Patent Application
20240238028
The inventions described below relate to the field of visceral fat reduction.
Visceral fat is found inside the abdominal cavity and wraps around internal organs, as opposed to subcutaneous fat which is stored just below the skin. Visceral fat may be found in the abdomen, under the abdominal muscles. Visceral fat is associated with high blood pressure, increased risk of heart disease, insulin resistance and diabetes, stroke, some cancers, and continued presence in the body may contribute to these conditions.
Various approaches have been attempted to treat visceral fat. Diet and exercise can help eliminate visceral fat. However, diet and exercise are not well-tolerated by the typical overweight patient.
Visceral fat can also be destroyed by cooling to temperatures in the range of +10 C to −40 C. If cooling is limited to this range, surrounding tissue will not be killed. Cryogenically deadened visceral fat will typically be resorbed by the body over the course of a few weeks.
The mechanism of cell death of cooled visceral fat has not been definitively established. It may be due to lysis (disruption of the cell walls), necrosis (death of the cell without disruption of the cell walls) or apoptosis (programmed cell death after injury due to cooling). In prior art methods, regardless of the mechanism of cell death, dead or dying visceral fat cells are left in the body to be resorbed over a period of weeks. This is undesirable.
Liposuction is another treatment to remove fat. Liposuction mechanically disrupts the fat cells and surrounding extracellular matrix, blood vessels, and subsequent aspiration. However, liposuction is relatively violent and limited to the subcutaneous fat.
Accordingly there is still a need for an improved method and system that overcomes the above mentioned shortcomings.
In embodiments of the present invention, a method of reducing visceral fat from a body of a patient comprises thermally treating the visceral fat in the body of the patient sufficient to form a liquid-fat mixture or emulsion. The liquid-fat emulsion is then aspirated.
In embodiments, the treating comprises cooling the visceral fat in situ to a low temperature sufficient to cause the visceral fat cells to freeze, and for the cell membranes to be disrupted, burst or rupture. The low temperature can range from +10 to −40 degrees C. The cooling can be performed for a duration between 10 and 60 seconds, and more preferably, for less than 30 seconds.
In embodiments, cooling is halted for a period of time to allow the fat cells to warm, releasing the contents of the fat cells, thereby forming a liquid-fat mixture or emulsion.
In embodiments, the treating further comprises delivering a warming liquid into the body of the patient at a warm temperature sufficient to thaw the fat cells, thereby releasing contents including lipids into the warming liquid and forming the liquid-fat emulsion. In preferred embodiments, the warming liquid is saline.
In embodiments, the cooling step is performed with a cooling device comprising a handle, a shaft, and a distal treatment section adapted to conduct heat from the visceral fat to cool the visceral fat to the low temperature.
In embodiments, the delivering a warming liquid is performed with a liquid delivery device. The delivery of the warming liquid can be performed for a duration ranging from 1 to 5 minutes within five (5) minutes from the cooling step, or optionally, within two (2) minutes from the cooling step. In embodiments, the warm temperature ranges from 25 to 37 degrees C.
In embodiments, the aspiration step is performed with an aspiration device, and optionally, the aspiration device is integrated with the liquid delivery device.
In embodiments, the method further comprises measuring temperature, and optionally, measuring temperature with a temperature sensor along the distal treatment section of the cooling device. The cooling device can be adjusted or controlled based on the measured temperature.
In embodiments, the treatment is performed on visceral fat, and preferably visceral fat in the mesentery.
In embodiments, the method further comprises visualizing the treatment of the visceral fat, and optionally, wherein the visualizing is performed with a laparoscope.
In embodiments, a surgical system for reducing visceral fat from a body of a patient comprises a cooling device comprising a distal treatment section adapted to conduct heat from the visceral fat to cool the visceral fat; a fluid delivery device for immersing the cooled visceral fat in a warm liquid; and an aspiration device adapted to withdraw the liquid-fat emulsion from the body of the patient.
In embodiments, the system further comprises a controller programmed and operable to (a) control the cooling device according to a cooling temperature profile sufficient to cause the visceral fat cells to freeze and to disrupt the fat cell membrane, and (b) optionally, to control the fluid delivery device to control the warm liquid according to warming temperature profile sufficient to thaw the fat cells, thereby releasing lipids from the fat cells into the warming liquid and forming a liquid-fat mixture or emulsion.
The description, objects and advantages of embodiments of the present invention will become apparent from the detailed description to follow, together with the accompanying drawings.
Before the present invention is described in greater detail, it is to be understood that this invention is not limited to particular embodiments described, as such can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims. Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range, is encompassed within the invention. The upper and lower limits of these smaller ranges can independently be included in the smaller ranges and are also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, representative illustrative methods and materials are now described. It is noted that, as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. It is further noted that the claims can be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation. As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which can be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present invention. Any recited method can be carried out in the order of events recited or in any other order that is logically possible.
All existing subject matter mentioned herein (e.g., publications, patents, patent applications and hardware) is incorporated by reference herein in its entirety except insofar as the subject matter may conflict with that of the present invention (in which case what is present herein shall prevail). The following are incorporated by referenced in their entirety for all purposes: Methods and systems for cooling visceral fat while leaving surrounding tissue unharmed are disclosed in our prior International Patent Publication WO 2020/061202 (published Mar. 26, 2020) and International Patent Publication WO 2021102301 (published May 27, 2020).
Without intending to being bound to theory, in our own studies, we have observed significant liquefaction of visceral fat cells when the fat cells are cooled to the range of −20° C. to −40° C., and thawed. The lipids from the cells appear loose within the tissue, and at a volume and viscosity susceptible to removal by aspiration. This makes it feasible to remove some of the mass of the fat cells, such as this free liquid fraction, without mechanical disruption of the fat cells, by aspiration.
In embodiments, a method of removing visceral fat from the body of a patient comprises the steps of: cooling visceral fat within the body of a patient to a temperature sufficient to cause liquefaction of the visceral fat cells; allowing the cooled visceral fat to warm to a low viscosity susceptible to aspiration, which may be below body temperature or at body temperature (or actively warm it with a warming function of the probe); aspirating a liquid fraction caused by cooling from the body, from the site of liquefaction; avoiding mechanical disruption of the visceral fat and extracellular matrix while performing the cooling and aspiration steps; leaving any remaining solid portion of the visceral fat in the body to be resorbed by the body; and leaving the extracellular matrix and/or blood vessel within the visceral fat in the body.
The step of cooling visceral fat within the body of a patient to a temperature sufficient to cause liquefaction of the visceral fat cells may be accomplished with various cooling methods, examples of which are described herein. Modes may include closed loop or open loop cooling probes or application of cooling packs or even flushing fat with a cold slurry, gas or liquid. A wide range of types of cooling devices (including any cryoprobe, catheter, instrument whether rigid or flexible) capable of cooling the visceral fat to temperatures in the desired range may be used, whether cooled with liquid cryogens or gaseous cryogens, or whether cooled by cold fluid (a gas, liquid or a mixture of gas and liquid, for example), or cooled by expanding gas (argon or nitrogen gas, for example). The cooling probe may be a long, small diameter probe such as a cryoprobe used for freezing tumors. The cooling probe may include expandable cooling structures such as a pad or balloon which may be compacted into an insertion cannula and expanded after insertion to expose a larger portion of visceral pad to cooling. The cooling probe may be inserted, needle-like, without any surrounding cannula or introducer, or a cannula or introducer may be first placed into the visceral fat to provide access, and the cooling probe may then be inserted through the cannula or introducer. This may be preferred if the aspiration step is accomplished with a separate aspiration catheter.
Cooling with a cooling probe is accomplished while controlling the cooling probe to cool visceral fat surrounding the distal end of the cooling probe to temperatures below about −20° C. Preferably, cooling is accomplished while controlling the cooling probe to cool visceral fat surrounding the distal end of the cooling probe to temperatures in the range of −20° C. to −40° C. and controlling the cooling probe to avoid cooling the visceral fat surrounding the distal end of the cooling probe to temperatures below about −40° C., to avoid cryogenic damage to organs, blood vessels and nerves within, or near, the visceral fat.
For visceral fat near the intestines, cooling with a cooling probe may be accomplished while controlling the cooling probe to cool visceral fat surrounding the distal end of the cooling probe to temperatures in the range of about −20° C. to −30° C., and controlling the cooling probe to avoid cooling the visceral fat surrounding the distal end of the cooling probe to temperatures below about −30° C., to avoid cryogenic damage to intestines, which may be more susceptible to damage at colder temperatures.
For large deposits of visceral fat, with some distance from organs, cooling with a cooling probe may be accomplished while controlling the cooling probe to cool visceral fat surrounding the distal end of the cooling probe to temperatures in the range of about −20° C. to −60° C., preferably −40 to −20° C. and controlling the cooling probe to avoid cooling the visceral fat surrounding the distal end of the cooling probe to temperatures below about −60° C., again to avoid cryogenic damage to organs while speeding the cooling process.
In open procedures, flushing the visceral fat with cold fluid such as nitrogen gas may be used to cool the visceral fat. Cooling for a short period of about 30 to 40 seconds has proven sufficient to cool to the temperature ranges mentioned above, but cooling for longer periods may result in a larger zone of liquefaction without harming nearby organs, blood vessels or nerves.
After cooling, the visceral fat may be warmed to a temperature at which liquefaction is evident and the liquid fraction is released from the fat cells. Warming may be passive, using the patient's body temperature to warm the visceral fat, or the warming may be active, using any means for actively warming the visceral fat such as warming fluid flowing through the probe (warm water, or using expanding helium in a Joule-Thompson probe), heating wires within the probe, or RF or microwave energy delivered through the probe.
Upon warming of the visceral fat tissue after cooling, the liquid fraction becomes visible and has a viscosity low enough to remove by aspiration. When this point is reached, the liquid fraction of the visceral fat released by the cooling step is aspirated from the body. Aspiration may be accomplished through the cooling probe, if fitted with an aspiration lumen so that it may be used as an aspiration tube (a catheter, cannula or needle) or with a separate aspiration tube (a catheter, cannula or needle).
Because the visceral fat surrounds other organs and blood vessels and nerves, the method is preferably accomplished without using a means to mechanically disrupt the visceral fat.
The method is preferably accomplished without using the cooling probe, or the separate warming probe, or any other component inserted into the body, to mechanically disrupt the visceral fat (beyond the slight disruption inherent in pushing the cooling probe against the visceral fat). Thus, the method is preferably accomplished without reaming, macerating, dissecting, resecting the visceral fat, or manipulating the cooling probe in direction other than longitudinal translation along the axis of the probe for insertion and removal. The method can be characterized as a gentle or atraumatic thermal treatment.
As the liquid fraction is traveling along the aspiration catheter and tubing, it may cool to ambient, from body temperature, and become more viscous and semi-solid (like butter). Thus, the aspiration catheter and tubing may be provided with a means for warming the catheter and/or associated tubing, such as heating wires or warm water circulation in a jacket surrounding the aspiration catheter. The distal end of the aspiration catheter may be left without means for warming, as it is disposed within the body when in use. Again, the aspiration step is preferably accomplished without reaming, macerating, dissecting, resecting the visceral fat, or manipulating the aspiration catheter in direction other that longitudinal translation along the axis of the probe for insertion and removal.
Step 110 states creating an incision. In embodiments, an incision is made in the skin of the patient to provide access to the abdomen cavity and the visceral fat. In embodiments, the incision is a small keyhole incision suitable for a laparoscope and minimally invasive surgery. In other embodiments, a laparotomy is performed suitable for an open surgery.
Step 120 states advancing an introducer or scope, namely, a laparoscope into the body of the patient. If the physician determines to reduce the visceral fat using a minimally invasive approach, an introducer or perhaps laparoscope is advanced through the incision and the additional treatment steps are performed in combination through the laparoscope or introducer.
However, this step 120 is optional and in embodiments, the incision is made sufficiently large to provide access to the visceral fat, and step 120 is omitted.
Step 130 states cooling the visceral fat. This step may be performed using a cooling probe 4 or a cooling apparatus 210 as described herein and as shown in
The cooling probe or apparatus may be couplable to a controller or console 232 via an umbilical cord. With reference to
In embodiments, and without intending to being bound to theory, the cooling causes the contents within the fat cells to freeze and expand, causing the cell membranes to be disrupted, burst or rupture. Upon thawing, discussed herein, these frozen contents including lipids and liquids are freed.
Step 140 states delivering warm liquid to the site. In a sense, the site is flooded with warm liquid. This step may be performed using the cooling probe 4 when fitted with a fluid delivery channel, or with a separate liquid delivery apparatus 220 as shown in
A minimum volume delivered can be set by the warming 250 to ensure the viscosity mixture is in a range allowing for aspiration. The volume delivered can be monitored based on flowrate, duration, and the controller can halt delivery when a set volume is reached. In embodiments the set volume or maximum volume delivered is limited by the controller to range from 500 to 5000 ml per segment of visceral fat treated.
This may include a set of computer readable instructions or software operable with the processor to turn on and off the fluid delivery apparatus, control its liquid temperature based on real time temperature measurements at one or more locations along the liquid path, control the flowrate of the fluid delivered to the target area, and alert the user to ready status, temperature out of range, time elapsed, service required, etc.
As described herein, the warming liquid serves to warm and thaw frozen cell contents. Upon thawing, these frozen contents including lipids and liquids are freed from the cell. The delivered warm liquid takes up and mixes with the freed cell components, forming a liquid-fat mixture or emulsion. The delivered warming liquid thus serves as a cryo-lipolysis vehicle to accept and transport the lysed matter.
Step 150 states aspirating the liquid-fat mixture. This step may be performed using the cooling probe 4 when fitted with an aspiration channel, or with a separate aspiration apparatus 230 as shown in
In a preferred embodiment, and with reference to
Not shown, the method may comprise displaying on a monitor a wide range of information including, for example, treatment parameters (e.g., cooling time, cooling temperature, thawing time, thawing temperature, aspiration time, number of applications, estimated mixture volume aspirated, estimated fat volume aspirated), status (e.g., offline, ready, cooling, thawing, aspirating, etc.), patient identification information, and a window for a laparoscope or camera view to visualize the treatment in real time.
The following is an example procedure performed on an animal in accordance with an embodiment of the present invention.
Animal type: Ossabaw obese pig.
Fat type: Mesenteric (visceral).
Procedure: A laparotomy was performed to expose the small intestine's mesenteric fat. We used a cooling probe having a round head (2-3 inch in diameter) to spray gaseous nitrogen onto the target area. The temperature of the nitrogen gas was about −40° C. We applied a total of 40 applications (30 second each) to both sides of the mesenteric fat.
A warm saline solution (37° C.) was delivered to the area to thaw the fat following the cooling applications. Approximately 8 freezing cycles were applied to a segment of mesenteric fat before thawing with a warm (100-300 ml) saline solution. We treated the mesenteric fat and thawed with the saline as described above throughout the small intestine. When the freeze/thaw treatment was done, we aspirated the visible saline mixture from the pig which now included both the saline solution and “soluble fat” (or “liquid fat”).
Results: We collected the saline mixture and measured the amount of liquid fat that was removed at the time of the procedure (˜600 ml). We note this is an immediate and acute reduction to the mesenteric fat. The total amount of mesenteric fat in obese Ossabaw pigs is estimated at 3-6 L. Thus, a 600 ml reduction is an approximately ˜10-20% reduction of the overall fat in this anatomical storage region.
We would also expect further fat reduction over several weeks following cryo-lipolysis. Embodiments of the invention include a two phase approach comprising acute/immediate fat removal followed by gradual fat absorption following the initial immediate treatment. In embodiments, a first portion of the visceral fat is treated with an acute/immediate method (e.g., the method 100 described in connection with
While the preferred embodiments of the devices and methods have been described in reference to the environment in which they were developed, they are merely illustrative of the principles of the inventions. The elements of the various embodiments may be incorporated into each of the other species to obtain the benefits of those elements in combination with such other species, and the various beneficial features may be employed in embodiments alone or in combination with each other. For example, the cooling apparatus, liquid delivery apparatus, and aspiration apparatus may be combined together as one instrument or may be separate discrete instruments. Other embodiments and configurations may be devised without departing from the spirit of the inventions and the scope of the appended claims.
This application claims priority to application No. 63/192,545, filed May 24, 2021, entitled “METHOD OF REMOVING VISCERAL FAT.”
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US22/72511 | 5/23/2022 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63192545 | May 2021 | US |
