Chloasma ndi vuto lomwe anthu ambiri amapeza pakhungu pochita zachipatala. Nthawi zambiri zimachitika mwa amayi omwe ali ndi zaka zobereka, ndipo amatha kuwonedwanso mwa amuna osadziwika bwino. Iwo yodziwika ndi symmetrical pigmentation pa masaya, pamphumi ndi masaya, makamaka mu mawonekedwe a gulugufe mapiko. Wopepuka wachikasu kapena wofiirira, wolemera wakuda wakuda kapena wakuda wopepuka.
Pafupifupi mitundu yonse ndi mafuko ang'onoang'ono amatha kudwala matendawa, koma madera omwe amakhudzidwa kwambiri ndi UV, monga Latin America, Asia, ndi Africa, ali ndi vuto lalikulu. Ambiri mwa odwala amakhala ndi matenda m'zaka zawo za 30 ndi 40, ndipo zochitika za 40- ndi 50 zaka ndi 14% ndi 16%, motero. Anthu akhungu amakula msanga, ndipo akhungu amakula pambuyo pake, ngakhale atasiya kusamba. Kafukufuku wochokera kwa anthu ochepa ku Latin America akuwonetsa zochitika za 4% mpaka 10%, 50% mwa amayi apakati ndi 10% mwa amuna.
Malinga ndi malo omwe amagawira, melasma ikhoza kugawidwa m'magulu atatu azachipatala, kuphatikizapo pakati pa nkhope (kuphatikizapo mphumi, mphuno, masaya, etc.), zygomatic ndi mandible, ndipo chiwerengero cha zochitika ndi 65%, 20. %, ndi 15%, motero. Kuphatikiza apo, matenda ena a pakhungu, monga idiopathic periorbital skin pigmentation, amaganiziridwa kuti amalumikizidwa ndi melasma. Malinga ndi malo a melanin pakhungu, melasma imatha kugawidwa m'magulu amtundu wa epidermal, dermal ndi osakanikirana, omwe mtundu wa epidermal ndi wofala kwambiri, ndipo mtundu wosakanikirana ndiwotheka kwambiri.Nyali ya Woodndizothandiza pakuzindikiritsa mitundu yazachipatala. Pakati pawo, mtundu wa epidermal ndi wofiirira pansi pa kuwala kwa Wood; mtundu wa dermal ndi imvi kapena buluu wowala pansi pa maso, ndipo kusiyana sikukuwonekera pansi pa kuwala kwa Wood. Magulu olondola a melasma amapindulitsa posankha chithandizo chamtsogolo.
Nthawi yotumiza: May-06-2022
