In Asia, young patients undergo pan-facial fat injection for facial contouring rather than rejuvenation. Although the procedure is widely performed, there is no singular approach that has been shown to have consistent results. The author’s approach based on the facial fat compartment theory is presented here. The injection area is classified into functional zones and transition zones. A retrospective review was performed to evaluate the effectiveness of this approach. Satisfactory results were achieved in 96% of cases. In the author’s view, this approach is safe, easy to learn, and produces satisfactory stable aesthetic results based on the facial fat compartments.
Key points
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The author introduces a fat injection approach for facial contouring of young Asian women.
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This method is based on the theory of facial fat compartments, and goal is to distribute facial highlights and shadows needed by Asian women.
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The approach includes the choice of incision, level of injection, and quantity of injection needed in different parts, named as functional zones and transition zones.
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At the present time, this approach has achieved very stable and satisfactory results in the author’s clinical practice.
Video content accompanies this article at http://www.plasticsurgery.theclinics.com .
Introduction
Facial fat injection is a common procedure worldwide. It is widely used in facial rejuvenation, soft tissue augmentation, and other applications. However, the procedure is not considered to have consistent results and no single procedure is widely accepted. The fates of the injected fat grafts are also not certain. Some authors argue that the fat should be injected into fat pad, whereas others think it should be injected into the muscle. Each option has its advantages and has produced good results, but none have earned the full confidence of the medical community.
The facial fat compartment theory supports a promising method. Drs Rohrich and Pessa have brought the concepts of fat deposition and smooth transition between compartments to plastic surgeons’ attention. The first author of the current work, who completed his fellowship in 2008 at UT Southwestern, learned a great deal about fat injection from these 2 researchers. After returning to China, the author gradually developed a personal pan-facial injection approach based on their findings. A classification method based on Asian aesthetic goals was here used to guide the deposition volume. Over the past 6 years, as more consistent results have been achieved, the approach was considered fully developed, and major revisions ceased. In this article, the details underlying this approach are presented and the results are reviewed.
Preoperative evaluation and special considerations
All patients desired pan-facial fat injection to improve their facial contouring. All patients were female. Before surgery, I discuss with patients about the injection areas, possible complications and considerations during recovery period. For some hesitant patients, I also choose to use 3-dimensional simulation to help them determine whether the effect after surgery is consistent with their expectations. I point out the location where the skin will be pierced. The planned harvested area of lateral thigh is also evaluated to estimate the amount of fat expected to be collected. Details of the design and manipulation process are detailed here and shown in the videos.
Surgical procedure
Planning and Preparation
First, the premaxilla zone, here called as the first functional zone, is marked. The expected height of this zone is matched to the virtue curve between zygomatic arch and nasal tip. Then the transition zones around this functional zone, such as the nasolabial groove and cheek depression, are noted. As described in the Fat Harvesting section, the expected height of eyebrows, here called the second functional zone, is balanced with the nasal tip and the chin ( Fig. 1 ). The other zones are designated as transition zones, covering the areas from the functional zones to the hidden sites, such as hair-bearing areas. The borders between functional zones and transition zones are actually anatomic borders between fat compartments.
All the procedures are performed under general anesthesia. No tumescent techniques are used in fat harvesting, and no local anesthesia is administered to the recipient sites. The eyelids are closed with a 6-0 nylon suture before injection.
Fat Harvesting
The most common donor site is the lateral thigh, but occasionally the inner thigh or abdomen are also used. After the patient is prepared, a 50-mL syringe and sharp 3-mm cannula with multiple holes are used to harvest fat from the deep layer only. Normally, 80 to 100 mL of lipoaspirate is sufficient for pan-facial fat injection.
Fat Processing
The lipoaspirate is centrifuged at 2000 rpm for 3 minutes. The product has 3 layers. The uppermost layer and dark bottom layer are discarded. The central layer, a mixture of fat and blood plasma, is transferred into a 1-mL syringe for injection.
Fat Injection
A blunt, 1.5-mm cannula with a single side-hole is used for facial fat injection. Injection begins from the premaxillary area for contouring. For the first step, the cannula is placed through the mucosa of the gingival sulcus, normally with a finger press on the infraorbital rim for protection ( Fig. 2 ). This injection layer is very deep, close to the surface of the bone. The plunger is pushed very softly as the syringe is retracted, leaving a well-proportioned 0.2 to 0.3 mL fat graft per line in the tissue. Then the cannula is pushed into the tissue just beside the previous line. This injection maneuver is repeated during the next retraction again until a fan-shaped area is completed. Then, with a fresh syringe, another layer is laid above the previous one, also in a fan shape. In this way, 3- to 6-mL grafts are placed, according to the height needed ( [CR] ).
The next injection point is through the mucosa in the nostril. This layer is more superficial, located within the subcutaneous layer, crossing the previous layer. The transition to the infraorbital rim was performed through this point with very tiny fat droplet ( Fig. 3 , [CR] ).
Also through this point, 1- to 2-mL grafts are injected into the nasolabial groove, very deep, close to the surface of the bone surface, to soften the transition between the premaxillary area and upper lip ( [CR] ).
The next injection point is the tail of the eyebrow. A puncture is made in the skin with an 18G needle, then the fat injection cannula was placed through the subcutaneous layer. This sets the contour and height of the new eyebrow ( Fig. 4 ). The new eyebrow’s contouring balance with the new radix, while at the peak of the forehead in the profile. More grafts are left in the medial part of the eyebrow and fewer in the lateral part. This contouring can bring a flat face forward rather than outward. During the injection, the left finger is pressed against the superior orbital fissure to protect the vessels from injury ( [CR] ).