Patent ID: 8978653
Filing Date: 2015-03-17
Classification: A61M

Abstract:
1. A breathable gas mask arrangement for sealed delivery of a flow of pressurized breathable gas at a continuously positive pressure with respect to ambient air pressure to a patient's airways, wherein the breathable gas mask arrangement is configured to maintain a therapy pressure in a range of about 4cmH 2 O to about 25cmH 2 O above ambient pressure in use, throughout the patient's respiratory cycle, while the patient is sleeping, to ameliorate sleep disordered breathing, said breathable gas mask arrangement comprising: a mask shell having a portion adapted to receive a supply of said pressurized breathable gas and a patient side; a gusset portion having a first side attached to the patient side of the shell and having a second side; a cushion having a first portion attached to the second side of the gusset portion and a second portion constructed and arranged to contact a patient's face in use and provide a seal between the mask arrangement and the patient's face for delivery of said pressurized gas to the patient's airways; and wherein: a distance between the mask shell and the cushion is variable, and the gusset portion defines a projected area having an outer extent determinative of contact force applied to the patient's face, said projected area is variable to vary the contact force in use dependent on the distance between the mask shell and the cushion, and a maximum width of the gusset portion over an operating pressure range is greater that a width of the mask shell at the patient side of the mask shell.