Simple Closed Loop System for Direct Harvest and Transfer for High Volume Fat Grafting

Abstract

This invention proposes the construction of a simple closed loop system for continuous flow harvesting, collection, syphoning, and grafting of large volumes of fat. (See FIG. 1—a schematic of the overall setup). This invention uniquely bypasses the standard cumbersome and time-consuming process, that mainly being the need to first transfer fat into individual syringes prior to grafting into the patient. This is traditionally done with unmeasured, manual pressures as generated by a simple plunger syringe. It can be messy and sloppy, with loss of fat. In contrast, this innovative concept presented here simplifies the whole process into a closed loop, from the donor harvest site, and then back to the patient. The concept is modular, drawing on commonly used, interchangeable parts and pumps present and available in most basic community hospital operating rooms. The major benefit is a significant reduction in time to transfer. However there is also a simplification of the process with less air exposure time, consistent controlled limit on flow pressures, and a simple on off control that can be held in one hand. The system is adaptable to standard liposuction and introduction cannulas through standard liposuction tubing and a luer lock connection. Collection canisters are also interchangeable.

Description

BRIEF DESCRIPTION OF FIGURES & DRAWINGS

FIG. 1: Sketch of Invention “A Simple Closed Loop System for Direct Harvest and Transfer for High Volume Fat Grafting”. This Figure is a labeled outline sketched by myself, showing the separate components for the system and how they are connected together with respect to the flow and direction of the fat harvesting.

FIG. 2: Photograph of a sample set up in the operating room, with all the components connected to build the Loop System. There is a lipo-aspirate harvesting cannulas (large at bottom) and smaller fat introduction cannulas directly attached (center). The collection canister is seen top center, and pump component is on the upper left.

FIG. 3: Sample of simple clamp used to control flow of transferred fat. The operators hand used to introduce the fat can easily operate the clamp.

FIG. 4: Photo of a pulsatile pump that is loaded and charged with fat in tubing for transfer.

BACKGROUND

Fat grafting as an adjunct for contour modulation in breast reconstruction has become fairly commonplace^1-3 since The American Society of Plastic Surgeons lifted a ban on fat grafting to the breast in 2009. Optimal methods and techniques of transfer and fat handling has become a hot area of research and technological development. Many techniques involve the transfer of fat back into the breast via a hand held 60 cc syringe powered by manual plunger. Recently, Khouri^4,5 has championed ‘megavolume fat transfer’ for breast reconstruction, designating mega as >300 cc per breast. Extrapolating this process to two breasts would necessitate at least ten 60 cc syringes. Transferring fat into syringes and refitting the plungers is tedious. Small amounts of fat may be spilt or lost with the filling each syringe. Multiplying by ten syringes adds up to wasted viable tissue. Manually forcing the plunger after already performing manual or assisted liposuction is tiresome on the hands. A technique to streamline this process, bypassing the syringe step and supplying a gentle controlled pressure for infusion saves precious operating time and anesthesia time for the patient, allows controlled flow and minimizes the time the graft is out of the patient. It also relieves significant wear and tear on a surgeon's hands.

METHOD

See FIG. 3: Photograph of all 3 Components Connected as One System—Harvesting, Processing and Transfer

1. Fat Harvest:

This may be done through a variety of techniques but basically any standard or preferred liposuction cannulas, connecting the liposuction tubing to a canister reservoir with an outflow luer lock, such as the JAC Cell®, Revolve®, or other sterile collection system.

2. Processing:

This may be done through the surgeons preferred technique, depending on the canister system used. If the JAC cell is used than the aqueous layer is allowed to decant and is first syphoned off through the luer lock connection.

3. Fat Transfer:

A pulsatile pump, with upper pressures limited to 150-350 mm HG, is then connected to the outflow valve of the fat collection canister. For example the Arthrex® Pump with slightly wider bore tubing works well without clogging, but other tubing as well can be adapted. The two ends of the tubing remain on the operative field with sterility preserved. The tubing can be directly connected to most standard fat transfer cannulas. A simple clamp (see FIG. 3) on the tubing allows the operator to control the flow of the fat and introduction all with one hand, while the other hand is free to palpate tissue turgor, contour and position of the recipient bed or breast. (See FIG. 4 example of fat loaded and flowing through pump)

REFERENCES

• 1. Spear S L, Wilson H B, Lockwood M D. Fat injection to correct contour deformities in the reconstructed breast. Plast Reconstr Surg. 2005; 116:1300-1305.
• 2. Coleman S R, Saboeiro A P. Fat grafting to the breast revisited: Safety and efficacy. Plast Reconstr Surg. 2007; 119:775-785;
• 3. Delay E, Garson S, Tousson G, Sinna R. Fat injection to the breast: Technique, results, and indications based on 880 procedures over 10 years. Aesthet Surg J. 2009; 29:360-376.
• 4. Khouri R K, Rigotti G, Cardoso E, Khouri R K Jr, Biggs T M. Megavolume autologous fat transfer: Part I: Theory and Principles. Plast Reconstr Surg. 2014; 133:550-557.
• 5. Khouri, Roger K. M.D.; Rigotti, Gino M.D.; Cardoso, Eufemiano M.D.; Khouri, Roger K. Jr. B. S.; Biggs, Thomas M. M.D. Megavolume Autologous Fat Transfer: Part II. Practice and Techniques. Plast Reconstr Surg. 2014; 133:1369-1377.

Claims

1. A method of harvesting and transferring large volumes of fat for grafting in a sterile closed circuit system, wherein the method:

a) Saves operating and anesthesia times

b) Limits spillage and waste of graft tissue

c) Decreases manual force needed

d) Decreases strain and fatigue on the surgeon's hands,

e) Limits air exposure of graft material.

f) Moreover the system can be built using multiple interchangeable components already in use in various aspects of fat grafting and fluid transfer, but their utilization together as a system provides a time and facility benefit greater than the sum of the parts alone.