No abstract

There is a substantial void in the literature of studies that examine the prevalence of non‐strabismic binocular disorders in the population. Using contemporary vergence accommodation criteria this study set out to classify the binocular status of school‐age patients presenting for initial examination in an optometric practice. Seventy‐seven per cent of those presenting had a significant vergence or accommodation disorder on the basis of the stated criteria, and disorders at near made up 90 per cent of the disorders detected. Disorders of accommodation effected 57 per cent of the sample and vergence disorders 58 per cent. Analysis of presenting complaint was not of predictive value in determining whether an anomaly was present, nor was it helpful in predicting which type of anomaly. Hyperopia, astigmatism and anisometropia were however more likely to be associated with a vergence accommodation disorder. Distribution of fixation disparity (FDC) curve types for this clinical population is presented together with some evidence to suggest a distinct sub‐ group within Type 1 responses.

The development of a new screening protocol, The Portsea Modified Clinical Technique (PMCT), is described. This screening technique was designed for use with children in the eight to fourteen years age group and includes such measures as ocular motility, fusional vergence, accommodation, stereopsis and colour vision in addition to the traditional modified clinical test battery. Some six thousand children have been examined using this protocol which requires a screening time of five to six minutes. Referral criteria are given as guidelines only, with the clinician retaining the responsibility for classification on the basis of the whole clinical profile. It is argued that the Orinda MCT criteria can no longer be regarded as inclusive of all the most relevant parameters. Details of the screening administration and instrumentation are outlined.

This paper describes the construction and operation of the Sheedy fixation disparometer and the methods suggested for the analysis of fixation disparity determined by its use.

Visual loss from age related maculopathy (ARM) is thought to involve foveal regions but in this case foveal sparing is reported consistent with a paradoxical performance and symptoms. The fundus view, manifest foveation, better than expected acuity, a blue-yellow colour loss and an intact central visual field support the likelihood of foveal sparing. We suggest that the detection and classification of ARM patients should consider parafoveal integrity by assessing colour vision, contrast sensitivity to medium and low spatial frequencies, and macular perimetry as well as acuity and fundus changes. The prognosis for continued foveal survival greater than four years is poor and patients with foveal sparing should be given a guarded prognosis.