Cushion for patient interface

ES 2 556 590 T3

DESCRIPTION

Patient interface cushion

Cross references to requests

This application claims the benefit of US Provisional Applications No. 60 / 643,130, filed January 12, 2005, and 60 / 724,303, filed October 7, 2005.

Field of the invention

The present invention relates to a cushion for a patient interface, the patient interface being used in the treatment, for example, of Sleep Disordered Breathing Disorder (SDB) with Non-Invasive Positive Pressure Ventilation (NPPV, Non-Invasive Positive Pressure Ventilation).

Background of the invention

The use of NPPV for the treatment of SDB such as Obstructive Sleep Apnea (OSA) was first mentioned by Sullivan (see US Patent 4,944,310). An apparatus for treating SDB comprises a blower supplying a stream of air at positive pressure to a patient interface through a conduit. The patient interface can take various forms, such as a nasal mask unit and a nasal and mouth mask unit. Patients typically wear a mask unit while sleeping to receive NPPV therapy.

Mask units typically comprise a rigid cover or frame and a soft cushion for contact with the face. The frame and cushion define a cavity that receives the nose or nose and mouth. The frame and cushion are held in position on the patient's face by a helmet unit. The helmet unit typically comprises an arrangement of straps that run along the two sides of the patient's face to the back or crown of the patient's head.

US Patent 5,243,971 (Sullivan and Bruderer) describes a Continuous Positive Airway Pressure (CPAP) nasal mask unit that has an inflatable / moldable seal that conforms to the contours of the nose and face of the patient. patient. The mask unit has a face contacting portion mounted to a cover that is sized and shaped to fit the nose region of the patient. The face-contacting portion is in the form of a compliant membrane that is molded from an elastic plastic material. The compliant membrane and the cover together define a chamber. The pressurized gas that is admitted into the chamber causes the membrane to expand outward from the face of the patient.

US Patent 6,112,746 (Kwok et al.) Describes a nasal mask unit and a mask cushion therefor. The cushion comprises a substantially triangular shaped frame from which a membrane extends. The frame has an edge by which the cushion is attached to a mask body. The membrane has an opening into which the patient's nose is received. The membrane is spaced from the edge of the frame, and its outer surface is substantially the same shape as the edge.

EP1258266 describes a nasal treatment apparatus for CPAP with a flow generator that is coupled to a nasal mask. The mask has a nasal cushion that forms a receiving cavity for the nose. The cushion has a triangular shaped frame made of an elastic material with a mask engaging portion connected via a side wall to a face engaging portion having a nasal bridge region, a cheek region, and a lip region. . The cushion may have a side wall portion in the nasal bridge region shaped that is not straight to provide an improved seal in the nasal bridge region. A plurality of membranes, preferably three, of elastic material extend substantially around the triangular shaped frame. Some of the membranes are thicker in the lip region than in the nasal bridge region to improve the fit of the cushion in use.

WO20040222146 describes a respiratory mask unit for supplying breathing gas to a patient including a frame and a cushion. The cushion has a structured face non-contact portion to be connected to the frame, a structured face contact portion to engage the patient's face, and an intermediate portion that interconnects with the non-face contact portion. and the face contact portion. The intermediate portion includes a reinforcing portion that applies a first component of force to the patient's face through the face-contacting portion. A spring structure is coupled to the face contacting portion of the cushion. The spring structure applies a second component of force to the patient's face through the face-contacting portion. The first and second force components applied by the reinforcing portion and the spring structure, respectively, determine a contact force of the cushion applied to the patient's face through the face-contacting portion.

The cushion of a patient interface can play a key role in the comfort and effectiveness of therapy. There is considerable variation in facial size and shape which may mean that a mask designed for one type of

ES 2 556 590 T3 face may not be suitable for another. For example, an Asian nose tends to have a lower bridge of the nose while a Caucasian nose has a higher bridge of the nose. Using the wrong cushion can lead to excessive leakage and discomfort. Although creating custom cushions for each patient can solve some fit issues, custom masks are very expensive. Therefore, manufacturers seek to develop cushions that provide an effective and comfortable seal for a variety of facial shapes and sizes.

Compendium of the invention

One aspect of the invention is to provide a patient interface having a cushion that provides greater comfort to the patient while maintaining an effective seal, according to claim 1. Other features of the invention are defined in the dependent claims.

A patient interface is described that accommodates a wide variety of facial shapes and sizes.

A cushion is described. The cushion includes an underlying cushion and a membrane, where the underlying cushion and the membrane have a substantially flat portion in a nasal region of the cushion.

A cushion is described. The cushion includes a base wall, an underlying cushion, and a membrane, where the base wall and the underlying cushion have a cross-sectional configuration that provides a variable spring constant around the perimeter of the cushion.

A patient interface is described, where the base wall and the cushion frame connection are internally offset relative to the outermost point of the cushion, ie, the outer membrane surface.

A cushion is described. The cushion includes a base wall and an underlying cushion that are sloped or angled to one side of the nasal region of the cushion.

A cushion is described. The cushion has a substantially constant mouth width regardless of mouth height.

Another aspect of the invention relates to a cushion for a patient interface that supplies breathable gas to a patient. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane includes nasal bridge, cheek and chin regions adapted to form a continuous seal over the nasal bridge, cheek and chin regions of the patient's face, respectively. The nasal bridge region and the two adjacent cheek regions define an intersection or vertex. The membrane in the nasal bridge region has a height at the apex or intersection that is greater than a height in an adjacent portion of the cheek region.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane is adapted to form a continuous seal on the face of the patient. The underlying cushion has a spring-like connection to the base wall. The underlying cushion and / or base wall defines a spring constant that varies along a length of the seal.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane is adapted to form a continuous seal on the face of the patient. One of the membrane and the underlying cushion includes an outer surface defining an outer width of the cushion, and the base wall is internally offset relative to the outer surface.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall toward the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane includes at least nasal bridge and lateral nose regions adapted to form a continuous seal over the nasal bridge and lateral nose regions of the patient's face, respectively. The base wall and the underlying cushion in the lateral region of the nose are inclined or angled with respect to a lower part of the frame.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane includes nasal bridge, lateral nose, upper cheek, lower cheek, and chin regions adapted to form a continuous seal over the

ES 2 556 590 T3 regions of the nasal bridge, lateral of the nose, upper cheek, lower cheek, and chin of the patient's face, respectively. An inner edge of the membrane defines an opening that receives the face and mouth of the patient. A lower portion of the opening that receives the patient's mouth has a mouth width that remains substantially constant regardless of a cushion face height.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall toward the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane is adapted to form a continuous seal on the face of the patient. At least a portion of the underlying cushion and / or base wall has a lower portion that includes a spring configuration that defines displacement of the cushion with respect to an applied force from the frame.

A method for designing a series of mask units is described. The method includes providing a first cushion adapted to fit a greater variety of patients and providing a second cushion adapted to fit a lesser variety of patients. Each of the first and second cushions includes an opening that receives at least the patient's mouth. The opening of the first and second cushions has the same width.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane includes at least one nasal bridge region adapted to form a continuous seal over a nasal bridge region of the patient's face. The membrane forms an elongated protrusion in the nasal bridge region. The elongated boss has sloping sides that meet to form an elongated ridge. Each of the sloping sides is sloped from a center line of the ridge in the range of 30-60 ° and the ridge has a radius of curvature in the range of 1.0-5.0 mm.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane includes at least one nasal bridge region adapted to form a continuous seal over a nasal bridge region of the patient's face. The nasal bridge region of the membrane includes a contoured portion that curves inwardly toward a pocket of the cushion along a radius to terminate at an inner edge of the membrane. The contoured portion has a free end that is inclined relative to a plane of contact with the face of the cushion in the range of 30-50 °.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane is adapted to form a continuous seal on the face of the patient. The underlying cushion and / or base wall is shaped like a question mark or sickle.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane is adapted to form a continuous seal on the face of the patient. The underlying cushion has an arcuate configuration that includes an arc length greater than 16mm.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame, an underlying support cushion that extends away from the base wall towards the patient's face during use, and a membrane arranged to substantially cover at least one portion of the underlying cushion. The membrane is adapted to form a continuous seal on the face of the patient. The membrane includes a thickness that varies along the length of the seal.

A cushion for a patient interface that delivers breathable gas to a patient is described. The cushion includes a structured base wall for connection to a frame and a membrane adapted to form a continuous seal on the patient's face. At least a portion of the base wall includes a tapered portion that tapers toward the membrane.

A mask system is described that includes a set of at least two cushions arranged to fit different face sizes, where the at least two cushions are substantially the same width.

Other aspects, features, and advantages of this invention will be apparent from the following detailed description taken in conjunction with the accompanying figures, which are a part of this description and which illustrate, by way of example, principles of this invention.

ES 2 556 590 T3

Brief description of the invention

The attached figures facilitate the understanding of the different embodiments of this invention. In these drawings:

Figs. 1-9 illustrate a cushion for a patient interface constructed in accordance with one embodiment of the present invention and show exemplary dimensions of one embodiment;

Figs. 10-14 are cross-sectional views through the cushion shown in Fig. 5;

Fig. 15 is a front view of the cushion shown in Figs. 1-9 illustrating various regions of the cushion;

Figs. 16-17 illustrate another size of the cushion shown in Figs. 1-9;

Figs. 18-19 illustrate yet another size of the cushion shown in Figs. 1-9;

Figs. 20-21 illustrate yet another size of the cushion shown in Figs. 1-9;

Fig. 22 is a cross-sectional view through the cushion shown in Figs. 1-9 illustrating parameters that can modify a spring characteristic of the underlying cushion;

Figs. 23-29 are cross-sectional views through the cushion shown in Fig. 15 and showing exemplary parameters of an embodiment, where the cross-sectional views illustrate only the underlying cushion;

Figs. 30A-30N are cross-sectional views illustrating alternative embodiments of a cushion in accordance with the present invention;

Figs. 31-32 are graphs illustrating the general relationship between Force and Displacement for embodiments of the cushion shown in Figs. 1-9 and a known cushion sold commercially under the name UltraMirage® Full Face by ResMed Ltd .;

Fig. 33 is a graph illustrating the general relationship between Force and Displacement for various cross sections of the cushion shown in Figs. 23-29;

Fig. 34A illustrates a spring length for the cushion shown in Figs. 1-9, and shows exemplary dimensions of an embodiment in accordance with the present invention;

Fig. 34B illustrates a spring length for a known cushion sold commercially under the name UltraMirage® Full Face by ResMed Ltd., and showing exemplary dimensions of the UltraMirage® Full Face;

Fig. 35 is a side view of the cushion shown in Figs. 1-9;

Figs. 36-37 are cross-sectional views through the cushion shown in Fig. 35;

Fig. 38 is a front view of the cushion shown in Figs. 1-9 illustrating a flat portion thereof;

Fig. 38B is a graph illustrating the general relationship between Force and Displacement in a nasal bridge region for embodiments of the cushion shown in Figs. 1-9 and a known cushion sold commercially under the name UltraMirage® Full Face mask by ResMed Ltd .;

Figs. 39-40B are front and cross-sectional views of one embodiment of the cushion shown in Figs. 1-9, and show exemplary dimensions of an embodiment in accordance with the present invention;

Figs. 41-45 are perspective views of one embodiment of the cushion shown in Figs. 1-9 illustrating the displacing action of the nasal bridge region during use;

Figs. 46-53 illustrate a known cushion sold commercially under the name UltraMirage ® Full Face by ResMed Ltd .;

Figs. 54-58 illustrate a cushion for a patient interface in accordance with another embodiment of the present invention and show exemplary dimensions of one embodiment;

Figs. 59-63 are cross-sectional views through the cushion shown in Fig. 54;

Fig. 64 is a cross-sectional view of a portion of the cushion shown in Figs. 54-58 (solid line) superimposed on a cross section of a commercially known cushion sold under the name UltraMirage® Full Face by ResMed Ltd. (only the relevant parts of the UltraMirage® cushion are shown by the dashed lines, that is, there may be other different portions that are not shown);

Fig. 65 is a cross-sectional view of a portion of the cushion shown in Figs. 54-58 showing exemplary dimensions of an embodiment in accordance with the present invention;

ES 2 556 590 T3

Figs. 66-69 are cross-sectional views through the cushion shown in Fig. 54, and show exemplary dimensions of an embodiment in accordance with the present invention;

Figs. 70-71 are plan and cross-sectional views, respectively, of the cushion shown in Fig. 54, and show exemplary dimensions of an embodiment in accordance with the present invention;

<td>Figs. invention;</td><td> 72-76</td><td>they illustrate</td><td>a</td><td>cushion</td><td colspan="6">for a patient interface of</td><td colspan="7">according to another embodiment of the present</td>

<td>Figs.</td><td> 77-83</td><td>they illustrate</td><td>a</td><td>cushion</td><td>in order to</td><td>a</td><td>Interface</td><td>from</td><td>patient</td><td>from</td><td>agreement</td><td>with</td><td>other</td><td>realization</td><td>from</td><td>the</td><td>Present</td>

<td>invention;</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Figs.</td><td> 84-90</td><td>they illustrate</td><td>a</td><td>cushion</td><td>in order to</td><td>a</td><td>Interface</td><td>from</td><td>patient</td><td>from</td><td>agreement</td><td>with</td><td>other</td><td>realization</td><td>from</td><td>the</td><td>Present</td>

invention;

Fig. 91 illustrates an alternative cushion cross section relative to that shown in Fig. 34A;

Fig. 92 illustrates another alternative cross section relative to that shown in Fig. 34A;

Fig. 93 illustrates an alternative cushion arrangement to that shown in Fig. 15;

Figs. 94A-94C are a set of views showing a horizontal cross section through the nose bridge region of the cushion of Fig. 35; Y

Figs. 95A-95C are a set of views showing a horizontal cross section through the nose bridge region of the prior art cushion of Fig. 51.

Detailed description of the illustrated embodiments

Figs. 1-14 illustrate a cushion 10 constructed in accordance with one embodiment of the present invention. The cushion 10 is adapted to be detachably or permanently connected (eg, through mechanical and / or adhesive bonds) to a frame of a structured patient interface to deliver breathing gas to a patient. In one embodiment, the cushion may be co-molded to a frame of a patient interface. In another embodiment, the cushion may be part of a frame with an external support structure, for example, the ResMed Hospital Nasal Mask. The cushion 10 provides a seal to the patient's face during use.

In the illustrated embodiment, cushion 10 is part of a full face mask. Specifically, the cushion 10 provides a seal around the nose and mouth of the patient to allow delivery of breathable gas to the nose and mouth of the patient. However, aspects of the present invention may be applicable to other breathing arrangements, for example, a nasal mask, a mouth mask, etc. The cushion 10 can be used with a reinforcement as described in US Patent Application 10 / 655,622.

The cushion 10 is structured to provide a more comfortable fit for a wide range of facial shapes and sizes. Also, the cushion 10 is structured to provide a better seal and reduce the risk of leakage as described below.

As illustrated in Figs. 1-14, the cushion 10 includes a structured face non-contact portion 12 for connection to a frame of the patient interface, eg, through a friction connection, a tongue and groove arrangement, etc. , and a face contacting portion 14 structured to engage the face of the patient.

As shown in greater detail in Figs. 5 and 15, the face-contacting portion 14 of the cushion 10 preferably has a generally triangular shape and is structured to continuously contact the nasal, lateral nose, upper cheek, lower cheek, and chin regions of the patient. However, the face-contacting portion 14 may have other suitable shapes, for example, a generally trapezoidal shape. In the illustrated embodiment, as shown in greater detail in Fig. 15, the cushion 10 illustrates a nasal bridge region 16 to provide a seal along the patient's nasal bridge, a pair of cheek regions 15 to provide a sealing along the nose, cheeks and mouth of the patient, and a chin region 20 to provide a seal along the chin of the patient. The pair of cheek regions 15 may further be defined as a pair of lateral nose regions 17 to provide a seal along the sides of the patient's nose, a pair of upper cheek regions 18 to provide a seal to along the patient's upper cheeks, and a pair of lower cheek regions 19 to provide a seal along the patient's lower cheeks and the sides of the patient's mouth.

Cushion width in lower cheek regions and face width to height ratio of mask sizes

The cushion 10 can be provided in various sizes to accommodate various facial sizes. For example, Figs. 16-21 illustrate embodiments of cushion 10 in three other sizes. In one embodiment, the cushion 210 shown in Figs.

ES 2 556 590 T3

16-17 may represent an extra small size, the cushion 310 shown in Figs. 18-19 may represent a small size, the cushion 10 shown in Figs. 1-14 may represent a medium size, and the cushion 410 shown in Figs. 20-21 may represent a large size. As illustrated, the width of the mouth of the cushions 10; 210; 310; 410 is substantially constant regardless of your face height.

Specifically, cushion 10 defines an opening 22 that receives the patient's mouth. In a preferred embodiment, the lower portion of the opening 22 has a constant width for all cushion sizes, for example 60mm. However, the width of the lower portion of the opening 22 can be nearly constant, for example in a range of 5mm, for all cushion sizes. For example, the width of the lower portion of the opening 22 of the cushion 10 may be 60 ± 5 mm. In contrast thereto, the width of the lower portion of the opening 722 of a commercially known cushion 700 sold under the name UltraMirage® Full Face by ResMed Ltd. is 60 mm for a large size, 54 mm for a medium size, and 52 mm for a small size. The 700 UltraMirage® cushion is shown in Figs. 46-53.

Anthropometric data indicate that the mouth width of patients with relatively small faces is not necessarily narrower than the mouth width of patients with relatively large faces. Therefore, all faces generally have the same mouth width. Thus, the opening 22 of the cushion 10 is made wide enough to accommodate a wide variety of patients and remains constant or nearly constant, for example, a range of 5mm, regardless of the change in face height of a mask to fit. to bigger faces. This can be seen in the substantially constant cushion geometry around the lower cheek and chin regions of the different cushion sizes, and thus the varying width-to-height ratio of the different cushion sizes. For example, the lower portion of the opening 22 of each of the cushions 10, 210, 310, 410 has substantially the same width.

Base wall, underlying cushions and membrane

As shown in greater detail in Figs. 9 and 10-14, the face-contacting portion 14 of the cushion 10 includes a base wall 28, a pair of underlying support cushions 30 extending away from the base wall 28, and a membrane 32 arranged to cover substantially at least a portion of the underlying cushions 30 and provide a sealing structure for the face-contacting portion 14. Base wall 28 and underlying cushions 30 provide a supporting structure for membrane 32.

As illustrated, the underlying cushions 30 are preferably disposed only on lateral sides of the base wall 28, for example in the lateral regions 17, 18, 19 of the nose, upper cheek, and lower cheek, although the underlying cushions 30 could be attached and substantially surround the nose of the patient and also the region of the lower lip or chin. The underlying cushions 30 add rigidity to the membrane 32 on the sides of the patient's mouth and cheeks. Although it is preferable that the membrane 32 is thinner than the underlying cushions 30, they may be the same thickness or the membrane may be thicker than the underlying cushion. Also, the elimination of an underlying cushion in the chin region 20 allows the cushion 10 to better engage the patient's face in this region without subjecting the patient's chin region 20 to excessive pressure. That is, there is no underlying cushion to restrict the movement of membrane 32 in this region, which can improve sealing in this region and adjacent regions.

Additionally, the elimination of an underlying cushion in the chin region 20 allows the cushion 10 to accommodate more facial shapes and provides more flexibility and allows movement or opening of the mouth.

In the illustrated embodiment, the cushion face-contacting portion 14 has a double-walled construction, i.e., membrane 32 and underlying cushion 32, in the nose, upper cheek, and lower cheek regions 17, 18, 19, and a single wall construction, ie membrane 32, in the nasal bridge and chin regions 16, 20, as shown in Figs. 10-14. The single wall construction at the top and bottom of cushion 10 helps to accommodate high points, eg, pointed chin, allowing the center of cushion 10 to flex. This flexibility allows more patients to be accommodated with the same cushion. However, the cushion 10 may have any other suitable construction, for example, single-walled, double-walled, single-walled, or with more walls, in any suitable region of the cushion 10, for example the cheek, chin, or bridge. nasal. For example, the underlying cushion 30 may extend around the entire perimeter of the cushion 10. Also, the underlying cushion 30 could be completely removed.

As shown in Figs. 10-14, the thickness of the membrane can vary in the different regions of the cushion 10. As illustrated, the membrane in the nasal bridge region 16 and the upper cheek region 18 has a thickness of 0.3 mm which follows a transition to a thickness of 0.5 mm in the upper cheek region 18 and maintains this thickness in the lower cheek and chin regions 19, 20. This arrangement provides greater compliance / stretch in the nasal bridge by having a thinner membrane. This stretching is not necessary in the lower regions and here the thinner membrane is less prone to vibrate on the patient's face during use.

Base wall and frame connection internally offset

Another aspect of the invention relates to the size and configuration of the base wall 28, underlying cushion 30, and

ES 2 556 590 T3 membrane 32 of cushion 10. Figs. 48-50 illustrate the base wall 728, the underlying cushion 730, and the membrane 732 of the UltraMirage® cushion 700.

For example, as shown in greater detail in Figs. 11-13, the base wall 28 and the frame connection 29 are internally offset from the outermost point 39 of the cushion, eg, the outer surface of the membrane or the underlying cushion. In contrast, the base wall 728 and connection 729 of the UltraMirage® cushion 700 are not offset relative to the outermost point 739 of the cushion (see Figs. 48-50). As a result of this inward movement, the width of the cushion base 10 narrows, for example a distance of 5mm or 2.5mm per base, which provides a less obtrusive cushion and saves material, which means less weight. and cost. Also, the narrower cushion 10 implies a shorter free length of the cushion 10 that protrudes outwardly during use, thus helping to minimize or eliminate leakage.

As illustrated, a lower portion of the underlying cushion 30 has a more arcuate, eg, semicircular, question mark, sickle-shaped configuration defining a space 34 under a lower portion of the cushion 30 underlying and adjacent to the base wall 28.

In the illustrated embodiment, the outermost or widest point of the cushion is the outer surface of the underlying cushion 30 and the base wall 28 and frame joint 29 are internally offset from it. Therefore, by the design of the cushion 10 and in particular the curvature of the underlying cushion, the frame is fixed at a narrower point and thus the frame itself is narrower. This arrangement has significant advantages in terms of frame weight, perceived volume, and size. This arrangement also minimizes dead space within the mask, helping to reduce re-breathed CO2.

In addition, the space 34 under the underlying cushion 30 allows a greater range of movement of the underlying cushion 30 to add more flexibility to the underlying cushion 30 and thus to the membrane 32 in use. Specifically, the space 34 under the underlying cushion 30 allows for greater displacement of the underlying cushion 30 using substantially the same space restrictions as the UltraMirage® cushion 700, for example. Additionally, the space 34 allows for greater displacement of the underlying cushion 30 before flattening, thereby reducing discomfort. Therefore, this arrangement provides a more gradual force, improves comfort, and allows a wider range of patients to achieve a seal.

Variable spring constant

As illustrated, the underlying cushion 30 has a spring-like connection to the base wall 28 such that the underlying cushion 30 can be displaced relative to the base wall 28. That is, the underlying cushion 30 can move in space 34 (the underlying cushion 30 can also move in space 33). Thus, a spring force is provided when a frame force is applied and the underlying cushion 30 is elastically moved back to its initial position when the frame force is released. The underlying cushion 30 and / or the base wall 28 can have any suitable spring constant, and the spring constant can vary anywhere along its length, for example by tapering and varying the thickness of the wall 28. base, a variation in the thickness of the intermediate and / or lower portions of the underlying cushion 30. Also, the spring-like connection can extend the entire length of the underlying cushion 30 or the spring-like connection can be located in certain regions such as the cheekbone region.

Thus, a spring feature is molded with the base wall 28 and the underlying cushion 30 of the cushion 10 which allows a continuously variable spring constant to be incorporated into the base wall 28 and the underlying cushion 30, for example, the wall stiffness in each cushion region to accommodate sealing requirements in each region, which may vary due to the underlying facial structure of the patient.

The spring characteristics of the base wall 28 and the underlying cushion 30 can be modified by varying several of the characteristics shown in Fig. 22. For example, the spring characteristics can be modified by varying the height h of the underlying cushion, the thickness t, the radius r, and the displacement c of the underlying cushion. It should be understood that these parameters are exemplary only, and that other parameters may be varied to modify the spring characteristics of the base wall 28 and the underlying cushion 30.

Figs. 23-29 illustrate parameters of one embodiment of the underlying cushion 30 and base wall 28 to achieve the desired spring characteristics. As illustrated, underlying cushion 30 and base wall 28 are configured to provide a variable spring constant along the perimeter of cushion 10. That is, the spring constant of the underlying cushion 30 and the base wall 28 differ along the lateral regions 17, 18, 19 of the nose, upper cheek, and lower cheek. Although in Figs. 23-29 specific parameters of cushion 10 are shown, it should be understood that these parameters are only exemplary and that other parameters are possible depending on the application.

In the nasal bridge region 16 (eg, see FIG. 10), no underlying cushion 30 is provided to provide high flexibility and the ability to conform to a variety of facial shapes. However, in one embodiment, there may be an underlying cushion 30 with a very soft spring characteristic in this region.

In regions 17 on the lateral side of the nose (see Figs. 23-24), an underlying cushion 30 and a wall are provided

ES 2 556 590 T3 base with a fairly rigid spring feature to provide lateral stability to squeeze the side of the patient's nose and keep the membrane 32 in contact with the underlying cushion 30. As illustrated, this arrangement is achieved by a relatively thick underlying cushion, a small height, and a narrow radius. In one embodiment of the section shown in Fig. 23, h can be 12mm, r can be 5mm, t can be 2-3mm, b can be 4mm, w1 can be 11.5mm, and w2 can be 8mm. In one embodiment of the section shown in Fig. 24, h can be 14mm, r can be 6-7mm, t can be 2.5mm, b can be 4mm, w1 can be 11.5mm, w2 it can be 9.5 mm, and α can be 22 °. It should be understood that these dimensions and ranges are exemplary only and that other dimensions and ranges are possible depending on the application.

Also, as shown in greater detail in Fig. 24, the base wall 28 and the underlying cushion 30 in the regions of the side of the nose have been rotated about 22 degrees with respect to the bottom of the frame. That is, the base wall 28 and the underlying cushion 30 are sloped or angled in the lateral regions 17 of the nose of the cushion 10. This arrangement further increases lateral stability and allows the force on the membrane to be applied perpendicular to the surface of the skin on the side of the patient's nose. This further helps to keep the membrane 32 in contact with the patient's skin and to prevent air leakage. In other embodiments, this angle can range from 15 to 30 degrees.

In the upper cheek regions 18 (see Figs. 25-26), the underlying cushion 10 and the base wall 28 have a stiffness that is less than that provided in the lateral regions 17 of the nose but stiffer than that provided. in the lower cheek regions 19 due to the geometry of the underlying cushion, this is thus arranged to conform to the firmer bone structure of the upper cheeks. In one embodiment of the section shown in Figs. 25, h can be 12-15mm, preferably 13.5mm, r can be 5mm, t can be 2mm, b can be 3mm, and w1 can be 11.5mm. In one embodiment of the section shown in Fig. 26, h can be 12-15mm, preferably 13.5mm, r can be 5mm, t can be 2mm, b can be 3mm, and w1 can be 11 , 5 mm. It should be understood that these dimensions and ranges are exemplary only and that other dimensions and ranges are possible depending on the application.

In the lower cheek regions 19 (see Figs. 27-29), the underlying cushion 30 and the base wall 28 have a relatively low spring constant. That is, the underlying cushion 30 in the lower cheek regions 19 is quite soft because the fleshy region of the patient's cheek is easily deformed to form a seal with the cushion with relatively low forces. As illustrated, this arrangement is achieved by a greater height h, greater radii r, and a thinner underlying cushion wall. In one embodiment of the section shown in Fig. 27, h can be 14mm, r1 can be 5mm, r2 can be 7mm, t can be 1.5-2mm, b can be 3.5mm, and w1 can be 11.5mm. In one embodiment of the section shown in Fig. 28, h can be 16.5mm, r1 can be 6-7mm, r2 can be 8mm, t can be 1.5mm, b can be 3.5mm , and w1 can be 11.5 mm. In one embodiment of the section shown in Fig. 29, h can be 17.5mm, r1 can be 6-7mm, r2 can be 9-10mm, t can be 1.5mm, b can be 3, 5mm, and w1 can be 11.5mm. It should be understood that these dimensions and ranges are exemplary only and that other dimensions and ranges are possible depending on the application.

In the chin region 20 (see Fig. 14), no underlying cushion 30 is provided, although a very flexible spring region can be used. The chin region 20 provides an unrestricted membrane region that allows lateral movement, movement or opening of the mouth, and a variety of facial shapes.

Thus, the cushion 10 can be configured to provide different vertical and / or lateral stiffness in different regions of the cushion. For example, the lateral regions 16, 17 of the nose are stiffer than other regions to provide more lateral stability to the patient's nose.

Alternative realizations of the base wall and the underlying cushion

Figs. 30A-30N illustrate alternative embodiments of base wall 28 and underlying cushion 30. Each of these embodiments provides an arrangement that allows flexibility of the underlying cushion 30 in use. In FIG. 30A, the underlying cushion 30 defines an enclosed space 60 that can optionally be filled with pressurized air, foam, gel, or an elastomeric material and adapted to damp the movement of the underlying cushion 30 in use. In Fig. 30B, the space 34 under the underlying cushion 30 is within the interior of the breathing cavity. Also, the underlying cushion 30 has an arcuate shape that curves away from the interior of the breather cavity towards the base wall 28. However, the underlying cushion 30 can have any other suitable shape. For example, the underlying cushion 30 of Fig. 30C has a bulb shape, which can be solid or hollow. In Fig. 30D, the underlying cushion 30 has a general Z-shape. In Figs. 30E and 30F, the underlying cushion 30 has a bulb shape (which can be solid or hollow), and the space 34 under the underlying cushion 30 has a ramp configuration. In Figs. 30C, 30E and 30F, the bulb form can optionally be filled with pressurized air, foam, gel, or an elastomeric material and adapted to damp the movement of the underlying cushion 30 in use. In fig. 30E, the ramp configuration of space 34 is adapted to direct the underlying cushion 30 down into the base wall 28 in use, and in Fig. 30F the ramp configuration of space 34 is adapted to direct cushion 30 inward toward the breathing cavity in use. In Figs. 30G, 30H and 30I, the underlying cushion 30 has a general T-shape. Also, in Figs. 30H and 30I, the base wall 28 defines a closed space 62 under the underlying T-shaped cushion 30. The closed space 62 may optionally be filled with pressurized air, foam, gel, or an elastomeric material and be adapted

ES 2 556 590 T3 to damp the movement of the underlying cushion 30 in use. Furthermore, the spring constant can be varied by modifying the pressure within the closed space 62. Additionally, the bottom surface of the space 62 may have a ramp configuration (as shown in FIG. 30H) adapted to direct the underlying cushion 30 inwardly towards the breathing cavity in use. The bottom surface of the enclosed space 60 in Fig. 30A may also have a ramp configuration to direct the underlying cushion 30 in use. In Figs. 30J and 30K, the underlying cushion 30 has an elongated section for soft spring characteristics. Fig. 30L illustrates a single wall construction with an underlying cushion 30 and no membrane. In Fig. 30M, the space 34 under the underlying cushion 30 is greatly increased. In Fig. 30N, a spring construction is provided under the base wall 28.

Displacement provided by the underlying cushion

The space 34 allows for greater displacement of the underlying cushion 30 for a predetermined amount of force when compared to the UltraMirage® cushion 700. That is, the underlying cushion 30 allows greater movement for a given force. For example, Fig. 31 illustrates the general relationship between Force and Displacement for cushion 10 and UltraMirage® cushion 700. As illustrated, the curve of the cushion 10 is flatter than the exponential curve of the UltraMirage® cushion 700. Therefore, the underlying cushion 30 is less rigid and more compliant compared to the UltraMirage® cushion 700. It is necessary to mention that the space 34 could be filled with a gel, silicone or any other structure to modify the spring characteristic that it provides.

Furthermore, as illustrated in FIG. 31, the point B10 where the cushion 10 is fully compressed or flattened is further offset than the point B700 where the UltraMirage® cushion 700 flattens. Furthermore, the flattening point B10 is produced with a greater force than the flattening point B700. Thus, the cushion 10 increases the force required for flattening, and provides a wider range of adjustment. Additionally, Fig. 31 illustrates an example of maximum and minimum comfortable sealing forces, providing an example of the range of forces required to achieve sealing. As illustrated, the A10 range of displacement within this force range for the cushion 10 is substantially greater than the A700 range of displacement within this force range for the 700 UltraMirage® cushion. Thus, the cushion 10 allows a wide range of adjustment or movement to achieve sealing, and ensures that the sealing force is substantially less than the flattening force so that the cushion does not have to be flattened to achieve sealing.

FIG. 32 illustrates another embodiment of the Force-Displacement relationship for the cushion 10 and the UltraMirage® cushion 700. In this embodiment, the linear portion of the curve for cushion 10 has a greater slope than the linear portion of the curve for cushion 10 of FIG. 31. The difference in slope can be attributed to a difference in spring constants of the respective underlying cushions 30. Therefore, the cushion represented in Fig. 31 provides more displacement for a given force than the cushion depicted in Fig. 32. Also, the curve for cushion 10 in Fig. 32 intersects the curve for UltraMirage® cushion 700, so that the force of cushion 10 is greater with a smaller displacement, to ensure a seal, and a smaller one with a greater displacement, to maintain comfort for a greater range of displacements.

Fig. 33 illustrates another embodiment of the Force-Displacement relationship for the cushion 10. In this embodiment, typical curves are shown for the different regions of the cushion 10. Specifically, one curve represents the cross sections of Figs. 23-24 on the side of the nose region 17, another curve represents the cross sections of Figs. 25-27 in upper cheek and lower cheek regions 18, 19, and yet another curve represents the cross sections of Figs. 28-29 in region 19 of lower cheek. As illustrated, the cushion 10 is softer or less rigid in the lower regions of the cushion 10.

Extended spring length on underlying cushion

Figs. 34A and 34B illustrate the extended length of the flexible underlying cushion 30 which is used to provide a softer spring characteristic in selected regions of the cushion 10 compared to a typical prior art cushion, for example the UltraMirage® cushion 700. The length a through b can be deformed, thus providing a spring characteristic. As illustrated, the length from a to bd cushion 10 (Fig. 34A) is considerably longer compared to the UltraMirage® cushion 700 (Fig. 34B) due to the curvature of the underlying cushion 30. In the illustrated embodiment, the length a through b of the cushion 10 is 22.84. However, in one embodiment, the length a through b of the cushion 10 may be within the range of 16-30, preferably 20-25, and more preferably 22-24. In another embodiment, the length a through b of the cushion 10 may be in the range 16-20. The length from b to c is quite stiff and does not deform to provide a spring characteristic. The added length in the cushion 10 has been achieved by the arcuate shape of the underlying cushion 30 and the gap 34 is a result of this shape. This added length adds flexibility and a greater range of motion to the cushion 10. Figs. 30J and 30K illustrate other embodiments to achieve greater section length.

Membrane configuration in the nasal bridge region

The membrane 32 is structured to form an effective seal around the nasal bridge, lateral nose, upper cheek, lower cheek, and chin regions 16, 17, 18, 19, 20 of a patient. Another aspect of the invention relates to the configuration of the membrane 32 in the region 16 of the nasal bridge of the cushion 10, which has been

ES 2 556 590 T3 structured to improve sealing and comfort in this region.

Specifically, as shown in a preferred embodiment in Fig. 36 and in an alternative embodiment in Fig. 68, the membrane 32 forms an elongated shoulder 35 in the region 16 of the nasal bridge where the sloping sides 36 meet to form a crest 38 elongated. Each of the sloping sides 36 is sloped from the center line of the ridge within the range of 30-60 °, preferably about 47 °. The crest 38 has a radius of curvature within the range of 1.0-5.0mm, preferably about 2.5mm. As illustrated, the underlying cushion 30 has been removed from the underside of the membrane 32 in the region 16 of the nasal bridge, allowing the membrane 32 to move freely in this region between the underlying cushions 30 arranged in the regions 17 sides of the nose. As described in greater detail below, this membrane configuration allows for the creation of an inverted sloping section when engaging with the patient's nose, improving fit, comfort, and sealing in region 16 of the bridge. nasal. In contrast, the 700 UltraMirage® cushion is relatively flat in this region (see Fig. 52).

As shown in a preferred embodiment in Fig. 37 and in an alternative embodiment in Fig. 69, the forward end of the elongated boss 35 has an elongated configuration. The forward end 40 is structured to engage the region of the patient's nasal bridge and has a radius of curvature within the range of 1.5-7.00mm, preferably about 4.0mm.

Sharp profile of the cross section of the nasal bridge region

As shown in Fig. 10, the membrane 32 in the nasal bridge region 16 has a sharper cross-sectional profile than the corresponding portion of the UltraMirage® cushion 700 (see Fig. 48). Specifically, membrane 32 provides a large contoured portion that curves inwardly toward the cushion cavity along a radius to terminate at an inner edge of membrane 32. This arrangement more closely follows the contour or curvature of the patient's nasal bridge region. In the illustrated embodiment, the membrane 32 is inclined relative to a face that contacts the plane of the cushion, for example in the range of 30-50 °. In contrast, the corresponding angle of the 700 UltraMirage® cushion is around 6 °. This embodiment provides more comfort and a better fit for the patient.

Flat portion in the region of the nasal bridge

As best shown in FIG. 38, the nasal bridge region 16 has a substantially flat portion 50, for example, at the apex of the membrane curvature, in an elevation view that can be deformed to provide a more comfortable fit for a wide variety of patients, for example from flatter nose bridges to sharper nose bridges.

Specifically, one aspect of the invention is to provide a membrane 32 in the nasal bridge region 16 that accommodates "flat faces", for example, those patients who have a low nasal bridge. To achieve this, the cushion 10 has an upper point A that is higher than, or level with, the points B (see Fig. 38). This height in the nasal bridge region 16 is combined with a rounded edge that keeps the surface area of ​​the membrane 36 substantially flat against the patient's nasal bridge. Keeping the surface area of ​​the membrane 36 substantially flat against the patient's nasal bridge prevents leakage at the edge of the membrane.

The rounded edge also allows movement to accommodate higher nasal bridges. This embodiment is achieved without "stretching" the membrane, which can cause discomfort and pain to the patient. For example, the displacement of the cushion 10 in the region 16 of the nasal bridge may be greater than about 40 mm, for example mm. In contrast, the 700 UltraMirage® cushion provides a displacement of around 20mm in the nasal bridge region. With these displacements, the membrane becomes quite tight, that is, the point on the force versus displacement graph at which the force begins to rise abruptly for a small displacement (see Fig. 38B).

The cushion displacement values ​​in the nasal bridge region for some cushions according to the prior art are as follows:

ResMed ™ Activa® Nasal Cushion - 16mm

Respironics Comfort Full Face Cushion - 26mm

ResMed Bubble Nasal Mask Cushion - 43mm

Healthdyne soft series nasal mask cushion - 17 mm

The above displacement values ​​are in no way an accurate representation of the nose depth covered by the cushion. Instead, these displacement values ​​are only an indication of the flexibility and / or range of the membrane. Thus, cushion 10 provides an arrangement that is much more flexible and / or streamlined than UltraMirage® cushion 700, for example.

ES 2 556 590 T3

The force versus displacement graph of membrane 32 in the nasal bridge region 16 has a large displacement for relatively low forces. For example, as shown in Fig. 38B, the displacement provided by cushion 10 in the nasal bridge region 16 is greater than that provided by UltraMirage® cushion 700. This allows cushion 10 to accommodate relatively deep nasal bridges during use. In addition, the molded (undeformed) state of the 700 UltraMirage® cushion (ie, without being subjected to any force) does not comfortably accommodate a relatively flat or low bridge of the nose. In one embodiment, the cushion membrane 700 bursts to conform to patient faces with low nasal bridges. Therefore, the cushion 10 also accommodates a wider range of nose bridge shapes than the 700 UltraMirage® cushion.

Additionally, as shown in Fig. 36, the membrane profile has a sharper peak compared to a flat profile or saddle profile (for example, compared to the 700 UltraMirage® cushion in Fig. 52). Also, as shown in Fig. 35, the flat portion of the nasal bridge region 16 extends along a relatively flat plane P1, and this plane P1 is inclined at an angle A relative to the plane P2 that defines the frame connection.

Thus, the shape (eg, beak), rounded edge, and height, in region 16 of the nasal bridge provide high displacement with relatively low forces. This arrangement accommodates a wider variety of patients, for example, from those with a low nasal bridge to those with a high nasal bridge, while maintaining a seal against the patient's face with little force on the membrane.

It should be noted that the height of the cushion can vary around the perimeter of the cushion to vary the flexibility or displacement of the cushion in different regions of the cushion. A reference dimension 940 is shown in Fig. 94C for the cushion height measurement (which can also be referred to as the membrane height), that is, the height between the vertex of the membrane and the place where it meets the underlying cushion. In Fig. 95C reference dimension 950 is shown for cushion height measurement in prior art cushion.

Diaphragm opening

As shown in Figs. 39-40B, the inner edge of the membrane 32 defines the opening 22 that receives the nose and mouth of the patient. As illustrated, aperture 22 is generally triangular in shape. Furthermore, the apex of the opening 22 has a rounded notch 42, that is, a hole. Notch 42 improves sealing with nasal bridge regions of various sizes and shapes, particularly in patients with sharp noses. The notch 42 has a radius of curvature within the range of 1.5-6.0mm, preferably about 3.0mm. This rounded hole shape has a length, for example the hole shape extends outward from an inner portion of the cushion, of about 3.0mm, as shown in Fig. 40A.

Displacing action of the nasal bridge region of the cushion during use

Figs. 41-45 include hand-scored lines applied to the outer surface of the nasal bridge region 16 of the cushion 10 to illustrate the displacing action of the nasal bridge region 16 of the membrane 32 when coupled to the patient's nose. As described above, the membrane 32 in the nasal bridge region 16 includes sloping sides 36 that meet to form an elongated ridge 38 as shown in FIG. 41. When the patient's nasal bridge (which is simulated using a small rod) is coupled to the nasal bridge region 16 of the membrane 32 (see Fig. 42), the membrane 32 creates a strongly inverted section 44 where the sloping sides 36 they reverse their position as the membrane 32 moves between the underlying cushions 30 arranged in the lateral regions 17 of the nose. As the membrane 32 comes in more contact with the patient's nasal bridge, the leading edge 46 of the inverted section "drifts" toward the top of the cushion 10 as the membrane 32 conforms to the patient's face according to shown in Fig. 43. This structure is advantageous in that it allows the cushion 10 to accommodate patients who have a wide range of nasal profiles, including those with a relatively low and relatively high base depth of the nose. Figs. 44 and 45 show the nasal bridge region 16 of membrane 32 in its fully inverted position. The creation of the strongly inverted section 44 when engaged with the patient's nose provides a better seal and reduces the risk of kinks and / or creases and the associated discomfort and leakage. That is, this configuration encourages displacement rather than folding which can be detrimental to patient comfort and sealing.

Alternative realizations

Figs. 54-71 illustrate another embodiment of a cushion 510. In each of the figures, portions of cushion 510 that are substantially similar to cushion 10 are indicated.

Fig. 64 illustrates the base wall 528, the cushion 530, and the membrane 532 of the cushion 510 (in solid lines) relative to the base wall 738, the underlying cushion 730, and the membrane 732 of the UltraMirage® cushion 700. Full Face (dashed line). As illustrated, the 510 cushion has a different cross-sectional profile than the 700 UltraMirage® Full Face cushion.

For example, the membrane 532 is connected to the underlying cushion 530 in a position that is arranged more

ES 2 556 590 T3 inward and upward relative to the 700 UltraMirage® cushion membrane connection. This arrangement substantially eliminates the vertically extending slot 731 provided in the UltraMirage® cushion 700. Furthermore, this arrangement narrows the width of the membrane 532, for example in the range of 0-5, preferably about 2.5 mm, relative to the corresponding portion of the UltraMirage® cushion 700. As a result of this and the inward movement of the non-face-contacting portion 512, this narrows the overall width of the cushion 510 to about 5mm, for example about 2.5mm per base, providing less cushion. obtrusive and saves material. In addition, the narrower membrane 532 provides a shorter free length for the cushion 510 to protrude outward during use, thus helping to minimize or eliminate leakage. In addition, base wall 528 and frame connection 529 are internally offset relative to the outermost point of the cushion, eg, the outer surface of the underlying cushion. Fig. 64 also shows the greater length a through b in cushion 510 compared to UltraMirage® cushion 700.

FIG. 65 illustrates further structural details and dimensions in one embodiment of the base wall 528, the underlying cushion 530, and the membrane 532 of the cushion 510. For example, the depth of space 534 is within the range of 0-4, 0mm, preferably about 3.0mm.

FIG. 68 illustrates elongated boss 535 in nasal bridge region 516. Each of the sloping sides 536 is sloped from the center line of the ridge in the range of 30-60 °, preferably about 47 °. The crest 538 has a radius of curvature in the range 1.0-5.0mm, preferably about 2.5mm. As shown in Fig. 69, the forward end 540 of the elongated boss 535 has a radius of curvature in the range of 1.5-7.0mm, preferably about 4.0mm.

Figs. 70 and 71 illustrate the flat portion 550 in the nasal bridge region 516 of the cushion 510. Also, as shown in Fig. 71, the membrane 532 of the nasal bridge region 516 has a first portion with a radius of curvature at the range of 50-80mm, preferably about 65mmm, and a second portion with a radius of curvature in the range of 5.5-9.5mm, preferably about 7.5mm. In the illustrated embodiment, the membrane 532 is inclined with respect to a plane of the cushion that contacts the face in the range of 30-50 °, preferably 40 °.

Figs. 72-76 illustrate another embodiment of a cushion 610. As shown in greater detail in Fig. 76, the cushion includes at least a base wall 628 and a membrane 632. As illustrated, the length of the membrane 632 (by For example, the cross-sectional length of the membrane) in a nasal bridge region can change. For example, the length of the membrane can be selected to have a shorter L1 length or a longer L2 length in the region of the nasal bridge.

As shown in Figs. 74 and 75, the length of the membrane controls how far along the patient's nose the displaced cushion membrane will rest when fitted over the patient's face (shown by a dotted line on the patient's facial profile ). This arrangement prevents potentially (for example, particularly for patients with a shallow nasal bridge depth) an excess cushion membrane from resting too far along the patient's nose, which can lead to facial discomfort and markings on the nose. skin of the patient's nose.

Figs. 77-83 illustrate another embodiment of a cushion 810. The cushion 810 includes a base wall 828, an underlying support cushion 830, and a membrane 832. As described above, the underlying cushion 830 is preferably disposed only on lateral sides. of the cushion 810.

The base wall 828 may be internally offset from the outermost point of the cushion, for example the outer surface of the underlying membrane or cushion. This arrangement provides a spring characteristic that can vary along the perimeter of the cushion to vary the flexibility of the cushion (lateral and / or vertical) around the perimeter of the cushion, for example, the stiffness of the cushion can vary in each region of the cushion. to accommodate the sealing requirements in each region which may vary due to the underlying facial structure of the patient. That is, the level of deflection (eg, from "hard" to "soft") along the sides of the cushion can be changed.

For example, Figs. 77-83 illustrate cross sections through three different regions R1, R2, R3 of cushion 810. As shown in Fig. 81, base wall 828, underlying cushion 830, and membrane 832 cooperate to define a surface. 880 external relatively straight. This provides a minimal spring component in the R1 region, for example stiffness or stiffness characteristics.

As shown in Fig. 82, base wall 828, underlying cushion 830, and membrane 832 cooperate to define an outer surface 882 that transitions from a relatively straight configuration to a curved configuration. This provides a relatively small deflection for a spring component more flexible than the R1 region.

As shown in Fig. 83, base wall 828, underlying cushion 830, and membrane 832 cooperate to define an outer surface 884 that curves outward from base wall 828. This provides a relatively large deflection for an optimal spring component in the R3 region, eg, soft or flexible characteristics.

ES 2 556 590 T3

Thus, cushion 810 can be designed to provide variable flexibilities along its perimeter that allow cushion 810 to conform to a variety of facial shapes.

Figs. 84-90 illustrate another embodiment of a cushion 910. The cushion 910 includes a base wall 928, an underlying support cushion 930, and a membrane 932. As illustrated, the underlying cushion 930 is preferably disposed only on lateral sides of the cushion. 910, for example, there is no underlying cushion in the nasal bridge and chin regions (see Fig. 88).

As shown in Fig. 90, base wall 928 includes a tapered portion 990 compared to Fig. 89, which tapers toward membrane 932. This arrangement can improve moldability.

Fig. 91 illustrates an alternative embodiment to the cushion 10 of Fig. 34A (arrangement of Fig. 34A shown in broken line). As illustrated, material has been removed from side wall 28 and gap 34 has been reduced relative to the arrangement of Fig. 34A. This arrangement of Fig. 91 increases the offset relative to the previous offset of Fig. 34A. The increased displacement is achieved by changing the geometry of the side wall 28. It is necessary to mention that the gap 34 can be variable or constant around the perimeter of the cushion.

Fig. 92 illustrates an alternative arrangement to the cushion 10 of Fig. 34A (arrangement of Fig. 34A shown in broken line). As illustrated, some material has been removed from the side wall 28 and the gap 34 has been reduced from the arrangement of Fig. 34A. This arrangement of Fig. 92 increases the offset relative to the previous offset of Fig. 34A. The increased displacement is achieved by changing the geometry of the side wall 28. This arrangement may require that the cross section of the base wall 28 be made thicker to add rigidity around the perimeter of the cushion or locally. Stiffness can be achieved by using local bracing where necessary.

Fig. 93 illustrates an alternative arrangement to the cushion 10 shown in Fig. 15. As illustrated, the hole-shaped cutout area (to receive the patient's nasal bridge region) may be larger as the mask size. For example, the cropped area is larger for an extra-small size mask than a full-size mask.

It should be noted that the cross-sectional pattern of the cushion in specific areas of the patient's face (eg, Figs. 23-29) may be in the specific area or in any area around the perimeter of the cushion. That is, the design of the cross section should not be limited to the specified area. Also, the cross section shown in Figs. 91 and 92 can be used anywhere around the perimeter of the cushion.

Although the invention has been described in relation to what are currently considered the most practical and preferred embodiments, it should be understood that the invention should not be considered limited to the described embodiments; rather the contrary, it is intended to cover different modifications and equivalent arrangements included within the scope of the invention. Furthermore, the different embodiments described above can be implemented in conjunction with other embodiments, for example, aspects of one embodiment can be combined with aspects of another embodiment to achieve other additional embodiments. Furthermore, although the invention has particular application in patients suffering from OSA, it should be appreciated that patients presenting with other ailments (eg, congestive heart failure, diabetes, morbid obesity, strokes, bariatric surgery, etc.) may benefit from the previous teachings. Furthermore, the above teachings are applicable to patients and non-patients alike in non-medical applications.