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Sakir Unal

Publications and source records attributed to Sakir Unal.

At least 19 recordsLinked to original sources
PubMed2006

An algorithm for deciding alternative grafting materials used in secondary rhinoplasty.

Severe middle vault deformity with disturbed nasal form and function is one of the most challenging procedures to correct in a secondary rhinoplasty. Reconstructing the deformity with autologous septal cartilage would be the primary choice of most surgeons, if it were always available. However in certain cases the lack of a sufficient quantity of autologous cartilage has forced surgeons to explore other viable options. This paper discusses our experience with the combined use of spreader and dorsal onlay grafts from various materials in the reconstruction of severe middle vault deformity in 110 patients. In follow up, (between 6 and 42 months; mean 21 months) all patients were noted to have improved in both aesthetics and function with no major complications noted. In summary, this study proposes that any engrafting material can be used safely when the proper surgical principals and technique are employed.

Adult↗
PubMed2006

The effect of pentoxifylline in treatment of skin degloving injuries: an experimental study.

BACKGROUND: Management of skin degloving injuries is still a problematic issue and the avulsed part of the skin may become necrotic. In this pilot study, we attempted to develop an experimental model for degloving injuries and investigated the efficacy of pentoxifylline, a well-known potent agent in enhancement of erythrocyte flexibility and tissue vascularization, in treatment of this injury model. METHODS: Degloving injuries were created in 15 rats' tails by circular puncturing of the skin at the middle of the tail and then applying moderate force to avulse the skin from the underlying tissue. Then, the skin was repaired back to its original position. No treatment was given in the first group (n=6). In the second group (n=3), 0.4cm(3) physiological serum was administered intraperitoneally for 10 days. In the third group (n=6), intraperitoneal 25mg/kg pentoxifylline was administered for 10 days. Tails were observed daily for 21 days and then examined histopathologically. RESULTS: At the end of the study, the avulsed segment of the skin became cyanotic and ulcerated in the first and the second group, and in the third group, the skin was intact. In histopathological examination, loss of superficial ephitelium and dense infiltration of inflammatory cells were seen in groups 1 and 2, and the skin layers were normal in the group 3. CONCLUSION: Pentoxifylline improved tissue preservation and was proved to be highly beneficial in treatment of skin degloving injuries.

Animals↗
PubMed2006

Superficial basal cell carcinoma of the scalp mimicking seborrhoeic dermatitis.

Superficial basal cell carcinomas (BCC) comprise 9% to 11% of BCC, and are commonly found on the trunk or limbs. We report a case of a superficial BCC on the scalp that was misdiagnosed and treated as seborrhoeic dermatitis. Any erythematous plaque-type lesion of long duration must have superficial BCC considered in the differential diagnosis.

Basal Cell Carcinoma↗
PubMed2006

A cadaver study in preparation for facial allograft transplantation in humans: part I. What are alternative sources for total facial defect coverage?

BACKGROUND: Reconstruction of facial defects in burn, trauma, and head-neck cancer patients is challenging. The lack of autogenous tissue availability and the need to match facial texture and color are major concerns. METHODS: Anatomical dissections were performed to search for alternative sources for facial-scalp reconstructions in five cadavers. The composite facial-scalp flaps, radial forearm, anterolateral thigh, bipedicled deep inferior epigastric perforator, and bipedicled scapular-parascapular flaps were harvested. The total surface areas of the facial defects and alternative traditional flaps were measured. RESULTS: The mean surface area for combined facial-scalp flaps and facial flaps without scalp was 1192 +/- 38.2 cm and 675 +/- 22.3 cm, respectively. When compared with the total surface area of the facial-scalp flap, it was found that the radial forearm flap covered 13 +/- 2.58 percent, the anterolateral thigh flap 19 +/- 3.72 percent, the bipedicled deep inferior epigastric perforator flap 35 +/- 1.56 percent, and the bipedicled scapular-parascapular flap 48 +/- 4.64 percent of the defect, respectively. When measurements were taken for coverage of the facial defect without scalp, it was found that the radial forearm flap covered 24 +/- 4.0 percent, the anterolateral thigh flap 34 +/- 6.50 percent, the bipedicled deep inferior epigastric perforator flap 62 +/- 3.03 percent, and the bipedicled scapular-parascapular flap 84 +/- 8.30 percent of the defect, respectively. CONCLUSIONS: The authors' cadaver dissection confirmed that none of the conventional cutaneous autogenous flaps are able to cover total facial defects. Currently, the best option for reconstruction of the full facial defect is the autogenous bipedicled scapular-parascapular flap because of its large size and texture. However, perfect match of facial skin texture, pliability, and color can only be achieved by transplantation of the facial skin allograft from the human donor.

Aged↗
PubMed2006

A cadaver study in preparation for facial allograft transplantation in humans: part II. Mock facial transplantation.

BACKGROUND: The authors have performed mock facial transplantation by harvesting total facial-scalp flaps from donors and transferring them to recipient cadavers. METHODS: A total of 10 fresh human cadavers were dissected. In the donor, the authors have measured the time of facial-scalp flap harvesting, and the length of the arterial and venous pedicles and sensory nerves that were included in the facial flaps. In the recipient, the authors have evaluated the time of facial skin harvest as a monobloc full-thickness graft, the anchoring regions for the inset of the donor facial flaps, and the time sequences for the vascular pedicle anastomoses and nerve coaptations. RESULTS: In the donor cadaver, the mean harvesting time of the total facial-scalp flap harvest was 235.62 +/- 21.94 minutes. The mean length of the supraorbital, infraorbital, mental, and great auricular nerves was 1.5 +/- 0.15, 2.46 +/- 0.25, 3.02 +/- 0.31, and 6.11 +/- 0.42 cm, respectively. The mean length of the external carotid artery, the facial vein, and external jugular vein was 5 +/- 0.32, 3.15 +/- 0.32, and 5.78 +/- 0.5 cm, respectively. In the recipient cadaver, the mean harvesting time of facial skin as a monobloc full-thickness graft was 47.5 +/- 3.53 minutes. The mean time for the preparation of the arterial and venous pedicles and sensory nerves for the future anastomoses and coaptation was 30 +/- 0 minutes. The mean time for facial flap anchoring was 22.5 +/- 3.53 minutes. The total mean time of facial mock transplantation without vessels and nerve repair was 320 +/- 7.07 minutes (5 hours 20 minutes). CONCLUSION: Based on anatomical dissections in this cadaver study, the authors have estimated the time and sequence of facial flap harvest and inset to mimic the clinical scenario of the facial transplantation procedure.

Aged↗
PubMed2006

Composite hemiface/calvaria transplantation model in rats.

BACKGROUND: Extensive craniomaxillofacial deformities including bone and soft-tissue defects are always challenging for reconstructive surgeons. The purpose of this study was to extend application of the face/scalp transplantation model in the rat by incorporation of the vascularized calvarial bone, based on the same vascular pedicle, as a new treatment option for extensive craniomaxillofacial deformities with large bone defects. METHODS: Seven composite hemiface/calvaria transplantations were performed across major histocompatibility complex barrier between Lewis-Brown Norway and Lewis rats. Seven donor and seven recipient rats were used in this study. Hemicalvarial bone and face grafts were dissected on the same pedicle of the common carotid artery and jugular vein and were transplanted to the deepithelialized donor faces. All rats received tapered and continuous doses of cyclosporine A monotherapy. Evaluation methods included flap angiography, daily inspection, computed tomographic scan, and bone histology. RESULTS: Flap angiography demonstrated the vascular supply of the bone. The average survival time was 154 days. There were no signs of rejection and there was no flap loss noted at 220 days posttransplantation. Bone histology at days 7, 30, 63, and 100 after transplantation revealed viable bone at all time points, and computed tomographic scans taken at days 14, 30, and 100 revealed normal bones without resorption. CONCLUSIONS: For extensive face deformities involving large bone and soft-tissue defects, this new osteomusculocutaneous hemiface/calvaria flap model may serve to create new reconstructive options for covering during one surgical procedure.

Angiography↗
PubMed2005

Relationship between ABO blood groups and skin cancers.

Studies of associations between various cancers and the ABO blood groups have shown elevated relative risks for some categories of disease. To date, no report has evaluated the relationship between the ABO blood groups and the skin cancers. To investigate this association, we conducted a retrospective study of premalignant and malignant tumors diagnosed in Turkey. All tumors were histologically confirmed. Blood information was obtained for 98 individuals with premalignant and malignant skin tumors, and the distribution of ABO and Rh blood type for cases was compared with that of 419 healthy blood donors from the same geographic area. Although patients with blood group A were higher, group 0 lower than in controls, the differences were not significant. The distribution of Rh factor, blood group B and AB among cases and controls also did not differ significantly. We found a significant relationship between age and skin cancer (p=0.0001). Old patients had 1.238 times higher risk for skin cancer. Further studies in larger series on blood group antigens are needed to elucidate the relationship between these antigens and skin cancer.

ABO Blood-Group System↗
PubMed2005

The additive effects of carnitine and ascorbic acid on distally burned dorsal skin flap in rats.

BACKGROUND: The purpose of this study was to determine the effects of combined use of L-carnitine and vitamin C on partially burned skin flap in an experimental rat model. MATERIAL/METHODS: In the rat dorsal skin, a 10 x 3 cm flap was marked. The most distal 3 x 3 cm part was burned to full thickness. Twenty-four rats were randomized into four groups with 6 animals in each. Group 1 was simply followed up. Group 2 was given 0.5 mg/kg vitamin C per day for 7 days, group 3 100 mg/kg carnitine per day for 7 days, and group 4 both carnitine and vitamin C. On the eighth postoperative day, the animals were sacrificed and examined. The surviving and necrotic areas were determined by macroscopic examination and measured with a planimeter. RESULTS: The areas of flap necrosis were measured. The median surviving areas and areas of flap necrosis, respectively, of the groups were: group 1, 16.0 cm(2) and 14.0 cm(2); group 2, 18.25 cm(2) and 11.75 cm(2); group 3, 20.0 cm(2) and 10 cm(2) ; and group 4, 23.75 cm(2) and 6.25 cm(2). The surviving areas of the groups were found to be significantly different (p=0.000). CONCLUSIONS: The risk of ischemia-induced necrosis in flap attempts made in damaged tissues may be reduced by the combination of two promising agents, L-carnitine and vitamin C. L-carnitine appears to be the major contributing factor that reduces necrosis, and vitamin C an additive agent.

Animals↗
PubMed2005

The relationship between patient stress and the blood levels of acute phase proteins in rhinoplasty: the report of a prospective study.

OBJECTIVE: This study aims to interrogate the relationship between patient stress and the levels of acute phase proteins (APP) in rhinoplasty. METHODS: Twenty-six primary rhinoplasty patients were asked about the most stressful step of the rhinoplasty process, which were (1) deciding on the operation, (2) waiting in the preoperative room, (3) the first few postoperative hours, and (4) withdrawing the nasal pack, in order beginning from the most stressful one, preoperatively, and then postoperatively. C-reactive protein (CRP), alfa-1-acide glycoprotein (AAG), ceruloplasmin (CER), haptoglobulin (HPT), and alfa-1-antitrypsin (AT) have been studied in blood to detect a relation between the patient stress and the levels of APP. RESULTS: Preoperatively, the "imagined" most stressful step was Step 4 (61.53%). Postoperatively, the "declared" most stressful step was Step 3 (50%). The blood levels of APP matched with the imagined rather than the declared stress. CONCLUSION: Patient stress could be a preoperative issue, which should be eliminated preoperatively. Detailed description of the surgery and some pharmaceutics can inhibit the negative effects of the stressors and have a contribution to patient comfort.

Acute-Phase Proteins↗
PubMed2005

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

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.

Adult↗
PubMed2005

New surgical approach in facial transplantation extends survival of allograft recipients.

We have previously developed a composite total face-scalp allotransplantation model based on bilateral common carotid arteries (CCA) and external jugular veins. To decrease the mortality rates, different modifications of arterial anastomoses in the facial allograft recipients are presented. Eighteen full face-scalp allograft transplantations were performed across major histocompatibility (MHC) barriers between ACI (RT1) donors and Lewis (RT1) recipients. Bilateral CCA and bilateral external carotid arteries of the recipients were used as recipient vessels to vascularize the flap in 5 and 4 transplants, respectively. In 9 transplants, unilateral CCA of the recipients were used to vascularize the face/scalp flap. All the animals received CsA 16 mg/kg/d Sc, which was tapered over 4 weeks to 2 mg/kg/d. In transplants utilizing bilateral CCA, the survival rate of the animals was very short. Transplants in which unilateral CCA were used yielded 100% survivals over 200 days posttransplant. These modifications of arterial anastomoses have significantly improved survival of facial allograft recipients.

Anastomosis, Surgical↗
PubMed2005

Strategies for tolerance induction in nonhuman primates.

Recent advances in the field of reconstructive surgery and immunology resulted in increased interest in composite tissue allograft (CTA) transplantation. Up to date, more than 50 CTA transplants have been reported in humans. A significant number of experimental studies on CTA transplants under different protocols of tolerance-inducting strategies have been reported in small-animal models. There is however, a limited number of CTA transplants performed in nonhuman primates. To reach the ultimate clinical success in CTA transplantation, more experimental studies on tolerance induction in nonhuman primates are needed to apply these immunomodulatory protocols to CTA transplants in humans. In this review, strategies for tolerance induction in the nonhuman primate model in solid organ and CTA transplants are presented in 3 major categories: chimerism induction, T-cell depletion, and costimulatory receptor blockade.

Animals↗
PubMed2004

Enhanced frontalis sling with double-fixed, solvent-dehydrated cadaveric fascia lata allograft in the management of eye ptosis.

The article describes an enhanced frontalis sling procedure in the management of blepharoptosis with poor or no levator function. This modified method were used in the care of three patients and based on the principal of two-point fixation of the graft material that was prepared from solvent-dehydrated cadaveric fascia lata onto the frontalis muscle. After more than 1 year of follow-up, no recurrence was noted. With no extra incision over the skin, this surgical approach could be useful in the correction of difficult ptosis cases.

Adolescent↗