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Featured researches published by Ferit Demirkan.


Plastic and Reconstructive Surgery | 1999

Double free flaps in reconstruction of extensive composite mandibular defects in head and neck cancer.

Fu-Chan Wei; Ferit Demirkan; Hung-Chi Chen; I-how Chen

Extensive composite defects of the lower jaw are defined as those that involve skin, mandible, oral mucosa, and soft tissues. The enormous size and multilayered nature of these defects challenge most of the current reconstructive techniques. For reconstruction of extensive composite mandibular defects in 36 advanced oral cancer patients, two free flaps were used simultaneously in a complementary fashion. The aim was to provide bone reconstruction and adequate soft-tissue coverage in an optimal form. Primary reconstruction was carried out in 34 of 36 cases. The fibula osteoseptocutaneous-radial forearm fasciocutaneous flap combination was most commonly used (n = 20), followed by the fibula osteoseptocutaneous-rectus abdominis myocutaneous flap (n = 11). The other combinations included the fibula osteoseptocutaneous-tensor fasciae latae, the fibula osteoseptocutaneous-rectus femoris, the iliac crest-radial forearm, and the iliac crest-tensor fasciae latae flaps. In 11 cases, the second free flaps were attached to the distal runoff of the first free flaps because of unavailability of recipient vessels. The mean operation time was 12 hours 10 minutes. The complete flap survival rate was 93 percent (67 of 72 flaps) with 2.8 percent total (2 of 72) and 4.2 percent partial (3 of 72) flap failures. Median follow-up time was 14 months, and 44 percent of the patients were alive at the time of evaluation, surviving an average of 36 months. The average survival time for those who died was 11.1 months. The authors believe that in selected cases the double free-flap procedure for one-stage reconstruction of massive mandibular defects is justified because it is safe and effective and improves the quality of life and the number of days spent outside of the hospital for these patients.


Plastic and Reconstructive Surgery | 1999

Free fibula osteoseptocutaneous-pedicled pectoralis major myocutaneous flap combination in reconstruction of extensive composite mandibular defects.

Hung-Chi Chen; Ferit Demirkan; Fu-Chan Wei; Shao-loung Cheng; Ming-Huei Cheng; I-how Chen

Lateral composite mandibular defects resulting from excision of advanced oral carcinoma often require mandible, intra-oral lining, external face, and soft-tissue bulk reconstruction. Ignorance of importance soft-tissue deficit in those patients may cause significant morbidity and functional loss. Such defects, therefore, can be reconstructed best with a double free flap technique. However, this procedure may not be feasible for every patient or surgeon. An alternative procedure is a free fibula osteoseptocutaneous flap combined with a pedicled pectoralis major myocutaneous flap. This combination was used in reconstruction of extensive composite mandibular defects in 14 patients with T3/T4 oral squamous cell carcinoma. All patients were men, and the average age was 54.3 years. The septocutaneous paddle of the fibula flap was used for the mucosal lining of the defects while the bony part established the rigid mandibular continuity. The pectoralis major flap then covered the external skin defect in the face and cheek, and the dead spaces left by the extirpated masticator muscles, buccal fat, and parotid gland. One free fibula flap failed totally, and one pectoralis major flap developed marginal necrosis. At the time of final evaluation, nine patients (64.3 percent) were alive, surviving an average of 25.7 months. All patients eventually regained their oral continence and an acceptable cosmetic appearance. In conclusion, the fibula osteoseptocutaneous flap plus regional myocutaneous flap choice is a successful and technically less demanding alternative to the double free flap procedures in reconstruction of extensive lateral mandibular defects.


Plastic and Reconstructive Surgery | 1999

Microsurgical reconstruction in recurrent oral cancer: use of a second free flap in the same patient.

Ferit Demirkan; Fu-Chan Wei; Hung-Chi Chen; I-how Chen; Sheng-po Hau; Chun-ta Liau

Primary microsurgical reconstruction is the treatment of choice for ablative defects of oral carcinoma. As a result of this trend, more and more patients with recurrent oral carcinoma who have been initially treated with surgical excision and reconstructed with free flaps are being seen. However, a second microsurgical reconstruction attempt in these cases raises questions about the flap choices, availability of recipient vessels, and effects of previous treatment modalities. Herein, 35 patients with perioral carcinoma who had two successive tumor resections and reconstruction with free flaps on each occasion are presented. A total of 75 free tissue transfers were carried out for the first and second reconstructions. After the first tumor resection, 28 radial forearm fasciocutaneous flaps, 7 fibula osteoseptocutaneous flaps, 1 iliac osteomyocutaneous flap, and 2 rectus abdominis myocutaneous flaps were used. For reconstruction after the recurrence, 17 radial forearm fasciocutaneous flaps, 13 fibula osteoseptocutaneous flaps, 3 rectus abdominis myocutaneous flaps, 2 anterolateral thigh flaps, 1 jejunum flap, and 1 tensor fasciae latae flap were used. More vascularized bone transfers were performed during the second reconstruction since the excision for the recurrence frequently required segmental mandibulectomy. The complete flap survival rate was 97.3 percent and 94.6 percent with a reexploration rate of 7.9 percent and 13.5 percent for the first and second free tissue transfers, respectively. The mean follow-up time throughout the procedures was 37.5 months. Disease-free interval between reconstructions was 20.8 months. At the time of evaluation, 54.3 percent of the patients were surviving an average of 19 months since the second reconstruction. The results suggest that free flaps represent an important option in reconstruction of recurrent perioral carcinoma cases undergoing reexcision. When used in this indication they are as safe and effective as the initial procedure.


Annals of Plastic Surgery | 2005

Analysis of skin-graft loss due to infection: infection-related graft loss.

Sakir Unal; Gulden Ersoz; Ferit Demirkan; Emrah Arslan; Necmettin Tutuncu; Alper Sari

This prospective study was performed to analyze the causes of infection-related skin-graft loss in a general population of plastic and reconstructive surgery patients. One hundred thirty-two patients who received either full- or split-thickness skin grafts to reconstruct soft-tissue defects were included. The tissue defects were grouped according to the cause as follows: vascular ulcers (9.2%), burns (14.5%), traumatic tissue defects (36.6%), and flap donor-site defects (39.7%). In all cases, the preoperative evaluation indicated an adequate wound-bed preparation. However, graft loss secondary to infection was recorded in 31 patients (23.5%). The microbiological cultures revealed Pseudomonas aeruginosa in 58.1% of the cases (P < 0.05), followed by Staphylococcus aureus, Enterobacter, enterococci, and Acinetobacter; 58.3% of grafts in vascular ulcers, 47.4% of grafts in burns, 16.7% of grafts in traumatic-tissue defects; and 13.5% of grafts in donor-site defects were lost due to infection. Vascular ulcers and burns were more commonly associated with graft losses due to infection than other tissue defects (P < 0.001). No correlation was found between the etiological cause of the defects and the microorganisms cultured. However, Pseudomonas infections were more fulminant and caused an increased reoperation rate 4.2 times (P < 0.05). Full-thickness grafts were more resistant to infection than split-thickness grafts (P<0.05). Graft loss due to infection was also more common in grafts applied to the lower extremities or when performed at multiple sites. In conclusion, 23.7% of skin grafts were lost due to infection in a group of general plastic surgery patients. Infection-related graft loss was more commonly encountered in vascular ulcers and burn wounds, and the most common cause was Pseudomonas aeruginosa.


Plastic and Reconstructive Surgery | 1998

Reliability of the venae comitantes in venous drainage of the free radial forearm flaps

Ferit Demirkan; Fu-Chan Wei; Barbara S. Lutz; Tsan-Sheng Cher; I-Hau Chen

&NA; The radial venae comitantes are usually considered as an accessory venous outflow tract in the free radial forearm flap because of their smaller size and thinner structure when compared with those of the cephalic vein. To evaluate the reliability of the deep venous system, a single radial vena comitans anastomosis was performed to serve as the sole venous outflow tract in 94 consecutive radial forearm free flap transfers. The suprafascial dissection technique was used in flap elevation, which allowed preservation of the cephalic vein and the dorsal branch of the radial nerve. In all cases, the external diameter of at least one vena comitans was adequate (≤1.5 mm) to perform a smooth microvascular anastomosis; in none of the cases was a venous anastomosis failure detected. Preselected use of a single vena comitans for the venous drainage of radial forearm free flaps was proven to be reliable and was preferred because of the ease of flap dissection and better donor site appearance. (Plast. Reconstr. Surg. 102: 1544, 1998.)


Plastic and Reconstructive Surgery | 1996

Delayed effect of denervation on wound contraction in rat skin.

Canimdat Engin; Ferit Demirkan; Suhan Ayhan; Kenan Atabay; Namik K. Baran

&NA; Neuronal supply in soft tissues may be an important part of cutaneous wound healing. In order to observe the effect of denervation on wound contraction, rectangular full‐thickness skin defects were created on the dorsum of two groups of Wistar rats. In the experimental group (n = 20), spinal nerves corresponding to the area of the open wound (T11 to L2) were isolated and divided bilaterally. In the control group (n = 20), the same pairs of spinal nerves were dissected but left intact. Limits of denervation were verified by the pinprick test. Wound healing, which is primarily in the form of wound contraction in this model, was evaluated by tracing wound margins onto millimetric paper weekly. Wound contraction was delayed significantly in the experimental group (p < 0.05) at all follow‐up periods when compared with the controls. Loss of neuropeptide secretion from the nerve endings in denervated tissues may be responsible for the retarded wound contraction, since neuropeptides are thought to exert trophic effects on skin wound healing.


Burns | 2003

The effects of carnitine on distally-burned dorsal skin flap: an experimental study in rats

Emrah Arslan; Abtullah Milcan; Sakir Unal; Ferit Demirkan; Ayse Polat; Ozlen Bagdatoglu; Alper Aksoy; Gürbüz Polat

OBJECTIVE In ischemia and burn injuries, there are major alterations threatening tissue survival. Increased energy flow requirements are among the major problems in these disorders. Carnitine is an endogenous cofactor, which has a regulatory action on the energy flow from different oxidative sources. The purpose of this study was to determine the effects of carnitine in an experimental flap model. Biochemically, nitric oxide (NO), malondialdehyde (MDA), and acetylcholinesterase levels, and histopathologically tissue examination under light microscope were studied. METHODS In the rat dorsal skin, a 10 cm x 3 cm flap was marked. The most distal 3 cm x 3 cm of the flap was burned to full-thickness. The dorsal flap was elevated, and sutured back to its original site. Sixteen rats were divided into two groups (a control (1) and a study group (2)), consisting of eight rats in each. While the animals in the control group were just followed, the animals in the study group were administrated carnitine with a dose of 100 mg/kg per day for 7 days. RESULTS At the end of the experiment: the mean surviving areas of the flaps were 15.22 cm(2) (50.73%) in group 1, 20.53 cm(2) (68.43%) in group 2, and the difference was statistically significant (P=0.008). In the analysis of blood samples; the mean levels of NO were 22.63 and 40.78 micromol/l; of MDA were 6.74 and 3.79 ng/ml; and of acetylcholinesterase were 136.14 and 222.85 U/l in groups 1 and 2, respectively. The differences in the levels of NO (P=0.001), MDA (0.027) and acetylcholinesterase (P=0.006) were statistically significant. Histopathological examination revealed a full-thickness muscle necrosis in addition to skin tissue in the control group, while healing tissue was present with marked cellularity including mixed inflammatory cells and fibroblast proliferation with an increased vascularity in the form of capillary budding in the study group. CONCLUSION Carnitine has a positive effect in such a model, particularly in preventing the progressive effect of burn, and limiting the necrosis in the full-thickness burned part.


Plastic and Reconstructive Surgery | 1999

Management of secondary soft-tissue deficits following microsurgical head and neck reconstruction by means of another free flap

Fu-Chan Wei; Ferit Demirkan; Hung-Chi Chen; I-how Chen; Chun-ta Liao; Sheng-po Hau

Secondary soft-tissue deficits may develop following a microsurgical reconstruction in the head and neck region because of inadequate planning or chronic effects of radiotherapy. Although most cases could be managed with alternative methods, free flaps might be necessary in difficult cases. Herein are described 11 cases of microsurgical head and neck reconstruction in which secondary soft-tissue deficits required transfer of another soft-tissue free flap. All patients had malignant tumors treated with surgical resection, and their defects were reconstructed with free flaps. Seven patients received either preoperative or postoperative adjunctive radiotherapy. These patients gradually developed signs and symptoms of soft-tissue deficiency in the reconstructed area, and a soft-tissue free flap transfer was required for treatment within an average of 21.5 months of their initial reconstruction. Five rectus abdominis, one rectus femoris, one latissimus dorsi, one tensor fasciae latae myocutaneous, one radial forearm, one medial arm, and one dorsalis pedis flap were used for this purpose. All flaps survived completely. The average follow-up time was 32 months. Significant improvement was achieved in all cases, and no further major surgical procedures were required. Secondary soft-tissue deficits that could not be predicted or prevented during the initial microsurgical reconstruction may be treated successfully by a subsequent free soft-tissue transfer in selected cases.


Plastic and Reconstructive Surgery | 2003

Comparison of ischemic and chemical preconditioning in jejunal flaps in the rat.

Sakir Unal; Ferit Demirkan; Emrah Arslan; Ibrahim Cin; Leyla Cinel; Gulcin Eskandari; Ismail Cinel

Jejunum is one of the most frequently used free flaps in esophagus reconstruction. However, the sensitivity of intestinal tissue to ischemia decreases the margin of safety of this donor site while increasing the risk of postoperative complications such as fistula formation and stenosis. Ischemic preconditioning can increase the tolerance of jejunal tissue to ischemia. In this study, the authors investigated the effects of chemical preconditioning with adenosine infusion on ischemia reperfusion injury in the rat jejunum, and evaluated the presence of any additive effects of adenosine administration when used together with ischemic preconditioning. Forty Sprague-Dawley rats weighting 200 to 250 mg were used in the study. Rats were randomly divided into five groups. In group I (sham-operated controls), only laparotomy was performed. In group II (ischemia-reperfusion injury), the superior mesenteric artery was clamped for 40 minutes to induce ischemia in the small bowel, followed by 60 minutes of reperfusion. In group III (ischemic preconditioning), two cycles of 5-minute ischemia and 5-minute reperfusion were performed before implementation of the ischemia-reperfusion protocol used in group II. In group IV (chemical preconditioning), adenosine (1000 &mgr;g/kg) was infused into the internal jugular vein before the group II ischemia-reperfusion schedule was implemented. In group V (adenosine-enhanced ischemic preconditioning), adenosine (1000 &mgr;g/kg) was infused into the internal jugular vein before ischemic preconditioning, followed by 40 minutes of ischemia and 60 minutes of reperfusion. At the end of the reperfusion period, samples from the jejunum were harvested and myeloperoxidase activity was determined as a measure of leukocyte accumulation. Malondialdehyde levels were measured to assess lipid peroxidation. Histopathologic sections stained with hematoxylin-eosin were evaluated for the presence of mucosal damage according to the Chiu scoring method. Immunohistochemical staining by M30 monoclonal antibodies was performed to quantify the number of ischemia-induced apoptotic cells in the intestinal mucosa. The myeloperoxidase and malondialdehyde levels were significantly lower in groups I, III, IV, and V when compared with group II. Although there were no significant differences among myeloperoxidase and malondialdehyde levels in groups III, IV, and V, group I had significantly lower levels of activity compared with the other three groups. Histological scoring reflected significantly less damage in groups I, III, IV, and V compared with group II. Similarly, the number of apoptotic cells was significantly lower in groups I, III, IV, and V when compared with group II. However, no difference was detected among these four groups with regard to either histopathological scoring or apoptosis numbers. This is the first study showing that adenosine administration is as effective as ischemic preconditioning in inducing ischemic tolerance in the rat jejunum. However, there was no enhancement of ischemic preconditioning with prior adenosine infusion.


Aesthetic Plastic Surgery | 2003

Irradiated homologous costal cartilage: versatile grafting material for rhinoplasty.

Ferit Demirkan; Emrah Arslan; Sakir Unal; Alper Aksoy

For most surgeons, nasal septal cartilage is the first choice in septoplasty. However, when this source is depleted, an alloplastic implant material might be preferable over other autogenous donor sites in order to avoid additional scars, morbidity, and lengthened operating time. In the alloplastic spectrum, irradiated costal cartilage (ICC) has certain advantages. Herein, we present our results with ICC in a wide range of septorhinoplasties to show its versatility and reliability. Sixty-five patients were included in the study. There were 42 male and 23 female patients. According to the indications, there were four groups of patients: (I) secondary septorhinoplasty (n = 24), (II) traumatic deformity (n = 21), (III) primary septorhinoplasty (n = 13), (IV) deformity due to previous septal surgery (n = 7). The mean follow-up period was 33 months. No significant resorption was detected in any of the patients. Minor complications developed in four cases (6%), including deformity in the dorsal graft, excessive graft length, and erythematous nasal tips. Aesthetic and functional results were satisfactory in the remaining cases. The low incidence of major complications and the versatility of ICC make it a safe and reliable source of cartilage graft for both primary and secondary septorhinoplasties when autogenous septal cartilage is either insufficient or unsuitable.

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