Changes in refraction caused by induction of acute hyperglycemia in healthy volunteers

Purpose: To determine whether the myopic changes and ocular hypotension aft er a glucose load are caused by hyperglycemia. Methods: Oral glucose tolerance tests were conducted on seven healthy young subjects with normal vision. The changes in the hematologic parameters and the refractive system were measured periodically for 150 minutes after the glucose load. Results: After the glucose load, there was an increase in plasma glucose le vel and the level of plasma osmosis, ocular hypotension, a myopic change in refractive power, shallowing of the anterior chamber, and a thickening of the lens. The degree of the myopic change exceeded the power of the residua l accommodation. Normalization of the plasma glucose level led to a normali zation of the intraocular pressure and a reversal of the myopic changes. Conclusions: These findings suggest that the myopic changes that accompanie d hyperglycemia were caused by a thickening of the lens resulting from a de crease in the tension of the zonule fibers of Zinn, and were secondary to o cular hypotension. Hyperopia appealed to be caused by the reversal of the m yopia after normalization of plasma glucose levels. (C) 1999 Japanese Ophth almological Society.