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Disorders that specifically affect central and peripheral vision constitute invaluable models to study how the human brain adapts to visual deafferentation. We explored cortical changes after the loss of central or peripheral vision. Cortical thickness (CoTks) and resting-state cortical entropy (rs-CoEn), as a surrogate for neural and synaptic complexity, were extracted in 12 Stargardt macular dystrophy, 12 retinitis pigmentosa (tunnel vision stage), and 14 normally sighted subjects. When compared to controls, both groups with visual loss exhibited decreased CoTks in dorsal area V3d. Peripheral visual field loss also showed a specific CoTks decrease in early visual cortex and ventral area V4, while central visual field loss in dorsal area V3A. Only central visual field loss exhibited increased CoEn in LO-2 area and FG1. Current results revealed biomarkers of brain plasticity within the dorsal and the ventral visual streams following central and peripheral visual field defects. Electronic supplementary material The online version of this article (10.1007/s00429-018-1700-7) contains supplementary material, which is available to authorized users.

Chordoid glioma of the third ventricle (CGTV) is a rare, slow-growing, World Health Organization Grade II glial tumor, with stereotyped localization in the anterior third ventricle. Despite being considered a noninvasive tumor, CGTV is usually associated with a poor clinical outcome due to its close proximity to important cerebral structures, such as the hypothalamus and visual pathways. Our patient with CGTV experienced visual involvement, but after subtotal surgical resection showed no evidence of progression at 5-year follow-up.

Emerging evidence suggests that white matter plasticity in the adult brain is preserved after sensory and behavioral modifications. However, little is known about the progression of structural changes during the process of decline in visual input. Here we studied two groups of patients suffering from advanced retinitis pigmentosa with specific deterioration of the visual field: patients who had lost their peripheral visual field, retaining only central (“tunnel”) vision, and blind patients with complete visual field loss. Testing of these homogeneous groups made it possible to assess the extent to which the white matter is affected by loss of partial visual input and whether partially preserved visual input suffices to sustain stability in tracts beyond the primary visual system. Our results showed gradual changes in diffusivity that are indicative of degenerative processes in the primary visual pathway comprising the optic tract and the optic radiation. Interestingly, changes were also found in tracts of the ventral stream and the corticospinal fasciculus, depicting a gradual reorganisation of these tracts consequentially to the gradual loss of visual field coverage (from intact perception to partial vision to complete blindness). This reorganisation may point to microstructural plasticity underlying adaptive behavior and cross-modal integration after partial visual deprivation.

Behavioral alterations emerging after central or peripheral vision loss suggest that cerebral reorganization occurs for both the afferented and deafferented early visual cortex (EVC). We explored the functional reorganization of the central and peripheral EVC following visual field defects specifically affecting central or peripheral vision. Compared to normally sighted, afferented central and peripheral EVC enhance their functional connectivity with areas involved in visual processing, whereas deafferented central and peripheral EVC increase their functional connectivity with more remote regions. The connectivity pattern of afferented EVC suggests adaptive changes that might enhance the visual processing capacity whereas the connectivity pattern of deafferented EVC may reflect the involvement of these regions in high-order mechanisms. Characterizing and understanding the plastic changes induced by these visual defects is essential for any attempt to develop efficient rehabilitation strategies.

International audience; In the congenitally blind, language processing involves visual areas. In the case of normal visual development however, it remains unclear whether later visual loss induces interactions between the language and visual areas. This study compared the resting-state functional connectivity (FC) of retinotopic and language areas in two unique groups of late visually deprived subjects: (1) blind individuals suffering from retinitis pigmentosa (RP), (2) RP subjects without a visual periphery but with preserved central “tunnel vision”, both of whom were contrasted with sighted controls. The results showed increased FC between Broca's area and the visually deprived areas in the peripheral V1 for individuals with tunnel vision, and both the peripheral and central V1 for blind individuals. These findings suggest that FC can develop in the adult brain between the visual and language systems in the completely and partially blind. These changes start in the deprived areas and increase in size (involving both foveal and peripheral V1) and strength (from negative to positive FC) as the disease and sensory deprivation progress. These observations support the claim that functional connectivity between remote systems that perform completely different tasks can change in the adult brain in cases of total and even partial visual deprivation.

Purpose The Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc, Sylmar, CA) was developed to restore some vision to patients blind as a result of retinitis pigmentosa (RP) or outer retinal degeneration. A clinical trial was initiated in 2006 to study the long-term safety and efficacy of the Argus II System in patients with bare or no light perception resulting from end-stage RP. Design Prospective, multicenter, single-arm clinical trial. Within-patient controls included the nonimplanted fellow eye and patients’ native residual vision compared with their vision with the Argus II. Participants Thirty participants in 10 centers in the United States and Europe. Methods The worse-seeing eye of blind patients was implanted with the Argus II. Patients wore glasses mounted with a small camera and a video processor that converted images into stimulation patterns sent to the electrode array on the retina. Main Outcome Measures The primary outcome measures were safety (the number, seriousness, and relatedness of adverse events) and visual function, as measured by 3 computer-based, objective tests. Secondary measures included functional vision performance on objectively scored real-world tasks. Results Twenty-four of 30 patients remained implanted with functioning Argus II Systems at 5 years after implantation. Only 1 additional serious adverse event was experienced after the 3-year time point. Patients performed significantly better with the Argus II on than off on all visual function tests and functional vision tasks. Conclusions The 5-year results of the Argus II trial support the long-term safety profile and benefit of the Argus II System for patients blind as a result of RP. The Argus II is the first and only retinal implant to have market approval in the European Economic Area, the United States, and Canada. © 2016 American Academy of Ophthalmology

Background: Use of the antiepileptic drug vigabatrin is associated with an elevated risk of visual field loss. Objective: To determine the frequency of, and risk factors for, vigabatrin-attributed visual field loss (VAVFL) in the setting of a large-scale, multinational, prospective, observational study. Study design: A comparative, open-label, parallel-group, multicentre study. Setting: Hospital outpatient clinics at 46 centres in five countries. Patients: 734 patients with refractory partial epilepsy, divided into three groups and stratified by age (8–12 years; >12 years) and exposure to vigabatrin. Group I comprised patients treated with vigabatrin for ≥6 months. Group II comprised patients previously treated with vigabatrin for ≥6 months who had withdrawn from the drug for ≥6 months. Group III comprised patients never treated with vigabatrin. Patients underwent perimetry at either 4- or 6-month intervals, for up to 36 months. Visual field outcome was evaluated masked to drug exposure. Intervention: Perimetry. Main outcome measure: The visual field outcome at each of four analysis points: (i) at enrolment (i.e. baseline, all patients); (ii) for patients exhibiting a conclusive outcome at the initial visual field examination; (iii) for patients exhibiting at least one conclusive outcome to the visual field examinations; and (iv) at the last conclusive outcome to the visual field examinations. Results: Of the 734 patients, 524 yielded one or more conclusive visual field examinations. For Group I, the frequency of VAVFL at the last conclusive examination was 10/38 (26.3%) for those aged 8–12 years and 65/150 (43.3%) for those aged >12 years. For Group II, the respective frequencies were 7/47 (14.9%) and 37/151 (24.5%). One case resembling VAVFL was present amongst the 186 patients in Group III at the last conclusive examination. The frequency of VAVFL in Groups I and II combined was 20.0% for those aged 8–12 years and 33.9% for those aged >12 years. VAVFL was associated with duration of vigabatrin therapy (odds ratio [OR] up to 15.2; 95% CI 4.4, 51.7), mean daily dose of vigabatrin (OR up to 26.4; 95% CI 2.4, 291.7) and male gender (OR 2.51; 95% CI 1.5, 4.1). VAVFL was more frequently detected with static than with kinetic perimetry (OR up to 0.43; 95% CI 0.24, 0.75). Conclusions: Since the probability of VAVFL is positively associated with treatment duration, careful assessment of the risk-benefit ratio of continuing treatment with vigabatrin is recommended in patients currently receiving this drug. All patients continuing to receive vigabatrin should undergo visual field examination at least every 6 months for the duration of treatment. We recommend two-level (three-zone), gradient-adapted, suprathreshold static perimetry of the peripheral field together with threshold perimetry of the central field out to 30° from fixation. The frequency of ophthalmological and perimetric examinations should be increased in the presence of VAVFL.

The exquisite sensitivity of the human visual system to form-from-motion (FfM) cues is well documented. However, identifying the neural correlates of this sensitivity has proven difficult, particularly determining the respective contributions of different motion areas in extrastriate visual cortex. Here we measured visual FfM perception and more elementary visual motion (VM) perception in a group of 32 patients suffering from acute posterior brain damage, and performed MRI-based lesion analysis. Our results suggest that severe FfM perception deficits without an associated deficit of VM perception are due to damage to ventral occipito-temporal cortex (VOT), whereas associated deficits of FfM and VM perception are due to damage either in proximity to area MT+/V5 or an area including lateral occipital complex (LOC) and VOT. These data suggest the existence of at least three functionally and anatomically distinct regions in human visual cortex that process FfM signals.

© 2015 American Academy of Ophthalmology. Purpose Retinitis pigmentosa (RP) is a group of inherited retinal degenerations leading to blindness due to photoreceptor loss. Retinitis pigmentosa is a rare disease, affecting only approximately 100 000 people in the United States. There is no cure and no approved medical therapy to slow or reverse RP. The purpose of this clinical trial was to evaluate the safety, reliability, and benefit of the Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc, Sylmar, CA) in restoring some visual function to subjects completely blind from RP. We report clinical trial results at 1 and 3 years after implantation. Design The study is a multicenter, single-arm, prospective clinical trial. Participants There were 30 subjects in 10 centers in the United States and Europe. Subjects served as their own controls, that is, implanted eye versus fellow eye, and system on versus system off (native residual vision). Methods The Argus II System was implanted on and in a single eye (typically the worse-seeing eye) of blind subjects. Subjects wore glasses mounted with a small camera and a video processor that converted images into stimulation patterns sent to the electrode array on the retina. Main Outcome Measures The primary outcome measures were safety (the number, seriousness, and relatedness of adverse events) and visual function, as measured by 3 computer-based, objective tests. Results A total of 29 of 30 subjects had functioning Argus II Systems implants 3 years after implantation. Eleven subjects experienced a total of 23 serious device- or surgery-related adverse events. All were treated with standard ophthalmic care. As a group, subjects performed significantly better with the system on than off on all visual function tests and functional vision assessments. Conclusions The 3-year results of the Argus II trial support the long-term safety profile and benefit of the Argus II System for patients blind from RP. Earlier results from this trial were used to gain approval of the Argus II by the Food and Drug Administration and a CE mark in Europe. The Argus II System is the first and only retinal implant to have both approvals.

Motion blindness (MB) is defined as the selective disturbance of visual motion perception despite intact perception of other features of the visual scene. MB is characterized by a pandirectional deficit of motion direction discrimination and is assumed to result from damage to the visual motion pathway, especially area MT/V5. However, the most characteristic feature of primate MT/V5 neurons is not their motion selectivity but their preference for one direction of motion (direction selectivity), which changes incrementally at neighbouring columns. In addition to this microscopic directional organization, studies in nonhuman and human primates suggest that single directions of motion are also coded at a more macroscopic level. We thus hypothesized that if MB in humans results from damage to direction-selective neurons in the visual motion pathway, posterior brain damage might cause MB which is direction selective, not pandirectional. The present study investigated motion direction discrimination in patients with posterior unilateral brain damage and determined separate psychophysical thresholds for the four cardinal directions. In addition, we analysed whether the direction of erroneous motion perception (i.e. the perception of right motion for upward motion) was random or showed a directional bias. We report three principal findings. First, motion direction discrimination was severely impaired in one or two directions while it was normal in the other directions. This constituted direction-selective MB. Second, MB was characterized not only by a quantitative direction-selective increase in psychophysical thresholds but also by a qualitative impairment of perceiving motion direction systematically in wrong directions. Both findings suggest that the cortical modules specialized for the perception of a single direction of motion might be larger than previously thought. Third, lesion analysis showed that unilateral damage, not only the human homologue of MT/V5 but also to parieto-occipital cortex, leads to MB.

Purpose With a retinal prosthesis connected to a head-mounted camera (camera-connected prosthesis [CC-P]), subjects explore the visual environment through head-scanning movements. As eye and camera misalignment might alter the spatial localization of images generated by the device, we investigated if such misalignment occurs in blind subjects wearing a CC-P and whether it impacts spatial localization, even years after the implantation. Methods We studied three subjects blinded by retinitis pigmentosa, fitted with a CC-P (Argus II) 4 years earlier. Eye/head movements were video recorded as subjects tried to localize a visual target. Pointing coordinates were collected as subjects were requested to orient their gaze toward predetermined directions, and to point their finger to the corresponding perceived spot locations on a touch screen. Finally, subjects were asked to give a history of their everyday behavior while performing visually controlled grasping tasks. Results Misaligned head and gaze directions occurred in all subjects during free visual search. Pointing coordinates were collected in two subjects and showed that median pointing directions shifted toward gaze direction. Reportedly all subjects were unable to accurately determine their eye position, and they developed adapted strategies to perform visually directed movements. Conclusions Eye position affected perceptual localization of images generated by the Argus II prosthesis, and consequently visuomotor coordination, even 4 years following implantation. Affected individuals developed strategies for visually guided movements to attenuate the impact of eye and head misalignment. Our observations provide indications for rehabilitation procedures and for the design of upcoming retinal prostheses. (ClinicalTrials.gov number, NCT00407602.).

In humans, the perception of vertical is provided by input from various sensorineural organs and pathways: vision, eye-movements, and proprioceptive and vestibular cues, particularly from the otolithic organs and graviceptive pathways. Well known in several types of brainstem lesions, subjective visual vertical (SVV) abnormalities may also be observed after peripheral vestibular lesions, such as surgical deafferentation, with a deviation directed toward the operated ear. Subjective visual vertical abnormalities are presumably related to a lesion of the otolithic organs and/or to changes in the afferent graviceptive pathways. The goal of this prospective study was to measure the SVV and to define the influence of the otolithic organs in patients suffering from various types of peripheral vestibular diseases: unilateral sudden cochleo-vestibular loss, so-called "viral labyrinthitis" (VL), sudden idiopathic unilateral peripheral vestibular loss, so-called "vestibular neuritis" (Ne). Data were compared with findings after unilateral surgical deafferentations such as vestibular neurectomy (VN) and labyrinthectomy (Lab). Subjective visual vertical was measured with a binocular test (vertical frame) and a monocular test (Maddox rod). In all patients, after VN and Lab, the SVV showed a 10-30 degrees tilt with the vertical frame (N: 0 +/- 2 degrees), 5-15 degrees with the Maddox rod (N: 0 +/- 4 degrees). With the vertical frame, SVV was tilted > 2 degrees in VL (47%) and in Ne (37%); the Maddox rod showed a > 4 degrees tilt in VL (41%) and in Ne (42%). The tilt was directed toward the affected ear. Our results demonstrate that SVV is frequently tilted in acute peripheral vestibulopathies such as VL and Ne. These findings suggest that otolithic function is implicated in the deficit depending on the extent and/or the localisation of the peripheral vestibular lesion.

To investigate the use of several preferred retinal loci (PRL) when attempting to read, two patients with bilateral central scotomas were asked to decipher single words, successively projected onto the retina using a scanning laser ophthalmoscope (SLO). Video-recordings of the fundus image, on which the projected targets were superimposed, were analyzed frame by frame. One patient used two PRL in association and the other used three, each PRL having a specific function. Single word reading made it easier than with full texts to correlate the images parts scrutinized and the retinal areas involved. Then, as patients were unable to describe their reading behavior, the examiner monitored refixation movements using the SLO and asked questions to help them to become aware of their reading behavior. Eventually, they could localize their PRL, describe their specific functions, and switch at will between them.

Background: We present the description of a successful outcome in a case of varicella-zoster virus (VZV) acute retinal necrosis (ARN). History and signs: A healthy 40-year-old patient was admitted for a VZV retinitis. Therapy and outcome: 10 days after the onset of intravenous (i.v.) acyclovir treatment, new small peripheral retinal necrotic lesions appeared in the right eye. A viral resistance was suspected and the acyclovir therapy was optimised with i.v. foscarnet combined with 2 intravitreal injections of ganciclovir. The outcome was favourable with a final vision of 1.0 after a follow-up of 30 months. No systemic or local complications were observed. Conclusions: VZV ARN is a severe infection with a poor prognosis. This case demonstrates that combination of antiviral therapies given intravenously (acyclovir + foscarnet) and in the vitreous (ganciclovir) may be safe and efficacious in the management of necrotising herpetic retinopathies affecting immunocompetent patients.

Background: To describe indocyanine green (ICG) angiography (ICGA) findings and clinical features of endogenous mycotic endophthalmitis. Patients and methods: Two patients (a female 62 years, a male 31 years) were addressed to investigate a progressive unilateral visual loss. Slit-lamp examination disclosed a macular chorioretinitis. A clinical work-up revealed a mycotic infection (Candida albicans). Before treatment an ICGA was performed. Results:ICGA early frames disclosed hypofluorescent lesiohs. Progressively, the lesions were surrounded by a slight hyperfluorescence, although the centre of the lesions was still hypofluorescent. Conclusions: The presence and persistence of a hypofluorescent lesion, after introducing a specific treatment, led us to suspect a necrotic/ischaemic process affecting the choroidal vascular bed. ICGA provided additional information regarding the pathophysiological process and the patient's functional visual recovery.

Purpose This study evaluated the Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc., Sylmar, CA) in blind subjects with severe outer retinal degeneration. Design Single-arm, prospective, multicenter clinical trial. Participants Thirty subjects were enrolled in the United States and Europe between June 6, 2007, and August 11, 2009. All subjects were followed up for a minimum of 6 months and up to 2.7 years. Methods The electronic stimulator and antenna of the implant were sutured onto the sclera using an encircling silicone band. Next, a pars plana vitrectomy was performed, and the electrode array and cable were introduced into the eye via a pars plana sclerotomy. The microelectrode array then was tacked to the epiretinal surface. Main Outcome Measures The primary safety end points for the trial were the number, severity, and relation of adverse events. Principal performance end points were assessments of visual function as well as performance on orientation and mobility tasks. Results Subjects performed statistically better with the system on versus off in the following tasks: object localization (96% of subjects), motion discrimination (57%), and discrimination of oriented gratings (23%). The best recorded visual acuity to date is 20/1260. Subjects' mean performance on orientation and mobility tasks was significantly better when the system was on versus off. Seventy percent of the patients did not have any serious adverse events (SAEs). The most common SAE reported was either conjunctival erosion or dehiscence over the extraocular implant and was treated successfully in all subjects except in one, who required explantation of the device without further complications. Conclusions The long-term safety results of Second Sight's retinal prosthesis system are acceptable, and most subjects with profound visual loss perform better on visual tasks with system than without it. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references.

MEWDS is a benign acquired disorder of the retinal pigment epithelium of unknown etiology which has been first described in 1984. Actually more than 50 cases have been reported worldwide but only 5 cases from Europe. We report 10 other cases of MEWDS, seen in the past 5 years. Their clinical presentation, perimetric and electroretinographic results, as well as their differential diagnosis will be reported.

BACKGROUND: In vivo confocal microscopy (IVCM) is a newly developed application to assess corneal nerve morphology. The purpose of the study is to evaluate the role of IVCM in the assessment of various types of polyneuropathy, and to define alterations of corneal nerves in such conditions. PATIENTS AND METHODS: Eighteen patients with various types of polyneuropathy were characterized by clinical neurological and ophthalmic examinations, as well as by electroneuromyography (ENMG). Full thickness IVCM of corneal nerves was carried out on all patients and 15 age-matched eyes using Heidelberg Retina Tomograph II (HRT II). The subbasal nerve plexus were statistically analysed regarding long nerve fiber density, nerve branch density, nerve thickness, nerve bead number and nerve tortuosity. RESULTS: In subbasal nerve plexus, the following three parameters were significantly reduced in patients with polyneuropathy compared to controls: long nerve fibre density (p < 0.01), nerve branch density (p < 0.001), and nerve bead number (p = 0.001). In addition, the average grade of nerve tortuosity was 2.87 +/- 0.97 in the polyneuropathic group and 1.17 +/- 0.68 in the control group (p < 0.0001). CONCLUSIONS: IVCM allows a non-invasive, in vivo study of corneal nerves with high resolution. It therefore appears invaluable in clinical investigations. IVCM appears to be valuable in a large variety of polyneuropathic conditions.

Although neurologic complications are frequent in the acquired immunodeficiency syndrome, their incidence and progression in early human immunodeficiency virus (HIV) infection remain controversial. The goal of this study was to assess neurologic manifestations in asymptomatic carriers of HIV.We studied 29 HIV-seropositive homosexual men and 33 seronegative homosexual controls by means of neurologic and neuropsychological examinations, magnetic resonance imaging (MRI), and electrophysiologic tests (electroencephalography, multimodal evoked-potential tests, and otoneurologic tests). After six to nine months, the tests were repeated in 27 seropositive men and 30 controls. The investigators were blind to the serologic status of the subjects.The seropositive subjects had a mean CD4+ lymphocyte count of 635 X 10(6) per liter. Neurologic and neuropsychological examination, MRI, and measurements of pattern visual evoked potentials did not show significant differences between the two groups. The latencies of the median-nerve somatosensory evoked potentials were slightly prolonged in the seropositive men. The initial electroencephalogram was judged abnormal in 8 of 27 of the seropositive subjects (30 percent) as compared with none of the controls, with a slowing of fundamental activity, anterior spread [corrected] of alpha rhythm, subnormal reactivity, and unusual anterior theta activities. These findings were confirmed by computerized spectral analysis. The second electroencephalogram was abnormal in 10 of 25 of the seropositive men (40 percent). The otoneurologic evaluation identified abnormalities in the central auditory or vestibulo-ocular pathways in 34 percent of the seropositive men (10 of 29), as compared with 6 percent of the controls (2 of 33), on the first examination and in 44 percent (12 of 27) and 7 percent (2 of 30), respectively, on the second examination. Altogether, electrophysiologic abnormalities were found in 67 percent of the seropositive men (18 of 27) and 10 percent of the controls (3 of 30) (P less than 0.00005).In persons with asymptomatic HIV infection, electrophysiologic tests may be the most sensitive indicators of subclinical neurologic impairment. Electrophysiologic abnormalities are far more common in asymptomatic carriers of HIV than in controls and tend to progress over time.

Study of a father and son who had helicoid peripapillary chorioretinal degeneration suggests that a progressive tearing and retraction of the retinal pigment epithelium or of Bruch's membrane around the optic disk may be involved in the disorder's pathogenesis. We presume that this tearing results primarily from dysplastic abnormalities of the retinal pigment epithelium that surrounds the optic disk. The dystrophic lesions progress slowly and may affect the macula and even the peripheral retina.

After a low brainstem stroke, a 73-year-old man experienced episodes of 90 degrees tilting of the visual environment in the sagittal plane evoked or terminated by voluntarily changing his head position. The episodes ceased 10 days after the stroke. This provocation by head position supports the idea that pathologic visual-vestibular interaction is at the basis of the room tilt illusion.

Retinal prostheses attempt to restore some amount of vision to totally blind patients. Vision evoked this way will be however severely constrained because of several factors (e.g., size of the implanted device, number of stimulating contacts, etc.). We used simulations of artificial vision to study how such restrictions of the amount of visual information provided would affect performance on simple pointing and manipulation tasks. Five normal subjects participated in the study. Two tasks were used: pointing on random targets (LEDs task) and arranging wooden chips according to a given model (CHIPs task). Both tasks had to be completed while the amount of visual information was limited by reducing the resolution (number of pixels) and modifying the size of the effective field of view. All images were projected on a 10 degrees x 7 degrees viewing area, stabilised at a given position on the retina. In central vision, the time required to accomplish the tasks remained systematically slower than with normal vision. Accuracy was close to normal at high image resolutions and decreased at 500 pixels or below, depending on the field of view used. Subjects adapted quite rapidly (in less than 15 sessions) to performing both tasks in eccentric vision (15 degrees in the lower visual field), achieving after adaptation performances close to those observed in central vision. These results demonstrate that, if vision is restricted to a small visual area stabilised on the retina (as would be the case in a retinal prosthesis), the perception of several hundreds of retinotopically arranged phosphenes is still needed to restore accurate but slow performance on pointing and manipulation tasks. Considering that present prototypes afford less than 100 stimulation contacts and that our simulations represent the most favourable visual input conditions that the user might experience, further development is required to achieve optimal rehabilitation prospects.

Summary: Purpose: The risk factors for visual field loss attributable to vigabatrin (VAVFL) are equivocal. This multinational, prospective, observational study aimed to clarify the principal/major factors for VAVFL. Methods: Interim analysis of three groups with refractory partial epilepsy, stratified by age (8‐12 years; >12 years) and exposure to vigabatrin (VGB). Group I comprised participants treated with VGB for ≥6 months, Group II participants previously treated with VGB for ≥6 months who had discontinued the drug for ≥6 months and Group III those never treated with VGB. Perimetry was undertaken at least every six months, for up to 36 months; results were evaluated masked to drug exposure. Results: Based upon 563 participants in the locked data set, 432 yielded one or more Conclusive visual field examinations. For Group I, the frequency of VAVFL at the last Conclusive examination was 10/32 (31.2%) for those aged 8‐12 years and 52/125 (41.6%) for those aged >12 years. For Group II, the proportions were 4/39 (10.3%) and 31/129 (24.0%). No cases resembling VAVFL manifested in Group III. VAVFL was associated with duration of VGB therapy (Odds ratio [OR] 14.2; 95% CI 5.0 to 40.5); mean dose of VGB (OR 8.5; 95% CI 2.2 to 33.2); and male gender (OR 2.1; 95% CI 1.2 to 3.7). VAVFL was more common with static than kinetic perimetry (OR 2.3, 95% CI 1.3 to 4.2). Conclusions: The therapeutic benefit of VGB is counteracted by the progressive accrual of the risk of VAVFL with continued exposure and with increase in mean dose.

Serpiginous choroidopathy (SC) is a rare disease inducing a permanent loss of vision, caused by a progressive destruction of the retinal pigment epithelium and choriocapillaris. Until now, no aetiology or predisposing factors have been reported. SC, usually, affects both eyes and occurs in patients between the fourth and sixth decade, without any sex or race predilection. Clinically, deep cream-coloured lesions develop in the peripapillary region and then along the retinal vessels, centrifugally, inducing an atrophy of the retina. Other lesions may develop, isolated, in the posterior segment. The anterior segment is typically quiet; nevertheless, a mild anterior uveitis and/or vitritis have been observed. The course of the disease results in successive attacks and recurrences inducing permanent retinal atrophic changes and subsequently an irreversible loss of vision. Choroidal neovascularisation may occasionally develop. No specific diagnostic tests are available such that the diagnosis of SC is mostly clinical.1 A 30 year old Indian man presented with a history of painless progressive visual loss affecting the right eye. No other ophthalmological or systemic complaints were present. His medical history was unremarkable. Ophthalmological examination revealed a visual acuity of 20/50 in the right eye and 20/20 in the left eye without a correction in both eyes. Anterior segment examination revealed a mild inflammation with fine keratic precipitates on the inferior …

BACKGROUND: Postoperative bacterial endophthalmitis is caused by the patient's endogenous flora in most cases (80 %). Pasteurella multocida (PM) is a Gram-negative coccobacillus found in the upper respiratory tract of dogs and cats and is very rarely implicated in postoperative endophthalmitis. HISTORY AND SIGNS: We describe a case of PM endophthalmitis that developed after cataract surgery. THERAPY AND OUTCOME: Cultures of both the conjunctiva and the aqueous humor were positive for PM. Topical, intravitreous and intravenous antibiotics were administered. Despite treatment, the outcome was unfavourable and complicated by a corneal perforation. CONCLUSIONS: The prognosis of postoperative PM endophthalmitis remains poor, despite adequate treatment of the infection. A history of recent pet exposure should alert physicians to this possible aetiological factor.

Reading of isolated words in conditions mimicking artificial vision has been found to be a difficult but feasible task. In particular at relatively high eccentricities, a significant adaptation process was required to reach optimal performances [Vision Res. 43 (2003) 269]. The present study addressed the task of full-page reading, including page navigation under control of subject's own eye movements. Conditions of artificial vision mimicking a retinal implant were simulated by projecting stimuli with reduced information content (lines of pixelised text) onto a restricted and eccentric area of the retina. Three subjects, naive to the task, were trained for almost two months (about 1 h/day) to read full-page texts. Subjects had to use their own eye movements to displace a 10 degrees x 7 degrees viewing window, stabilised at 15 degrees eccentricity in their lower visual field. Initial reading scores were very low for two subjects (about 13% correctly read words), and astonishingly high for the third subject (86% correctly read words). However, all of them significantly improved their performance with time, reaching close to perfect reading scores (ranging from 86% to 98% correct) at the end of the training process. Reading rates were as low as 1-5 words/min at the beginning of the experiment and increased significantly with time to 14-28 words/min. Qualitative text understanding was also estimated. We observed that reading scores of at least 85% correct were necessary to achieve 'good' text understanding. Gaze position recordings, made during the experimental sessions, demonstrated that the control of eye movements, especially the suppression of reflexive vertical saccades, constituted an important part of the overall adaptive learning process. Taken together, these results suggest that retinal implants might restore full-page text reading abilities to blind patients. About 600 stimulation contacts, distributed on an implant surface of 3 x 2 mm2, appear to be a minimum to allow for useful reading performance. A significant learning process will however be required to reach optimal performance with such devices, especially if they have to be placed outside the foveal area.

Behçet's disease is a chronic inflammatory disorder, clinically characterised by multisystemic vasculitis. Primary neurologic involvement in childhood is quite exceptional. We report a case of a child with recurrent venous thrombosis of the dural sinus. Behçet's disease was diagnosed.A 13-year-old boy from Eritrea was referred to our clinic with severe headaches and photophobia one month after onset. Ophthalmological examination disclosed a bilateral papilledema. Recurrent oral ulcers and pseudo-folliculitis were present. Pathergy test was positive.Complementary investigations disclosed an inflammatory syndrome. Computertomography was normal. Cranial magnetic resonance venography disclosed multiple cerebral sinus thrombosis (superior sagittal sinus, sigmoid sinus and lateral left sinus). There was no evidence of infectious, inflammatory or hypercoagulation disorder. A Behçet's disease was diagnosed based on the medical history and clinical examination. Whilst his general health deteriorated rapidly before treatment, he improved quickly after the onset of therapy with immunosuppression (Prednisone and Ciclosporine) in combination with anticoagulation (coumarin/Sintrom).Behçet's disease is uncommon and difficult to diagnose in children. Neurologic involvement as a first presentation is rarely described, but might be underestimated. We emphasise, therefore, the systematic application of magnetic resonance venography in children with unclear persistent headaches.

Background: Amyloidosis is an extracellular accumulation of a clear substance called amyloid in different organs. Fragments of identical proteinic chains are the components of this substance. Amyloidosis can be primary, secondary (chronic inflammation, multiple myeloma, tumour), senile or hereditary. History and signs: A 59-year-old healthy patient was referred with recurrent subconjunctival haemorrhages in his right eye since one year. The clinical examination disclosed the presence of yellowish subconjunctival deposits associated with haemorrhages. Therapy and outcome: Histopathologic examination of these deposits revealed the presence of amyloid. A complete work-up to exclude a systemic disease gave negative results. Conclusions: Primary conjunctival amyloidosis is a rare clinical entity that is mainly diagnosed histopathologically. In the presence of recurrent hyposphagma of unknown aetiology the diagnosis of amyloidosis should be excluded.

BACKGROUND: Behcet's disease is a chronic inflammatory disorder, clinically characterised by multisystemic vasculitis. Primary neurologic involvement in childhood is quite exceptional. We report a case of a child with recurrent venous thrombosis of the dural sinus. Behcet's disease was diagnosed. HISTORY AND SIGNS: A 13-year-old boy from Eritrea was referred to our clinic with severe headaches and photophobia one month after onset. Ophthalmological examination disclosed a bilateral papilledema. Recurrent oral ulcers and pseudo-folliculitis were present. Pathergy test was positive. THERAPY AND OUTCOME: Complementary investigations disclosed an inflammatory syndrome. Computertomography was normal. Cranial magnetic resonance venography disclosed multiple cerebral sinus thrombosis (superior sagittal sinus, sigmoid sinus and lateral left sinus). There was no evidence of infectious, inflammatory or hypercoagulation disorder. A Behcet's disease was diagnosed based on the medical history and clinical examination. Whilst his general health deteriorated rapidly before treatment, he improved quickly after the onset of therapy with immunosuppression (Prednisone and Ciclosporine) in combination with anticoagulation (coumarin/Sintrom). CONCLUSION: Behcet's disease is uncommon and difficult to diagnose in children. Neurologic involvement as a first presentation is rarely described, but might be underestimated. We emphasise, therefore, the systematic application of magnetic resonance venography in children with unclear persistent headaches.

A patient with chronic inflammatory demyelinating polyneuropathy (CIDP) presented with an isolated unilateral adduction deficit and ptosis. Investigations were negative until the onset of limb weakness and fatigue 2 years later. At that time, electroneuromyography, cerebrospinal fluid examination, and magnetic resonance imaging confirmed the diagnosis of CIDP. Thus, ophthalmic signs can precede extremity and bulbar signs with a long latency in CIDP.

We present a rare case of intraorbital ophthalmic artery aneurysm found incidentally, together with a ruptured aneurysm of the tip of the basilar artery. The intraorbital aneurysm was asymptomatic, and no treatment was offered. Angiographic control was recommended to detect any progression. Treatment may be indicated for documented enlargement or significant mass effect of the aneurysm.

A 74-year old man presented with horizontal diplopia of sudden onset, worsened by directing gaze to the left. His past medical history included arterial hypertension treated with an angiotensin conversion enzyme inhibitor, a 60pack-per-year smoking history and moderate alcohol consumption. Neurological examination showed moderate left VIth nerve paresis and slight paresis of the right arm and leg. Both spontaneous and voluntary facial movements were normal. Deep tendon reflexes were normal and symmetric. Cutaneous plantar response was flexor on both sides. There was no ataxia or sensory deficit. Gait was unremarkable. Laboratory examinations were normal except for slightly raised liver enzymes. Magnetic resonance imaging, performed 2 days after the onset of symptoms, showed a lesion in the left caudal ventral paramedian pons (Fig. 1a, b). Magnetic resonance angiography as well as extraand intracranial ultrasound with Doppler examination did not reveal any hemodynamically significant arterial stenosis. Heart rhythm remained regular during 24-h monitoring in the stroke unit. The patient was not handicapped by the slight hemiparesis; diplopia resolved partially over several days. Acetylsalicylic acid was introduced.

AIMS To investigate the reading strategy of a patient with central scotoma, using several preferred retinal loci (PRL). METHODS A 47 year old man with Stargardt9s disease was asked to decipher texts projected onto his retina using a scanning laser ophthalmoscope. A recording of the fundus image, on which the projected texts were superimposed, was analysed frame by frame. RESULTS The subject used a combination of three PRL, located above the scotoma and laterally to the left and right of it. He first used his left PRL to search for the beginning of a line, then switched to his right PRL, thus performing an apparent regression which was called “pseudo regression”, to read the line with successive rightward saccades. To decipher a particularly difficult word, he switched to his upper PRL, showing an apparent line loss which was called (“pseudo line loss”), and then used his three PRL in combination. CONCLUSION The patient used a complex, well structured reading strategy. These data showed that backward saccades and unexpected line losses, hitherto thought to be inappropriate and uneconomical, may in fact represent purposeful changes of PRL. It is thought that this is the first structured reading behaviour ever identified in such a condition. Such adaptive oculomotor behaviour should be taken into account when considering rehabilitation procedures.

In 74 normal subjects (62 children aged 5–8 years and 12 adults), we tested the widely-held belief that visual sensitivity improves substantially during childhood. Maturation of the retino-striate pathways is generally invoked to account for age-related changes in visual sensitivity. We evaluated the extent to which attentional factors unduly emphasized the effect of age on the purely physiological mechanisms. After a specially-designed familiarization procedure, sensitivity was fully evaluated at two locations in the superior temporal field using a bracketing technique (Octopus 2000R). False-positive (FP) and false-negative (FN) catch-trials were interspersed with the sequence of stimuli. Analyses demonstrated that: (1) age affected sensitivity; and (2) the general level of attentiveness varied not only with age, but also among subjects in the same age group. We then estimated the extent to which improved visual sensitivity may reflect a concomitant evolution of vigilance. Firstly, controlled variance analyses indicated that factors for evaluating attentiveness (rate of FN responses, slope of the psychometric function at the median, and goodness of fit) were indeed much better predictors than age of the sensitivity measured. Secondly and more significantly, the grouping of subjects into homogeneous subgroups, on the basis of their attentional performance, showed that children as young as 5 years may have a visual sensitivity that is only marginally lower than that of adults.

Vertical diplopia from skew deviation is well described in brainstem lesions. The phenomenon can also result from peripheral vestibular lesions. During the past years, we have observed these ocular changes in the acute stage following unilateral vestibular neurectomy and labyrinthectomy (n = 13), as well as in series of patients suffering from idiopathic sudden unilateral peripheral vestibular or cochleo-vestibular deficit (n = 5). Diplopia from skew deviation was noted immediately following ablative vestibular procedures; in patients with idiopathic vestibular deficit, it was observed as an associated sign. In all patients, clinical evaluation revealed an acute unilateral peripheral vestibular loss, with spontaneous nystagmus toward the unaffected ear and absence of nystagmic response to caloric testing on the affected ear. Skew deviation was measured using the Hess-Weiss test, which is based on the haploscopic principle. Static visual vertical was evaluated with the original methods of vertical frame and Maddox rod techniques. Photographs were made of the ocular fundi, to measure the degree of cyclotorsion of both eyes. In our patients, we found skew deviation with hypotropia of the eye that was ipsilateral to the affected ear and conjugated cyclotorsion and tilt of the static visual vertical on the side of the affected ear. Skew deviation was the first sign to disappear within a few days; conjugated cyclotorsion and tilt of the static visual vertical persisted for weeks to months. The eye-head postural reaction, consisting of head tilt, conjugated eye cyclotorsion, skew deviation, and alteration of vertical perception directed toward the side of the lesion, is known as the Ocular Tilt Reaction (OTR). The mechanism is presumably related to a lesion of the otolithic organs and/or to changes in the afferent graviceptive pathways. In man, the OTR is often mild and unrecognized, masked by spontaneous nystagmus and marked neuro-vegetative symptoms. Our observations indicate that skew deviation, as a part of the OTR, occurs in patients with sudden peripheral vestibular lesions, whether surgical or non-surgical in origin.

Purpose To evaluate the limitations, particularly those related to the perceptual completion phenomenon, of Amsler grid tests in patients with central scotomas caused by macular disorders. Methods We tested 15 affected eyes of 15 patients with macular lesions. In each subject, the central visual field was assessed by using four different types of Amsler grid testing and a tangent screen. Tests were conducted in a random order, and the sequence of tests was repeated once. The distance between the fixation point and the closest border of the plotted scotoma was assessed. For each patient, reproducibility in repeated examinations was evaluated by assessing changes in location of the computed center of the defects and by measuring changes in the position of the center of the scotoma. Results The tangent screen was more sensitive than Amsler grids in delineating the borders of the scotoma, and the results were more reproducible. Furthermore, by using a tangent screen, the fixation point was found adjacent to the scotoma. Conclusion Poor sensitivity and intraindividual variations found with Amsler grid testing are at least partly a result of the perceptual completion phenomenon. This phenomenon proved to be a dynamic and fluctuating process, as the results of two successive Amsler grid tests were not comparable, even when the technique was identical and the time between tests was no more than two to 15 minutes.

PURPOSE: To evaluate the incidence of visual hallucinations after macular photocoagulation for choroidal neovascularization. METHODS: After macular photocoagulation for choroidal neovascularization, 60 consecutive patients were asked to respond to an orally administered questionnaire. RESULTS: Twenty-seven patients (45%) described photopsias, flashing lights of various colors. Ten additional patients (16.6%) also described structured hallucinations, including known or unknown faces, flowers, and geometric patterns, which occurred hours or a few days after photocoagulation. Patients with structured hallucinations were older ( P = .04) and more often had subfoveal choroidal neovascularization ( P = .005) and severe macular disease in both eyes or at least in the treated eye ( P = .01). CONCLUSIONS: Visual hallucinations appear to be a frequent, albeit unrecognized, side effect of macular photocoagulation of choroidal neovascularization. The provision of proper information to patients may avoid concern about a psychiatric origin of their hallucinations.

Background After perinatal brain injury, clinico-anatomic correlations of functional deficits and brain plasticity remain difficult to evaluate clinically in the young infant. Thus, new non-invasive methods capable of early functional diagnosis are needed in young infants. Case Presentation The visual system recovery in an infant with perinatal stroke is assessed by combining diffusion tensor imaging (DTI) and event-related functional MRI (ER-fMRI). All experiments were done at 1.5T. A first DTI experiment was performed at 12 months of age. At 20 months of age, a second DTI experiment was performed and combined with an ER-fMRI experiment with visual stimuli (2 Hz visual flash). At 20 months of age, ER-fMRI showed significant negative activation in the visual cortex of the injured left hemisphere that was not previously observed in the same infant. DTI maps suggest recovery of the optic radiation in the vicinity of the lesion. Optic radiations in the injured hemisphere are more prominent in DTI at 20 months of age than in DTI at 12 months of age. Conclusion Our data indicate that functional cortical recovery is supported by structural modifications that concern major pathways of the visual system. These neuroimaging findings might contribute to elaborate a pertinent strategy in terms of diagnosis and rehabilitation.

We treated five patients with vestibular neuritis who had strabismus. Three of them spontaneously noted vertical diplopia. During the following weeks and months, strabismus progressively resolved, indicating the recently acquired nature of the oculomotor condition. In three of these individuals, a change in visual vertical and cyclo-torsion of the globes suggested that strabismus was a form of skew deviation that occurred as a part of an ocular tilt reaction resulting from the peripheral vestibular lesion. Strabismus appears to occur frequently in this common vestibular condition.

Twelve consecutive patients (17 eyes) with tilted disc syndrome underwent quantified visual field examination with the G1 Octopus program (Interzeag AG, Schlieren, Switzerland). Visual fields were abnormal in all cases. Although field loss was more pronounced in the superotemporal quadrant (P less than .001), it also involved the other three quadrants, thus demonstrating that optic nerve hypoplasia in tilted disc syndrome is apparently not entirely sectorial. Linear regression analysis showed that an increase in mean defect correlated with increase in myopic refractive error (P less than .05). However, the increase in myopic refractive error was found to be related to a decrease in corrected loss variance (P less than .05), indicating that in tilted discs with higher myopia, field loss is more homogeneous. With this series of patients, short-term fluctuation was within normal ranges in all visual fields, showing that this may be an additional clue for differential diagnosis from acquired disorders.

We studied two patients with eyelid nystagmus induced by ocular convergence. The first patient, a 29-year-old man, had the signs of a cerebellar syndrome after sustaining severe craniocerebral injuries. The second patient, a 12-year-old girl, had a tumor of the anterior vermis cerebelli. After treatment with corticosteroids (Patient 1) and surgery (Patient 2), the eyelid nystagmus gradually disappeared. An alteration in the cerebellar system is the most likely cause of convergence-evoked nystagmus.

Computed tomography (CT) now enables the early diagnosis of pituitary apoplexy. Since CT can detect blood, it can document acute or chronic hemorrhage in pituitary adenomas. In addition, CT can discriminate between densities other than blood and can therefore be used to diagnose those cases of pituitary apoplexy in which infarction and necrosis predominate. These conclusions were verified by a review of 10 apoplectic patients studied by CT. Although nine diagnostic delays occurred tissue confirmation by surgery in eight cases and autopsy on one made us familiar with the CT findings which should be useful in future diagnosis.

• Painful dysesthesia in association with ocular motor palsies characterized intraneural carcinomatous invasion in a 48-year-old man. Transcranial biopsy of the cavernous sinus stopped the pain; the specimen confirmed the diagnosis and provided the rationale for radiation therapy. One year after treatment, the patient was healthy and pain-free, with improved ocular motor function. The source of the carcinoma remains unknown.

Ro 15-1788 is a specific benzodiazepine antagonist, which has also been shown to have some agonist properties. Since benzodiazepine receptors are involved in the physiological mechanisms of vision, a possible intrinsic effect of Ro 15-1788 was sought in 6 healthy volunteers by study of psychophysical flicker thresholds, including critical fusion frequency and low frequency modulation threshold, and pattern reversal visual evoked response, using double blind cross-over methodology. In each session 2 tablets of Ro 15-1788 30 mg were administered. Using a two factorial univariate analysis of variance, no change was detected in any of the parameters studied.