How should beginners choose contact lenses？Daily, Monthly, or Annual?

How should beginners choose contact lenses？Daily, Monthly, or Annual?

So simple, the wearing cycle of contact lenses is divided into traditional type (traditional), frequent replacement type (frequent replacement) and disposable type (disposable). 

For the public understanding, traditional type corresponds to: annual, half-yearly, frequent replacement type corresponds to: monthly, biweekly throwaway: before daily throws, many people classify monthly and biweekly throws as throwaways, and this classification is not scientific , the correct division method should be in accordance with the above classification. 

In short, if you can buy a disposable type, you can buy a disposable type. If you can’t buy a disposable type, you can buy bi-weekly or monthly. Unless you have to buy semi-annual and annual, such as special prescriptions, special customized lenses (special beauty films), otherwise Don't buy traditional products.

The purpose of eliminating annual and semi-annual throws is to find that the complications of contact lenses are mainly caused by two problems:If the oxygen permeability of invisible materials is low, it will lead to corneal hypoxia, edema and other problems. Long-term wear leads to increased deposits on the lens surface, leading to infection, etc.

There are so many problems caused by contact lenses. High oxygen permeability materials can solve the problems of corneal hypoxia and edema to a certain extent, but they still cannot solve the problems caused by precipitation. Therefore, for safety, short-cycle products are combined with high Oxygen permeable material is the perfect combination at present. Therefore, from a safety point of view, we strongly recommend that you use short-cycle silicone hydrogel products. The recommendation level is from top to bottom: Silicon Hydrogel Daily Disposal Silicon Hydrogel Bi-weekly Silicon Hydrogel Monthly Disposal Hydrogel Day Throwing hydrogel biweekly throwing hydrogel monthly throwing quarterly throwing - half a year throwing - annual throwing, non-special circumstances are not recommended. Special cases are: special material lenses, special purpose lenses, height lenses exceeding ordinary custom prescriptions, etc.

Many people say that the annual throw can be worn for one year, the half-year throw can be worn for half a year, and the daily throw can be worn for one day.

Okay, let's talk about the material first:

PMMA - contact lens lenses from a long time ago are popular all over the world because of their easy manufacture, durability, and good optical performance with variable parameters, but their shortcomings are also very prominent, poor oxygen permeability, which directly leads to corneal hypoxia, including the current RGP. On this basis, it is developed by adding various breathable materials. 

HEMA-the material developed in the 1950s is characterized by softness and good comfort. It can be said that most soft hydrogel lenses will use HEMA, the most basic water-absorbing monomer, and then add other monomers to achieve Increase product hardness, improve wettability, settling resistance and increase or decrease moisture content. Different manufacturers will use contact lens materials composed of different polymers, monomers, and polymers, and then name them different materials, and then different manufacturers and materials will have different product names, such as Both Weikang and Bausch & Lomb used polymacon, and Bausch & Lomb called Qinglang (half a year) air thin for half a year, Weikang called Shuiying, X-blue, etc. But the problem with HEMA is that all oxygen permeability depends on water. The more water, the more oxygen permeable The higher it is, the easier it is to dry the eyes and the more precipitation, the less water and the poorer oxygen permeability. It is really difficult to deal with. Then there is the current mainstream silicon hydrogel (silicone), which is the material with the highest oxygen permeability at present, and it also represents The highest production process for soft lenses is currently being done by several major manufacturers. Due to the particularity of materials and the safety of wearing lenses, only daily, bi-weekly and monthly disposables are produced. 

 

Another thing that many people are concerned about, isn't there a non-ionic material? This thing is the concept of speculation, you go to see which manufacturer does not have non-ionic materials? Who came up with the hype and said it was a new material? It's not that the pupils are awesome. I feel that I have everything in seconds, and I have come up with a schematic diagram of what non-ionics are better than silicone hydrogels and hydrogels. I really don't want Bilian. Non-ionic materials are just one type of hydrogel, not a new category.

As for the processing technology, the stable molding method is basically the main method. Because of its high efficiency and low cost, most soft mirrors use this process.

Generally, there are three types of processes: hard and well-shaped lenses, suitable for novices, mostly used to correct astigmatism and part of annual polishing, which have been replaced by molding, and are currently mostly used for astigmatism production.

The annual throw is indeed high in hardness, but it has many disadvantages. Although the positioning is long-term, it will not take long to lead to lens contamination due to various precipitations. Once it causes harm to the eyes, there will be no regrets~ Therefore, we It is not simply looking at the lens material, the lens technology determines the quality of the lens, but considers this issue from the comprehensive health of the eye. Therefore, daily disposables, whether it is hydrogel or silicone hydrogel, are good for daily disposables~!

Thanks for reading 

Sophie Yang

004@mikeeyewear.com