Various injectable material has been used in facial soft tissue contouring, including autogenous material (free fat, dermis), heterogeneous material (bovine collagen), and alloplastic material (silicone, methyl-methacrylate spheres, polytetrafluoroethylene, and hyaluronic acid). The advantages of autogenous tissue grafts over alloplastic materials and heterogeneous transplants are well known. Volumetric reshaping of the face with autologous tissue injection is a popular and reliable method and good long-term results are achieved.
During the past five years, 313 secondary nasal deformities (286 female and 27 men) with slight skin irregularities or severe skin damage were treated by use of micro fat grafting. (Table-1) Follow up period is from one to five years.
Table.1 Patient Demographics
|Age Range||Patients, n313||Percentage of total||Sex|
Harvesting and Preparation of Fat Graft
Fat grafts were collected using a 10-mL syringe and a 3-mm cannula (which has been part of the author’s technique since 1996). In this study, with the patient under general anesthesia and through a small incision, fat grafts were harvested from donor sites without injection of local anesthetic into the donor sites. After the syringe was filled with harvested fat grafts, the cannula was removed from the 10-mL syringe and grafts were put into the body of a 10-mL Luer-Lock syringe after removal of the plunger and sealing of the aperture. Then, the sealed Luer-Lock syringes filled with the harvested fat grafts were centrifuged at 3000 rpm for 3 minutes. The upper liquid lipid layer and the lower aqueous layer were discarded and 1 g of first-generation cephalosporin was added for each 100 g of centrifuged fat tissue. The abdomen and flanks were the most common sites for fat tissue harvest. When these regions were insufficient for adequate harvesting, the trochanteric, buttocks, or medial thigh regions were used.
Freezing and Thawing Protocol
After the required amount of fat or tissue cocktail was injected, remaining fat or tissue cocktail was cryopreserved. Specimens were put into 10-, 20-, or 50-mL sterile tubes, labeled, frozen at –196°C in a liquid nitrogen tank, and transferred to a UF 601 medical refrigerator (Electrolux; Stockholm, Sweden) for storage at –80°C. To thaw, an estimated amount of cryopreserved graft specimens in sterile tubes were taken from the medical refrigerator 12 hours before use in the procedure, transferred to a regular refrigerator (–15°C), and, 1 hour before use, thawed slowly at room temperature.
Injection of Fat
The area of the nose to be injected was marked while the patient was standing. A local anesthetic mixture of 20 mL 0.5% bupivacaine, 0.50 mg adrenaline, 30 mL physiologic serum, and 20 mg triamcinolone acetonide was injected into recipient sites to decrease postoperative edema and ecchymosis and to create vasoconstriction of vessels to prevent or diminish the risk for micro embolism.
For injection, a 22- or 24-gauge intravenous cannula was used depending the thickness of skin (Fig. 1). To correct minor irregularities, 0.3 to 0.8 mL cryopreserved micro fat graft material was injected 1 to 3 times and, for major irregularities or defects, 1 to 6 mL was injected and repeated 3 to 6 times. For cases of cripple nose with damaged skin, injections of cryopreserved micro fat graft material were performed every 2 months 6 to16 times.
Repeat injections were performed using cryopreserved fat. Small amounts of fat were injected intradermally, subcutaneously, depending on the site of injection. For repeated injections a local anesthesia is used.
All patients were consecutive. Patients were evaluated by comparing preoperative and postoperative photographs. These photographs were taken in the same studio with the same equipment: a Nikon camera (Nikon Corp., Tokyo, Japan) with a 105-mm micro lens with two studio flash heads and the same film exposure, magnification, lighting, and angle. Recipient sites were marked preoperatively. During the first postoperative year, patients were seen every 3 months, and photographs were taken at every clinic visit. Annual follow-up and photography were taken thereafter. At each visit, patient and author assessment of the results were noted in the medical record. Clinical assessment was made using medical records of the treatment and by graded digital photographs. In addition, patient subjective satisfaction was written in the medical records. Patients were categorized into three groups according to severity of deformity: group 1: patients with slight irregularities on the skin of the nose, (when the irregularities are solved completely is rated good improvement); group 2: patients with marked irregularity and depressions on skin and cartilage ,( when the irregularity and depression is corrected sub totally is rated as “moderate improvement”, complete correction is rated good improvement”); group 3: patients with severe deformity with damaged skin. (When the damaged skin is ready to undergo reconstructive rhinoplasty is rated “good improvement”) The improvement is rated in overall clinical appearance using the following scale: 0 = no improvement, 1 = moderate improvement and 2 = good improvement.
In group 1 (280 patients), 1 to 3 injections of micro fat graft material provided satisfactory results in all patients In this group one patient experienced complication after over injection, which caused severe bruising that lasted three weeks with threat of necrosis. Complications resolved without squeal. In the second group, in which patients had multiple and severe irregularities (40 patients), 3 to 6 injections were necessary and resulted in patient satisfaction. In group 3 (11 patients), 6 to 16 injections were necessary to allow further nose reconstruction. (Table-1) Three patients in this group previously refused to undergo the forehead flap option, as recommended in previous consultation by other physicians. On these patients we started micro fat injection and, after several sessions of injections, the damaged skin recovered, allowing surgical intervention. Reconstruction was possible with immediate expansion of skin flaps and insertion of a cartilage graft. After elevation of the skin flaps, successful fat grafting was noted as proof of viability of the cryopreserved fat graft . Reconstruction of the nose was made with use of the patient’s own nasal skin and the result was pleasing, with good patient satisfaction. After treatment of damaged skin by cryopreserved micro fat grafting, no complications—such as vascular impairment, skin necrosis, or infection—occurred.
Facial rejuvenation with autologous fat transfer is a performed procedure in aesthetic plastic surgery. The use of micro fat grafting for the nose is beneficial. However, few articles have been published specifically about micro fat grafting for the nose; rather it is mentioned in passing in general facial micro fat grafting literature. To correct skin irregularities or depressions in the nose, many injectable were used previously because they were readily available and preferred by many physicians. In the hands of inexperienced physicians, injection of these materials in the nose can cause many complications. Nowadays, hyaluronic acid injections are preferred because they are readily available and result in relatively fewer complications than other fillers. However, the advantage of hyaluronic acid over permanent fillers is not free of complications. The author and others. stress the benefit of the use of micro fat grafting for correction of small or severe irregularities of the skin of the nose. This easy procedure does not necessitate grafting of the cartilage and should always be preferred to use of alloplastic material.
The result obtained after treatment by use of micro fat injection to damaged skin of the nose is similar to the result obtained with burn scarring or radio dermatitis.
The disadvantage of the necessity of repeated injections may be lessened by cryopreservation of fat grafts for further use. The preservation of fat grafts for future application has been of interest to aesthetic plastic surgeons. With cryopreservation of harvested fat grafts for future reinjection, repeated fat graft harvesting is unnecessary. Previous experimental studies in preservation of harvested fat at –16 °C and –18 °C for 1 to 2 weeks showed variable results; injected fat survived in study and control groups and a decrease was seen in viable adipocytes and fat cell necrosis in an animal model that received preserved fat. Dry freezing in liquid nitrogen at –35°C and –195°C revealed the ability to maintain the viability and histology of preserved fat grafts. Many studies have found that adding cryoprotective agents (dimethyl sulfoxide, trehalose, or glycerol) achieves adequate protection of fat grafts during cryopreservation with different protocols of freezing and thawing.
Acceptance of results by patients was uniformly positive when this method of cryopreservation was used.
Indications may be summarized as follows:
1—Slight skin irregularities where cartilage graft treatment is not suitable
2—Moderate skin irregularities on which fat grafting is less invasive than cartilage graft
4—Patients who does not accept another revision rhinoplasty.
5—Less cost for patients who had rhinoplasty elsewhere
6- Only restriction is nasal skin infection and herpes.
Micro fat grafting is autologous tissue transfer. No late complications are seen with this material and it is ideal for correction of minor irregularities. In patients who cannot undergo revision rhinoplasty it is a perfect option. If used as cryopreserved tissue for several sessions, it is well accepted by patients. It is also a wonderful salvage procedure for severely damaged skin of the nose. Not a replacement for modern rhinoplasty techniques, may be compliment to well-known techniques.