Clinical Observation Of 755nm Picosecond Laser, 1064 Q-switched Laser Combined With Micro-needle Introduction Of Tranexamic Acid To Treat Chloasma

The First Part:The Clinical Obserwation Of 755nm Picosecond Laser Treatment Of ChloasmaThe mechanism for laser therapy is mostly based on selective photothermolysis,and Q switch laser can selectively act on target substrate(melanin)of a pigmented skin lesion.Since the pulse width of Q switch laser is extremely narrow,it can have a blasting effect on melanin granules,thus realizing the function of removing freckle.The laser equipment used to treat pigmentosus diseases needs to have the following characteristics:narrow pulse width,strong mechanical blasting effect and little thermal damage.Picosecond laser has ultra short pulse width,so it can make more energy distributed within the time of thermal relaxation and decrease the energy density,thus significantly reducing the thermal damage of surrounding tissues and lowering the occurrence probability of pigmentation.It has a better therapeutic effect than traditional Q switch lasers in the treatment of chloasma.Objective:To observe the clinical efficacy and adverse effects of the 755nm picosecond laser to treat melasma.Methods:Total 52 outpatients with melasma in our hospital during December 2015 to December 2016 were randomly selected for treatment with 755nm picosecond laser.These patients were treated once every 7 weeks,3-4 times as a course.The average area of melasma and severity index scores were calculated respectively before and after treatment.The adverse effects and patient satisfaction survey were recorded at the same time.Then statistical analysis was performed.Results:52 cases of chloasma patients after 2-4 treatment,chloasma patients had different degrees of improvement,12 cases improvement rate reached more than 60%and more than 50%of the 32 cases improved and The effective rate was 82.7%.No serious adverse reactions occurred in the patients,and the effect of improving the texture of the skin,more than 90%of patients expressed satisfaction.Conclusion:the application effect of the picosecond laser treatment is better,and it has the value of popularization and popularization in clinic.The second Part:Clinical Observation of Microneedle Importing Tranexamic Acid into Skin Combined with Q Switch 1064nm Laser for Treating ChloasmaThe theory of Q switch 1064nm laser used to treat chloasma is mainly based on selective photothermolysis.As the pulse width of the laser can be shortened to 5-10ns,it’ s able to smash the melanin granules into very small particles,and then they are eliminated by macrophages with no damages to surrounding healthy skin tissues.However,when the target tissue doesn,t absorb enough energy and undergoe an insufficient blasting effect,the increase of the energy may cause damages to surrounding skin tissues.Therefore,some patients may experience side effects such as pigment aggravation and post inflammatory pigmentation(PIH)when using Nd:YAG laser to treat chloasma in clinic.Tranexamic acid has a good curative effect on chloasma,and there are many explanations for its mechanism.For example,plasmin has an activating effect on the proliferation of melanocyte or the melanogenesis,while tranexamic acid may inhibit this effect.In addition,tyrosine and tyrosinase are needed in the generation of melanin,while tranexamic acid has a chemical structure similar to that of tyrosine,both of which have a carboxyl group(-COOH),so it may compete with tyrosine for tyrosinase and thus inhibit the catalytic action of tyrosinase on tyrosine,thereby reducing the generation of melanin.Although the oral administration of tranexamic acid is effective,it takes too much time and patients are hard to keep taking it.Moreover,female patients may worry about the decrease of menstrual quantity.These side reactions can be effectively avoided through microneedle importing tranexamic acid into skin.Furthermore,microneedle importing tranexamic acid into skin can combine with the Q switch laser in the treatment of chloasma,which can effectively shorten the treatment time and reduce the side reactions.Objective:To observe the clinical efficacy and adverse reactions of microneedle importing tranexamic acid into skin combined with Q Switch 1064nm laser to treat chloasma.Methods:94 patients with chloasma were randomly selected from department of dermatology in our hospital during April 2014 to April 2015,and these patients were divided into two groups:the control group was treated by only Q switch 1064nm laser,twice per a month,for 6 times,a total of 62 patients(n=62);the observation group were treated by combined method including microneedle importing tranexamic acid into skin for 4 times,twice per a month,and then used Q switch 1064nm laser treatment for 6 times,a total of 32 patients(n=32).The average area of melasma and severity index scores were calculated respectively before and after treatment.The adverse effects and patient satisfaction survey were recorded at the same time.Results:The effective rate in observation group was 96.88%,compared with 81.25%in the control group.The observation group was significantly better than the control group.The adverse reactions in the observation group were significantly less than the control group,and the patient’s satisfaction was higher in the observation group than in the control group.Conclusion:Microneedle importing tranexamic acid into skin combined with Q Switch 1064nm is effective in the treatment of chloasma,and it has the value of popularization in clinic.