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BACKGROUND: Phosphatidylcholine formulation has been used to dissolve local fat deposits. This study aimed to evaluate and compare the effects of phosphatidylcholine formulation and its vehicle sodium deoxycholate alone on different cell lines to understand better its mechanism of action. METHODS: Cells and media including 3T3-L1 preadipocytes, normal foreskin fibroblasts, neonatal human dermal microvascular endothelial cells (CADMEC), and fetal human skeletal muscle cells (HSkMC) were used. After 24 h, cells were exposed in 3-4, 5-dimethylthiazol-2-yl-2, 3-diphenyl tetrazolium bromide reagent (MTT assays) to increasing dosages of phosphatidylcholine formulation (0.0156-0.5 mg/ml) or an equivalent vehicle, sodium deoxycholate solution, pH 9.0 (0.0066-0.210 mg/ml). Viability was assessed after 1, 2, and 3 days of treatment. Fat tissue (4 x 4 cm) obtained ex vivo from the dorsal fat pads of five rabbits was injected with 2 ml of phosphatidylcholine formulation (50 mg/ml), sodium deoxycholate (21 mg/ml), or normal saline and incubated for 24 h. These were examined histologically to identify cell lysis and morphologic changes. RESULTS: At 0.125- and 0.25-mg/ml doses of phosphatidylcholine solution, CADMEC and HSkMC were more sensitive (P < 0.001, one-way ANOVA) than adipocytes at all time points examined. Phosphatidylcholine formulation at a dose of 0.5 mg/ml and the equivalent vehicle, sodium deoxycholate, at a dose of 0.21-mg/ml both induced nearly 100% fat cell lysis after 24 h, and evidence of cell lysis as early as 6 h after exposure. After incubation of fat tissue for 24 h with phosphatidylcholine formulation, loss of intracellular lipid staining with an increase in extracellular lipids was seen. CONCLUSIONS: Isolated sodium deoxycholate was almost as effective as the phosphatidylcholine formulation, at clinical concentrations, in reducing the viability of mature adipocytes over time. Similar cytotoxic effects of phosphatidylcholine formulation on normal foreskin fibroblasts, endothelial cells, and human skeletal muscle cells also were observed. The data prove that the formulation acts in a nonspecific manner and that its unintentional administration to other tissues causes cell death.

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Malfunction of the marginal mandibular nerve, either in combination with a generalized facial palsy or in isolation, can cause an unpleasant and disturbing appearance around the mouth. In total palsy, a cross-facial nerve graft combined with a free vascularized muscle transplant will usually deal with this problem successfully; however, all older procedures used in this situation are unpredictable. For the isolated palsy, procedures such as digastric muscle transfer or sling suspension are not uniformly successful. A method using the contralateral, nonaffected lower lip orbicularis muscle is described. A wedge is removed from the paralyzed lower lip and the orbicularis is advanced to the modiolus to provide a functional orbicularis all the way across the lower lip up to the angle of the mouth. This is a simple outpatient procedure that has produced satisfactory results in most cases.

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The problem with neurofibromatosis is that it has always been classified from a pathological point of view. This really does not help when it comes to clinical management. This article presents a classification that relates to the severity of the condition and to its clinical management. In the head and neck area, the important region from the point of view of treatment, is the orbit and its contents. It is possible to classify the neurofibromatosis of the facial area in three grades, and these signify the severity of orbital involvement. This directly relates to the surgical management of these patients. Once this system is adopted, surgical decision-making is relatively easy, although the execution of the management is complex.

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A method of harvesting fat with intact cells using a veterinary needle and a fine needle aspiration device is described. Viable fat cells are obtained in large amounts. A large subcutaneous postradiation thigh defect was reconstructed with harvested fat placed subcutaneously in various sessions. A good, but not perfect, reconstruction was obtained. This case indicates that viable fat cells can be transplanted and can survive even in the adverse environment of a postradiation defect.

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Distraction osteogenesis has become a popular treatment of congenital maxillocraniofacial anomalies. Many ingenious internal and external devices have been developed and used. The rigid external distraction system based on systems previously used in correction of maxillary retrusion offers postoperative adjustment in two dimensions. Figueroa and Polley reported the use of this device with minimal morbidity in children as young as 5 years of age. They reported no problems with infection, bleeding, pain, loosening of the intraoral splint, dental injury, or wear problems in a series of 14 consecutive cleft patients. Recent modification of the system, rigid external distraction II, has allowed it to be applied to more complex craniofacial deformities that require a LeFort III osteotomy. A review of the neurosurgery and orthopedic literature revealed that halo complications relate primarily to the skull pins. In most cases, these complications can be prevented if the device is carefully applied and monitored. Early recognition and prompt treatment of complications are important. After experience with this system for advancement at the LeFort III level, six patients with various syndromes involving the craniofacial skeleton have undergone LeFort III level distraction osteogenesis with the rigid external distraction device in combination with a planned and stabilized frontosupraorbital advancement. In one of these cases, a 7-year-old child fell on the device after discharge from the hospital and sustained a compound depressed skull fracture that required debridement and repair.

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Uniform patient photographs that create permanent records are essential for any visually oriented medical specialty. These images are valuable for any plastic surgeon's practice for various reasons; thus, standards and recommendations for clinical photography should be well-known. There are several articles published on this issue, but it is still not uncommon to be exposed to medical publications and presentations that fail to satisfy clinical photography standards. This stimulated an interest in reviewing the important factors that are essential to achieve consistent, comparable clinical photographs with 35-mm single-lens reflex photography.

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After nasal surgery, thinning of the nasal skin, bony irregularities, or adhesions of dorsal skin to underlying bone can all occur. These problems can be solved by using either alloplastic materials or various autogenous tissues. In this study, AlloDerm, a dermal replacement derived from cadaveric skin, has been used to cover the osseocartilaginous framework of the nose in an attempt to achieve a smooth contour and a natural feel in secondary rhinoplasties. Fifteen patients were treated and observed for a minimum of 24 months. Clinically palpable or visible bony irregularities were successfully covered, and adhesions of dorsal skin to nasal bones were diminished. Prolonged but not socially unacceptable dorsal nasal swelling, which resolved during the first 4 months, seemed to be the only problem related to its use. With this limited experience, AlloDerm was found to be useful in secondary nasal surgery to cover osseocartilaginous irregularities, to eliminate the adhesions between nasal bones and overlying skin, and to create a smooth nasal dorsum.

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Skin grafts regain their sensory innervation from the graft bed by the regeneration of nerve endings. Although some clinical studies report sensory recovery in skin grafts implanted on free muscle flaps, the mechanism of recovery is obscure. The purpose of this study was to investigate nerve regeneration in experimental skin grafts on free muscle flaps to elucidate this phenomenon. Thirty-eight male Sprague-Dawley rats, weighing 450-550 g were used in the study. The rat gracilis muscle flap was the free flap model transferred from one groin to the other using microvascular anastomoses. Full-thickness skin grafts harvested from the abdomen were used to cover the free muscle flaps after transfer. Four study groups were formed: Group I (n = 10): Free muscle flaps were transferred without any nerve anastomosis; Group II (n = 10): Free flaps transferred with the anastomosis of the muscle's motor nerve to a sensory nerve at the recipient site; Group III (n = 10): Free flaps transferred with the anastomosis of the muscle's motor nerve to a motor nerve at the recipient site; Group IV (n = 8): Skin grafts were placed directly on the fascia layer over the medial hindlimb muscles and served as controls. The specimens were harvested for histologic examination after 12 weeks. Histologic examination was performed to visualise regenerating nerve endings using H&E, S100, Luxol Fast Blue and tyrosine hydroxylase staining. The specimens were categorically scored according to the staining pattern of neural structures around pilosebaceous units and statistical comparisons were performed by using paired t-test. Skin grafts in both Group II and Group III markedly received tyrosine hydroxylase at the base of their pilosebaceous units in many of the specimens and functional nerve twigs could also be traced from the muscle layer to the overlying skin graft. In contrast, the skin grafts in Group I did not show any nerve function in the central parts. The overall staining scores of Groups II, III and IV were significantly higher than Group I (P < 0.05; P < 0.001; P < 0.05, respectively). There was no statistically significant difference between other groups. No myelinated nerve fibres could be detected in any of the skin grafts with Luxol Fast Blue technique. It was concluded in the present study that skin grafts over reinnervated free muscle flaps can develop significantly better innervation than skin grafts over non-innervated muscle flaps. However, the activity in skin appendages indicating nerve regeneration may only imply a gross sensation and in the absence of any myelinated nerve fibres transmission of finer sensation cannot be expected in any of the study groups.

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A modified facelifting technique with simultaneous carbon dioxide laser resurfacing makes for improved quality of the overlying skin, which enhances the effect of repositioning of the deep facial structures. Concerns have been expressed with regard to complications which may occur when this approach to facelifting is used. This paper presents guidelines which, if observed, allow this procedure to be performed safely in terms of laser skin injury. Over 100 patients have been treated using this combined technique, frequently with the addition of further ancillary procedures. Patient follow-up ranged from 1 to 36 months and showed none of the feared complications to have occurred. This combined approach has improved the results achieved previously by either technique used on its own. In addition, it saves time for both patient and surgeon, and apart from redness, the postoperative recovery period is similar. This technique requires patient education and a postoperative team effort by surgeon, nurse, and aesthetician. Experience has shown that this is a safe procedure which can produce good results with the proper pre- and postoperative management.

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Reconstruction of oroantral defects, which are usually caused by tumor resection, is challenging. These defects become an even more difficult problem when they comprise multiple layers including oral mucosa, subcutaneous tissue, muscle and skin. This paper describes such a case in which a three-layer closure using a palatal flap, a buccal fat pad flap and a local skin flap was successfully performed.

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Hydroxyapatite cement is a calcium phosphate preparation composed of tetracalcium phosphate and dicalcium phosphate anhydrous powders. When mixed with water it isothermically forms a paste which can easily be shaped intraoperatively. This mixture sets in approximately 15-20 min and converts into water insoluble, nonceramic, microporous hydroxyapatite in 4 h. This biomaterial was used to correct either congenital or traumatic craniofacial contour irregularities or deficiencies in 20 patients. On follow-up there was only one patient who required repeat surgery for further correction, there were no other complications. The good cosmetic results, the ease of operation, the pliability of the cement paste allowing precise moulding during application, the short operation time and the avoidance of a donor site makes hydroxyapatite cement an attractive material for treating craniofacial contour defects. Careful long term follow-up is necessary to establish its safety and reliability.

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The purpose of this study was a retrospective evaluation of the treatment of congenital pigmented nevi using the phenol chemical peel technique. Patients were treated with standard Baker formula in the operating room under general anesthesia or intravenous sedation with continuous electrocardiogram monitoring. A total of 20 patients were reviewed (13 girls and 7 boys, mean age 3.8 years). Eight patients had nevi located on the face, five patients had trunk lesions, and three patients had lesions on the thighs. Two patients had nevi located on both the face and the trunk, and two patients had involvement of the face, trunk, and thigh. Three of the above patients had the classic "bathing trunk" distribution of the nevi. A test area was peeled in four patients, and in five patients preoperative biopsies were performed to rule out malignancy before initiation of therapy. An average of 2.6 treatments were performed per patient. Two patients had adjunctive dermabrasion to increase the depth of peel and to contour surface irregularities. The length of follow-up ranged from 6 to 84 months with a mean of 28 months. Healing of the wounds occurred within 2 to 3 weeks postoperatively. Seventy-five percent of patients had satisfactory cosmetic improvement in the appearance of the lesions following treatment. Four patients had recurrence of the pigmentation after an initial lightening response, three of whom had their nevi subsequently excised. There was no incidence of hypertrophic scarring or cardiac and/or renal complications. There was one death from complications of leptomeningeal melanocytosis. Chemical peeling of congenital pigmented nevi is an acceptable alternative method of therapy for those lesions that are too large for excision and primary closure or for lesions in which excision would result in unacceptable scars in areas such as the face.

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Cranioplasty is the most common method for correcting cranial defects. A number of innovations have been made to optimize bone repair. Before their use in humans, extensive animal trials must be performed to establish efficacy. However, the literature provides only scant and inconsistent data regarding animal controls. The purpose of this study, therefore, was to determine the critical size cranial defect in the rabbit model. Cranial defects ranging from 0.5 to 1.5 cm were created in 18 New Zealand White rabbits. The rabbits were then killed at 9 and 18 weeks and the defects examined using CT imaging and histologic analysis to determine bone healing. It was determined that cranial defects greater than 1.5 cm failed to heal spontaneously. Thus, the critical size cranial defect in the rabbit model is 1.5 cm.

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PURPOSE: The pathogenesis, natural history, histopathology, and recommended treatment for orbital angiosarcoma are illustrated and reviewed. METHODS: Case report. RESULTS: A 71-year-old white male presented with bluish discoloration and swelling of the left medial canthal area. A fine needle aspiration and excisional biopsy with histopathologic examination was performed, which showed angiosarcoma. Pattern of growth was demonstrated radiographically and histopathologically, confirming primary orbital angiosarcoma. Subsequent wide surgical resection was carried out, with substantial reconstruction of the left orbital and periorbital area. The patient responded well to the surgery, and was free of tumor after six years of follow-up. CONCLUSION: Angiosarcoma is a rare and highly malignant tumor of epithelial origin. The aggressive nature of this tumor usually results in a high mortality rate despite treatment. However, early diagnosis and wide surgical excision has resulted in successful treatment of these tumors.

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