Summary Here we provide confirmation that the ‘ramp retina’ of the horse, once thought to result in head rotating visual behaviour, does not exist. We found a 9% variation in axial length of the eye between the streak region and the dorsal periphery. However, the difference was in the opposite direction to that proposed for the ‘ramp retina’. Furthermore, acuity in the narrow, intense visual streak in the inferior retina is 16.5 cycles per degree compared with 2.7 cycles per degree in the periphery. Therefore, it is improbable that the horse rotates its head to focus onto the peripheral retina. Rather, the horse rotates the nose up high to observe distant objects because binocular overlap is oriented down the nose, with a blind area directly in front of the forehead.

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This study indicates that although Australian optometrists use subjective and objective diagnostic tests and stratify treatment based on dry eye severity, there is a lack of uniformity regarding diagnostic testing, infrequent use of standardized grading scales, and significant variability in clinical care. These findings highlight the potential to improve the translation of dry eye research evidence and evidence-based guidelines into Australian optometric practice.

ObjectiveThe primary aim of this study was to examine the self-reported, routine clinical practice behaviors of Australian optometrists with respect to advice regarding smoking, diet and nutritional supplementation. The study also sought to assess the potential influence of practitioner age, gender, practice location (major city versus regional), therapeutic-endorsement status and personal nutritional supplementation habits upon management practices in these areas.MethodsA survey was electronically distributed to Australian optometrists (n = 4,242). Respondents anonymously provided information about their personal demographics and lifestyle behaviors (i.e., age, gender, practice location, therapeutic-endorsement status, smoking status, nutritional supplement intake) and routine patient management practices with respect to advice across three domains: smoking, diet and nutritional supplementation. Multivariate logistic regression analyses were performed to assess for potential effects of the listed factors on practitioner behavior.ResultsA total of 283 completed surveys were received (completed survey response rate: 6.7%). Fewer than half of respondents indicated routinely asking their patients about smoking status. Younger practitioners were significantly (p < 0.05) less likely to enquire about patients’ smoking behaviors, but this did not extend to counseling for smoking cessation. Almost two-thirds of respondents indicated routinely counseling patients about diet. About half of practitioners specified routinely asking their patients about nutritional supplement intake; this form of questioning was significantly more likely if the respondent was female (p < 0.05). Practitioners who recommended nutritional supplements most commonly did so for age-related macular degeneration (91.2%) and dry eye disease (63.9%). The primary source of evidence used to guide practitioners’ nutrition-related patient management was reported to be peer-reviewed publications.ConclusionsThese findings demonstrate that there are no clear predictors of practitioner behavior across the three domains. Overall, this study suggests that there is scope for Australian optometrists to improve their routine engagement by questioning patients, as well as providing evidence-based clinical advice, about smoking status, diet and nutritional supplement behaviors, being key modifiable lifestyle risk factors with long-term implications for eye health.