Doctor, is my cataract “ripe”?

Author: Yang Tianke Fudan University Affiliated Eye, Ear, Nose and Throat Hospital

Reviewer: Luo Yi, Chief Physician, Eye, Ear, Nose and Throat Hospital, Fudan University

Cataract is a common eye disease. Many middle-aged and elderly people have these questions after they seek medical treatment due to decreased vision or are diagnosed with cataracts through health screening:

"Doctor, my vision is so-so, but I can still see clearly. Wouldn't it be better to wait until the cataract is 'ripe' before surgery?"

"Doctor, I don't feel my eyesight has deteriorated. Do I have to get rid of the cataract now?"

"Doctor, I don't want to have cataract surgery now. Will I go blind if I wait any longer?"

Today we are going to talk about age-related cataracts (senile cataracts).

1. What is cataract?

Cataract is a type of eye disease characterized by clouding of the lens. It is one of the major causes of blindness in the world, and the most common type is age-related cataract. Age-related cataract usually occurs in middle-aged and elderly people over 50 years old, and the incidence rate increases with age.

If the eye is compared to a sophisticated "camera", then the transparent lens is the "lens" responsible for focusing. Factors such as age, ultraviolet radiation and malnutrition can cause the lens to become less transparent and cloudy, which is equivalent to a blurred "lens", thus causing a decline in visual quality.

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2. Age-related cataracts: “mature” and “unmature” – staging and grading

1. Stages of age-related cataract

According to the development process of the disease, age-related cataracts can be divided into the initial stage, immature stage, mature stage and over-mature stage. The development of lens opacity is like the process of raw eggs becoming cooked eggs, and the "ripe" cataracts often mentioned by middle-aged and elderly people are usually in the mature stage or even over-mature stage of cataracts.

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2. Lens Opacity Classification System III (LOCS III)

At present, the LOCS Ⅲ system is commonly used in clinical practice to classify and evaluate lens opacities observed under a slit lamp microscope. In short, according to the location of the lens opacity, the lens nuclear opacity (N), cortical opacity (C), posterior subcapsular opacity (P) and lens nuclear color (NC) are divided into standard grades to evaluate the degree of lens opacity.

3. Grading of lens nuclear hardness

The commonly used clinical grading of lens nucleus hardness adopts the Emery grading method which uses a slit lamp to examine the color of the lens nucleus: Grade I, the lens is like jelly; Grade II, the hardness of the lens nucleus is similar to tofu; Grade III, the hardness of the lens nucleus is like chestnut; Grade IV, the hardness of the lens nucleus is like soap; Grade V, the lens nucleus is as hard as plastic.

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3. Should cataracts be left to mature? When to have surgery

Surgery is currently the only effective way to treat cataracts. So, what criteria need to be met to undergo cataract surgery?

In the past, the concept was to have cataracts “fully cured” before surgery. However, with the advancement of medical technology and people’s desire for a healthy life, the requirements for cataract surgery have changed from being able to see after surgery to not only seeing clearly (full vision) but also seeing comfortably and lastingly. Therefore, cataract surgery can be considered in the following situations, provided contraindications are excluded:

1. Vision and visual function cannot meet daily needs, and cataract surgery may improve visual quality;

2. Angle-closure glaucoma caused by inflammation of the lens (lentolysis), anterior chamber angle closure, and uncontrolled drug therapy;

3. Lens opacity hinders the diagnosis and treatment of retinal fundus diseases.

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It should be noted that if cataracts are left to mature without timely treatment, it will not only increase the probability of eye complications such as glaucoma and uveitis, but will also significantly increase the difficulty of surgery and thus prolong the postoperative recovery time. At the same time, "mature" cataracts can cause blindness, seriously affect daily life, increase the risk of falls, and increase the burden on families and society.

Finally, I would like to remind our middle-aged and elderly friends that cataracts must be detected early, diagnosed early, and treated in a timely manner so that they can regain a clear vision as soon as possible and enjoy a better life.