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1.
Clifton Schor 《Documenta ophthalmologica. Advances in ophthalmology》1978,46(1):149-160
Suppression was examined with binocular perimetry in patients with small angle strabismus. Suppression stimuli were presented to the fovea of the fixating eye or 5 degrees nasal or temporal from the fovea. Suppression was found in the deviating eye of patients with normal or anomalous correspondence at retinal points corresponding to the retinal locus of the suppression stimulus. Suppression was demonstrated on both the nasal and temporal hemiretina of the deviating eye. Results indicate that zero retinal disparity is a strong stimulus for suppression in the central and peripheral visual field of patients with small angle strabismus.This study was supported by a grant, E4-20573, from the National Eye Institute. 相似文献
2.
Melanie van Waveren Herbert Jägle Dorothea Besch 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2013,251(2):575-584
Background
Hemianopia and strabismus leads to severe disturbance of visual orientation and diplopia under binocular conditions if the deviated eye has a normal retinal localization.Subjects and methods
Four cases with homonymous (two) and bitemporal (two) hemianopia and strabismus will be described with respect to binocular visual field and diplopia/confusion. All of them were recommended for strabismus surgery. Preoperatively, prism adaptation test was carried out to analyze functional results and fusional competence. In three of the four cases, strabismus surgery was successfully performed to avoid diplopia/confusion. All three patients revealed normal retinal correspondence. Furthermore, in two cases surgery led to an extension of binocular visual field; in one case with a bitemporal hemianopia and hemifield-slide phenomenon, blurred central vision and reading problems reduced significantly postoperatively. In one patient with anomalous retinal correspondence due to early childhood trauma exotropia led to an extension of the binocular visual field. In this case, strabismus surgery would have been unfavourable.Results
Case 1 showed a homonymous hemianopia to the left and acquired exotropia of the right eye, leading to binocular diplopia. Case 2 with homonymous hemianopia to the right and exotropia of right eye revealed anomalous retinal correspondence after history of perinatal brain injury, resulting in absence of diplopia and enlargement of visual field to the right. Cases 3 and 4 with bitemporal hemianopia suffered from sensory disturbances caused by additional acquired strabismus. The exodeviation of the right eye in case 3 led to a restriction of binocular visual field with overlap of the nasal parts causing diplopia, whereas the esodeviation of case 4 resulted in a “gap” between the nasal parts (blind area).Conclusion
Depending on the extent of visual field defects and on retinal correspondence, functional consequences for binocular vision and binocular visual field should be considered prior to surgery. In normal retinal correspondence, strabismus surgery will be indicated in most cases because of diplopia. However, surgery might result in a reduction of binocular visual field. Preoperatively, it is important to map monocular and binocular visual fields, to examine retinal correspondence, and to undertake prism adaptation test to imitate the postoperative functional result and risk of double vision. 相似文献3.
Prof. Dr E. C. Campos C. Chiesi 《Documenta ophthalmologica. Advances in ophthalmology》1983,55(4):277-293
Campos (1982a) reported on his psychophysical studies on the binocularity of patients with comitant strabismus. With binocular visual field techniques, it was possible to show that patients with small-angle eso- and exotropia exhibit a binocular vision, without suppression of the deviated eye. In the present paper visual electrophysiology is used to evaluate objectively these findings and to provide more insight in the problem. First, the studies on binocularity in normals and strabismics, done by using visual evoked responses (VER) are reviewed. This type of investigation is relatively new and the results of the literature are still conflicting. Then personal results of the authors are reported. It is shown that with VER it is possible to objectively assess the presence of anomalous binocular vision (ABV) sustained by anomalous retinal correspondence (ARC) in small-angle strabismus. In patients with large angle deviations this type of binocularity is absent. A correlation between psychophysical and electrophysiological data is provided. Lastly a simple method is described for differentiating the binocularity of normals from that of Strabismics with ARC. This method is based on the recording of binocular VER with the anteposition in front of the fixing eye of neutral filters of increasing density. 相似文献
4.
Binocular vision with primary microstrabismus 总被引:1,自引:0,他引:1
PURPOSE. Patients with primary microstrabismus have a high degree of binocularity, which suggests that their ocular misalignment may have a sensory rather than an oculomotor origin, as in large-angle strabismus. The purpose of these experiments was to determine whether microstrabismic subjects have sensory abnormalities that could give rise to a small angle of strabismus. METHODS. The binocular disparity response functions for sensory and motor processes were compared in seven orthotropic subjects and six strabismic subjects (four with primary microstrabismus and two with infantile esotropia). Binocularity was assessed by disparity vergence (central and peripheral stimuli) and depth discrimination (relative and absolute disparities) measures. Motor and sensory disparity response functions were both determined by psychophysical methods: vergence responses by dichoptic nonius alignment and sensory responses by forced-choice depth discrimination. RESULTS. All the strabismic subjects demonstrated normal retinal correspondence with peripheral binocular stimuli and anomalous retinal correspondence with central fusion stimuli. The microstrabismic subjects' disparity vergence responses with peripheral fusion stimuli were centered on disparities relative to their angle of strabismus. However, with central fusion stimuli, the disparity vergence responses were relative to the subjective angle of strabismus. The microstrabismic subjects' stereoacuities were substantially reduced, but their discrimination responses did not show an asymmetry indicative of an unrepresented population of disparity-selective mechanisms. CONCLUSIONS. The data do not support a sensory abnormality as the primary cause of microstrabismus. The results are not compatible with an oculomotor adaptation to an inherent anomalous correspondence or with a strabismus caused by an absence of a class of disparity-selective mechanisms. Thus, just as in large-angle strabismus, the anomalous retinal correspondence and defective stereopsis of microstrabismus appear to be consequences of abnormal visual experience caused by an interocular deviation. 相似文献
5.
G McCormack 《Investigative ophthalmology & visual science》1990,31(3):559-568
Burian proposed that a functional retinotopic remapping of the deviated eye on striate visual cortex may be the physiologic basis for the perceptual phenomenon of anomalous retinal correspondence (ARC) in human strabismus. This investigation searched for this type of retinotopic remapping in five esotropes and one exotrope with ARC by means of visual evoked potential (VEP) topographic mapping. Uniocular stimulation of the foveas (corresponding points) during binocular vision in a normal subject yielded identical VEP scalp topographies from each eye. Stimulation of anomalously corresponding points produced different VEP scalp topographies from each eye in the six strabismic subjects. Uniocular stimulation of the anatomic foveas of each eye (noncorresponding points) in a strabismic subject during binocular vision produced identical VEP scalp topographies. These results suggest that there is no significant functional binocular realignment of retinotopic mapping in the visual cortex of human strabismics with ARC. 相似文献
6.
Carlo Chiesi Aurelia Daniele Sargentini Roberto Bolzani 《Documenta ophthalmologica. Advances in ophthalmology》1984,58(1):51-56
Ten normal subjects and 14 patients with comitant esotropia were examined by means of pattern visual evoked responses (VER) under monocular and binocular viewing conditions. When both eyes were stimulated together a VER summation was noted both in normals and in strabismics with small-angle deviation and anomalous retinal correspondence (ARC). This is considered as an objective proof of binocularity. Patients with large-angle strabismus and/or suppression of the image of the deviated eye did not show summation. The significance of summation and its relationship with binocular vision was analyzed by recording binocular VER in normals in which diplopia was artificially induced and in strabismics who spontaneously exhibited double vision. A simple way for differentiating normals from strabismics by means of VERs is presented, considering that the presence or absence of summation per se does not achieve this result. This method is based on the anteposition in front of the fixing eye of neutral filters of increasing density. Summation disappears in strabismics with much weaker filters than in normals (0.5 versus 1.6 log. unit). 相似文献
7.
Volker Herzau Inge Bleher Elfriede Joos-Kratsch 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1988,226(2):148-149
A homonymous hemianopia can be compensated by a strabismus in the direction of the visual field defect if the deviated eye has a harmonious anomalous localization. This compensation is only partial; its extent corresponds to the angle of deviation. We report on two patients with a hemianopia to the left. Under binocular conditions the visual field defect was reduced by an exotropia of the left eye with panoramic vision. Unfortunately, up to now it has not been possible to induce such a sensory-motor compensation in cases of homonymous hemianopia with normal retinal correspondence in an adult visual system.Dedicated to Dr. G.K. von Noorden on the occasion of his 60th birthday 相似文献
8.
Arun Verma MS 《Annals of Ophthalmology》2007,39(2):95-106
Anomalous adaptive conditions (AAC) associated with strabismus include: suppression, amblyopia, abnormal retinal correspondence,
eccentric fixation, retinal rivalry, horror fusionis, and suspension. This article poses the hypothesis that AAC, in certain
cases, may be the cause of strabismus rather than the result of strabismus.
Dr. Arun Verma is from Dr. Daljit Singh Eye Hospital, Amritsar, India
The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer
or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes
unlabeled, unapproved, or investigative products or devices.
This article poses the hypothesis that anomalous adaptive conditions, in certain cases, may be the cause of strabismus rather
than the result of strabismus. 相似文献
9.
V. Herzau 《Documenta ophthalmologica. Advances in ophthalmology》1980,49(2):221-284
Sensory adaption, i.e. suppression and the status of retinal correspondence were examined with different methods using a special modification of the phase difference haploscope in 25 cases of eso- and 24 cases of exotropia. Three campimetric techniques were carried out:
- Haploscopic perimetry with moving and stationary targets (isopter and profile perimetry),
- suprathreshold haploscopic perimetry with a monocularly presented grid of 60 degrees in diameter (raster scotometry),
- contemporaneous stimulation with different quality of images for both eyes as far as color, direction of contours and luminance are concerned (‘Anteil’ perimetry).
10.
Some concepts regarding suppression, anomalous correspondence and amblyopia are revised according to the sensorial findings obtainable from esotropic patients directly in casual seeing (with the aid of the striated glasses test) and by grading a sensorial dissociating effect (with the aid of a bar of optical filters). The following points are emphasized: 1. Suppression appears to be minimal in small angle strabismus where diplopia seems mainly to be avoided by an anomalous correspondence mechanism. On the contrary, suppression is the prevalent mechanism in large angle strabismus. 2. The anomalous correspondence mechanism may lead to a weak type of anomalous binocular vision which is easily interrupted by light optical filters or by dissociating tests. 3. The subjective space of patients with anomalous binocular vision resembles that of normal binocular vision in some aspects. 4. The development of amblyopia is interpreted in the light of these new concepts on suppression and anomalous binocular vision. 5. Postoperatively, anomalous correspondence rapidly re-adapts to the smaller angle deviation and may normalize if the deviation is completely eliminated. This is evident only in casual seeing; for a certain time, dissociating tests reveal the preoperative correspondence status. This behaviour of correspondence in casual seeing has led to attempts at normalizing anomalous correspondence by prism therapy. Newly observed sensotio-motorial obstacles, however, have been found to frequently hamper treatment in casual seeing. 相似文献
11.
Presenting incompatible images to the eyes results in alternations of conscious perception, a phenomenon known as binocular rivalry. We examined rivalry using either simple stimuli (oriented gratings) or coherent visual objects (faces, houses etc). Two rivalry characteristics were measured: Depth of rivalry suppression and coherence of alternations. Rivalry between coherent visual objects exhibits deep suppression and coherent rivalry, whereas rivalry between gratings exhibits shallow suppression and piecemeal rivalry. Interestingly, rivalry between a simple and a complex stimulus displays the same characteristics (shallow and piecemeal) as rivalry between two simple stimuli. Thus, complex stimuli fail to rival globally unless the fellow stimulus is also global. We also conducted a face adaptation experiment. Adaptation to rivaling faces improved subsequent face discrimination (as expected), but adaptation to a rivaling face/grating pair did not. To explain this, we suggest rivalry must be an early and local process (at least initially), instigated by the failure of binocular fusion, which can then become globally organized by feedback from higher-level areas when both rivalry stimuli are global, so that rivalry tends to oscillate coherently. These globally assembled images then flow through object processing areas, with the dominant image gaining in relative strength in a form of 'biased competition', therefore accounting for the deeper suppression of global images. In contrast, when only one eye receives a global image, local piecemeal suppression from the fellow eye overrides the organizing effects of global feedback to prevent coherent image formation. This indicates the primacy of local over global processes in rivalry. 相似文献
12.
E. C. Campos 《Documenta ophthalmologica. Advances in ophthalmology》1982,53(3):249-281
A critical review is made of the literature on binocular perimetry in strabismus. A broad range of results was obtained by various authors, because different testing techniques were used. The concept of sensory testing of strabismic patients in casual seeing condition should be introduced also into binocular perimetry. Therefore a series of experiments is presented in which patients with small-angle comitant strabismus were tested. It was shown that: a) in small-angle esotropia the areas of single vision previously thought to be due to suppression are, instead, areas of binocular vision sustained by anomalous retinal correspondence (ARC); b) this can be seen only when using fusable stimuli as test targets; c) no suppression scotomas were found in patients with smallangle strabismus in the whole visual field; d) appropriate control-marks for binocularity are necessary, i.e. monocularly presented items. They influence the results, as well e) the area of binocular single vision in strabismus (called pseudo-Panum's area) is wider than the Panum's area of normals. Moreover it is easier to disrupt binocular cooperation sustained by ARC causing diplopia than binocular cooperation in normals; f) ARC seems to be more deeply rooted in the center than in the periphery of the visual field; g) superimposable findings were obtained in small-angle constant exotropia; h) in largeangle exotropia wide suppression scotomas were found, which often override the midline. Hemianopic suppression scotomas in exotropia can be found only when dissociating testing techniques are used; i) the same group of patients with small-angle esotropia was examined with the author's technique and with the classical method proposed by Harms. The results were strongly dependent on the method used and the same patient responded differently to the two tests.It is concluded that in small-angle strabismus there is an anomalous type of binocular single vision, which can be tested with binocular visual field techniques. This binocularity can only be found when non-artificial testing conditions are used.The usefulness of this anomalous binocular vision in the every day seeing condition of the patient is discussed. 相似文献
13.
Jeremiah I. Nelson 《Documenta ophthalmologica. Advances in ophthalmology》1981,51(1-2):3-100
Normal retinal correspondence is not stable. The arguments for the plasticity of correspondence in normal binocular vision have been given in two previous papers (Nelson, 1975, 1977). In this paper, both laboratory research and the clinical strabismus literature are reviewed to show similarities between normal and abnormal binocular vision. In particular, it is argued that sensory fusion (Panum's areas) and anomalous retinal correspondence (AC) obey similar principles, and so a sensory fusional model of AC may be developed.Recent advances in the neurophysiology of binocular vision are reviewed, but current laboratory knowledge cannot account for many phenomena known clinically unless certain postulates are made. Two hypothesized intracortical interactions among binocular disparity detectors, termed disparity domain inhibition and spatial domain facilitation, play key roles in extending the neurophysiology of binocular vision to an account of both normally - and clinically - observed plasticities of correspondence.The fusional model of retinal correspondence developed here from postulated domain interactions contrasts with the older concept of fixed corresponding points, an approach which has failed to provide a unified foundation for the treatment of normal and abnormal binocular vision. 相似文献
14.
K Holopigian 《Vision research》1989,29(10):1325-1333
In observers with abnormal binocular vision (such as strabismics or anisometropes) one eye's view is often suppressed. This clinical suppression serves to eliminate binocular diplopia and confusion. Suppression may also occur in observers with normal binocular vision, when the two eyes view disparate retinal images, a phenomenon known as binocular rivalry. When the image in an eye is suppressed, it is possible to determine the amount by which that suppressed stimulus is below the visibility threshold, or the depth of suppression. In the experiments presented here, the depth of suppression in an eye was measured as the strength of the stimulus in the contralateral eye (the stimulus inducing suppression) was varied. This was done for both clinical suppressors and normal observers undergoing binocular rivalry suppression. Independent changes were made to the contrast, the luminance, and the spatial frequency of the inducing stimulus. For both clinical suppression and binocular rivalry suppression, the depth of suppression was constant, regardless of the changes to the inducing stimulus. 相似文献
15.
Ebba Ch. Schwarz Michael Gerdemann Ricarda Hoffmann Christian Hartmann 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(10):635-639
Summary
In our Department of Orthoptics we have seen an increasing number of patients suffering from diplopia after cataract surgery
with IOL implantation. Between 1993 and 1997 the total number of patients with this problem was 24 (2.7 % of all patients,
mean age 71 years, age range 38–88). We addressed the question of whether there is a common pattern of motility dysfunction.
Methods: After evaluation of the clinical history and the basic ophthalmological findings the following parameters were examined:
binocular function (Bagolini test), squint angles (Maddox cross), ocular motility.
Results: The 24 patients could be divided up into three groups. Group 1 consisted of 9 patients (mean age 82 years, range 64–88) who
complained about diplopia because of strabismus incomitans with vertical deviation and restricted motility on the first day
after surgery. In 8 of the 9 patients strabismus surgery was done. Group II consisted of 10 patients (mean age 66 years, range
38–77) who noticed diplopia and strabismus within 7 days after surgery. We found various kinds of heterotropia. Seven of these
patients were operated on and two had a prism correction. Group III consisted of 5 patients (mean age 67 years, range 61–78).
Their already known strabismus paralyticus or concomitans deteriorated, leading to diplopia in some cases. All patients in
this group were operated on.
Discussion: For group I we believe that retro-, para- or peribulbar anesthesia caused the motility dysfunction. In groups II and III
it is unlikely that local anesthesia had a causative role. The prolonged disruption of binocular vision and the abrupt change
in the sensory situation after the cataract operation with lens implantation may be the leading causes for strabismus or deterioration
of a preexisting strabism, respectively.
Conclusions: These patients need a subtil meticulous diagnostic work-up and follow-up because of the possibility of early surgical therapy,
which has a good prognosis. Evaluation of binocular vision and eye movements prior to cataract surgery appears to be helpful
for later strabismic surgery.
相似文献
16.
The authors measured the time course of interocular suppression of five normal subjects and eleven patients with amblyopia (strabismic and/or anisometropic). Orthogonal gratings were presented dichoptically for durations that ranged from 10-6000 msec. All normal observers reported fusion or superimposition of the orthogonal gratings for short stimuli and reported binocular rivalry for stimuli longer than 150 msec. At long presentation times, all amblyopes constantly suppressed the pattern that was presented to their amblyopic eye. Six amblyopes showed superimposition of the two patterns at short presentation times. Of these, three had time courses similar to those of normal observers; the other three had a much shorter onset of suppression (about 80 msec). The remaining five amblyopes perceived only the pattern of the dominant eye at short stimulus durations; at intermediate durations, they reported partial superimposition of the stimuli, whereas at the longest stimulus durations, again only the stimulus of the dominant eye was perceived. The results suggest that binocular rivalry in normal observers and strabismic suppression in amblyopes are mediated by different mechanisms. The heterogeneity of the time courses of suppression in amblyopes might result from differences in the disturbances of early visual development (age at onset of strabismus and/or anisometropia, origin, and therapy). 相似文献
17.
Half-occluded points (visible only in one eye) are perceived at a certain depth behind the occluding surface without binocular rivalry, even though no disparity is defined at such points. Here we propose a stereo model that reconstructs 3D structures not only from disparity information of interocularly paired points but also from unpaired points. Starting with an array of depth detection cells, we introduce cells that detect unpaired points visible only in the left eye or the right eye (left and right unpaired point detection cells). They interact cooperatively with each other based on optogeometrical constraints (such as uniqueness, cohesiveness, occlusion) to recover the depth and the border of 3D objects. Since it is contradictory for monocularly visible regions to be visible in both eyes, we introduce mutual inhibition between left and right unpaired point detection cells. When input images satisfy occlusion geometry, the model outputs the depth of unpaired points properly. An interesting finding is that when we input two unmatched images, the model shows an unstable output that alternates between interpretations of monocularly visible regions for the left and the right eyes, thereby reproducing binocular rivalry. The results suggest that binocular rivalry arises from the erroneous output of a stereo mechanism that estimates the depth of half-occluded unpaired points. In this sense, our model integrates stereopsis and binocular rivalry, which are usually treated separately, into a single framework of binocular vision. There are two general theories for what the "rivals" are during binocular rivalry: the two eyes, or representations of two stimulus patterns. We propose a new hypothesis that bridges these two conflicting hypotheses: interocular inhibition between representations of monocularly visible regions causes binocular rivalry. Unlike the traditional eye theory, the level of the interocular inhibition introduced here is after binocular convergence at the stage solving the correspondence problem, and thus open to pattern-specific mechanisms. 相似文献
18.
When dissimilar stimuli are presented to each eye, perception alternates between both images--a phenomenon known as binocular rivalry. It has been shown that stimuli presented in proximity of rival targets modulate the time each target is perceptually dominant. For example, presenting motion to the region surrounding the rival targets decreases the predominance of the same-direction target. Here, using a stationary concentric grating rivaling with a drifting grating, we show that a drifting surround grating also increases the depth of binocular rivalry suppression, as measured by sensitivity to a speed discrimination probe on the rival grating. This was especially so when the surround moved in the same direction as the grating, and was slightly weaker for opposed directions. Suppression in both cases was deeper than a no-surround control condition. We hypothesize that surround suppression often observed in area MT (V5)-a visual area implicated in visual motion perception-is responsible for this increase in suppression. In support of this hypothesis, monocular and binocular surrounds were both effective in increasing suppression depth, as were surrounds contralateral to the probed eye. Static and orthogonal motion surrounds failed to add to the depth of rivalry suppression. These results implicate a higher-level, fully binocular area whose surround inhibition provides an additional source of suppression which sums with rivalry suppression to effectively deepen suppression of an unseen rival target. 相似文献
19.
Schrader WF Hauptmann S Hamburger G 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1999,96(2):102-107
Background: After vitreoretinal surgery the patient is at least temporarily unable to drive. Buckling procedures may cause refractive
changes, reduced motility or impaired binocular vision. We examined the ability of these patients to drive a car according
to German law after retinal surgery.
Patients and methods: The frequency and extent of changes interfering with driving ability were examined in 112 unselected patients 3.5 years (2–5
years) after successful buckling procedures. We used half-round buckling elements of 3–11 mm diameter or encircling bands
(2–3 mm). We examined visual acuity, frequency of permanent diplopia and field of normal binocular vision. Driving ability
was considered as impaired, when visual acuity was below 0.4 in the better eye or 0.2 in the worse eye, or when diplopia occurred
within a gazing field of 20 ° of diameter.
Results: Eighteen of 112 (16 %) patients reported diplopia within the first 3 months, so they were temporarily unable to drive. Two
to five years later 14 of 112 patients did not have sufficient visual acuity according to the German requirements. Another
2 patients had an impaired binocular vision, resulting in driving disability.
Conclusion: Driving ability may be temporarily restricted by double vision in 15 % of patients after successful buckling for retinal
detachment. Permanent driving ability is mainly impaired by macular involvement in retinal detachment. The type of buckling
procedure is of minor importance.
相似文献
20.
In binocular vision, even without conscious awareness of eye of origin, attention can be selectively biased toward one eye by presenting a visual stimulus uniquely to that eye. Monocularly directed visual cues can bias perceptual dominance, as shown by studies using discrete measures of percept changes in continuous-flash suppression. Here, we use binocular rivalry to determine whether eye-based visual cues can modulate eye balance using continuous percept reporting. Using a dual-task versus single-task paradigm, we investigated whether the attentional load of these cues differentially modulates eye balance. Furthermore, both color-based and motion-based cue stimuli, non-overlaid and peripheral to the rivalry grating stimuli, were used to determine whether shifts in eye balance were stimulus specific. Aligned to cue stimulus onset, time series of percept reports were constructed and averaged across trials and participants. Specifically, for the monocular attention conditions, we found a significant shift in eye balance toward the cued eye and a significant difference in the time taken to switch from the dominating percept, regardless of whether the attention stimuli is color based or motion based. Although we did not find a significant main effect of attentional load, we found a significant interaction effect between the attentionally cued eye and attentional load on the shift in eye balance, indicating an influence of monocular attention on the shift in eye balance. 相似文献