Diabetes can cause many eye diseases, such as diabetic retinopathy, cataract, glaucoma, diabetic optic neuropathy, etc. Among them, diabetic cataract is one of the common complications. According to statistics, the chance of developing diabetic cataract among diabetic patients is 60% to 65%.
The lens inside the eye will become more and more cloudy as a person ages, thus causing vision loss or even blindness, which is what we usually call senile cataract. Under normal circumstances, the lens absorbs nutrients from the eye through a cellular membrane, eliminates metabolic products, and maintains nutritional balance. When suffering from diabetes, the long-term chronic increase in blood sugar causes the lens to accumulate too much glucose, which can be converted into sorbitol and fructose by special enzymes, causing the osmotic pressure in the lens to rise, which means that the lens absorbs water and swells, and the anabolic process of the lens such as protein is disturbed, which eventually leads to lens clouding and causes cataracts over time.
Diabetic cataracts can be divided into two types: true diabetic cataracts and combined senile cataracts. True diabetic cataracts are rare and often occur before the age of 30 in patients with severe type 1 diabetes. The clinical manifestations of combined senile cataracts are very similar to those of senile cataracts without diabetes, except that they occur earlier, progress more rapidly, and mature easily.
True diabetic cataracts mostly occur in type 1 juvenile diabetics before the age of 30. Both eyes may develop simultaneously, developing complete clouding of the lens and significant vision loss within a few days. This type of cataract can slowly or even stop progressing as blood sugar is controlled and systemic condition improves.
Combined senile cataracts, on the other hand, occur mostly in diabetic patients over 45 years of age. Senile cataracts coexist with diabetic cataracts, but develop more rapidly than senile cataracts and can develop in a single eye first. The clinical presentation of senile cataract in diabetic patients is basically the same as that of senile cataract in non-diabetic patients, mainly slow progressive blurred vision and vision loss, but it develops at a younger average age and progresses to maturity more rapidly.
Since the pathogenesis of diabetic cataract is mainly related to elevated blood glucose, active blood glucose control is the first principle. The next step is to adopt a reasonable treatment plan according to the degree of cataract. In the early stage, medication is the main treatment. The most applied cataract drugs include antioxidants and crystal protein protectors, but the treatment effect is not obvious.
The near-mature stage and mature stage of cataract should receive surgical treatment. Cataract ultrasound emulsification combined with IOL implantation is the preferred surgical procedure due to its advantages of small surgical incision, light injury, few complications and fast postoperative recovery. For patients with diabetic cataract who have already developed diabetic retinopathy, as distinguished from patients with senile cataract, a consultation with a fundoplication surgeon should be requested in a timely manner, a thorough plan should be made, and diabetic retinopathy should be treated in a timely manner after surgical cataract removal to control the development of retinopathy.
Otherwise, some patients with diabetic cataract will have a drastic loss of vision after surgical cataract removal due to the complication or aggravation of diabetic macular edema.