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Ocular involvement was found in 29 autopsied individuals with generalized vascular amyloidosis. It may be present both in clinically primary and secondary amyloidosis. In the latter form the choroid and the sclera are particulary involved, whereas in the orbit the most frequently affected tissues in both forms are the extraocular muscles. However, in most cases amyloid deposits are localized in the vessels of the aterial circle of Zinn-Haller. The retina showed no involvement in 28 of 29 cases while optic nerve fibres never were affected. The optic nerve dural sheath was slightly involved in 8 cases.

An interferometric acuity device (Takata) has been used to study visual resolution in individuals with possible demyelinating disease. The instrument employed provides a large field with a continuous range of grid or fringe frequencies and a relatively intense (10(5) mean photopic trolands) stimulus. After a brief period of time with eyes closed, resolution thresholds of patient are repeatedly determined during a five minute period. In all individuals suspected of having a demyelinating disease tested to date, a fall off in resolution capability has been found in time when using this intense stimulus display. This occurs whether eye signs have been present, are present or have not yet been observed. Normal observers do not exhibit comparable decrements. The fall off in resolution capability may or may not occur at lower stimulus levels, and is often not revealed when testing routine Snellen acuity. Outer and inner retinal pathology (division based on vascular support) do not cause a comparable fall off in resolution in time. The interferometric acuity test is a non-invasive, easily applied test.

The most widely-used techniques for testing visual function in babies are reviewed. Advantages and limitations of optokinetic nystagmus testing, visual evoked responses and preferential looking techniques are considered. The theoretical basis and the clinical applicability of those techniques are outlined. Other simple methods are considered as well, which allow practicing ophthalmologists to assess the presence or absence of vision in babies. The importance of early diagnosis for prevention and treatment of visual deficits in babies is stressed.

The fusional nature of the phenomenon of prism compensation in strabismus was studied. At first a general survey was performed on the characteristics of anomalous fusional movements (a.f.m.). The influence of different kinds of stimuli (foveal and peripheral fusionable targets, non-fusionable targets) on a.f.m. was considered, and finally the effect of a sensorial obstacle to fusion was investiaged. It is concluded that 'eating up' the prisms is definitely a phenomenon of fusional nature, although it has special features which are interpreted as a consequence of the initial pathological condition. In this way the puzzling prism compensation also in subjects with normal retinal correspondence may be explained.

A psychophysical function, believed to reflect receptive field-like properties, is described. It is based on the determination of the critical flicker fusion frequency (CFF) of a tiny test target, centered on a round background of fixed luminance, the size of which is varied as the test parameter. Under optimal conditions, the maximal obtained frequency difference is 10 Hz. This function is compared with the so-called sustained-like function, with which it has some common aspects. Additionally, a portion of the flicker-based function apparently derives from a non-sustained-like source.

The visual evoked response transfer function of amblyopic subjects was studied. Strabismic amblyopes showed abnormalities only in the high spatial frequency range. Anisometropic amblyopes on the contrary, showed an abnormal function both in the low and high spatial frequency range. This is an objective correlate of functional differences between strabismic and anisometropic amblyopes.

In this paper two relatively early cases of senile macular degeneration are compared by making use of a number of tests of visual function, some relatively new, coupled with observation of the fundus and analysis by fluorescein angiography. The functional tests include visual acuity, the sustainedlike and transientlike functions which are believed to test inner retinal receptive field properties and to have origin in the inner and outer plexiform layers, the Stiles-Crawford function which reflects the directional sensitivity and orientation of photoreceptors, and increment threshold curves. In one case there was evidence of inner retinal involvement at the time the tests were conducted, but, because the Stiles-Crawford function remained essentially normal, it is assumed that the receptors were not disturbed relative to their orientation. In this case (as in many others), the zone or area exhibiting functional change does not necessarily match the area exhibiting anatomical change as observed by examination of the fundus, fundus photography, and fluorescein angiography. In the second patient there is evidence of both anomalous inner retinal function and disturbance in receptor alignment. The later suggests disorientation of the receptor bed. These findings correlated with the fundus observation and fluorescein angiographic evidence of a leak, resulting in the presence of serous fluid beneath the neurosensory retina. With resolution of this fluid there was a return of the functional tests toward normal. At this time, it is not possible to determine whether, in two cases, the functional changes are proceeding on a parallel course, but are at different stages, or whether they are the expression of somewhat different anomalies.

Pathological changes in the visual system are often present in children with neurological handicaps. Strabismus, refractive errors, amblyopia, optic atrophy are the more frequent findings. The ophthalmological evaluation in these children includes: eliciting of pupillary light reflex; occlusion test; cover-test; observation of symmetry of corneal light reflexes; retinoscopy and ophthalmoscopy. Strabismus is the most frequent alteration. The so-called "caotic" strabismus, with very variable angle of squint and abnormalities of the vertical movements, is peculiar in children with neurological handicaps. Sensorial adaptation to strabismus can lead to: suppression, lack of fusion power, anomalous retinal correspondence, amblyopia; these sequelae are the same as those found in strabismic patients without neurological lesions. The basic aims of therapy are an energetic treatment of sensorial anomalies of strabismus, and the development of the best possible visual acuity in each eye. Surgical treatment has mainly cosmetic purposes. It tends to be delayed in time because the results are rather impredictable, owing to the variations of the angle of squint. It is stressed that surgical and non-surgical treatment of strabismus in children with neurological handicaps has no influence on their psycho-motor performances.

In discussing the relationship between anomalous retinal correspondence and amblyopia, it is suggested that amblyopia may be due not only to suppression and/or non-use of the deviated eye, but also to a mis-use of this eye. The interaction of the 'focal' and 'ambient' systems in amblyopia and the relationship of the 'ambient' system to the interocular transfer of the motion after-effect are discussed. This effect has been found to be of no clinical significance in predicting the presence or absence of binocular cooperation. It is concluded that in cases of amblyopia there is either no disturbance in the 'ambient' system or an adaptation of the latter to the pathological condition.

Patients with optic neuritis describe image fading which is particularly evident at bright light levels. The effect is dependent on adaptation level, and high adaptation levels serve as a provocative test. Kinetic and static perimetry and interferometric acuity tests repeated in time reveal this loss in sensitivity. The latter test, using a large field and a high luminance level, is particularly sensitive to both the residua of pathology and very early phases of disease, often before subjective manifestations of anomalies are present. These effects are large in patients with demyelinating diseases. Here, we show that such changes may be revealed in optic neuritis due to other causes as well. Note, the same form of response may be detected in more central lesions, but usually in more circumscribed areas of field.

Of a series of 57 formerly amblyopic patients who attained equal visual acuities (20/20 or better in each eye), only 29 were able to alternate after treatment. The oldest patient was 5 years old. The pattern visual-evoked response of the previously amblyopic eye in nonalternators showed a reduced amplitude as compared with that of the sound eye. This probably occurred because of a reduced number of cortical cells subserving the formerly amblyopic eye. Lack of alternation may be the result of cortical competition. More cortical cells are connected to the originally normal eye even after successful treatment of the amblyopic eye in the nonalternating patient.

A rapid visual resolution test conducted on available equipment reveals the presence of rapid falloff in acuity in a case of probable multiple sclerosis. Intense large field illumination was used, and grating acuity was tested using laser red light. The effect is so large that minor anomalies (not subjectively appreciated) or the residuum of earlier minor attacks of retrobulbar optic neuritis can be readily detected. A related "visual fatigue or saturation-like syndrome" was described earlier. In bright environments these patients' vision fades. Briefly closing the eyes restores visual sensitivity. Providing filters or lowering the light level tends to maintain vision. This test must be studied intensively. It offers a noninvasive simple means of showing underlying anomalies in neural conduction of the visual signal. Such anomalies can be prognostic and previously have been revealed only with sophisticated electrophysiological techniques.

Visual acuity was examined in patients successfully treated for strabismic amblyopia, and with equal refractive error in the two eyes (no more of 4 diopters of hyperopia). Patients able to freely alternate fixation showed equal visual acuity in the two eyes without optical correction. An optical correction in front of the ex-amblyopic eye was needed, in order to achieve equal visual acuity in patients unable to freely alternate fixation. No correction was necessary for the sound eye. This difference is attributed to a residual anomaly of accomodation of the ex-amblyopic eye. It is concluded that the concept of cure of strabismic amblyopia based on the attainment of equal visual acuity needs re-evaluation.

Functional amblyopia has been considered as a homogeneous syndrome for the last decade or so, mainly on the basis of animal experiments. Recently, important differences have been shown to exist between strabismic and anisometropic as well as deprivation amblyopia. Even strabismic amblyopia may be subdivided in different classes. These statements are supported with experimental and clinical data. Clinical relevance of the heterogeneity of amblyopia is discussed particularly in the view of the concept of its cure.

Random Dot Stereograms (RDS) are useful, but are sometimes misleading in assessing the degree of binocular cooperation in the presence of aniseikonia. RDS may give positive results up to 15% aniseikonia, whereas a fine central binocularity is not possible with more than 5% image-size difference. It is suggested that stereopsis may not be the only parameter to test; stress is given to the importance of peripheral motor fusion in maintaining the eye alignment.

An automatized computerized deviometer is presented based on an infrared TV camera, an image analyzer and a computer. With this instrument it is possible to follow step-by-step the various diagnostic procedures in strabismus and to answer the following questions: is there a strabismus? is it convergent, divergent or vertical strabismus? what is the angle of deviation? which is the paralytic or paretic muscle in the case of incomitant strabismus?

Vergence movements induced by base-out prisms were recorded, with an infrared eye movement recording system, in 5 patients with comitant esotropia and anomalous retinal correspondence and in 5 normal volunteers. The findings support the hypothesis that vergence movements in strabismus are induced by disparity, since accommodative as well as proximal vergence had been ruled out. Vergence movements are much slower and with different characteristics in strabismic patients with respect to normals. It may be argued that vergence movements represent the motor fusion component left over in strabismus. They may be considered the objective representation of the well-known phenomenon of prism compensation or adaptation, found in many strabismic patients.

In this paper results are presented of errors in spatial localization found after encircling procedures for retinal detachment both in the operated and in the normal eye. Also changes in spatial localization were found in strabismus patients in which a stretch on the operated muscle was exerted after an adjustable recession. In both groups of patients a manipulation of the eye muscle was performed without inducing an eye muscle imbalance in the retinal detachment patients and without modifying the eye position in the strabismus patients in which a stretch was exerted. These data provide further evidence in favour of the role of proprioceptive information in space perception.

It has been demonstrated that, besides sensory adaptation phenomena, sensorimotor phenoma may also develop in concomitant esotropia. The existence of the latter entity can be shown particularly by means of prisms and is interpreted as fusional in origin. It is therefore defined as 'anomalous fusional movements'. The features of these anomalous fusional movements were studied in a group of 30 patients, mainly in order to investigate their finality. Correlations were evaluated between anomalous fusional movements and entities previously described by different names according to the interpretation given them by various authors.

A differentiation of two types of head-turns due to nystagmus, by means of electromyography (EMG) is demonstrated in this paper. The first type is represented by patients who actively block the nystagmus, by means of an increase of discharge of the extraocular muscles who are synergistic and responsible for the head-turn. This block has the same features of the block of nystagmus in convergence and usually exceeds 10-15 degrees from the primary position. The second type is made out of patients whose head-turn is explained with the null-position of Kestenbaum. Here the nystagmus simply disappears in the position of head-turn, which usually is of no more than 10-15 degrees. Both types of patients show the same electronystagmographic features in the position of head-turn. This differentiation is useful from the clinical standpoint. In fact, only the first type of head-turn may require, besides a classical Anderson or Kestenbaum procedure, also a posterior fixation suture according to Cüppers. This operation would be useless in the second type of head-turn. Clinical signs useful for differentiating these two types of head-turn are presented as well.

Disparity-induced vergence movements (fusional movements) were analyzed in esotropic patients by calculating the time required for compensation of a prismatic correction of their angle of deviation. The effect of central and peripheral field stimulation on these movements was studied by masking the central or the peripheral field. Both the center and the periphery were effective in triggering disparity-induced vergence movements. The center even seemed to prevail over the periphery. It is concluded that in comitant esotropia motor fusion is present not only in the periphery but also in the center, if appropriately tested.

The treatment of the infant who is born with sensory deprivation amblyopia is one of the most difficult therapeutic problem sets facing the ophthalmologist today. This group of anomalies has many forms, the most common of which seems to be unilateral and bilateral cataracts. Substantial advances have been made, however, in many aspects of therapy for infants who have this set of problems. We have come to realize that it is essential to address these conditions at the first moment that is consistent with the safety of the child. New techniques in cataract extraction have reduced the time course of surgical treatment, reduced the frequency of secondary cataracts, and sustained the patency of the visual pathway. Unfortunately, practitioners who engage in the surgery may not have the back-up skills in advanced contact lens fitting, correction of aniseikonia, and, in some instances, the strabismological complications which are encountered. Further, improved means of assessment of visual acuity, binocular vision, and other visual characteristics of these infants are only in the developmental stages at this time. Thus, we propose to present the problem in an orderly manner. We shall first review the types of cases and problems. We will then discuss surgical techniques and the information which must be determined during examination under anesthesia (EUA) for the purposes of visual correction. We will then describe the designs of the spectacle lens and/or spectacle/contact lens combinations that are used to correct the resultant aniseikonia and anisometropia. We will address the approaches to patching and techniques on how to best achieve binocular vision in these patients. Separately, means and methods of assessment of vision by preferential looking, visual evoked response, optokinetic nystagmus, and tests of other visual functions will be explored. In summary, we will try to tie together the entire therapeutic regimen that can be used in the treatment of these patients.

Unilateral coronal suture stenosis provokes a shortening of the orbital roof of one side. It is argued that the effectiveness of the superior oblique muscle is reduced because of reduced length of its unreflected part and because of the increased angle between the reflected part of the tendon and ocular axis. This condition causes a clinical picture of superior oblique palsy, with ocular torticollis. We report four cases of this newly described clinical entity with various degrees of involvement of ocular motility.

Simple psychophysical techniques were used in order to assess layer-by-layer retinal functions in a patient with sub-retinal fluid due to a choroidal rupture following ocular trauma. A substained-like and a transient-like function believed to reflect retinal receptive-field-like properties, and an indicator of retinal receptor orientation (the Stiles-Crawford effect) have been followed in time. Central visual acuity was also measured. Initially all measured functions provided anomalous responses in affected retinal areas. Of interest here is the nature and order of recovery of the measured response functions. Most notable was the rapid rate of recovery of receptor orientation and the slower rate of recovery of the transient-like function.

A Castroviejo caliper was modified, adding another caliper to one arm to be able to measure contemporaneously the amount of muscle recession and transposition.

Patients with herpes zoster of the ophthalmic branch of the trigeminal nerve and normal ocular motility were examined. They were asked to point to targets without the sight of their own hand. Significant errors were found on the affected side. Proprioceptive information of the extraocular muscles is assumed to travel in the trigeminal nerve, and these results thus suggest the existence of peripheral afferent signals influencing eye-hand coordination.