Formulations, devices, and methods for alleviating symptoms of ocular surface discomfort
Disclosed herein are cold slurry formulations, devices, and methods for alleviating symptoms of ocular surface discomfort. Cold slurry formulations comprising ice, a freezing temperature depressant, and, optionally, a lipid are disclosed. Devices and methods for protecting a target ocular surface from contacting a cold slurry formulation that is used to maintain the target ocular surface at a temperature desired for alleviating symptoms of ocular surface discomfort are disclosed. Self-contained devices configured to receive a cold slurry formulation for maintaining the target ocular surface at a temperature desired for alleviating symptoms of ocular surface discomfort are disclosed. Devices and methods are disclosed for protecting a cornea and/or eyelid of a subject from the freezing cold slurry formulation that is directly or indirectly applied or injected into the target ocular surface. Kits comprising multiple syringes for administering multiple doses of the cold slurry to the target ocular surface, are disclosed.
1 . A self-contained cooling device for cooling a target tissue surface of an ocular surface of a subject, the self-contained cooling device comprising:
a formulation chamber comprising a hollow chamber with an open end, wherein the formulation chamber is configured to receive and hold a cold slurry formulation having a plurality of ice crystals;
a lid configured to fit over and seal the open end of the formulation chamber; and
a target surface interface comprising a first surface configured to contact the target tissue surface and a second surface configured to be contained within the formulation chamber,
wherein the target surface interface is configured to conduct heat from the target tissue surface to the cold slurry formulation within the formulation chamber; and wherein the outer dimensions of the first surface are configured to remain substantially the same when the self-contained cooling device is cooling the target tissue surface, and
wherein the outer dimensions of the first surface remain substantially the same before contacting the first surface to the target tissue surface, during treatment, and after removal of the first surface from the target tissue surface.
2 . The self-contained cooling device of claim 1 , wherein the self-contained cooling device is configured to maintain the ocular surface at a temperature suitable for reducing ocular surface discomfort.
3 . The self-contained cooling device of claim 1 , wherein the first surface is configured to contact a sclera of the ocular surface.
4 . The self-contained cooling device of claim 1 , wherein the target surface interface comprises an opening configured to fit over a cornea of the ocular surface to avoid contact between the target surface interface and the cornea when the target surface interface is in contact with the ocular surface.
5 . The self-contained cooling device of claim 1 , wherein the second surface has a curved surface.
6 . The self-contained cooling device of claim 1 , wherein the target surface interface is configured to promote uniform cooling of the target tissue surface when the formulation chamber is filled with the cold slurry formulation.
7 . The self-contained cooling device of claim 1 , wherein the target surface interface comprises thermally conductive materials selected from the group consisting of Al, Cu, stainless steel, metal alloys, and combinations thereof.
8 . The self-contained cooling device of claim 1 , wherein the first surface of the target surface interface comprises a surface coating that protects the target tissue surface from adhering to the target surface interface.
9 . The self-contained cooling device of claim 1 , wherein the first surface of the target surface interface comprises a geometric design feature that protects the target tissue surface from adhering to the target surface interface.
10 . The self-contained cooling device of claim 9 , wherein the geometric design feature comprises one or more of a hierarchical microstructure, a hierarchical nanostructure, a bioinspired surface pattern, or a combination thereof.
11 . The self-contained cooling device of claim 1 , wherein the first surface of the target surface interface comprises a low surface energy material.
12 . A self-contained cooling device for cooling a target tissue surface of an ocular surface of a subject, the self-contained cooling device comprising:
a housing;
a heat exchanger, wherein the heat exchanger comprises a formulation chamber configured to receive and hold a formulation, wherein the formulation is configured to freeze to a subzero temperature in a cold environment;
an aperture, wherein the aperture is configured to allow a clinician to visualize a cornea of a subject; and
a target surface interface comprising a first surface configured to contact the target tissue surface and a second surface configured to be contained within the formulation chamber, wherein the target surface interface is configured to conduct heat from the target tissue surface to the formulation after the formulation has been frozen to a subzero temperature within the formulation chamber.
13 . The self-contained cooling device of claim 12 , wherein the cold environment is a standard freezer.
14 . The self-contained cooling device of claim 12 , wherein the formulation comprises water and a freezing point depressant.
15 . The self-contained cooling device of claim 14 , wherein the freezing point depressant is at a concentration of about 20% (wt/wt).
16 . The self-contained cooling device of claim 14 , wherein the freezing point depressant is glycerol.
17 . The self-contained cooling device of claim 12 , wherein the first surface is configured to adhere to the target tissue surface upon contact.
18 . The self-contained cooling device of claim 12 , wherein the target tissue surface is a sclera of the ocular surface.
19 . The self-contained cooling device of claim 18 , wherein the sclera is adjacent a corneal limbus.
20 . The self-contained cooling device of claim 12 , wherein the subzero temperature is between about −20° C. and about 0° C.
21 . The self-contained cooling device of claim 12 , wherein the target surface interface comprises thermally conductive materials selected from the group consisting of Al, Cu, stainless steel, metal alloys, and combinations thereof.
22 . The self-contained cooling device of claim 12 , wherein the self-contained cooling device is configured to be used with an accessory.
23 . The self-contained cooling device of claim 22 , wherein the accessory is a speculum.
24 . The self-contained cooling device of claim 22 , wherein the accessory is configured to hold open an eye of the subject.
25 . The self-contained cooling device of claim 22 , wherein the accessory is configured to protect an eyelid of the subject from subzero temperatures.
26 . The self-contained cooling device of claim 22 , wherein the accessory comprises silicone.
27 . The self-contained cooling device of claim 12 , wherein the self-contained cooling device is further configured to receive a cap, wherein the cap is configured to prevent condensation from forming on the target surface interface prior to a procedure.
28 . A method of alleviating symptoms of ocular surface discomfort, the method comprising:
cooling a self-contained cooling device containing a formulation, wherein the formulation is configured to at least partially freeze when cooled,
placing the self-contained cooling device in contact with a target ocular surface,
allowing the self-contained cooling device to lower the temperature of the target ocular surface for a period of time sufficient to alleviate symptoms of ocular surface discomfort;
wherein the self-contained cooling device comprises a housing, a heat exchanger, wherein the heat exchanger comprises a formulation chamber configured to receive and hold the formulation, an aperture, wherein the aperture is configured to allow a clinician to visualize a cornea of a subject, a target surface interface comprising a first surface and a second surface, wherein the first surface is configured to contact the target ocular surface and the second surface is configured to be contained within the formulation chamber.
29 . The method of claim 28 , wherein the target surface interface is configured to adhere to the target ocular surface upon contact.