Measuring the refractive properties of the diabetic eye during blurred vision and hyperglycaemia using aberrometry and Scheimpflug imaging

Abstract

The present study suggests that subjective symptoms of blurred vision during hyperglycaemia are not necessarily caused by changes in the refractive properties of the diabetic eye.

Short-Term Stability in Refractive Status Despite Large Fluctuations in Glucose Levels in Diabetes Mellitus Type 1 and 2

“…Although Wiemer et al found no significant changes in the shape of the cornea or lens in 25 diabetic patients after hyperglycemia [37]; nine of their patients showed small but significant hyperopic or myopic shifts. However, in contrast to our study, Weimer et al ’s patients returned for the second visit on another day (average 51 days later) and their results could therefore refer to longer-term rather than true acute ocular changes.…”

“…While our finding of minimal refractive or aberrational change in the presence of normal, modest, diurnal fluctuations in blood sugar level may be typical of such patients, we cannot rule out the possibility that, in a larger population, some individuals may display marked acute changes in either or both blood sugar and refraction. None of our patients complained of blurred vision during the measurement period and it may be that, had our patients been selected on the basis of such complaints, refractive changes might have been observed [37]. A further limitation is the substantial range in age and duration of disease in our diabetic groups, which might be expected to increase the variation across subjects and make subtle changes more difficult to detect: we found it difficult to recruit more homogeneous groups willing to undertake the lengthy set of measurements involved in the study.…”

“…Much of the literature involves patients who have only just commenced treatment [2], [4], [5], [7], [8], [36] or who have recently reported that their vision had become blurred [23], [37].…”

“…Nevertheless the possibility that vision may become degraded in the absence of optical change [37], perhaps due to neural factors, is an interesting one. Further studies in which temporal changes in visual performance, in terms of, e.g., visual acuity or contrast sensitivity, are measured at the same time as blood sugar levels and the optical characteristics of the eye should help to clarify this question.…”

Optical quality of the diabetic eye: a review

“…Although there are few studies that related these changes with the impact on visual quality, 69,70 people with DM undergo variations in blood glucose levels and cause changes in spherical and cylindrical components of refraction, both acute and long term; these changes also known as lower-order aberrations account for approximately 90% of the total ocular aberrations. Although higher-order aberrations (HOAs) make a small contribution (r10%) to the overall wave aberration in the eye, 71 some authors have shown a large effect of degradation in the quality of the retinal image and affect visual acuity.…”