Combined and separate effects of eye patching and visual stimulation on unilateral neglect following stroke

In Experiment 1, 11 of 13 stroke patients with left-sided neglect benefitted from monocular patching in at least one (of five) tests of neglect. This beneficial effect in most cases was limited to the period when the patch was worn. In Experiment 2, another group of stroke patients (n = 18) with left-sided neglect were tested in a line-bisection task with monocular patching and/or lateralized visual stimulation--a procedure previously shown to reduce neglect. Each procedure resulted in substantial benefits; the two procedures combined resulted in significantly larger benefits than either alone. As in Experiment 1, the degree of benefit of patching (alone or in combination with stimulation) was not related to several demographic factors. These findings suggest that monocular patching, together with lateralized visual stimulation, may significantly reduce neglect in daily activities and may be more beneficial than procedures requiring patients to be aware of their disorder and to use strategies for scanning the neglected side.

[The importance of the pleoptophor in treating children with amblyopia]

The author presents her own experience in pleoptic treatment, using the occlusion and the exercises at the amblyophor, on 161 children, during a 12 years period of time. The results of the therapy lead to cure in 38% of cases, to improvement in 46% of cases and fail in 16% of cases. The indications, the preparation, the practical development of the treatment at pleoptophor are discussed; the reasons of the failures are carefully analyzed. It is emphasized that the good results are due to the tracking down of children with strabismus in kindergartens, to the application of the amblyopic preventive optical treatment and to pleoptic treatment maintained for years with monthly checkups to prevent relapses.

[Prevention of amblyopia by active production of the macular fixation reflex in infants]

Among 1455 examined babies aged 3 months the authors found a lack of normal fixation reflex in both eyes in 155 and in 52 in one eye only. In these eyes the parents applied 3 times a day an alternate occlusion of eyes or of the master eye only showing the babies interesting toys. After 2 weeks 83 babies showed normalization of fixation and after following 2 weeks of over described occlusion only 8 of them did not reveal a normal fixation reflex. These babies exhibited also a convergent squint. The pleoptic treatment by means of an euthyscope was installed, followed by normalization of the fixation reflex in 3. The rest of the patients was treated with spheroprismatic glasses by localization method.

[Diagnosis and treatment of ophthalmoplegia]

The author discusses the signs and symptoms appearing in the course of so called noncommittant squints. Noncommittant squints are divided into squints caused by paresis or by a total paralysis of the motor muscles. One can divide the therapeutical procedure into the conservative and surgical treatment. The conservative treatment is carried out for one year since the onset of the palsy. After 12 months in the case of a lack of improvement a surgical intervention is performed. Surgical operations are divided into 3 types: 1) Rotation of the eye, that is to say operation of a recession-resection type--on the affected eye, 2) the principle paresis-counter-paresis or interventions performed on the muscles of the healthy eye, 3) transpositions of the muscles.

The prism bar--Prentice and frontal positions

The prism cover test has been in use for many years for measuring ocular alignment. The measurements obtained are used for both calculating the amount of correction needed in strabismus surgery, and monitoring any change in ocular alignment with recovery from muscle imbalance. Variability may arise from its use in either the frontal position or the Prentice position. Most prism bars used in the United Kingdom are calibrated for use in the Prentice position. Inaccurate results arise when a prism bar is used in a position for which it is not calibrated. The theoretical calculation for adjusting measurements obtained in the frontal position with prisms calibrated for use in the Prentice position was assessed clinically. A new modified equation is proposed incorporating practical aspects of performing the prism cover test. A table of values is included to assist in determining the necessary adjustment, so allowing for a more reliable assessment.

Accommodative rock via computer

A technique is presented for using a computer for the measurement as well as the training of accommodative facility. The testing and training are accomplished optically without any mechanically moving parts.

Visual therapy results for convergence insufficiency: a literature review

This paper is a review of the literature relative to treatment results for convergence insufficiency utilizing vision therapy training procedures. Vision therapy is shown to improve the nearpoint of convergence and fusional convergence and to ameliorate associated symptoms. The overall cure rate is 72%. Furthermore, the training results appear to persist for at least 2 years if the patients are initially cured and are independent of age until the late presbyopic years. Also, recent studies indicate the type of training procedures which yield the most effective training results.

Orthoptic treatment of vertical deviations

Four patients with large vertical deviations were treated with a combination of prismatic glasses and orthoptics. The least amount of prism which eliminated diplopia, followed by horizontal fusional range extension, was prescribed. After vergences were normalized the prism was further reduced by two prism diopters and horizontal fusional range extension was repeated. This process was repeated until either a plateau was achieved or the prism was eliminated. All four patients completed therapy with almost total alleviation of symptoms and elimination of full-time prismatic correction.

A model of spatial localization and its application to strabismus

Visually guided, spatially oriented behavior involves an ongoing integration of signals regarding the loci of the retinal images and the position and orientation of the eye. In the strabismic this requires an altered spatial metric resulting from a functional readaptation to avoid confusion and diplopia. A comparator mechanism for evaluating these two signals is presented. A case report using "disruptive" therapeutic procedures that deliberately alter the strabismic's visual-postural control system is presented. A treatment plan for altering the anomalous binocular link, a characteristic of the well adapted strabismic, is described and related to the comparator mechanism.

Predictive value of Lang two-pencil test, TNO stereotest, and Bagolini glasses. Orthoptic examination of an adult group

In our comparative study of a Rodenstock sight-screener and a clinical eye examination, an orthoptic examination was included. The present study describes the orthoptic examination of 109 subjects and evaluates the predictive diagnostic value of Lang two-pencil test, TNO stereotest and Bagolini striated glasses. We found 14 orthoptic pathological cases most of which could be revealed by an accurate cover test. The TNO stereotest and the Bagolini glasses have high predictive diagnostic values of negative and even of positive tests. If one of these tests is used as a supplement to the ophthalmological examination and anamnesis, we find it to be a valuable hint of orthoptic normality or abnormality. If an orthoptic pathology is suggested, this must be followed by a complete orthoptic examination concerning diagnosis and treatment.

Exotropia associated with defective accommodation

Despite the close association of convergence and accommodation, accommodative dysfunction is not often associated etiologically with exotropia. We studied 13 adolescent and young adults having intermittent exotropia and severely reduced accommodative function. Most patients had a prolonged history of visual symptoms that had not responded to therapy in the past. Clinical testing indicated that the patients had severely reduced amplitudes of accommodation and difficulty sustaining accommodation. Exotropia was manifest when the accommodative response was inadequate; relative orthophoria existed when the accommodative response was adequate. Treatment of the accommodative defect as well as the strabismus was successful for some patients. We recommend careful evaluation of accommodation for adolescent and young adults with exotropia to rule out an accommodative defect as a contributing cause.

Management of a young esotrope using vision therapy and prismatic prescription

This case report illustrates the important issues concerning optometric management of the pediatric patient presenting with esotropia. Appropriate treatment options and prognostic factors are covered. The case demonstrates the successful, sequential treatment of a young, early-onset, esotropic patient through vision therapy and prismatic lens prescription.

Efficacy of computerized vergence therapy

The purpose of this study was to determine the efficacy of computerized fusional vergence therapy and the effect of two different vergence training velocities. Six subjects received positive vergence training using a slow vergence training rate (0.75 delta/s) and six subjects received positive vergence training using a fast vergence training rate (5.00 delta/s). Six subjects served as controls and did not receive therapy. The duration of therapy was 80 min over a period of 4 weeks. All training activities were monitored. All vergence evaluations were double masked. Subjects using a slow training rate showed significant increases in positive vergence ranges as measured with the major amblyoscope, whereas subjects training with fast rates did not. We conclude that vergence therapy using a computerized video display is an effective technique for increasing the amplitudes of positive fusional vergence and that slower rates are more productive than faster rates.

Evaluation of colour vision, mesopic vision, visual evoked potentials and lightness discrimination in adult amblyopes

This is a study conducted on thirty adult strabismic and anisometropic amblyopes using colour vision tests, the lightness discrimination test, mesopic vision and visual evoked responses, in order to determine the probable site of the amblyopic defect. The results showed that, in its progressed stages, amblyopia is associated with eccentric fixation, abnormal hue discrimination, disturbed lightness discrimination and mesopic vision, and attenuation of the amplitude of the pattern visual evoked response. It is suggested that these abnormalities result from a defect involving the extrastriate higher visual association areas 18 & 19 of Brodmann.

Static vergence and accommodation: population norms and orthoptics effects

The steady-state characteristics of the accommodation and vergence systems can be described by a model with six major oculomotor parameters. These include the system biases (tonic vergence and accommodation) and forward-loop gains (vergence and accommodative gains), as well as the interactive system gains (AC/A and CA/C ratios). We investigated these parameters in two populations: (1) 22 visually-normal asymptomatic individuals, and (2) 21 visually-abnormal symptomatic individuals before and after conventional orthoptic therapy. Two parameters related to system gain differentiated between the symptomatic and asymptomatic individuals: the slope of the fixation disparity curve with accommodation open-looped and the slope of the accommodative response/stimulus curve. Following orthoptic therapy, 4 static model parameters and 1 dynamic clinical parameter showed changes toward the normal mean; this included tonic accommodation, slope of the fixation disparity curve with accommodation closed-loop (2.5D), slope of the accommodative response/stimulus curve, the CA/C ratio, and the +/- 2D monocular accommodative flipper rate.

Effect of visual training on the vertical vergence amplitude

Visual training has an effect on the vertical vergence amplitudes. Three mature symptomatic patients exhibited a significant increase in the vertical vergence which compensates for the vertical heterophoria. Subjects with normal binocularity and hence no vertical heterophoria did not exhibit increased vertical vergence amplitudes after training.

Clinical management of nearpoint stress-induced vision problems

Functional vision problems caused by or associated with nearpoint vision stress include: accommodative disorders (insufficiency, ill-sustained, infacility); abnormal heterophorias (esophoria, high exophoria); and vergence disorders. These vision disorders cause problems with acuity, comfort, and performance (efficiency). A combination of lens prescribing, vision therapy, and work/study visual hygiene recommendations can eliminate or greatly reduce nearpoint stress-induced vision problems.