How Does Diabetes Affect Eyesight?

In this article, we will explain the effects of diabetes on the eyes. In the second half, we will explain how to treat diabetic retinopathy, so please read to the end.

Table of Contents

• Effects of diabetes on the eyes

• How vision deteriorates with diabetes What is diabetic retinopathy? 

• What Characteristics and causes of diabetic retinopathy? What Treatment methods for diabetic retinopathy?

•  Preventive measures for diabetic retinopathy Early detection of diabetic retinopathy is crucial

 Effects of diabetes on the eyes

Diabetes can cause various eye complications, including blockage of capillaries in the retina, and peripheral neuropathy and metabolic disorders due to hyperglycemia.

Some complications may not cause any noticeable symptoms in the early stages, and diabetic patients with peripheral neuropathy may not feel pain, so caution is required.

Be aware that having diabetes can cause eye problems.

How diabetes can cause vision loss

The mechanisms by which vision declines due to diabetes are "clouding of the transparent tissue of the eye" and "destruction of the retina, the nerve that senses light."

Causes of reduced eye transparency include cataracts, which cloud the lens, and bullous keratopathy, which clouds the cornea. Additionally, if bleeding occurs in the vitreous and blood accumulates, the vitreous becomes cloudy, impairing vision.

On the other hand, causes of loss of function of the retina, which is the nerve that senses light, include retinal detachment and neovascular glaucoma (the two main direct causes of blindness due to diabetes).
Both conditions are caused by diabetic retinopathy, a condition in which the blood vessels of the retina are damaged by diabetes.

What is diabetic retinopathy?

Diabetic retinopathy is a diabetes-induced condition that damages the retina, a tissue in the eye, leading to diminished vision.

It is said to be one of the three major complications of diabetes, along with diabetic nephropathy and diabetic neuropathy.

Similar to other diabetic complications, diabetic retinopathy often doesn't present noticeable symptoms in its early stages.

If left untreated, the condition can deteriorate, causing various visual impairments and eventually leading to blindness.

 What is the retina?

The retina is an organ that detects the brightness and color of the light that enters through the pupil and is very important for seeing things.

Retinopathy is a disease in which the retina becomes damaged for some reason, resulting in a condition similar to that of a camera, in which the sensitivity of the film decreases or the film itself becomes damaged.

To varying degrees, diabetes patientsAbout one third is said that retinopathy is occurring in these cases.

Stages of diabetic retinopathy
 Diabetic retinopathy is broadly classified into three stages based on the degree of progression.

[Stage 1 of diabetic retinopathy] Simple diabetic retinopathy

This is the early stage of diabetic retinopathy. The first abnormalities to appear are aneurysms caused by swelling in the walls of small blood vessels and small hemorrhages.

Proteins and fats can leak out of blood vessels and form spots (hard exudates) on the retina.

However, these symptoms may improve if blood sugar levels are better controlled.
 [Stage 2 of diabetic retinopathy] Preproliferative diabetic retinopathy

Preproliferative diabetic retinopathy is a step more advanced than simple retinopathy.

When small retinal blood vessels become blocked over a wide area, the retina does not receive enough oxygen, and the body begins to prepare to create new blood vessels (neovascularization) to supply the missing oxygen.

At this time of year, many people notice symptoms such as blurred vision, but sometimes they may not have any symptoms at all.
 
[Stage 3 of diabetic retinopathy] Proliferative diabetic retinopathy
Proliferative diabetic retinopathy is a severe form of diabetic retinopathy.
New blood vessels grow toward the retina and vitreous humor.

The new blood vessels are prone to rupture and may bleed into the retina or vitreous.

If bleeding occurs in the vitreous, even if the amount is small, it can cause floaters, which are black shadows or specks that appear in your field of vision.

If the amount of bleeding is large, vision will decrease. It is said that bleeding into the vitreous humor often results in vision that looks like ink being poured out.

If bleeding continues repeatedly or periods of poor condition continue, a fibrous membrane called proliferative tissue may appear, which can lead to retinal detachment.

Characteristics and causes of diabetic retinopathy

 When you have diabetes, your cells are unable to properly absorb sugar from your blood.

If there is a lot of sugar in the blood for a long time, the sugar will eventually start to damage the blood vessels.

The blood vessels in the retina of the eye are thin and therefore particularly susceptible to damage, causing them to become clogged or bleed.

When existing blood vessels are damaged and no longer function, they are no longer able to deliver nutrients, so new blood vessels (neovascularization) are created. These blood vessels are very fragile and frequently suffer from bleeding and leakage of nutrients.

This condition can manifest symptoms such as blurred vision and reduced visual acuity.

As the disease advances, it can result in complications such as retinal detachment and glaucoma, both of which have the potential to cause blindness.

Treatment for diabetic retinopathy
There are two types of treatment for diabetic retinopathy: medical treatment and surgical treatment.

Treatment approaches diverge according to the stage of progression, emphasizing that initiating treatment sooner is not only less invasive but also significantly boosts the likelihood of averting vision impairment or blindness.

Diabetic retinopathy is a disease that cannot be completely cured.
Therefore, treatment is given to prevent the symptoms from worsening. Please see below for specific treatment methods.

 Treatment for diabetic retinopathy [1] Early stage
In the early stages, medical treatment is provided, such as blood sugar control and treatment of high blood pressure.

 Treatment for diabetic retinopathy 2 Mid-stage

To prevent the development of new blood vessels, a procedure called "laser photocoagulation" is performed, in which the fundus is cauterized with a laser.

 Laser photocoagulation
Laser photocoagulation is a treatment that stops the progression of the disease by irradiating the affected area of ​​the retina and the fundus (the back of the eyeball) with a laser beam to burn and harden the affected area.

Although this treatment cannot improve vision, it is considered to be extremely effective, particularly for various diseases that occur in the retina, in that it prevents the disease from worsening while maintaining current vision to a greater extent than usual.

Treatment for diabetic retinopathy 3 Late stage

If diabetic retinopathy progresses to the point where retinal detachment or vitreous hemorrhage occurs, vitreous surgery is performed.

Vitrectomy

Vitrectomy is a procedure to remove tissue from the eye called the vitreous humor and treat diseases of the vitreous and retina.

It is classified as a very delicate and difficult surgery.

The key to preventing diabetic retinopathy is regular check-ups.
Many people feel relieved once they have been tested and found to have no abnormalities, but this is not the right thing to do.

Diabetes is associated with many eye diseases, including glaucoma, cataracts, and retinopathy.

So, have your eyes checked every year.
In addition, to preventing diabetic retinopathy, it is also important to pay attention to your blood sugar, blood pressure, and cholesterol.
 
Blood sugar

HbA1c, which reflects the average blood sugar level over 1-2 months and is an indicator of blood sugar control, is Less than 7.0% (aim for less than 6.0% if possible).
 
Blood Pressure

The blood pressure reduction goal for diabetic patients is 130/80 mmHg. So, home blood pressure is 125/75 mmHg. It is as follows:.

People with diabetes often also have high blood pressure.

If both conditions occur together, the risk of heart disease, stroke, kidney disease, etc. increases, so active blood pressure control is important.
 
Cholesterol

The current guideline for the management of blood lipids in diabetic patients is LDL cholesterol.< 120 mg/dL(less than 100 mg/dl if you have coronary artery disease), HDL cholesterol40 mg/dL or higher, neutral fat< 150 mg/dLis.
 
Early detection of diabetic retinopathy is crucial

Diabetic retinopathy progresses without any noticeable symptoms.
By the time symptoms become noticeable, the condition has progressed quite far and patients must prepare for blindness.

Therefore, if you are diagnosed with diabetes or are at risk of developing it, control your blood sugar as instructed by your doctor and have regular fundus examinations with an ophthalmologist, even if you have no symptoms.

One of the indicators of diabetes is hemoglobin A1c (HbA1c...normal value is 4.3 to 5.8), and it is said that if this value is 7.5 or above, the risk of going blind increases by more than five times.