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Gokhan Adanali

Publications and source records attributed to Gokhan Adanali.

15 recordsLinked to original sources
PubMed2003

Effects of hyaluronic acid-carboxymethylcellulose membrane on extraneural adhesion formation and peripheral nerve regeneration.

The goal of nerve repair in the peripheral nervous system is to increase the number of axons passing from proximal to distal stump, and to enable the regenerated axons to reach the end organ as soon as possible. In the present study, the effect of the membrane formed by a mixture of hyaluronic acid and carboxymethylcellulose (HA-CMC) on nerve regeneration and perineurial scar formation was investigated. Eighteen New Zealand rabbits were allocated into control (n = 9) and experimental groups (n = 9). In the control group, conventional nerve repair was carried out following the transection of the sciatic nerve, while in the experimental group, following repair of the nerve, the repair line was covered by HA-CMC membrane extending 1 cm beyond the distal and proximal ends. Nerve regeneration and extraneurial adhesion formation were compared between the two groups 3 months later. It was observed that adhesion in the surrounding tissues was significantly less in the experimental group than in the control group. Furthermore, morphometric analysis of specimens obtained from the distal parts of nerves showed that the number of axons with myelin was higher in the experimental group than in the control group, with a statistically significant difference. Histologic sections obtained from the nerve repair line demonstrated that extraneural and intraneural fibrosis was significantly lower in the experimental group. It was concluded that HA-CMC membrane had a favorable effect on nerve regeneration, as well as extraneural scar formation, encouraging the clinical application of HA-CMC following nerve injuries.

Animals↗
PubMed2003

Augmentation rhinoplasty with dermal graft and review of the literature.

Nasal augmentation required following a trauma or a rhinoplasty operation poses a challenging problem to many plastic surgeons. Currently, allografts and autologous tissues are used for nasal augmentation; however, an ideal technique has not yet been described. Although preferred for augmentation of different parts of the body, pure dermal graft use has not been described for nasal augmentation. The authors performed nasal augmentation using a dermal graft in 90 patients in their hospital between 1994 and 2000, and they followed up the patients for 6 months to 8 years. In this article, the early and late results of dermal grafts for nasal augmentation are presented, and their advantages and disadvantages are discussed with a review of the literature. It was concluded that the easily obtained dermal graft could be an appropriate alternative in nasal augmentation, though it has not been used widely for this purpose.

Adolescent↗
PubMed2002

Early and late effects of ischemic preconditioning on microcirculation of skeletal muscle flaps.

The present study was designed to investigate the early and late effects of ischemic preconditioning on muscle flap perfusion and reperfusion-induced skeletal muscle damage. Thirty-six Sprague-Dawley rats were divided into six experimental groups of six animals each. The cremaster muscle flap model and the intravital microscopy system were used to observe microcirculatory changes associated with ischemia-reperfusion injury and ischemic preconditioning. In groups 1, 2, and 3, microcirculatory measurements were taken on the same day; however, in groups 4, 5, and 6, measurements were taken a day after surgery. Group 1 served as a control. The cremaster muscle was prepared as a tube flap, subjected to an hour of perfusion without ischemia. In group 2 (ischemic preconditioning + ischemia group), the cremaster muscle tube flap was subjected to 30 minutes of ischemia and 30 minutes of reperfusion, followed by 4 hours of total ischemia. In group 3 (ischemia alone), the flap was submitted to 4 hours of ischemia alone. In group 4 (control), the cremaster muscle flaps were dissected out, preserved in the subcutaneous tunnel, and submitted to 24 hours of perfusion only. In group 5 (ischemic preconditioning + 24 hours of perfusion + 4 hours of ischemia), the ischemic preconditioning protocol was followed by 24 hours of perfusion and 4 hours of ischemia. In group 6 (24 hours of perfusion + ischemia), the same protocol was used as in group 5 without ischemic preconditioning. Functional capillary perfusion, and the diameters of the arterioles of the first, second, and third order were significantly increased in the ischemic preconditioning group during the early period, but not after 24 hours of perfusion. No differences in the red blood cell velocities of arterioles of the first, second, or third order were found in either the early-effect or late-effect groups. The numbers of rolling, adhering, and transmigrating leukocytes, however, were significantly lower in the ischemic preconditioning group at both early and late follow-up. Ischemic preconditioning of the skeletal muscle flap has both an early and a late protective effect against reperfusion injury. Ischemic preconditioning at the early interval significantly improves muscle flow hemodynamics of the flap and attenuates leukocyte-mediated reperfusion injury. After 24 hours of reperfusion, however, ischemic preconditioning failed to improve the flow hemodynamics of the flap, yet it still protected the skeletal muscle flap from leukocyte-mediated reperfusion injury.

Animals↗
PubMed2002

Late effects of TNF-alpha-induced inflammation on the microcirculation of cremaster muscle flaps under intravital microscopy.

In order to understand the microcirculatory changes and regulatory mechanisms governing passage of neutrophils from the vascular bed to the interstitial tissue during ischemia/reperfusion (I/R) injury, a key component of this injury, tumor necrosis factor-alpha (TNF-alpha)-induced inflammation was analyzed. Twenty-four Sprague-Dawley rats were divided into four groups, containing six animals in each. The effect of TNF-alpha-induced inflammation was studied at two different time points, early sequential and late. In the early-effect Groups 1 and 2, animals were given TNF-alpha and vehicle, respectively. Microcirculatory changes were recorded for 6 hr continuously. In the late-effect Groups 3 and 4, following TNF-alpha injection and vehicle, microcirculatory changes were measured 16 hr later. In the early-effect groups, the number of rolling and adhering leukocytes was increased immediately following TNF-alpha injection and remained elevated for the first 3 hr (p<0.05). The number of transmigrated leukocytes remained significantly increased throughout the first 6 hr (p<0.05) and returned to normal at 16 hr. In delayed-effect groups, a second peak in the number of rolling leukocytes was noted at 16 hr (p<0.05). The numbers of rolling and adhering lymphocytes, although remained at the baseline for the first 6 hr, was increased 2- and 1.5-fold at 16 hr, respectively (p<0.05). The number of perfused capillaries gradually decreased over time in the TNF-alpha-induced inflammation groups. A vasodilatory response was noted at the third and fourth order arterioles within the first 3 hr of measurement (p<0.05), but returned to normal afterward. The detrimental effects of TNF-alpha-induced inflammation during I/R injury could be prolonged up to 16 hr at the microcirculatory level of the muscle flaps.

Animals↗
PubMed2002

Flipper hand.

Explore the source record for details and available documents.

Adult↗
PubMed2002

Effects of different vascular patterns and the delay phenomenon on rat ventral island flap viability.

The objective of the current study was to investigate flap viability and to determine optimal delay time by designing various blood flow patterns in the superficial inferior epigastric (SIE) artery (A) and vein (V) flap model. Flaps measuring 7 x 7 cm were created in 42 Sprague-Dawley rats, which were divided into six groups. In group I rats (AV-AV), the flap was elevated based on the bilateral SIE vessels. In group II rats (AV-A), the flap was elevated based on the right SIE vessels and the left artery. In group III rats (V-AV), the flap was elevated based on the left-side vein whereas the SIE artery and vein were the pedicle on the right side. In group IV rats (V-A), the flap was elevated as a venous flap on the left side and was SIE artery based on the right side. In group V rats (AV-) the flap was elevated based on the right SIE artery and vein. In group VI rats (delay), the SIA artery and vein on the left side were ligated without elevation during the first session. The flap was elevated on the right SIE artery and vein 7 days after the delay procedure. Percentages of viable flap surface area were measured in millimeters with acetate paper on day 5 after surgery. The highest viability was seen in group I rats (96.14%), and the delay group had the second highest viable area (88.56%). The area that remained viable in group II was larger than that of group III (87.41% vs. 72.84%; p < 0.05). The least viable areas were observed in group IV. The percentage of viable flap area was significantly higher in the delay group when compared with group V rats (88.56 +/- 1.06% vs. 60.01 2.58%; p < 0.05). In conclusion, if the contralateral pedicle is ligated 7 days before SIE vessel-based island flap elevation, the flap can be used safely in a manner that crosses the median. Artery inflow of the flap is more important than venous outflow for improvement of flap viability on the contralateral side.

Animals↗
PubMedDate not supplied

Contribution of vitamin C administration for increasing lipolysis.

This experiment was designed to investigate whether addition of vitamin C to the solution used in tumescent technique of liposuction might increase lipolysis and whether increased fibrosis might improve skin retraction where liposuction did not work properly and the skin had poor retraction ability. Eighteen Sprague-Dawley rats were used in two groups. Both inguinal fat pads of rats with their vascular structures were elevated and the right inguinal fat pad was injected with 1 cc tumescent solution as a control and the left fat pad with a 1 cc vitamin C-tumescent solution. Histopathological examination showed that all fat pads injected with tumescent solution had normal adipocytes. Those injected with vitamin C-tumescent were shown to have extreme fibrosis and occasional adipocytes.

Adipose Tissue↗
PubMedDate not supplied

A new, T-shaped adaptor for easy, quick and efficient fat harvesting during liposuction.

Although there is a controversy about success and failure of autologous fat tissue transfers, it is a widely accepted method for soft tissue augmentation and is performed by many plastic surgeons as well as dermatologists all around the world. Its advantages are that it does not cause reactions, its absorption rates have been reduced by increased knowledge, experience, and techniques, it can yield good, long-term results, and there are now preservation techniques that allow reinjections when necessary. However, no single ideal technique has been determined. In this paper a new, simple, T-shaped adaptor for easy, quick, and efficient fat harvesting during liposuction is described. This study not only describes the clinical use of the adaptor, but also histologically examines its effects on fat cells under various vacuum pressures (-250 mmHg, -500 mmHg, -700 mmHg). The study shows that the cell structure of fat tissue harvested under medium power (with vacuum pressures of -250 mmHg and -500 mmHg) is not disrupted, while that of tissue harvested with a vacuum pressure of -700 mmHg was traumatized and occasional cell wall fragmentation occurred. In conclusion, it is shown that the T-shaped adaptor allows harvesting of the desired amount of fat tissue without causing trauma to fat cells when it is used with medium-power suction.

Adipose Tissue↗
PubMedDate not supplied

Cryopreservation of hair follicles at 20 degrees C: can it work in staged hair transplantation.

Androgenic alopecia is a serious problem for a large proportion of the population, especially males, and causes them to seek medical help. Many methods have been described for treatment of androgenic alopesia. Among them are punch grafts, strip grafts, scalp grafts, scalp reductions, tissue expanders, and flap combinations, and hair transplantations with minigrafts and micrografts. The latter has become popular in the last two to three decades and has been investigated extensively. Improvements in hair replacement with minigrafts and micrografts may allow an ideal result with a nearly normal appearance. However, hair replacement with these grafts has important disadvantages. It requires a long operational time and only a limited number of grafts can be placed in one session. In this study, we investigated morphological structures of micrografts stored at 4 degrees C and those stored at -20 degrees C. We found that morphological structures of the grafts stored at 4 degrees C started to be impaired in the fifth day, but that the morphological structures of the grafts stored at -20 degrees C remained unaltered for 15 days. If this method is put into practice, the use of minigrafts and micrografts available will not only obviate the second graft harvesting, but also allow reconstruction of a large area in a short period of time.

Adult↗