Patent Publication Number: US-9421125-B2

Title: Head cooler

Description:
This application is a Divisional of U.S. Ser. No. 12/525,744, filed 4 Aug. 2009, which is a National Stage Application of PCT/EP2008/051890, filed 15 Feb. 2008, which claims benefit of Serial No. 0700374-2, filed 15 Feb. 2007 in Sweden and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a head cooler to be arranged at the head of a person undergoing treatment of cytostatics. 
     BACKGROUND OF THE INVENTION 
     A human being undergoing treatment with cytostatics (chemotherapy) or similar treatment often suffers from loss of hair. By maintaining, during the treatment, a low temperature on/at/of the hairy region, usually the scalp, such a loss can be eliminated or substantially reduced. 
     A head cooler disclosed in U.S. Pat. No. 6,156,059 comprises a head cover to be placed over a human scalp for enclosing the patient&#39;s head and neck. Flow passages, through which a cooling fluid is flown, are provided in the cover which forms an inside heat exchange surface to be applied against the scalp for cooling the scalp. A temperature sensor is mounted in connection with each flow passage for registering the local temperature. 
     The size and shape of heads of different patients may vary a lot. If the head cooler is too large or too wide, a gap may be formed between the heat exchange surface and the head. Then, the cooling of the scalp may be jeopardized, since the heat exchange surface is not held in contact with the scalp over the entire surface thereof. As a consequence the cooling efficiency will be reduced in the area of the gap resulting in loss of hair. 
     It is proposed according to the Japanese Patent Abstract of Patent Application No. 6270060 to mount to the inside surface of the head cover a plurality of bag bodies to which a pressure fluid is supplied in order to press a heat exchange surface against the patient&#39;s head and neck for cooling the scalp. 
     A drawback with currently used head coolers is that the head cover is not easily adaptable to the size and/or shape of the patient&#39;s head and neck, which may result in a too low or an impaired cooling efficiency. 
     Another disadvantage is that the currently presented head coolers do not involve the cooling of the eyebrows or the region of the eyebrows. Loss of the eyebrows is also considered to be a problem for patients undergoing treatments with cytostatics. 
     DISCLOSURE OF THE INVENTION 
     An object of the present invention is to eliminate or alleviate at least one of the drawbacks mentioned above, which is achieved by assigning to the device the characteristics according to claim  1 . 
     According to one aspect of the invention, there is provided a head cooler comprising a thermal exchange cap to be arranged on the head of a patient, and at least one flow passage system for a cooling fluid provided in the thermal exchange cap forming an inside heat exchange surface to be applied against the head for cooling of the head. The thermal exchange cap is adaptable and/or adjustable to compensate for a discrepancy, if any, as to shape and size between the inside surface of the head cooler and the head. 
     The head cooler further comprises an outer insulating cover made of a heat insulating material, e.g. also elastic, which encloses the thermal exchange cap. The head cooler comprises means for filling up, by the supply of a fluid heat conducting material, a gap between the inside surface of the thermal exchange cap and the head. 
     According to one embodiment, the thermal exchange cap is partitioned into sections that are engageable at adjacent edge portions. The sections are mutually overlapping and are slidable against each other, and are oppositely bevelled in the transverse direction. Each section has at least one flow passage system for the cooling fluid. The cross sections of the flow passages are wedge shaped, circular, semi circular, rectangular, elliptical, square or of any other shape. The partitioned sections have a common inlet and/or outlet flow passage or a separate inlet and/or outlet flow passage for the cooling fluid. A flow passage extends along each side of the partitioned sections, which converge to a common location on the thermal exchange cap, preferably at the top, and extend into an opening on said location. 
     The filling up means comprises at least one external connection on the thermal exchange cap communicating with a space between the inside of the thermal exchange cap and the scalp. 
     According to another embodiment the head cooler further comprises an inner head cover consisting of a flattened bag of flexible material, which can be inflated, forming a lining on the inside of the thermal exchange cap. The bag forms a single cavity or multiple cavities. At least one valve or other means, such as a tube, is provided between a cavity of the bag and the flow passage system for supplying cooling fluid from said system to the bag cavity/cavities. 
     Means are provided for controlling the flow of the cooling fluid. A connection is provided for supplying air or a gas or a gas mixture (under pressure) to the flow passage system or to the cavity or cavities to evacuate the cooling fluid from the bag. 
     According to an alternative embodiment, the head cooler is complemented by an eyebrow cooler comprising a flattened bag of flexible material, which can be inflated. The bag forms a single cavity or multiple cavities, at least one valve or other means, such as a tube, is provided between the cavity of the bag and a flow passage system for supplying a cooling fluid from said system to the bag cavity/cavities. 
     According to a second aspect of the invention, a use of a head cooler is provided for preventing hair loss during chemotherapy treatment. 
     Further objects, features and advantages of the present invention will appear from the following detailed description, from the attached drawings as well as from the dependent claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to explain the invention, a number of embodiments of the invention will be described below with reference to the drawings, in which: 
         FIG. 1  is a perspective view of a head cooler according to the invention, which is in use with a patient, 
         FIG. 2  is a side view of the head cooler in  FIG. 1 , 
         FIG. 3  is a side view of the head cooler in use, but shown without the outer insulating cover, 
         FIG. 4  is the head cooler in  FIG. 3  provided with additional tubes, 
         FIG. 5  is a side view of the head cooler in  FIG. 4  during injection of a fluid filling up a gap between the heat exchange surface of the thermal exchange cap and the scalp, 
         FIG. 6  is a side view of a partitioned thermal exchange cap, wherein the sections are shown separated, 
         FIG. 7  is a side view of the cap in  FIG. 6  with the sections closed and interconnected, 
         FIG. 8  shows the thermal exchange cap in  FIG. 6  provided with additional tubes, 
         FIG. 9  shows the thermal exchange cap in  FIG. 7  provided with additional tubes, 
         FIG. 10  is a frontal perspective view of an inner head cover having a cavity provided at the top thereof, 
         FIG. 11  is a perspective view of the inner head cover of  FIG. 10  from behind, 
         FIG. 12  shows the inner head cover in  FIG. 10  provided with additional tubes, 
         FIG. 13  shows the inner head cover in  FIG. 11  provided with additional tubes, 
         FIG. 14  is a frontal schematic view of an eyebrow cooler, 
         FIG. 15  is a perspective view of the eyebrow cooler in  FIG. 14 , 
         FIG. 16  is a perspective view of the eyebrow cooler in  FIG. 15  from behind, 
         FIG. 17  shows the head cooler in  FIG. 1  provided with an eyebrow cooler and an insulating eyebrow cover in raised position, and 
         FIG. 18  shows the head cooler according to  FIG. 17  with the insulating eyebrow cover in lowered position. 
     
    
    
     Same reference numerals have been used to indicate the same parts in the figures to increase the readability of the description and for the sake of clarity. 
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     A head cooler  10  according to one embodiment of the invention comprises a thermal exchange cap  11  and an outer insulating cap  12 , as shown in  FIGS. 1 and 2 . The outer insulating cover is fitted over the thermal exchange cap to stabilize the cap on the patient. The outer cover is made of a heat insulating and elastic material, e.g. neoprenes of the type used in diving suits, to heat insulate the thermal exchange cap against the surroundings. 
     A chinstrap  13  can improve the stabilization of the outer insulating cover. A first end of the strap is attached to the lower margin at one side of the outer cover and a second end of the strap, which is provided with a Velcro type fastener for adjustable and releasable connection, is attached at the other side of the outer cover. 
       FIGS. 3, 4 and 5  show the head cooler without the outer insulating cover. The thermal exchange cap  11  is made of a flexible and preferably elastic material, such as silicone rubber of medical grade, to fit tightly over the head and neck of a patient. The thermal exchange cap forms internal partitions, which can be made from the material of the cap and which define two channel systems, a first one  31  extending over the forward portion of the thermal exchange cap and a second one  32  extending over the neck portion of the thermal exchange cap. Flexible hoses  33  and  34  are connected to inlets  35  and  36  of the cap, communicating with the channel systems  31  and  32 , respectively. An outlet  37 , communicating with the both channel systems  31  and  32 , is connected with a flexible hose  38 . The hoses  33 ,  34 ,  38  are connected with an external device (not shown) for circulating a cooling fluid through the channel systems, and means are provided for controlling the flow of the cooling fluid. Since the front part of the head emits more heat than the back part of the head, the flow in the forward portion, i.e. in the first channel system  31 , may be higher than in the neck portion, i.e. in the second channel system  32 . Alternatively, the temperature of the cooling liquid may be lower in the forward portion than in the neck portion. 
     The two channel systems  31  and  32  may be of a meander shape, a labyrinth shape, and/or maze shape, as disclosed in  FIGS. 3 to 6 . These shapes maximize the exchange surface against the head. It is also preferable to have the substantial extension of the channel systems  31  and  32  in the direction around the head, i.e. in a plane substantially perpendicular to the anteroposterior axis of the patient. In this way blood vessels in the head, having a substantial anterior direction, will be crossed by the flow of cooling liquid in an early phase of the cooling procedure, while the cooling ability of the cooling liquid still is high, assuring that substantially all the blood will be heat exchanged with the head cooler. Also, it is believed that the pressure to be applied may be minimized, since the cooling liquid only has to travel once from the inlet to the top of the head in a net anterior direction, i.e. upwards during use. 
     It is also preferable to have the inlets  35  and  36  in the posterior end of the head cooler, such as disclosed in  FIG. 3 . Thus, the cooling liquid circulating in the head cooler will substantially move in a plane substantially perpendicular to the anteroposterior axis of the patient, while traveling from the posterior end to the anterior end of the head cooler by the stepwise elevation in the meander shaped, labyrinth shaped, and/or maze shaped channel systems  31  and  32 . In this way the warm blood to be cooled will be heat exchanged with cooling liquid of high cooling ability in a net parallel heat exchange, resulting in a more higher heat exchange effect posteriorly. A high heat exchange effect posteriorly is beneficial, since it then can be assured that the blood entering the scalp has an initial high temperature drop. 
     The present invention may been realized by moulding the head cooler in two pieces of the flexible and preferably elastic material, such as silicone rubber of medical grade, wherein a first piece, for example the piece intended to be closest to the skull during use, may be moulded with the channel systems by forming ribs shaping the channel systems, while a second piece, for example the piece intended to be closest to the surroundings during use, may be a substantially flat piece. Thereafter, the first and second pieces are attached to each other by for example providing the ribs on the first piece with glue and then apply the second piece thereon, whereby the first piece and the second piece will be glued together while forming the channel systems  31  and  32  in space in between the ribs. It has up to this point not been possible to shape channel systems in head coolers in this way, whereby it has not been possible to manufacture head coolers with integrated meander shaped, labyrinth shaped, and/or maze shaped channel systems. 
     Any other arrangement than that described herein can be provided for circulating the cooling fluid through the channel systems, for example the channel systems can have separate outlets, or the two channel systems can be interconnected, thus forming a single system having a single inlet. Alternate embodiments can comprise one system or more than two systems. The cross sections of the flow passages of the channel systems can be of any shape, e.g. circular, semi circular, elliptical, triangular, rectangular, square or wedge Shaped. The thermal exchange cap, as shown in  FIGS. 3 and 4 , comprises two hollow studs  39  for insertion of temperature sensors for measuring the temperature on or close to the surface of the scalp in the regions of the channel systems  31  and  32 , respectively. The sensors can be operatively connected with the device circulating cooling fluid through the channel systems for controlling the flow of cooling fluid and the temperature of the related region of the scalp in dependence of the temperature sensed. 
     The cap comprises an additional hollow stud  41  for the insertion of a safety temperature sensor for measuring the temperature on or close to the surface of the scalp. The safety temperature sensor senses the temperature in an independent position on or close to the scalp, in relation to above mentioned stud(s)  39 , and is operatively connected with the device for circulating cooling fluid, in order to shut off said device, e.g. if the temperature on or close to the scalp sinks below a set temperature to avoid frost injury. 
     In an alternate embodiment the studs may be omitted, or only one stud or more than two studs may be provided. 
     As explained above, there may be a discrepancy between the size and shape of the patient&#39;s head and neck and the size and shape of the thermal exchange cap, resulting in a gap between the inside of the heat exchange cap and the scalp. This may jeopardize the efficiency of the cooling of the patient&#39;s scalp, since the inside surface of the cap, i.e. the heat exchange surface, partially is not in contact with the surface of the scalp. 
     In order to allow compensation for the discrepancy in shape, there can be provided, on the crown of the thermal exchange cap, a further hollow stud  42  to which an injection syringe  43  can be connected for the injection of a heat conducting material  44  into the gap, as illustrated in  FIG. 4 . Suitable materials for this purpose are e.g. gels, hydro gels, liquids, such as water or cooling liquid, and pastes. The material can include an additive, for example a blood vessel contracting substance, such as nicotine, and/or a heat conducting material, such as a salt or a metal. The stud  42  can be located in another position than that shown in  FIG. 4 , and additional hollow studs  40  can be provided in other positions on the cap, e.g. for inserting additional tubes A, B, which will be explained below. 
     To compensate for the discrepancy in size of head and neck, another embodiment of the thermal exchange cap  60  is provided, as shown in  FIG. 6 . The thermal exchange cap  60  is partitioned into two sections  61  and  62 , and has mutually overlapping edge portions sliding against each other. The edge portions may be oppositely bevelled in the transverse direction thereof to reduce the material thickness at the overlapping site. The cap has inlets  63  and  64 , which are arranged to the sections  61  and  62 , respectively, and are in communication with flow channels for circulating the cooling fluid through the flow channels, as described above. An outlet  65  is provided for recirculation of the cooling fluid back to the cooling device. A device  70  is arranged for interlocking the sections of the cap, taking into account different head sizes and also for the purpose of forming the smallest possible air gap between the inside surface of the thermal exchange cap and the patients head. A hole or an opening  71 , for example substantially circular or elliptical, is provided on the top of the cap, or at the point where the sections converge, to avoid a cone-shaped deformation of the cap. 
     To further improve the adaptation of the thermal exchange cap to the size of the head and neck of the patient, the flow passages from the inlet may be arranged along each defined side of the partitions of one or more sections, from the lower margin of the cap to the top of the cap, or further to the opposite lower margin, to avoid one or more gaps between the thermal exchange cap and the scalp at arrangement on the head of the patient. The flow passages may have a wedge shaped, a rectangular or a semi circular cross section having the base member or broadest member arranged against the head of the patient to improve the adaptation of the cap to the head. 
     According to alternative embodiments, the thermal exchange cap may be partly partitioned into one section or fully partitioned into several sections, which converge to a point and extend into an opening. Furthermore, each section may have one or several inlets and one or several outlets, and may have multiple channel systems, which may be separated from each other or interconnected using or not using same inlet(s) and/or outlet(s). 
     Supplementary holes, not shown, may be provided on the inside and/or outside of the thermal exchange cap  11  and  60 , which will be explained in detail below. The holes may be provided with valves or tubes. 
     The thermal exchange cap according to any of the described embodiments may have elevated ridges (not shown) arranged on the exterior surface in order to form air gaps between the thermal exchange cap and the outer insulating cover  12 , when arranged on the head of a patient. 
     To further improve the cooling efficiency of the head cooler, there is provided an inner head cover  100  to be arranged on the patients head under the thermal exchange cap  11 ,  60 , as a lining thereof. The inner head cover comprises a flattened bag made of one sheet, or two or several superposed sheets, of flexible elastic or not elastic plastic material or other material, which is/are welded, glued, stitched or in any other way joined forming one cavity or multiple separated cavities in the inner head cover. One or several holes  102 , provided or not with valves  103 , is/are arranged into the cavity or the multiple cavities to allow inlet of a circulating cooling fluid via tubes A, B, as shown in  FIGS. 12 and 13 , from a cooling fluid source for filling up the cavity or cavities in order to minimize the air gap between the patients head and the thermal exchange cap  11 ,  60 , and hence for improving the thermal conduction between the patients head and the thermal exchange cap. Similarly, the holes  102  provided with or without valves or tubes A, B allow outlet of the cooling fluid for recirculation of the fluid back to the source. 
       FIGS. 10 and 11  show the inner head cover  100  having a cavity  101  formed on the top thereof, wherein the cavity has at least two holes  102  provided with valves  103 . Alternatively, tubes A, B may be arranged to the holes  102 , as illustrated in  FIGS. 12 and 13 . A chin strip  104  of plastic material is arranged to the lower margin of the inner head cover for securing the inner cover to the patient. 
     In a further embodiment the cavity (or cavities) of the inner head cover  100  communicates (communicate) with the channel systems of the thermal exchange cap  11 ,  60  by the holes  102 , which are connected to the additional holes  40  of the thermal exchange cap  11 ,  60  via the valves  103 , thus the channel systems of the cap supply the cooling fluid to the inner head cover. The supply can be performed continuously during the treatment, or instantly before start of the treatment. In the latter case the valves will be closed when the cavity/cavities is/are filled. Alternatively, the cavity is filled with cooling fluid via tubes A, B connected to at least one of the hoses  33 ,  34 ,  38 , or by injecting the fluid by a syringe or another means. Furthermore, the cavity or cavities can be filled with a cooling fluid before placing the cover on the head of a patient. The valves  103  may be of different types, for example pressure regulating valves, non return valves, etc. 
     One or several additional sealable or not sealable openings may be provided on the inner head cover for injection of a gel or other fluid having appropriate viscosity in order to minimize air gaps between the thermal exchange cap and the patient&#39;s head, for further improving the thermal conduction there between. 
     A connection device for an emptying tube or emptying valve may be coupled to the hoses  34 ,  35 ,  38  mounted to the channel systems of the thermal exchange cap  11 ,  60 , in order to inflate the cavity/cavities of the inner head cover by air or gas or a gas mixture of atmospheric pressure or overpressure, or deflate the cavity/cavities by vacuum, in order to evacuate the remaining cooling fluid of the cavity/cavities after finished treatment. In some cases it may be possible to evacuate the cavity/cavities simply by the channel systems via a tube using gravitation. 
     In the embodiments described, there are several flow passages or channels in the thermal exchange cap for the cooling fluid, but it is also possible to have a single space or several spaces interconnected with each other, through which space/spaces the cooling fluid is passed between the fluid inlet and the fluid outlet. 
     The head cooler according to the embodiments described above can be complemented with an eyebrow cooler  140  for cooling the eyebrows of the patient, as shown in  FIGS. 14, 15 and 16 . The eyebrow cooler is made of a flexible and preferably elastic material, such as silicone rubber or plastic material of medical grade, to be adapted closely to the forehead of a patient. The eyebrow cooler comprises a flattened bag made of one sheet, or two or several superposed sheets, which is/are welded, glued, stitched or in any other way joined forming one cavity or multiple cavities. Hoses  142  are connected to the eyebrow cooler at a first end, and are in communication with the cavity or cavities to allow inlet and outlet of a circulating cooling fluid. The second ends of the hoses  142  can be connected to the hoses  33  and  34 , respectively, which are coupled to a cooling fluid source, or the ends can be coupled directly to the cooling source. The eyebrow cooler may comprise one or several hollow stud(s) (not shown) for the insertion of one or more temperature sensors for controlling the temperature at the area of the eyebrow cooler  140 . 
     The eyebrow cooler can be used in combination with the head cooler as shown in  FIGS. 17 and 18 , or separately.  FIG. 17  shows a patient having an eyebrow cooler  140  arranged tightly over the eyebrows and a head cooler  10  arranged on the head. The hoses  142  are arranged under the outer insulating cover  12 . An eyebrow cooler cover  170  is provided to be arranged over the eyebrow cooler  140  for insulation against the surrounding air, and is shown in a raised position in  FIG. 17  and in a lowered position in  FIG. 18 . 
     Holes, provided or not with valves, can be arranged into the cavity or the multiple cavities of the eyebrow cooler  140  for circulation and recirculation of the cooling fluid via external hoses in direct communication with the fluid source. Also, the eyebrow cooler can be filled with a cooling fluid before arranging it over the patient&#39;s eyebrows. 
     The head cooler described above is provided for use in medicine, and more specifically for preventing hair loss during chemotherapy treatment. A method for preventing hair loss on a patient is also provided by arranging the head cooler on the head of said patient. 
     Furthermore, the head cooler described above is provided for use in medicine, and more specifically for the treatment of patients suffered from stroke. The cooling of the head of stroke patients alleviates the damage caused by the stroke. A method for treatment of patients suffered from stroke is thus also provided by arranging the head cooler on the head of said patient. 
     In the claims, the term “comprises/comprising” does not exclude the presence of other elements or steps. Furthermore, although individually listed, a plurality of means, elements or method steps may be implemented. Additionally, although individual features may be included in different embodiments, these may possibly be combined in other ways, and the inclusion in different embodiments does not imply that a combination of features is not feasible. 
     In addition, singular references do not exclude a plurality. The terms “a”, “an” does not preclude a plurality. Reference signs in the claims are provided merely as a clarifying example and shall not be construed as limiting the scope of the claims in any way.