METHOD AND APPARATUS FOR TREATING DERMAL MELASMA

摘要

Exemplary methods and devices can be provided for improving the appearance of dermal melasma. This can be done, e.g., focusing electromagnetic radiation having a wavelength between about 600 nm and 850 nm into a region of the pigmented dermal tissue at a depth between about 150 and 400 microns, using a lens arrangement having a large numerical aperture between about 0.5 and 0.9. The exemplary local dwell time of the focused radiation can be less than a few milliseconds, and a local fluence provided in the focal region can be between about 50 and 500 J/cm2. The focal region can be scanned through the dermal tissue at speeds on the order of a few cm/s. Such parameters can provide sufficient energy absorption by pigmented cells in the dermis to disrupt them while avoiding damage to the overlying tissue and unpigmented dermal tissue.

主权项

1. An apparatus for selectively affecting a plurality of pigmented regions in a dermis layer of a skin tissue, comprising:
a radiation arrangement configured to emit at least one electromagnetic radiation; and an optical arrangement configured to direct and focus the at least one electromagnetic radiation into a plurality of focal regions within the dermis layer when at least one portion of the apparatus contacts or is placed on a surface of the skin tissue, wherein the optical arrangement has a numerical aperture that is between about 0.5 and 0.9; wherein the radiation arrangement and the optical arrangement are configured to cause a fluence of the at least one electromagnetic radiation to be between about 10 and 1000 J/cm2 in the at least one focal region; and wherein the radiation arrangement and the optical arrangement are configured to at least one of thermally damage or disrupt the plurality of pigmented regions within the dermis while avoiding thermal damage to unpigmented regions and overlying tissue.