The dichoptic-based perceptual learning therapy employed in the present study improved both the monocular VA of the AE and stereofunction, verifying the feasibility of a binocular approach in the treatment of childhood amblyopia.

Background/aims-The study of occlusion eYcacy in amblyopia has been hampered by the use of non-logMAR acuity tests and a failure to assess threshold acuity for both eyes. These issues are addressed in the current study which compares the eVect of spectacles alone and spectacles in combination with occlusion, with the use of the logMAR crowded test. Methods-Changes in uniocular and interocular acuity diVerences were compared for two age matched groups of previously untreated children with strabismic amblyopia: one compliant with spectacles only (n = 17, mean 6.2 (SD 2.5) years) and the other with spectacles and occlusion (n = 69, mean 5.1 (1) years) over a 1 year period. Changes in logMAR acuity were also analysed for a larger occluded group (n = 119) in response to successive 200 hour blocks of occlusion up to >1000 hours, in an attempt to isolate an optimal occlusion regime. Results-Visual acuity improved for more of the amblyopic eyes of the occluded (74%) than the spectacles only group (59%), and only one child from the latter group deteriorated. Mean visual acuity improved for both eyes of both treatment groups, but the change was significantly larger for the strabismic eyes of the occluded group overall and within the first 6 month period (p <0.05). Occlusion was only eVective for the first 400 hours worn. Subsequent visual improvement was bilateral and symmetrical.Conclusion-Occlusion is more eVective in the treatment of strabismic amblyopia than spectacles alone, and the eVect is optimal within the first 6 months of wear. In terms of occlusion duration, maximal improvement occurs in response to 400 hours of occlusion wear or less, and to full time occlusion. Visual maturation continues, but is retarded for amblyopic eyes. (Br J Ophthalmol 2000;84:572-578) Amblyopia aVects 2-3% of the population, and strabismus, often associated with anisometropia, is a major cause.

No abstract

The single fiber needle electrode (SFNE), which is designed to isolate single muscle fiber action potentials, has played an important role in the diagnosis of myasthenia gravis (MG). However, the concentric needle electrode (CNE) has been recently adopted by some workers to study neuromuscular instability in MG, and reference data have also been obtained in healthy subjects. In this study we wanted to establish whether data acquired using the SFNE is comparable to that obtained using the CNE when studying patients with MG. We established reference data for our laboratory using the CNE for orbicularis oculi (OO) and extensor digitorum communis (EDC). We compared data from 24 MG patients using both SFNE and CNE and found no significant differences in mean jitter values for either muscles. We correlated the neurophysiological data obtained by either electrode with various clinical assessments, the ice pack test, OO and EDC strength measurement, and MGFA classification of disease, and we found no significant relation. We compared discomfort scores for the two needle electrodes for each muscle and found that the discomfort scores for CNE are significantly lower (P = 0.0004). We conclude that the CNE is a useful alternative electrode for studying single fiber potentials, but more reference data from normal control subjects is desirable. Muscle Nerve, 2008.

This is the first detailed analysis of EOM involvement in ocular myasthenia. The EOM weaknesses for the control group were invariably bilateral and symmetrical, mainly involving the superior recti. The preponderance for involvement of the elevator muscles is discussed.

Orthoptic exercises are an effective means of reducing symptoms in patients with convergence insufficiency and decompensating exophoria, and appear to target the proximal and fusional components of convergence. Their role in esophoria is unclear and needs further study.

The findings confirm that ocular motility problems are not exclusive to scleral buckling, with the incidence being similar in both groups. Slinging of the extraocular muscles and the accompanying dissection, resulting in the 'fat adherence syndrome', must be considered as contributory factors. The visual deficits which inevitably occur as the result of retinal detachment seem to play a more major role in the disruption of binocularity in these cases.

Aims/background-The basis of binocular single vision in microtropia remains a matter of contention. This paper discusses the implications of recovery, in a group of primary microtropes following treatment, in relation to current concepts on the aetiology of the condition and proposed retinocortical correspondence. Methods-Nine previously untreated primary microtropes whose condition resolved, were reviewed in detail to assess the patterns of change in retinal correspondence, uniocular fixation, stereoacuity, and visual acuity in response to treatment. Results-Anomalous retinal correspondence (ARC), a central scotoma, reduced or absent stereoacuity, amblyopia, and uniocular eccentric fixation were present in all patients before treatment. Following treatment, all cases attained normal retinal correspondence (NRC), elimination of the central scotoma, stereo acuity levels of between 20 and 40 seconds of arc, 6/5 Snellen visual acuity in both eyes, and foveal fixation in both eyes. Conclusion-A hypothesis is put forward that for the patients described, a period of normal development is likely to have preceded the onset of microtropia, during which the retinocortical "foundations" for NRC were established. Precise pairing of foveo-foveal receptive fields was not abolished by the presence of amblyopia and a central scotoma, but this relation was temporarily suspended and binocular single vision was sustained via the neural substrate of paired receptive fields over a wide retinocortical area. (Br J Ophthalmol 1998;82:225-231) Microtropia, first described by Lang, 1 is a unique form of small angled strabismus with a highly developed degree of binocular cooperation compared with other forms of heterotropia, but stereoacuity is invariably reduced or absent with particularly poor responses demonstrated to random dot stereo tests.2 3 Microtropia can be classified as being "with" or "without identity" 2 according to the cover test findings. The term "identity" refers to the relation between the binocular angle of anomaly of anomalous retinal correspondence (ARC) and the uniocular angle of eccentric fixation: where these are coincident there is no movement on the cover-uncover test, as the same retinal area is stimulated uniocularly and binocularly. The microtropia is said to be without identity when the angle of anomaly exceeds the angle of eccentricity, so a manifest movement is seen on cover test. Primary microtropia is considered essentially sensorial in origin, unlike other forms of strabismus in which suppression and ARC develop in response to a motor anomaly in order to avoid diplopia and confusion. Proposed aetiological factors include an inherent inability or loss of ability for bifoveal fusion, 4-6 anisometropia producing a habitually defocused image in one eye and a subsequent foveal scotoma, 7 a "statistical variant" in the fixation reflex feedback mechanism, 2 8 and a genetic/hereditary component with a particular familial disposition to ARC. 9 10This paper appraises the clinical features before and af...