If my 88 year old mother was just diagnosed with hyperglycemia and has blurred vision will her vision improve?

Diabetes and vision. Patients with diabetes mellitus often experience subjective symptoms of blurred vision associated to hyperglycemia. The nature of this phenomenon is not completely clear. Blurred vision during hyperglycemia could be a result of transient refractive alterations due to changes in the lens and in the retina . Macular edema, or retinal thickening can also impair vision in uncontrolled diabetes.