Abstract: Cartridge apparatus (230) for use with a handle (220) is provided. The apparatus includes a housing (500) which: (a) includes a handle-coupling portion (235) shaped and sized to securely couple the housing to the handle and to facilitate separation of the housing from the handle, (b) shaped to define a skin-application portion (40) on an outer surface of the housing, and (c) includes at least one ultrasound element (60) in acoustic communication with the skin-application portion and configured to transmit ultrasound energy to the skin through the skin-application portion when the cartridge is attached to the handle. The cartridge apparatus also includes an inflatable element (250) inflated with a fluid, the fluid being in fluid communication with the skin-application portion. Other applications are also described.

Abstract: Apparatus (20) is provided comprising a skin-application portion (40), configured to move across skin of a subject. At least one acoustic element (50) is coupled to the skin-application portion (40) and configured to be placed in acoustic contact with the skin, and configured to apply ultrasound energy to the skin. The apparatus (20) additionally comprises circuitry configured to generate a current responsive to motion of the skin-application portion (40); and a control unit (10), which is configured to receive the current, to determine, responsive thereto, whether the skin-application portion (40) is moving with respect to the skin, and to drive the acoustic element (50) to apply the ultrasound energy to the skin responsive to determining that the skin-application portion (40) is moving with respect to the skin. Other embodiments are also described.

Abstract: A method is provided comprising placing an energy source coupled to a first support structure, at a first location on skin of an eyelid and placing a second structure at a second location on the skin of the eyelid, the second location being farther from the eye than is the first location. A portion of skin of the eyelid and underlying tissue is held between the first and second structures and treatment energy is transmitted from the energy source, from the first location away from the eye, through the tissue, toward the second location on the skin of the eyelid, while withholding transmission of treatment energy from the second location on the skin of the eyelid, toward the eye, through the portion of tissue, toward the first location on the skin of the eyelid. Other embodiments are also described.