found after two weeks of reading practice, whereas after the trigram training reading rate improved by 11.8% at words and 29% at non-words despite, probably due to the small size of the second sample, results did not reach statistical significance. Conclusion: Trigram visuoperceptive training demonstrated to be effective in improving reading rate in dyslexic children suffering from reinforced crowding. The ameliorative effect of the rehabilitation is found to be sharper in patients showing abnormal crowding compared to the nonclassified dyslexics trained in a previous study. Interdisciplinary rehabilitative approach of developmental dyslexia should therefore consider also visuoperceptive rehabilitation aimed at normalizing lateral masking.

Although in experimental psychology the fixation/saccadic sequence is a main topic of debate, so far in the clinical ophthalmological field such an argument has raised relatively few interest. Nevertheless, studying the possible alterations of the saccadic rate and of the positioning of fixations when analyzing a visual scene may illuminate on the source of reading difficulty in a variety of patients, like dyslexic children or those affected by hemianopia as well as central visual field impairment. Recently, new light has been shed on the saccadic/fixation dynamics, both in the temporal and spatial domain. In addition, according to recent findings a visuoperceptive distortion could potentially affect the saccades/fixation sequence, making the matter much more complex than expected. The aim of this article is therefore to describe the saccadic/fixation seesaw under the temporal and spatial perspective and to disclose the possible influence of visuoperceptive impairments.

Aims: To evaluate the effectiveness of visual training aimed at reducing crowding indyslexic children.Study Design: Single-masked crossover pilot study.Place and Duration of Study: University of Turin and the Gradenigo Hospital,Department of Ophthalmology, Turin, between January and November 2013.Methodology: 15 dyslexic children underwent a visual training devised to reducecrowding. Patients were asked to recognize trigrams of letters with different spacingdisplayed at different eccentricities on both sides of the fixation point. As a placebo halfof the sample was administered a contrast sensitivity test. Average reading rate forwords and non-words with different interletter spacing was measured before and afterthe visual training and the placebo. The sample was divided into two subgroup: G1, whowas first administered the training, and G2, who underwent first the placebo trial.Results: After the training in G1 reading rate for words increased from 1.54 syl/sec(±0.60) to 1.74 syl/sec (± 0.64) (P= .001). Reading rate for non-words improved from0.94 (0.68-1.55) syl/sec to 1.03 (0.85-1.63) syl/sec. No significant improvement wasfound after the administration of the placebo (T2) when testing words and non-words.Original Research Article

Aims: To assess sensory ocular dominance of children by means of a novel psychophysical technique (Domitest-S). Study Design: population study. Place and Duration of Study: Department of Ophthalmology, The Gradenigo Hospital, Turin, between June 2012 and June 2013. Methodology: Thirty sequences of stimuli (15 for the left eye and 15 for the right eye) were administered in dichoptic conditions to 152 pupils (mean age: 9 ± .8 years). The task was to detect the target (a checkerboard-like pattern arranged so as to form an “X”) embedded in a series of null stimuli (checkerboard-like patterns randomly arranged). Left and right proportion correct responses were computed and an index of dominance laterality, the Balance Value (BV), expressed as the right minus left proportion correct responses was introduced. A second index based on the total amount of percent correct responses, the Interocular Inhibitory Index (III) was computed to provide a measure of reciprocal binocular suppression. Results: The frequency distribution of sensory dominance was not normal, but skewed on the left (KS=.17, P

Aims: There is evidence that the deprivation of a sensory system at early developmental stage may lead to a functional change of the remaining one(s). Even if this process has been widely studied, results are still controversial. In particular, the auditory system might affect the oculomotor control, since saccades or fast eye movements (FEMs) and slow eye movements (SEMs) are modulated by the cochleo-vestibular input. It follows that hearing impairment would affect the SEM and saccadic pattern. Therefore, in this study FEMs and SEMs have been evaluated in congenital deaf subjects in order to state whether early auditory deprivation has influence on the oculomotor function. Study Design: Case-control study.

A consistent body of literature maintains that the use of monocular sector prisms may enlarge the field of view of hemianopic patients, leading to a substantial improvement of their everyday life. Despite the potential interest, as far as we know clinical trials focusing on this last topic are few. Indeed, the effect of the monocular sector prisms on the whole extent of the binocular visual field and on the differential light sensitivity of the monocular ipsilateral visual field has not been fully investigated. This study aims at estimating the effect of a particular monocular prismatic sector, halfmoon shaped, placed on the carrier lens on the side of the loss, on the differential light sensitivity as well as on the binocular visual field extent in hemianopic patients. The only significant ameliorative finding is the reduction of the gradient of sensitivity between the blind and the responsive side of the monocular visual field in the eye under the prism. However, it fails to increase the differential light sensitivity of the eye fitted with the prism. Likewise, the extent of the binocular visual field did not change significantly, irrespective whether an adaptation period had occurred or not. In conclusion, our results suggest that the ameliorative effect in hemianopes provided by the of prismatic treatment depends on the enlargement of the field of view rather than on substantial enlargement of the visual field and/or on increased light sensitivity.

Purpose of the study was to compare Rarebit Perimetry (RP) with Standard Automatic Perimetry (SAP) in patients with ischemic retrochiasmal lesions. Seventeen patients with homonymous hemianopia underwent SAP and RP. Correlation between the two techniques was evaluated, congruent defects were quantified in the spared hemifield and residual vision areas were investigated in the blind hemifield. A strong correlation was found between SAP and RP. In the spared hemifield, RP detected congruent defects in a higher percentage of cases. Residual detection function has been found at RP in 69,2 % of perimetrically blind visual field quadrants as assessed by SAP. In conclusion, RP appears to be useful to assess visual function in hemianopic patients. As compared to SAP, it seems able to detect small congruent defects in a higher percentage of cases. Finally, a certain residual function seems to be present at RP in the blind regions of the visual field, however, for this finding further demonstrations are required.

Spatial relationship perception (SRP), defined as the function able to detect the difference between the perceived extent of a shape along the x/y cardinal coordinates, has been investigated in 42 eyes of 21 emmetropic subjects by means of a psychophysical test conceived on purpose. Aiming to the highest sensibility and since curvature detection is reckoned as an hyperacuity, elliptical stimuli have been chosen to measure the spatial relationship anisotropy (SRA) in the visual system. Observers turned out to be able to detect curvature differences along the elliptical contour as low as 33.6 sec arc, which in terms of SRP means an aspect ratio (i.e. the ratio between the height and the width of the ellipse) as low as 1.0022-1.0035. By comparing these results with those obtained in previous investigations from other curvature discrimination tasks, it is argued that recognition threshold is conditioned by the amount of space anisotropy of the visual system. Indeed, in about half of the recruited subjects, vertical/horizontal anisotropy is found to a certain extent and such SRA correlates with the recognition threshold (r= 0.69, p

According to wide literature, a global impairment in the temporal and spatial domains as well as an increased crowding effect is common of dyslexics. The aim of the study was to evaluate if such subjects suffer from a more general impairment of spatial relationship perception (SRP) and in particular from anomalous spatial relationship anisotropy (SRA) thus accounting both for their global perceptual distortions and abnormal crowding. SRP of 39 young disabled readers and 23 normal subjects were measured by a specifically designed psychophysical technique based on circular and elliptical target recognitions. A general impairment of SRP characterized by increased horizontal/vertical anisotropy was found in the dyslexic sample compared to the controls. In the second part of the experiment, reading efficiency and reading time were measured by MNREAD(©) reading cards in standard conditions and after increasing horizontal spatial extension of the sentence by different values. We suppose this modification could well compensate the abnormal anisotropy found in dyslexics. Data obtained in the two groups were compared. A strong correlation between reading efficiency (a parameter we have specifically devised) and horizontal spatial text relationship values were present in the patients (r=.87, p

Visual aura is the most common feature associated with migraine, though it can occur separately. In both cases it often represents a dramatic event, especially for patients who experience it for the first time. Besides, its subjective characteristics may illuminate on the functional architecture of the visual cortex. Repetitive events of migraine and visual aura have been suggested to affect the visual system in the long run, both on the cortical and precortical level. In effect, objective investigation of visual functions in patients support the idea that a selective damage does occur, so that more attention to visual examination seems to be justified. In this paper, subjective and psychophysical aspects of visual aura are examined, lastly highlighting and discussing the interesting correlations found between this condition and normal-tension glaucoma.