Popular Science Interpretation - "Expert Consensus on Multifocal Soft Lens Fitting for Myopia Control (2023)"

As one of the effective means to control myopia in children and adolescents, multifocal soft lenses have been known and accepted by more and more parents since entering the domestic market in 2022.

Regarding the clinical fitting of multifocal soft lenses, experts from professional organizations such as the Optometry Group of the Ophthalmology Branch of the Chinese Medical Association, the Optometry Committee of the Ophthalmology Branch of the Chinese Medical Association, and the Optometry Group of the Ophthalmology Committee of the Chinese Association of Non-public Medical Institutions have compiled the "Expert Consensus on the Fitting of Multifocal Soft Lenses for Myopia Control (2023)" and published it in the "Chinese Journal of Optometry and Visual Science".

Like other clinical guidelines and consensuses, this consensus is also a professional discussion for ophthalmology and optometry practitioners to read and refer to. Dr. Jingcai tries to explain the consensus content in a popular way for parents to refer to.

What are multifocal soft lenses?

Multifocal soft lenses are one of the most effective means of preventing and controlling myopia. They look almost the same as ordinary contact lenses.

but:

- Ordinary contact lenses can only correct myopia, but cannot delay the progression of myopia;

-The design of multifocal soft lenses is based on the "optical defocus theory": light passes through the "correction zone" and focuses on the retina to form a clear focus; light passes through the "treatment zone" and focuses in front of the retina to form peripheral myopic defocus, thereby achieving the purpose of delaying the progression of myopia and increasing the length of the eye axis.

Dr. Jingcai has simply compiled the table below to compare the characteristics of ordinary contact lenses and multifocal soft lenses for your reference. The two are completely different in terms of purpose of use, lens design, etc., so don't confuse them.

How long has multifocal soft lenses been used to control myopia?

In foreign countries, multifocal soft lenses have been used for myopia control for several years. In 2021, in the US market, multifocal soft lenses accounted for 72% of contact lenses used for myopia control. The International Myopia Research Institute (IMI)'s "White Paper of the International Myopia Research Institute", the Asian Optometry Association (AOMA)'s "Asia Myopia Management Consensus", and China's "Myopia Management White Paper (2022)" all list multifocal soft lenses as one of the effective means of myopia control.

How effective are multifocal soft lenses in controlling myopia?

At present, there are two designs of multifocal soft lenses commonly used in clinical practice: concentric bifocal and progressive multifocal. Dr. Jingcai will not introduce them in detail. The research of Li et al. showed that both multifocal soft lenses with different designs have good myopia control effects and can delay the progression of myopia refraction by 25% to 50% in 2 years. Even if it is used in adolescence, it is still effective. The consensus also lists a large amount of clinical research data, which will not be introduced in detail here.

In what situations can you consider wearing multifocal soft lenses to control myopia?

(1) Myopic patients who want to control myopia:

① Children and adolescents whose myopia increases by 50 degrees or more each year, or whose eye axis increases by 0.4 mm or more;

② Pathological changes of the fundus caused by axial length growth;

③ Patients with high-risk factors for myopia and/or high myopia, including parents with a history of myopia, less time spent outdoors, long time using eyes at close range, myopia in early school age (7 years old and below), and higher myopia than children of the same age;

(2) In addition to refractive error, there are no other eye or systemic diseases that affect the wearing of soft lenses;

(3) The environment and sanitary conditions can meet the requirements for wearing soft lenses;

(4) Able to follow doctor's orders, have good compliance, and go to medical institutions for follow-up visits in a timely and regular manner as required;

In what situations is it not suitable to wear multifocal soft lenses?

(1) Eye problems: any acute inflammation of the eye, chronic keratitis, chronic uveitis, chronic dacryocystitis, chronic limbalitis, moderate or severe dry eyes, keratoconus or irregular cornea; corneal endothelial cell density less than 2,000 cells/square millimeter; lens opacity and glaucoma that affect vision;

(2) Other diseases: patients with acute and chronic sinusitis, severe diabetes, rheumatoid arthritis and other collagen diseases and mental illnesses;

(3) Individual conditions: poor personal hygiene, poor compliance, and inability to undergo regular checkups;

(4) Those who are allergic to lens materials or care systems;

(5) Poor living environment, such as long-term exposure to smoke, dust, acidic or alkaline dust and mist, etc.

(6) Other conditions that the physician considers to affect the wearing of multifocal soft lenses;

Is it safe to use multifocal soft lenses to control myopia?

Dr. Jingcai emphasized that multifocal soft lenses need to be fitted in regular medical institutions and used in a standardized manner under the guidance of a physician. This is a prerequisite for safety. The consensus lists some research data, which shows that the overall safety of multifocal soft lenses for myopia prevention and control is still quite high, for your reference:

A study by Chalmers et al. showed that the probability of infectious keratitis in children wearing soft lenses is approximately 7.4/10,000 wearing years, which is lower than the 57/10,000 wearing years reported by Holden et al. for adults wearing long-wear soft lenses; in a long-term follow-up study on the safety of children wearing bifocal soft lenses by Wood et al., the incidence of corneal infiltration events in children was 6.1/1,000 wearing years, and 99% were mild manifestations of grade 1 or below.

Dr. Jingcai’s summary: Multifocal soft lens products have only recently entered China, but are widely used internationally. They are generally recognized by ophthalmology and optometry professional groups at home and abroad, and there are many high-quality research results to support their effectiveness and safety. Parents can choose for their children after consulting professional doctors as needed.

If you find this article helpful, you are welcome to share it with more parents. While helping them, you are also helping us. Thank you.
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