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BACKGROUND/PURPOSE To describe the association between autosomal dominant Best disease and peripapillary angioid streak-like changes. METHODS Case report of two siblings. RESULTS A 76-year-old Caucasian male was referred for evaluation of bilateral macular changes and worsening visual distortion over the preceding 2 years. Best corrected visual acuity (BCVA) measured 20/30 in the right eye and 20/80 in the left eye. Funduscopic examination revealed multifocal yellow lesions in the posterior pole that were hyper-autofluorescent on short-wavelength excitation and corresponded with subretinal hyperreflective material on optical coherence tomography. The posterior pole examination was interesting due to the juxtapapillary involvement of the vitelliform lesions as well as the presence of bilateral peripapillary angioid streak-like changes despite no history of conditions associated with angioid streaks. On further workup, an electro-oculogram revealed reduced Arden ratios and a known heterozygous missense mutation in BEST1 (c.903T>G; p.D301E) was found. The patient's 69-year-old younger brother was brought in and found to have a remarkably similar phenotype, including the presence of angioid streak-like changes associated with the same BEST1 mutation. CONCLUSIONS These two cases demonstrate the possibility of late-onset multifocal vitelliform disease due to dominantly inherited BEST1. A consistent phenotype in this family with macular lesions extending into the peripapillary region, associated with angioid streak-like changes, suggests susceptibility of this region to changes in dominant BEST1-vitelliform macular dystrophy.

SIGNIFICANCE This study demonstrates the importance of routine multimodal imaging for the diagnosis of choroidal neovascular membrane secondary to torpedo maculopathy. CASE REPORT A 63-year-old woman with a history of torpedo maculopathy presented with recent-onset symptoms of visual distortion in the right eye. Multimodal imaging modalities revealed the presence of a choroidal neovascular membrane. The choroidal neovascular membrane was treated, and the patient was subsequently followed up to monitor the retinal appearance over time. Significant structural restoration of the macular anatomy with overall functional improvement was seen. CONCLUSIONS Although torpedo maculopathy is often a benign diagnosis, complications such as choroidal neovascular membrane can occur. Choroidal neovascular membrane formation is well documented in younger patients with torpedo maculopathy; however, we present a rare case of choroidal neovascular membrane in an elderly individual. Multimodal imaging proved instrumental in the early detection and management of this infrequently reported complication.

Introduction Teaching dermatology to medical students entails a series of lectures, pictures, and hands-on skin examinations to convey a sense of skin features and textures, often by use of simulated skin models. However, such methods can often lack accurate visual and tactile texture representation of skin lesions. To facilitate learning, we have developed a smartphone-based skin simulation model, which provides a configurable visual and tactile sense of a lesion by using the ubiquitous availability of smartphone-based mobile platforms. Methods A polydimethylsiloxane (PDMS) overlay was used as a configurable translucent elastomer material to model the stiffness and texture of skin. A novel custom smartphone-based app was developed to capture images of various skin lesions, which were subsequently displayed on a tablet or second smartphone, over which the PDMS model skin elastomer was placed. Using the local Bluetooth connection between mobile devices, an iterative feedback algorithm corrected the visual distortion caused by the optical scattering of the translucent elastomer, enabling better virtual visualization of the lesion. Results The developed smartphone-based app corrected the distortion of images projected through the simulated skin elastomer. Surface topography of the developed PDMS elastomer provided a more accurate representation of skin texture. Conclusions In this investigation, we developed a smartphone-based skin lesion visualization app with a simulated skin elastomer for training/education in not only dermatology but also all general medical specialties that examine the skin. This technique has the potential to advance the educational experience by giving students the ability to see, touch, and feel pragmatic skin textures and lesions.

Purpose: To establish the time course of the subjective visual function changes during the first month of orthokeratology treatment in myopic children, and to investigate how the time course variations are associated with the objective optical quality changes and the axial length growth (ALG) after 1 year of treatment.Methods: A total of 58 myopic children aged from 8 to 16 years participated in this self-controlled prospective study. All subjects were fitted with designed spherical four-zone orthokeratology lenses. Subjective visual function was evaluated with orientation discrimination threshold (ODT), and objective optical quality was quantified with the high-order aberration root-mean-square (HOA-RMS) and the changing speed of HOA. The measurements were done before the lens fitting and 1 day, 1-, 2-, and 4-weeks after lens wear. Axial length was obtained at baseline and 1-year follow-up, and ALG was defined as the difference. One-way ANOVA was conducted to compare the difference for statistical analysis.Results: After lens fitting, the ODT time courses peaked on day 1 in 28 children, 1 week in 15 children, 2 weeks in 11 children, and 4 weeks in 4 children. In contrast, the HOA-RMS steadily rose during the first month, and the changing speed of HOA was only transiently elevated on day 1 after the initial lens wear. The ALG was 0.12 ± 0.20 mm in subjects whose ODT peaked at day 1, 0.08 ± 0.09 mm in subjects whose ODT peaked on 1-week, and 0.12 ± 0.15 mm in subjects whose ODT peaked on 2-week or later. There was no difference in axial growth among the subjects whose ODT peaked at different days (P = 0.734).Conclusion: While half ODT time course resembled the changing speed of HOA with a transient elevation on day 1, about a quarter of the ODT time course resemble the steadily rising of HOA-RMS, and the rest was located in the middle. The ALGs in children with different types of ODT time courses were similar.

BACKGROUND AND OBJECTIVE: To evaluate a novel digital method of metamorphopsia quantification in patients with symptomatic visual distortion as determined by M-CHARTS. PATIENTS AND METHODS: In this institutional review board-approved, prospective, cross-sectional observational study, subjects were presented with an objectively straight dotted line that bisects a central fixation point. The subjects digitally altered the line's contour until it appeared straight. Calculation of the area between the original objectively straight line presented to the subject and their newly manipulated line was performed to determine the manipulated area under the curve (M-AUC). RESULTS: Sixty-two percent of test targets were fully or significantly straightened by affected subjects. M-AUC was significantly correlated with M-CHARTS scores in both the horizontal ( P < .001) and vertical ( P = .05) orientations. CONCLUSIONS: The deformation of an objectively straight line by a subject with metamorphopsia may be a viable way of both quantifying and spatially characterizing visual distortions. [ Ophthalmic Surg Lasers Imaging Retina . 2020;51:11–20.]

Identifying diabetic retinopathy in its early stage using fundus imaging is the active area of biomedical research. However, fundus images are usually related to uneven lighting and some visual distortion factors. Choosing a suitable preprocessing mechanism is crucial for improving fundus image quality to highlight hidden information and weigh the essential features such as retinal blood-vessels and exudates to analyze diabetic retinopathy. However, selecting an appropriate preprocessing mechanism is challenging to perform a comprehensive enhancement operation. It cannot be achieved using single techniques because each denoising and enhancement techniques are associated with a few advantages and limitations. Therefore, the resulting images may associate with other different artifacts, even after preprocessed. To address such issues, modeling a universal framework is designed to integrate different preprocessing techniques to evaluate fundus image enhancement. Apart from this, the proposed study also explores the applicability of optimization in image enhancement by using a swarm-based stochastic optimization algorithm. The performances of preprocessing techniques are evaluated against PSNR, and brightness is quantified in the enhanced image. This paper’s main contribution is that it offers a flexible design of preprocessing framework that can meet on-demand image enhancement based on different preprocessing requirements to standardize the quality and interpretation of fundus imaging for diabetic retinopathy analysis.

Purpose: To investigate the use of software-generated corrections in neutralizing perceived distortions in age-related macular degeneration. Methods: A tablet-based application was utilized to elicit distortions. Five subjects (seven eyes: neovascular age-related macular degeneration and three eyes: non-neovascular age-related macular degeneration) traced the reference lines, and their distortion traces were recorded. To counter distortion, a software-generated trace was re-traced by subjects to produce a corrected trace. Final traces were superimposed on optical coherence tomography images and following distances calculated: (a) dDT: distance between distortion trace and reference line; (b) dGT: distance between software-generated trace and corrected trace; (c) dCT: distance between corrected trace and reference line. Mean percent improvement in distortion was reported. Mean effectiveness of correction was also reported by utilizing t test to compare dDT and dCT. The number of distortion traces with underlying lesions on optical coherence tomography was also analyzed. Results: Mean age of the subjects was 76.6 (±9.5) years. Each patient traced six reference lines and each was considered a separate case. Out of 30 cases, 17 (56.6%) elicited distortion. Mean percent improvement in distortion was 71.3 ± 23% ( p Conclusion: Software-generated corrections can potentially correct for perceived distortions in patients with age-related macular degeneration, especially in cases with preserved photoreceptor layer.

We explored visuomotor adaptation and spatial generalization of three-dimensional reaching movements performed in a virtual reality environment. We used a multiphase learning paradigm. First, subjects performed reaching movements to six targets without visual feedback (VF) (pre-exposure phase). Next, participants aimed at one target with veridical VF (baseline phase). Immediately after, they were required to adapt their movements to a triaxial visuomotor perturbation (horizontal, vertical, and sagittal translations) between actual hand motion and VF of hand motion in the virtual environment (learning phase). Finally, subjects aimed at the same targets as in the baseline (aftereffect) and pre-exposure phases (generalization) without VF (post-exposure phase). The results revealed spatial axis-dependent visuomotor adaptation capacities. First, subjects showed smaller intertrial variability along the horizontal compared to the sagittal and vertical axes during the baseline and learning phases. Second, although subjects were unaware of the visual distortion, they adapted their movements to each component of the triaxial perturbation. However, they showed reduced learning rate and less persistent adaptation (aftereffect) along the vertical than the horizontal and sagittal axes. Similarly, subjects transferred the newly learned visuomotor association to untrained regions of the workspace, but their average level of generalization was smaller along the vertical than the horizontal and sagittal axes. Collectively, our results suggest that adapting three-dimensional movements to a visual distortion involves distinct processes according to the specific sensorimotor integration demands of moving along each spatial axis. This finding supports the idea that the brain employs a modular decomposition strategy to simplify complex multidimensional visuomotor tasks.

Panoramic visual tracking has high application value in many situations, but its visual distortion is likely to cause low tracking robustness or loss of target. This paper presents a panoramic visual tracking method based on adaptive feature fusion method, the size of the trapezoidal frame is calibrated with target moving in the method, and the linear model of trapezoidal frame parameters is fitted, then according to the model trapezoidal area of target extracted, and are modified to target trapezoidal region through the affine transformation; Based on filter tracking framework, the fusion of color and shape information is as the main characteristics of the target tracking, and Bayesian fusion recursive formula is used for calculating the particle weights. The experimental results show that the proposed algorithm is better than the existing methods in tracking precision and anti occlusion, and effectively improves the robustness of panoramic visual tracking.

A 73-year-old woman presented with 3 years of monocular visual distortion and progressive binocular diplopia. She was found to have a comitant left hypertropia due to an epiretinal membrane causing inferior foveal drag. Displacement of the fovea from an epiretinal membrane is a likely under-recognized cause ocular cause of a comitant binocular diplopia.

Metamorphopsia is the visual misperception of the shape of objects. Retinal diseases, especially those affecting the macula, are responsible for the majority of cases. However, it can also be seen during migraine attacks, epileptic seizures and damage to visual pathways in the brain.Infarction in the splenium of the corpus callosum may cause visual agnosia, prosopometamorphopsia, alexia and amnesia. We describe here a case of isolated metamorphopsia caused by splenial infarction in the absence of any other neurological symptoms.

Recent advances of computerized graphical methods have received significant attention for detection and home monitoring of various visual distortions caused by macular disorders such as macular edema, central serous chorioretinopathy, and age-related macular degeneration. After a brief review of macular disorders and their conventional diagnostic methods, this paper reviews such graphical interface methods including computerized Amsler Grid, Preferential Hyperacuity Perimeter, and Three-dimensional Computer-automated Threshold Amsler Grid. Thereafter, the challenges of these computerized methods for accurate and rapid detection of macular disorders are discussed. The early detection and progress assessment of macular disorders can significantly enhance the required clinical procedure for the diagnosis and treatment of macular disorders.

Background: Visualizing one's own painful body part appears to have an effect on reported pain intensity. Furthermore, it seems that manipulating the size of the viewed image can determine the direction and extent of this phenomenon. When visual distortion has been applied to clinical populations, the analgesic effects have been in opposition to those observed in some experimental pain models. To help resolve this problem, we explored the effect of visualisation and magnification of the visual image on reported pain using a delayed onset muscle soreness (DOMS) pain model. Methods: We induced DOMS in the quadriceps of 20 healthy volunteers. Forty‐eight hours later, participants performed a series of painful contractions of the DOMS‐affected muscle under four randomised conditions: (1) Viewing the injured thigh; (2) Viewing the contralateral thigh; (3) Viewing a neutral object; and (4) Viewing the injured thigh through magnifying glasses. For each condition, participants rated their pain intensity during a series of painful contractions. Results: We observed that direct visualisation of the injured thigh had no effect on pain intensity when compared to viewing the contralateral thigh or neutral object. However, magnification of the DOMS‐affected leg during the performance of painful contractions caused participants to report more pain than when viewing the injured thigh normally. Conclusions: These results further demonstrate that the effect of visualisation varies between different pain conditions. These results may have implications for the integration of visual feedback into clinical practice. Significance: We present delayed onset muscle soreness as a model for exploring visually induced analgesia. Our findings suggest that this phenomenon is expressed differently in exogenous and endogenous experimental pain models. Further exploration may offer a potential pathway for the integration of visual analgesia into the management of clinical pain. Refereed/Peer-reviewed

Curve-section traffic accidents occur due to a mixture of vehicle, human, and road environmental factors. Traffic safety research in curve sections, however, so far has been confined to only investigating the effect of highway geometry factors on traffic accidents. Accordingly, this study suggested curved part safety-level evaluation criteria by complexly considering the hazard-level, which forecasts traffic accidents utilizing geometric structure of road, and the level of visual distortion, which recognizes the geometric structure of road as different from actual. The research first presents data collected on the geometry of highways in curve sections and from field investigations of traffic accidents. Second, a rating scale for curve-section safety level is presented with a consideration of hazard levels and visual distortion as variables. Third, evaluation criteria are presented for curve-section safety level, utilizing a safety-level rating scale. The evaluation criteria are classified into three levels dependent on route alignment type and each level is again classified into six grades from A to F. In this research, the causes of accidents can be determined in advance during design of the curve sections of a highway by applying evaluation criteria for the safety level as the curve sections are developed, and thus can be utilized in selecting a priority order for projects when implementing improvements in existing roads.

In this work, a novel bit allocation method based on visual attention and distortion sensitivity is developed for JPEG2000. Although, visual attention map for an image can be measured by using well-known saliency map methods, true visual attention map can be obtained by conducting experiments to determine fixation points and their durations. A perception model might turn these duration of fixations into visual attention levels. Besides visual attention, visual distortion sensitivity may guide the bit allocation process effectively. This is because human visual system is more sensitive to the distortion around the edges than the distortion in the complex textured areas. In this work, a novel visual distortion sensitivity method that considers all edges without using a threshold for gradient magnitude and uses local entropy of gradient orientation distribution is proposed. Thus, the visual attention and the distortion sensitivity level of each code-block determine its quantization parameters. Using bit allocation based on the visual attention map provides higher subjective evaluation score than using bit allocation based on the post compression rate-distortion optimization method or on a previously proposed method based on the saliency map. Secondly, it is shown that the use of visual distortion sensitivity allows higher objective evaluation scores to be attained.

The feeling of owning and controlling the body relies on the integration and interpretation of sensory input from multiple sources with respect to existing representations of the bodily self. Illusion paradigms involving multisensory manipulations have demonstrated that while the senses of ownership and agency are strongly related, these two components of bodily experience may be dissociable and differentially affected by alterations to sensory input. Importantly, however, much of the current literature has focused on the application of sensory manipulations to external objects or virtual representations of the self that are visually incongruent with the viewer’s own body and which are not part of the existing body representation. The current experiment used MIRAGE-mediated reality to investigate how manipulating the visual, spatial and temporal properties of the participant’s own hand (as opposed to a fake/virtual limb) affected embodiment and action. Participants viewed two representations of their right hand inside a MIRAGE multisensory illusions box with opposing visual (normal or grossly distorted), temporal (synchronous or asynchronous) and spatial (precise real location or false location) manipulations applied to each hand. Subjective experiences of ownership and agency towards each hand were measured alongside an objective measure of perceived hand location using a pointing task. The subjective sense of agency was always anchored to the synchronous hand, regardless of physical appearance and location. Subjective ownership also moved with the synchronous hand, except when both the location and appearance of the synchronous limb were incongruent with that of the real limb. Objective pointing measures displayed a similar pattern, however movement synchrony was not sufficient to drive a complete shift in perceived hand location, indicating a greater reliance on the spatial location of the real hand. The results suggest that while the congruence of self-generated movement is a sufficient driver for the sense of agency, the sense of ownership is additionally sensitive to cues about the visual appearance and spatial location of one’s own body.

This paper presents a new mathematical model along with a measurement platform for accurate detection and monitoring of various visual distortions (VD) caused by macular disorders such as central serous chorioretinopathy (CSR) and age-related macular degeneration (AMD). This platform projects a series of graphical patterns on the patient&rsquo, s retina and calculates the severity of VDs accordingly. The accuracy of this technique relies on the accurate detection of distorted lines by the patient. We also propose a simple mathematical model to evaluate the VD created by CSR. The model is used as a control for the test results achieved from the proposed platform. The proposed platform consists of the required hardware and software for the generation and projection of patterns along with the collection and processing of patients against their standard optical coherence tomography (OCT) images. Based on these results, the OCT images agree with the VD test results, and the proposed platform can be used as an alternative home monitoring method for various macular disorders.

Image retargeting algorithms attempt to adapt the image content to the screen without distorting the important objects in the scene. Existing methods address retargeting of a single image. In this paper, we propose a novel method for retargeting a pair of stereo images. Naively retargeting each image independently will distort the geometric structure and hence will impair the perception of the 3D structure of the scene. We show how to extend a single image seam carving to work on a pair of images. Our method minimizes the visual distortion in each of the images as well as the depth distortion. A key property of the proposed method is that it takes into account the visibility relations between pixels in the image pair (occluded and occluding pixels). As a result, our method guarantees, as we formally prove, that the retargeted pair is geometrically consistent with a feasible 3D scene, similar to the original one. Hence, the retargeted stereo pair can be viewed on a stereoscopic display or further processed by any computer vision algorithm. We demonstrate our method on a number of challenging indoor and outdoor stereo images.

Aim: With this case study, we hypothesize that identical concomitant symptoms exist between ASDs and Meares-Irlen Syndrome, determined by the level of visual stress. Method: A questionnaire was given to subjectively identify the type and degree of symptoms associated with visual perception, and if these symptoms disrupted quality of life and learning process. This questionnaire was composed of questions on visual symptoms such as: symptoms linked to near and far visual distortion, binocular visual dysfunction and reading or writing errors experienced by the patient. Results: This patient experienced a significant reduction in visual stress symptoms when wearing color-tinted lenses (p

International audience; Immersion is the subjective impression of being deeply involved in a specific situation, and can be sensory or cognitive. In this position paper, we use a basic model of visual perception to study how ultra-high resolution wall displays can provide visual immersion. With their large size, depending on the position of viewers in front of them, wall displays can provide a surrounding and vivid environment. Users close to the wall can have their visual field filled by the wall and they are able to see clearly a large amount information with a fine resolution. However, when close to the wall, visual distortion due to large possible viewing angles, can affect the viewing of data. On the contrary, from far away, distortion is no longer an issue, but the viewers' visual field is not fully contained inside the wall, and the information details seen are less fine.

A 68-year-old man with diabetes mellitus type 2 presented himself with visual distortion and apraxia. Nonketotic hyperglycemic seizure with both motor and sensory components was suspected. Tc-ECD perfusion SPECT demonstrated hyperperfusion at right parieto-occipital lobe during ictal phase. Normalization of hyperperfused area was noted on follow-up perfusion SPECT after intense glucose control. In nonketotic hyperglycemic state, the depletion of GABA in cerebral neurons lowers the seizure threshold. We demonstrated that ictal phase perfusion SPECT contributed to not only diagnosis but also served as a follow-up tool.

Motion sickness is caused by the information differences between the vestibular, visual, and bodily senses. Window curvature and sight blurring are considered to influence eyesight information. This study experimentally investigated the influence of motion sickness by window curvature and sight blurring changes in the response to multiple combinations of conditions. The result indicated that a view from a car window with a vertical wave on the window surface was likely to cause motion sickness. Conversely, visual distortion in the horizontal direction could be acceptable to passengers. The study also proposed the minimum design requirements for car-body shape based on the results.

Presbyopia, the gradual loss of accommodation that becomes clinically significant during the fifth decade of life, is a physiologic inevitability. Different technologies are being pursued to achieve surgical correction of this disability; however, a number of limitations have prevented widespread acceptance of surgical presbyopia correction, such as optical and visual distortion, induced corneal ectasia, haze, anisometropy with monovision, regression of effect, decline in uncorrected distance vision, and the inherent risks with invasive techniques, limiting the development of an ideal solution. The correction of the presbyopia and the restoration of accommodation are considered the final frontier of refractive surgery. The purpose of this paper is to provide an update about current procedures available for presbyopia correction, their advantages, and disadvantages.

An account of intersensory integration is premised on knowing that different sensory inputs arise from the same object. Could, however, the combination of the inputs be impaired although the “unity assumption” holds? Forty observers viewed a square through a minifying (50%) lens while they simultaneously touched the square. Half could see and half could not see their haptic explorations of the square. Both groups, however, had reason to believe that they were touching and viewing the same square. Subsequent matches of the inspected square were mutually biased by touch and vision when the exploratory movements were visible. However, the matches were biased in the direction of the square’s haptic size when observers could not see their exploratory movements. This impaired integration without the visible haptic explorations suggests that the unity assumption alone is not enough to promote intersensory integration.

If proprioceptive feedback is degraded by agonist-antagonist muscle vibration, then adaptation to rotated vision remains intact while adaptation to a velocity-dependent force field worsens. Here we evaluate whether this differential effect of vibration is related to the physical nature of the distortion - visual versus mechanical - or to their kinematic coupling to the subjects' hand - velocity versus position dependent. Subjects adapted to a velocity-dependent visual distortion, to a position-dependent force, or to a velocity-dependent force; one half of the subjects adapted with, and the other half without agonist-antagonist vibration at the wrist, elbow, and shoulder. We found, as before, that vibration slowed down adaptation to a velocity-dependent force. However, vibration did not modify adaptation to the other two distortions, nor did it influence the aftereffects of any distortion. From this we conclude that intact proprioception supports strategic compensatory processes when proprioceptive signals agree with visual ones, and provide relevant (dynamic) information not available to the visual system.

To evaluate the determinants of patient satisfaction with photodynamic therapy (PDT) for neovascular age-related macular degeneration (AMD) or polypoidal choroidal vasculopathy (PCV).Questionnaires were mailed to 69 patients who had undergone PDT for AMD or PCV at the Kobe City General Hospital. The questionnaire considered the following parameters: subjective change in visual acuity, subjective change in the relative scotoma in central vision, subjective change in visual distortion, and patient satisfaction with PDT scored on a 100-point scale.Nine patients (14%) reported their subjective visual acuity change as "significantly improved" and 21 (32%) as "slightly improved"; 18 (27%) reported "no change"; 12 (18%) reported their visual acuity as "slightly worsened"; and 6 (9%) as "significantly worsened." Subjective change in the central scotoma was reported improved in 43 patients (64%) and visual distortion had improved subjectively in 31 patients (47%). The satisfaction score was 59 +/- 25 in patients who had undergone PDT for AMD and 75 +/- 24 in those with PCV. Not only the visual acuity change but also the subjective change in central scotoma and visual distortion correlated significantly with the satisfaction score.More patients who have undergone PDT for AMD or PCV perceive improvement in central scotoma and visual distortion than in visual acuity. Since these subjective changes correlated significantly with the satisfaction score, subjective change in central scotoma and visual distortion, in addition to visual acuity, should be taken into account in evaluating the benefits of PDT.

This study investigated the benefits of a curved display compared to a flat display and proposed the optimal radius of curvature for a monitor. The study was carried out in two steps. For identifying the optimal radius, a bendable monitor prototype was used to enable subjects to adjust the display radius manually. Each subject was instructed to search for an optimal radius according to individual preference and visual comfort. Six different themes were applied for the display content. The subjects also reported the radius in which a visual distortion occurred. As a result, it was found that curvature with a radius equal to 600 mm to 700 mm is optimal for a 23-inch diagonal display, while 700 mm to 800 mm is appropriate for a 27-inch diagonal display. Moreover, when the radius of curvature was smaller than 600 mm, a majority reported distortion regardless of the display size. Next, a validation test confirmed that the subjects read the texts faster on the curved display than on the flat display. Based on the empirical results of two experiments, the excellence of a curved monitor in terms of visual comfort, preference, and immersion was verified.

Choroidal osteoma is a rare benign intraocular tumor composed of calcification throughout the choroid. Various treatment modalities are available according to location of the tumor and the cause of the visual distortion. We report herein a 30-year-old male who was referred to our hospital with acute blurred vision as a result of the subretinal hemorrhage from choroidal osteoma. We ruled out the presence of CNV and observation was preferred and we prevented unnecessary treatment attempts as spontaneous recovery is the easiest and safest way.

Retyping attacks intent to interpret the content of a digital document and rewrite it as a new document with the aim of removing possible watermarks inserted in the document. These attacks can be automated using Object Character Recognition software making possible to attack a big volume of digital documents handled in organizational environments. Previous works have studied the robustness of watermarked text-based digital documents to retyping attacks, using a syntactic and semantic approach. However, little attention has been put on watermarking of image-based digital documents, which have resulted to be totally vulnerable to retyping attacks. This paper presents a study of the robustness of fingerprinted image-based digital documents against automated retyping attacks using a state-of-the-art fingerprinting system. Robustness is achieved by inserting fingerprints/watermarks in the frequential components of the digital documents causing visual distortion on the fingerprinted documents, which makes that when a retyping attack be applied over it, the extracted text be useless. From the experiments in this study, it was found that the evaluated system resists automated retyping attacks generating an information loss above 50% for most of the fingerprinted documents in lossless and lossy formats. Additionally, it was found that exists a tradeoff between the robustness of fingerprinted image-based digital documents to retyping attacks and the robustness to other common attack in fingerprinted documents, the collusion attack.

Recent work has shown that preplanned motor programs can be rapidly released via fast conducting pathways using a startling acoustic stimulus (SAS). Our question is whether the startle-elicited response might also release a recently learned internal model, which draws on experience to predict and compensate for expected perturbations in a feedforward manner. Our initial investigation using adaptation to robotically produced forces showed some evidence of this, but the results were potentially confounded by co-contraction caused by startle. In this study, we eliminate this confound by asking subjects to make reaching movements in the presence of a visual distortion. Results show that a startle stimulus (1) decreased performance of the recently learned task, and (2) reduced after-effect magnitude. Since the recall of learned control was reduced, but not eliminated during startle trials, we suggest that multiple neural centers (cortical and subcortical) are involved in such learning and adaptation. These findings have implications for motor training in areas such as piloting, teleoperation, sports, and rehabilitation.

Objective: The present experiment evaluated whether training involving throwing transferred to metric distance estimation (i.e., describing in feet and inches the distance between oneself and targets). Background: In prior work, we found that metric estimation training negatively transferred to throwing. We explained our results in terms of cognitive intrusion. The present study tested that possibility by swapping our training and transfer tasks. Method: During pretesting, participants verbally estimated the metric distances between themselves and targets, or they threw a beanbag to targets. During training, participants donned goggles that distorted their vision. While wearing the goggles, they threw a beanbag to targets. Half received feedback. During posttesting, participants removed the distorting goggles and completed the same task that they performed during pretesting. Results: The results indicated that the distorting goggles degraded throwing at the beginning of training, visual feedback improved throwing during training, the effects of training with feedback persisted into the throwing posttest, and the effects of training with feedback did not transfer to the verbal metric estimation posttest. Conclusion: Training involving throwing was effective, but did not transfer to verbal metric distance estimation. This supports our argument that the negative transfer observed in our previous study stemmed from cognitive intrusion. Application: The present experiment suggests that the creation of distance estimation training should begin with a careful analysis of the transfer task, and that distance estimation training programs should explicitly teach trainees that their training will not generalize to all distance estimation tasks.

Systemic lupus erythematosus (SLE) associated with antiphospholipid syndrome can have ocular complications. We report a 44-year-old Chinese lady with recurrent relapses of SLE and antiphospholipid syndrome with high disease activity, presenting with visual distortion in her right eye for 2 months. There was subretinal hemorrhage in her right eye, confirmed on investigations to be choroidal neovascularization secondary to a variant of age-related macular degeneration known as polypoidal choroidal vasculopathy (PCV). Anti-vascular endothelial growth factor therapy resolved her eye condition. SLE could be associated with PCV via common mechanisms, including complement pathway activation and vasculitis involving the choroidal circulation.

We report a 47-year-old right-handed woman with simple partial seizures manifesting in part as an urge to defecate shortly after a visual distortion. On at least one occasion, this was followed by head deviation to the left and a secondarily generalized tonic-clonic seizure. The ictal electroencephalogram lateralized to the right hemisphere, suggesting that the ictal urge to defecate may lateralize to this side.

Retinal Prosthesis device has been approved by FDA for treatment of vision impairment caused by RP. Validating the visual distortion estimation algorithms used in prosthesis is crucial for the safe use of prosthesis. An approach based on metamorphic testing was described to validate a prosthesis distortion estimation algorithm. Four metamorphic relations including two necessary conditions for the correct functioning of the estimation algorithm were identified. Violations in two metamorphic relations were detected showing different estimation behavior of prosthetic vs. regular images and those having high distortions.

DF is a 56-year-old man who complained of slight visual distortion in his right eye on presentation to his optometrist. Examination showed visual acuity of 20/20-2 in that eye and 20/20 in his left eye. The anterior segment examination was normal, but fundus examination showed a lightly pigmented submacular lesion. Fluorescein angiography was ordered, and the lesion demonstrated initial hypofluorescence with delayed spotty leakage and staining. Echography was performed and displayed a high-reflective lesion measuring 1.11 mm in thickness and just under 5 mm in basal diameter. The patient was seen a year later with no change in symptoms or echographic findings.

TA is a 52-year-old man who complained of some visual distortion in his right field of vision for several weeks. He was seen by an ophthalmologist who documented visual acuity of 20/30-2 OD and 20/20 OS. Ophthalmoscopic examination found a yellow-orange elevated lesion just below the macula. Fluorescein angiography was performed and demonstrated mottled leakage of dye within the lesion that increased over several minutes. These findings were consistent with a choroidal hemangioma, but an amelanotic melanoma or metastatic tumor could not be eliminated completely.

Image retargeting aims to avoid visual distortion while retaining important image content in resizing. However, current image retargeting methods usually fail in difficult situations, such as complex structures and intricate arrangements of objects. In this paper, we propose a novel image retargeting approach, which provides low visual distortion retargeting results by combining region warping and occlusion. We first represent image region with occlusion probability to avoid inaccuracy in image decomposition. Then we combine region warping and occlusion in a unified framework, and transform it to a pixel-level retargeting problem. To verify the performance of our approach, we implement it with two operators, seam carving and pixel warping. Experiments demonstrate the effectiveness of the proposed approach.

This paper presents a novel model for the removal of semi-transparent blotches on the digitized copy of sepia archive photographs. As these defects cannot be successfully eliminated by conventional interpolation methods, a proper combination of a novel visual distortion and multiresolution analysis is used for performing user-independent detection and restoration. Extensive experimental results and comparative studies show the potential of the proposed model in terms of visual quality and computational complexity.

Coloured filters have been found to reduce visual distortion of text in children with autism spectrum disorders (ASD). We investigated the effect of the overlays on the “mind in the eye” task in children with ASD and controls matched for age, gender, and nonverbal IQ. Children were shown photographs of the periocular region of various faces and were asked to judge which emotion was being expressed in the eyes. In children with ASD, the perception of the emotion was significantly improved when the photograph was covered by a coloured overlay. The improvement was significantly greater than in the controls, who showed no significant effect of the overlay. A perceptual impairment may contribute to the social difficulties shown in ASD.

Rate-distortion optimization (RDO) plays a significant role in video coding. However, in most RDO methods, the distortion measurement metrics consider only the spatial distortion of statistical pixel errors. People have concerns about not only the information of independent pixels, but also the spatial and temporal correlations between them. In order to make the distortion assessment more consistent with human perception, temporal information of the successive images and the characteristics of human visual perception should be considered as well. In this paper, we propose a rate-distortion model based on spatio-temporal video structural similarity (stVSSIM) index, which takes both spatial and temporal visual quality into account. Meanwhile, to obtain a reasonable trade-off between bit-rate and visual quality dynamically, a perceptual adaptive Lagrange multiplier selection method is presented. Simulation results show that the proposed method averagely reduces 20% bit-rate under the equal visual quality and the adaptive Lagrange multiplier can further improve the results.

BACKGROUND: Radial suturing of 6.5-millimeter scleral tunnel incisions following cataract surgery can create significant with-the-rule astigmatism in the immediate postoperative period. Because of the significant visual distortion and slow visual recovery seen with radial suturing, this study was undertaken to compare two other suturing techniques which induce lesser amounts of with-the-rule astigmatism in the immediate postoperative period. METHODS: The refractive behavior of eyes closed with loose radial sutures and with horizontal sutures was compared to the behavior of eyes closed with the more traditional "tight" radial sutures following phacoemulsification surgery. RESULTS: Eyes sutured with loosely tied radial sutures demonstrated minimal with-the-rule cylinder immediately following surgery (1.25 D) and showed a more rapid stabilization of astigmatism than did the eyes tied with tight radial sutures, 2 months versus up to 6 months. However, the eyes tied with horizontal sutures, which showed no induced with-the-rule astigmatism at the time of surgery, showed even more rapid stabilization between 5 days and 1 month from the time of surgery. CONCLUSION: To get the most rapid visual rehabilitation following cataract surgery, a wound closure which generates no induced with-the-rule cylinder such as horizontal sutures would be required. [J Refract Corneal Surg. 1994;10:339-342.] RESUME INTRODUCTION: Il a été démontré que les sutures radiaires des incisions sclerale en tunnel après la chirurgie de cataracte induisent un astigmatisme significatif qui se conforme à la règle dans la période post-opératoire immédiate. A cause de la distorsion visuelle et de la lente récupération de vision qui vont avec des incisions fermés ainsi, on a étudié deux autres méthodes de suture des incisions après l'extraction de cataracte. METHODES: Les propriétés réfractives des yeux fermés avec des sutures radiaires lâches et avec des sutures horizontales furent comparées avec celles des yeux fermés avec les sutures radiaires secures traditionelles après la phaco-émulsification. RÉSULTATS: Les yeux fermés avec des sutures radiaires et lâches ont démontré très peu d'astigmatisme se conformant à la règle immédiatement après la chirurgie (1,25 D) et ont démontré une stabilisation rapide d'astigmatisme (2 mois) par comparaison avec les yeux suturés sécurement et radiairement (6 mois). Cependant, les yeux fermés avec les sutures horizontales, qui n'ont pas démontré l'induction d'astigmatisme se conformant à la règle, se sont stabilisés le plus rapidement, entre 5 et 30 jours post-opérativement. CONCLUSION: La guérison visuelle après la chirurgie de cataracte est plus rapide dans le cas des fermetures qui n'entrainent pas d'astigmatisme, comme il semble avec les sutures horizontales. (Translated by Rob Mack, MD, Iowa City, Iowa.) SOMMARIO PREMESSA: E'stato già dimostrato che la sutura radiale delle incisioni a tunnel sclerale dopo chirurgia della cataratta può provocare un significativo astigmatismo secondo regola nell'immediato periodo postoperatorio, che determina una significativa distorsione visiva e un lento recupero visivo osservato con le suture radiali. Questo studio è stato fatto allo scopo di comparare due altre tecniche di sutura che inducono minore astigmatismo secondo regola nell'immediato periodo postoperatorio. METODI: ? comportamento refrattivo degli occhi suturati con sutura radiale allentata e con sutura orizzontale è stato paragonato al comportamento di occhi suturati con la più tradizionale sutura serrata radiale dopo facoemulsificazione.

PURPOSE To present a simple mathematical eye model capable of modeling the metamorphopsia (visual distortion) reported by patients with central serous retinopathy (CSR). METHODS A computer program was developed to perform the modeling. A simple wide-angle eye model was adapted to include a spherical edema added at the retina. The visual impression was taken as the projection of the retinal pattern back into object space, after the edema had been deflated to its undistorted state. The deflation of the edema was facilitated by assuming a simplified "spreading of photoreceptors" rule. Numerical examples have been included to demonstrate the use of the model. In particular, an Amsler grid was projected to the retina with CSR, to illustrate the associated geometrical distortion. RESULTS The eye model predicted a pincushion-like distortion of an Amsler grid, that depended (for given height) on the radius of curvature of the CSR. A larger radius of curvature resulted in less pincushion distortion extending over a larger area. CONCLUSIONS An eye model has been developed that simulates distortion because of CSR. The predicted visual impression of a spherical edema is a pincushion-like distortion. This model may have applications in benchmarking alternate chart designs for detecting CSR, investigating optical aberrations over the edema as well as simulating the visual effect of metamorphopsia in other retinal conditions.

This paper discusses the use of documentary films and photographs of Aboriginal people from the Ngaanyatjarra region of Western Australia in the late 1950s during a heated public debate about remote Aboriginal health and welfare. The recruitment of images of people in situations of physical distress to illustrate arguments about political and bureaucratic neglect was controversial, sparking accusations of propaganda and disagreement about the norms of Aboriginal well-being. Some of the images produced, most notably those of Western Australian politician William Grayden, had a significant impact on audiences at the time. Grayden's film, shown in a Perth cinema under the title 'Their Darkest Hour' and sometimes referred to as Manslaughter, is celebrated in recent histories of Aboriginal activism and extracts from it have been used by a new generation of activist filmmakers and artists. The perspectives of the Aboriginal people who appear in Grayden's images are, however, a notable absence in these accounts. When considered alongside other historical sources, local Aboriginal voices reveal a significant visual distortion of the quality of people's lives and the substance of their histories as they are remembered today.

The only sure diagnostic indicator of Glaucoma is the intra ocular pressure (IOP). When the IOP increases to about 2 times the normal average pressure of 16 mmHg (2.1kPa) the pressure in the eyeball affects the optic nerve and causes visual distortion and, ultimately, can cause blindness.

An improved reversible data hiding scheme, which can restore the original image completely after data extraction, is presented in this paper. The method is an extended subsampling reversible data hiding method. Compared with the previous method, the proposed method has much more room for data hiding. The data hiding capacity is much higher than the previous method while the visual distortion keep the same as the previous method. Experimental results show that the proposed algorithm provides high embedding capacity while keeping the distortions low

The combination of intra prediction, transform, and quantization in the H.264/AVC video coding standard offers high compression performance in picture areas where inter prediction is unavailable or fails. Motivated from coding experiments with the reference software that resulted in significant visual distortion with certain types of content, we investigated intra prediction further. Intra prediction may propagate distortion to subsequent blocks or macroblocks. As a result, rate-distortion optimized mode decision needs to account for this distortion. Furthermore, rounding operations in H.264/AVC accumulate small but non-trivial errors. This is especially true for the encoding process of the 16 times 16 intra prediction mode, which involves a combination of DCT and Hadamard transforms. We investigate, theoretically and experimentally, the problem of visual distortion caused by sub-optimal intra prediction coding decisions by modeling distortion propagation across subsequent blocks. We propose two algorithms that address the problem.

The quality layers concept is proposed and adopted in the JSVM in order to ensure an optimal adaptation in a rate-distortion sense. In this paper it is extended to multiview case for scalable coding of stereo videos. Rate-visual-distortion optimized rate allocation among the views is necessary for efficient transport of 3DTV data over the Internet. This paper addresses a standard compatible approach to solve the problem. Experimental results are presented that demonstrate the effectiveness of the proposed method for several stereo videos.

We consider the problem of constructing visually optimized balanced multiple descriptions of images, instead of being op- timized with the conventional measure of mean squared error (MSE). The recently proposed Modified Multiple Description Scalar Quantizer (MMDSQ) is used because its central and side quantizers all have convex and uniform cells. Since the majority of research results on the visual distortion caused by quantization noise assumes convex and uniform quantizer cells, they can be conveniently applied to the system based on MMDSQ. The technique provides substantially higher side reconstruction perceived quality when compared at the same central reconstruction quality, which is verified through per- ceptual tests.