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Sakir Unal

Publications and source records attributed to Sakir Unal.

31 records · Page 2Linked to original sources
PubMed2003

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

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 microg/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 microg/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.

Adenosine↗
PubMed2003

Irradiated homologous costal cartilage: versatile grafting material for rhinoplasty.

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.

Adult↗
PubMed2003

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

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.

Acetylcholinesterase↗
PubMed2003

Versatile anterolateral thigh perforator flap: case of tailored reconstruction for a large temporal and parotidectomy defect.

Perforator flaps have introduced an advance in microsurgical reconstruction, by allowing the design of flaps that are tailored for a specific defect. In this report, the reconstructive technique in a case of temporal squamous-cell carcinoma is presented as an example of this trend. Following wide resection of the skin tumor, superficial parotidectomy was performed as a part of the lymph-node dissection. An anterolateral thigh perforator flap was harvested, including a segment of the vastus lateralis muscle in connection with the skin perforators, to reconstruct both the skin defect and the parotidectomy-related soft-tissue deficit. The muscle segment was reinnervated by the greater auricular nerve to diminish atrophy. The aesthetic result was satisfactory. Minor's starch-iodine test demonstrated prevention of Frey's syndrome. The anterolateral thigh flap is a versatile donor that allows individual variations in design for custom-made flaps.

Carcinoma, Squamous Cell↗
PubMed2003

Poland's syndrome with rare deformities: reconstruction with latissimus dorsi muscle through a single short incision.

We describe a 22-year-old man with Poland's syndrome and two other rare deformities which, to our knowledge have not been reported previously. The first deformity was a fibrotic band between the nipple-areola complex and the medial epicondyle of the humerus, and the second was a fifth digit with two phalanges. A single midaxillary vertical incision was used to harvest and then transfer the latissimus muscle for soft tissue reconstruction of the chest wall deformity. Almost complete symmetry was achieved and the scar was well hidden by the arm. The aesthetic and functional results were satisfactory.

Adult↗
PubMedDate not supplied

Unilateral brachial plexus injury occurring after reduction mammaplasty.

A left neuropraxic brachial plexus injury was seen after reduction mammaplasty. The clinical signs of plexopathy were noted in the very early postoperative period. The partial axonal damage was heavy in the upper and posterior branches and moderate in the medial branch of the plexus. The hyperabduction of the upper extremity during the surgery was thought to be the main cause. With a close followup and extensive physiotherapy, in addition to B complex vitamins, a full recovery was achieved at the end of the tenth week.

Adult↗
PubMedDate not supplied

Augmentation rhinoplasty with a combination of triple cartilage grafts for secondary rhinoplasty in a middle-aged population.

Because of physiologic changes with advancing age as well as previously traumatized and then healed tissues, secondary rhinoplasty for a middle-aged patient is a challenging procedure. Depending on both factors, changes in the midvault can cause a functional airway disorder, and the nose also may need a complete correction for cosmetic purposes. To achieve aesthetic and functional outcomes, augmentation rhinoplasty using a combination of triple cartilage grafts, namely, spreader, columellar, and dorsal onlays, was performed for 12 patients. Sufficient nasal airways with satisfactory appearance were achieved for 11 of 12 patients. Only one patient had improved but still insufficient nasal function with a good aesthetic result. Augmentation rhinoplasty using a combination of triple cartilage grafts for middle-aged patients could be considered an effective procedure for improving the patient's nasal airway and appearance.

Age Factors↗
PubMedDate not supplied

[The need for successive free flap applications for soft-tissue reconstruction in a case with recurrent oral carcinoma].

A case of difficult oncologic oral reconstruction is illustrated, in which soft tissue deficits resulting from failure of conventional techniques were treated by successive free tissue transfers. A thirty-eight-year-old man presented with squamous cell carcinoma in the right retrotrigonal region. The tumor was resected and the defect was reconstructed with the use of a tongue flap and skin graft. However, trismus occurred following radiotherapy, which was released by the help of a radial forearm free flap. The patient developed local recurrence several months later and right hemimandibulectomy, total maxillectomy, and hemiglossectomy were performed. The resulting en bloc defect was reconstructed by a free fibula osteocutaneous flap combined with a pedicled extended pectoralis major myocutaneous flap. The pectoralis flap was complicated by partial necrosis resulting in a large orocutaneous fistula and oral commissure incompetence. As the source of either a local or regional flap was inadequate, an anterolateral thigh myocutaneous free flap was used to fill the maxillary defect. No complications were encountered associated with free tissue transfers and the patient was able to take a soft diet three weeks after the final procedure.

Adult↗