Mucosal malignant melanoma in upper aerodigestive tract: report of two cases.

Primary malignant melanoma has been seen in virtually all sites and organ systems where neural crest cells migrate. Upper aero-digestive tract is the unusual site. We presented two cases of mucosal malignant melanoma. A 59-year-old female patient had been suffering from nasal airway obstruction and headache for three months, and was admitted to our clinic. There was an upper cervical lymphadenopathy 5 cm in diameter ipsilaterally. Computerized tomography presented a nasal mass originating from the left maxillary sinus, and extending into nasal cavity and the left lateral wall of nasopharynx. Left total maxillectomy and radical neck dissection was performed. Postoperative radiotherapy was applied. A 68-year-old male patient suffering from nasal airway obstruction, hypernasality, dysphagia, and oral bleeding was admitted to our clinic. Oral examination revealed the tumoral mass protruding downward through oropharynx. The second patient referred to medical oncology. There was no recurrence in the first patient 18 months later. And the second patient died one year later. We believe that nasal mucosal malignant melanoma was rare, and carefully evaluated since it may be amelanotic lesion. Nasopharyngeal mucosal malignant melanoma is very rare, and has worse prognosis.

Bilateral basal cell carcinoma symmetrically appearing on lower eyelids: a case report.

Basal cell carcinoma is the most common skin malignancy and is found in skin exposed to the sun. It is rarely seen bilaterally in ears, ankles or breasts. There has been no literature about bilateral basal cell carcinoma of lower eyelids symmetrically. A 68-year-old male patient had been suffering from two lesions on his lower eyelids for two years. The first lesion appeared on the right lower eyelid two years ago and got larger. Then the second lesion occurred on the left lower eyelid a year and a half ago. The patient had worked as a farmer for fifteen years. Physical examination revealed ulcerated lesions, with surrounding hyperemia, 12 x 6 mm in size, on both lower eyelids. Both lesions were excised and repaired with lateral malar flap+mucosal graft. One year later, there no evidence of recurrence, and postoperative scars were functionally and cosmetically acceptable. We present a case of bilateral basal cell carcinoma involving both lower eyelids symmetrically, reviewing the literature.

Pyogenic granuloma appearing on port-wine stain: a case report.

BACKGROUND: Pyogenic granuloma has been reported to be associated with hemangiomas and hamartomas, including port-wine stain. It has been suggested that the spontaneous development of pyogenic granuloma in port-wine stain might be associated with microscopic arteriovenous anastomoses in highly vascularized areas such as the fingers, hands, lips, tongue and face. CASE REPORT: A 25-year-old male patient presented with a history of a reddish, solitary nodule on the posterior cervical area for eight months. There had been an associated port-wine stain at the same localization since birth. Physical examination revealed a solitary, strawberry-like dome-shaped papule, 12 mm in diameter, within a well-demarcated reddish colored surrounding patch which had been present on the posterior cervical area. The lesion was excised, considering pyogenic granuloma arising in a port-wine stain. Histopathologic examination showed a mass of capillaries with variable luminal diameters, infiltration of inflammatory cells, and immature endothelial proliferation in the upper dermis. The capillaries were organized into lobules separated by fibrous stroma and were surrounded by an epithelial collarette. Immunohistochemical staining for factor VIII-related antigen supported all these findings of the port-wine stain. CONCLUSION: We present a pyogenic granuloma arising in port-wine stain on the posterior cervical area, since the posterior cervical area is not as highly vascular as the fingers, hands, lips, tongue and face. We believed that the collar of the patient's shirt continuously traumatized port-wine stain, and consequently led to the development of pyogenic granuloma.

Prefabrication of periosteal graft alone or with oxidised cellulose: an experimental study.

The purpose of this study was to evaluate the feasibility of prefabrication of periosteal grafts, alone or with oxidised cellulose (surgicel), which was an osteoinductive material using femoral vasculature. Fifteen white New Zealand rabbits were used in both femoral regions (30 grafts), and randomly divided into three groups including five rabbits (10 grafts): the control group, the periosteal graft group, and the periosteal graft+surgicel group. A periosteal graft, 30 x 40 mm in size, was obtained from the calvarium of each rabbit. The periosteal graft taken was divided into two equal parts, 20 x 30 mm. All these periosteal grafts were sutured in the shape of tube. In all rabbits, femoral vasculature and periosteal tube was Included in a silicone tube. Additionally, in the control group, femoral vasculature was cut above and below the silicone tube, whereas in the periosteal graft+surgicel group, surgicel was added to the periosteal graft. The results were evaluated macroscopically and histopathologically in the second (two rabbits for each group - 4 grafts) and fourth week (3 rabbits for each group - 6 grafts). In the second week, In all three groups, while no osteoid tissue that indicated osteogenesis developed, it was seen that inflammation and increased vascularity occurred. Surgicel was observed to be absorbed in the periosteal graft+surgicel group. In the fourth week, fibrotic tissue was developed whereas inflammatory tissue disappeared; any osteoid tissue or lamellar bone was not accompanied in all three groups. In conclusion, we do not believe that periosteum was able to survive as a graft, and we found that neovascularization occurred too slowly to preserve the bone forming qualities of the periosteum. We suggested that it could not be prefabricated, being taken away from its donor site although surgicel was used as a stimulating material.

Effects of polyglycolic acid bioabsorbable membrane and oxidised cellulose on the osteogenesis in bone defects: an experimental study.

BACKGROUND: The purpose of the present study was to determine the effects of polyglycolic acid bioabsorbable membrane and oxidised cellulose on the osteogenesis in bone defects. MATERIALS AND METHODS: Fifty-four male adult New Zealand White rabbits weighing 3.0 to 3.5 kg were used. The rabbits were randomly divided into three groups of eighteen rabbits: the control group (n = 18), the polyglycolic acid bioabsorbable membrane group (biofix group, n = 18), and the oxidised cellulose group (Surgicel group, n = 18). Each experimental group was also randomly subdivided into two subgroups of nine rabbits, one with periosteum and the other without periosteum. A rectangular transosseous calvarial bone defect, 16 x 20 mm in size, was created. In the control group, the calvarial bone defect was not filled. Polyglycolic acid bioabsorbable membrane (Biofix, Bioscience, Tampere Finland) was implanted over the bone defect area in the biofix group, and oxidised cellulose (Surgicel, Ethicone, London, United Kingdom) in the Surgicel group. The calvarial bone defects were evaluated-histopathologically in the second, sixth, and tenth weeks. RESULTS: As for the results of sequential bone regeneration, macroscopical and histological aspects were observed. Bone formation was significantly enhanced by oxidised cellulose in the calvarial bone defects covered with periosteum, whereas cartilage formation was observed in bare calvarial bone defects. CONCLUSION: We believe that oxidised cellulose has osteogenic potential, and that polyglycolic acid bioabsorbable membrane inhibits osteoinductive effect and retards osteogenesis.

The fate of neurotization techniques on reinnervation after denervation of the gastrocnemius muscle: an experimental study.

In nerve injuries, if it is not possible to reinnervate muscle by using neurorrhaphy and nerve grafting technique, reinnervation should be provided by the use of neuroization-directly implanting motor nerve into muscle. A comparative study of three techniques of neurotization is presented in rabbits. In this experimental study, a total of 40 white New Zealand rabbits were used and divided into four groups, each including 10 rabbits. In the first group (control--Group 1), only surgical exposure of the gastrocnemius muscle, main muscle nerve (tibial nerve), and peroneal nerve was done, without any injury to the nerves. In the second group (direct neurotization group--Group 2), the tibial nerve was transected, and the peroneal nerve, which had already been divided into fascicles, was implanted into the lateral head of the gastrocnemius muscle aneural zone. In the third group (dual neurotization group--Group 3), the tibial nerve which had been transected and re-anastomosed, and the peroneal nerve were implanted into the lateral head of the gastrocnemius muscle. In the last experimental group (hyperneurotization group--Group 4), fascicles of the peroneal nerve were implanted into the lateral head of the gastrocnemius, preserving the tibial nerve. Six months later, changes in the histologic pattern and the functional recovery of the gastrocnemius muscle were investigated. It was found that functional recovery was achieved in all neurotization groups. Groups with the tibial nerve transected had less muscular weights than those of groups with the tibial nerve intact. EMG recordings showed that polyphasic and late potentials were frequently seen in groups with the tibial nerve transected. Degeneration and regeneration of myofibrils was observed in such groups as well. New motor end-plates, including vesicles, were formed in a scattered manner in all neurotization groups. As a result, the authors conclude that direct and dual neurotization techniques are useful in peripheral nerve injuries, if it is not possible to reinnervate muscle by using neurorraphy and nerve grafting, and that there is no suggested superiority among these techniques.

Effects of some pharmacological agents on the survival of unipedicled venous flaps: an experimental study.

Clinical and experimental studies have been conducted to improve the survival of venous flaps. As a result of these studies, although various survival mechanisms were raised, none obtained satisfactory information. Venous stasis, and the resultant venous thrombosis, is a factor that decreases the survival of venous flaps. In this study, we evaluated the effects of two antiinflammatory agents, etodolac and etofenamate, on the survival of unipedicled venous flaps. In this study, 35 male New Zealand white rabbits (3,500-4,000 g) (70 ears) were used. Perichondrocutaneous flaps, 3 x 4.5 cm in size, were designed and raised, keeping the central veins intact in the middle of venous flap. Central arteries and nerves were ligated and transected both proximally and distally, to prepare unipedicled venous flaps. A silicone sheet was placed between the cartilage tissue and flap, to prevent blood flow and revascularization beneath. The subjects were divided into seven groups, consisting of five rabbits (10 ears). In the negative control group (group I), the single vascular pedicle of venous flaps, central veins were ligated and flaps sutured into their own place as the composite graft. In the positive control group (group II), after venous flaps were prepared, normal saline, 0.2 mL, was given subcutaneously. In the first of five experimental groups (group III), unfractionated heparin (100 U/day) was given subcutaneously. In the second experimental group (group IV), etodolac (5 mg/kg/day) was given subcutaneously. In the third experimental group (group V), etophenamate (5 mg/kg/day) was given orally through a feeding tube. In the fourth experimental group (group VI), parnaparin (5 anti-Xa U/kg/day) was given subcutaneously. In the fifth experimental group (group VII), nadroparin (5 anti-Xa U/kg/day) was given subcutaneously, about 7 days postoperatively. At the eighth postoperative day, surviving areas of venous flaps were measured, and the results were evaluated by Kruskal-Wallis ANOVA and Mann-Whitney U-test (P < 0.05). Biopsies were also taken from the flaps for histological evaluation of border of necrotic tissue. Surviving areas of unipedicled venous flaps were larger in experimental groups than those in negative and positive control group (P < 0.05). However, comparison of the experimental groups demonstrated no statistically significant difference (P > 0.05). We concluded that all pharmacological agents used in the experimental groups succeeded in increasing the survival of unipedicled venous flaps. Survival of the unipedicled venous flap was higher in venous flaps than that of composite graft, clearly showing the importance of the venous pedicle.

Exposure of high-density porous polyethylene (Medpor) used for contour restoration and treatment.

Porous high-density polyethylene (Medpor) is a biocompatible large-pore, high-density polyethylene implant. It is well tolerated by surrounding tissue, and its porous structure is rapidly infiltrated by host tissue. It is a highly stable and somewhat flexible porous alloplast that has rapid tissue ingrowth into its pores. However, when the implant is placed under a thin cover of skin, there is a risk of exposure. A total of 52 Medpor implants were placed in 31 patients over a four-year period. The implants were used for the chin, malar area, nasal reconstruction, ear reconstruction, orbital reconstruction, and the correction of mandibular contour deformities. Many of these implants were placed in areas considered problematic, such as those with thin or atrophic soft-tissue coverage and extensive scarring. There were nine complications, including three patients in whom the implant was exposed; these are presented here.

Ischaemia-reperfusion injury of the peripheral nerve: An experimental study.

Although the neuropathology of ischaemic fibre degeneration is relatively well known, its pathogenesis is poorly understood. One of the presumed mechanisms is oxidative stress, causing the breakdown of the blood-nerve barrier (BNB) and ending in lipid peroxidation. We evaluated the effect of ischaemia and reperfusion on the sciatic-tibial nerve of the rat and investigated the biochemical, pathological, and functional evidence of BNB disruption and lipid peroxidation. The distal portion and trifurcation of the sciatic nerve were rendered ischaemic by clamping the femoral vessels for 3 h and followed by varying durations of reperfusion. Reperfusion resulted in an increase in lipid peroxidation beginning from the first hour and increasing until the seventh day, followed by a gradual decline over the following weeks. Nerve oedema and ischaemic fibre degeneration (IFD) consistently became more severe and prominent with reperfusion, indicating that oxidative stress damages the BNB and causes IFD. Results of functional testing by the sciatic function index correlated with other parameters as walking track analysis results got worse as reperfusion periods increased. Impairment of walking patterns was more striking after the first day and continued up to the third week. These data indicate that severe ischaemia of the peripheral nerve results in reperfusion injury, functional impairment, and disruption of the BNB. Microvascular events, which may occur during reperfusion, may be important in amplifying the nerve fibre degeneration that initiated during ischaemia.