Patient interface

1. A patient interface for delivering breathable gas to a patient at positive pressure for treatment of sleep disordered breathing, the patient interface comprising:

an interfacing structure including a seal surface configured to sealingly contact the patient's face in use and direct breathable gas to an airway of the patient; and

headgear to support the interfacing structure in a desired position on the patient's head, the headgear comprising a headgear strap,

wherein the headgear strap comprises:

end strap portions; and

an intermediate strap portion between the end strap portions,

the intermediate strap portion including only a single slot which separates the intermediate strap portion into two smaller width straps,

wherein the intermediate strap portion is configured to be movably adaptable between (i) a first configuration in which the two smaller width straps are substantially adjacent to one another, and (ii) a second configuration in which the two smaller width straps are spread apart from one another when the patient interface is worn, thus expanding a width of the slot to allow the intermediate strap portion to conform to the patient's head,

wherein the two smaller width straps include an upper smaller width strap and a lower smaller width strap,

wherein each smaller width strap includes an upper longitudinal edge and a lower longitudinal edge that define a width of the smaller width strap, and

wherein the intermediate strap portion is structured such that when the patient interface is not worn and no external force is applied to the intermediate strap portion, the intermediate strap portion assumes the first configuration where the lower longitudinal edge of the upper smaller width strap is adjacent and substantially aligned with the upper longitudinal edge of the lower smaller width strap.

2. The patient interface according to claim 1 , wherein the intermediate strap portion includes an upper and a lower edge, the upper edge, the lower edge, and the slot extending substantially parallel relative to one another in the first configuration, and

wherein the upper edge of the intermediate strap portion comprises the upper longitudinal edge of the upper smaller width strap, and the lower edge of the intermediate strap portion comprises the lower longitudinal edge of the lower smaller width strap.

3. The patient interface according to claim 1 , wherein the slot extends substantially parallel relative to the end strap portions in the first configuration.

4. The patient interface according to claim 1 , wherein the slot extends substantially parallel to a length of the strap in the first configuration.

5. The patient interface according to claim 1 , wherein each end of the slot includes a stress release hole.

6. The patient interface according to claim 1 , wherein the two smaller width straps have widths that are substantially the same.

7. The patient interface according to claim 1 , wherein the headgear strap comprises a multi-layer construction.

8. The patient interface according to claim 1 , wherein the intermediate strap portion is wider than the end strap portions.

9. The patient interface according to claim 1 , wherein the slot extends along substantially an entire length of the intermediate strap portion.

10. The patient interface according to claim 1 , wherein the intermediate strap portion comprises a substantially planar configuration in the first configuration.

11. The patient interface according to claim 1 , wherein the end strap portions are configured to connect, respectively, to a pair of slotted connectors of the patient interface.

12. The patient interface according to claim 11 , wherein the end strap portions are configured to be adjustably connected to the pair of slotted connectors.

13. The patient interface according to claim 1 , wherein the headgear strap is adapted to pass around a rear portion of the patient's head.

14. The patient interface according to claim 13 , wherein the headgear strap is a rear strap, and said headgear further comprises two side portions and the rear strap is structured to connect the two side portions.

15. The patient interface according to claim 14 , wherein each of the side portions includes a side strap and a rigidizer provided to the side strap to add rigidity to the side strap.

16. The patient interface according to claim 15 , wherein each rigidizer comprises a slotted connector, and each end strap portion is configured to connect to a corresponding one of the slotted connectors.

17. The patient interface according to claim 1 , wherein each of the end strap portions is provided to an elongated rigidizer.

18. The patient interface according to claim 1 , wherein the interfacing structure is adapted to provide a seal with the patient's nose.

19. The patient interface according to claim 18 , wherein the interfacing structure comprises a nasal prong assembly including a pair of nasal prongs.

20. The patient interface according to claim 18 , wherein the interfacing structure comprises a nasal cradle.

21. The patient interface according to claim 13 , wherein the intermediate strap portion is configured to assume the second configuration upon engagement with the rear portion of the patient's head.

22. The patient interface according to claim 1 , wherein the end strap portions are configured to extend over respective sides of the patient's face when the patient interface is worn.

23. The patient interface according to claim 22 , wherein, when the patient interface is worn, the intermediate strap portion is configured to extend around a rear portion of the patient's head.

24. The patient interface according to claim 23 , wherein, when the patient interface is worn, the intermediate strap portion is configured such that the slot does not extend over a portion of the patient's face anterior of the patient's ears.