The following are the main complications that tattoos may cause: 1. Infection: Tattooing instruments and needles with bacteria can spread infectious diseases such as hepatitis. The risk of infection is that the American Blood Bank Association requires tattooers to wait a year before donating blood. It is very important to ensure that all tattoo equipment is clean and sterile before use. Even if the needle used is sterile or is used for the first time. It is important to understand that in some cases, whether the equipment is needle-loaded or not depends on its design. In addition, the tattooer must take good care of the tattooed part, and can only move normally after finishing the first tattoo or injecting pigment. 2. Removal problem: Although laser technology is advanced, tattoo removal is a labor-intensive process. It may be impossible to completely remove tattoos without leaving scars. 3. Allergic reaction: Although allergic reaction of tattoo pigments is rare. Once it happens, they have some special troubles because these pigments are difficult to remove. Tattooers rarely have allergic reactions, which will last for several years. 4. Granuloma: These are small nodules, which may be formed around foreign bodies in vitro, such as broken wood in tattoo paint. 5, keloid formation: If you are prone to form keloids (scars that grow within normal boundaries), there is a danger of forming keloids after tattoos. Keloid can form at any time when your skin is injured or your spirit is traumatized. 6. Complications of magnetic resonance imaging (MRI): It has been reported that the tattooer or the person with permanent tattoo may have swelling or burns at the tattooed part during MRI. Although this seems to happen rarely, there is no obvious lasting effect. It is also reported that the pigment of tattoo will interfere with the imaging quality to some extent. This situation mainly occurs when permanent eyeliner is examined by magnetic resonance imaging. The causes of these complications are not clear. Some of them are theoretically proved to be caused by the interaction of pigment and metal components used in tattoos. However, the doctor suggested that the risk of not doing magnetic vibration may be greater than the risk of complications caused by the interaction between magnetic vibration and tattoo. On the contrary, for magnetic resonance imaging, those tattooers or permanent tattooers should inform radiologists or physicians of the fact that they have tattooed, so as to take appropriate preventive measures to prevent complications and determine the best treatment effect. The most common problem after tattooing is to get rid of it. Removing tattoos and permanent tattoos will be very difficult. Different people with tattoos have a wide range of different skill levels. You may ask someone to perform a specified procedure for reference, or you may ask yourself and think that you may always carry someone else's mistakes. Even if the tattoo is satisfactory at first, this satisfaction may disappear. Or, if the tattoo artist injects pigments into the skin too deeply, the pigments may move out of their original positions, resulting in blurred images. Another reason for dissatisfaction is that people's bodies are constantly changing, so that the shape of tattoos changes with the seasons. Permanent tattoos look pleasing to the eye after the first injection, and then the tattoos deform with the changes of skin and facial or body contours. People who plan to have facial plastic surgery are generally told that permanent tattoos may be deformed. Tattoos that look fashionable at first will become awkward and unpopular. Changing the appearance of tattoos and permanent tattoos is not as easy as changing your mind. Tattoo removal technology Tattoo removal technology includes: laser treatment, polishing, scratches and surgery. Some people try to cover up old tattoos they don't like with new tattoos. Each method has its disadvantages: 1. Laser treatment can fade most tattoos, and some tattoos can be faded more easily and effectively. Generally speaking, it should be treated every once in a while or every few weeks or months. These treatments may be more expensive. Some people will undercolor the effective area (natural skin color). Laser treatment may also make tattoo pigments become more ideal colors. Unfortunately, the pigments used in tattoos are always difficult to know, and various tattoo inks are becoming more and more complicated. Tattoo ink often only sells brand names, not chemical components. Because these pigments are sold to big customers, rather than retail to consumers, the law does not allow manufacturers to list the ingredients on the labels. Moreover, because manufacturers think that the pigments they sell have patent marks and grades, neither tattoo artists nor consumers can obtain patent ingredients. There are also some case reports: allergic reaction occurs after tattoo removal by laser treatment. The obvious reason is that laser can release allergic substances in tattoo ink into the body, causing allergic reaction. 2, grinding skin is a metal brush or diamond drill (frosted disk). The operation itself will leave scars. 3. Salt rubbing, using salt water solution to remove pigment, sometimes combined with peeling, is used less and less now. 4. Scratch method is a method to remove tattoos with acidic solution, which will form new scars on the original parts. 5. Surgery sometimes includes the application of tissue enlargement. Large areas of tattoos need repeated operations to be completely removed. Masking refers to injecting new pigments to form tattoos with new shapes and covering the old ones.