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H E Ozgentaş

Publications and source records attributed to H E Ozgentaş.

7 recordsLinked to original sources
PubMed2001

Perforator-based flap in rats: a new experimental model.

A new type of flap, the perforator-based flap, has been described in the last decade. It has been used successfully as a pedicle or free flap by many plastic surgeons. There is no animal model for research, although these flaps have gained popularity in clinical use. We created a perforator-based flap model in the rat (a perforator-based flap group and two control groups; 10 rats in each group) and evaluated the survival characteristics of the new flap. The abdominal skin flap was elevated based on the second perforator of the right superior deep epigastric artery and then sutured to its original bed. In the first control group, the same flap was elevated with a subcutaneous pedicle without any perforator; in the second control group, a right-sided, random-pattern pedicle abdominal skin flap with the same dimensions and location was elevated and sutured to its original bed. Flap survival was studied, and microangiography and histologic studies were performed. The amount of viable skin in the three groups was compared 1 week later. The area of surviving skin paddles in the experimental group ranged from 74 to 83 percent; in the first control group, it was 0 percent; and in the second control group, it ranged from 29 to 44 percent (p < 0.001 and p < 0.001, respectively). There was a predictable and constant area of necrosis in the model. The results of this study demonstrate that most of the abdominal skin of the rat can survive on the basis of a single musculocutaneous perforator vessel. This flap can be easily elevated, and it can be used as a reliable model for flap research.

Abdomen↗
PubMed2000

Effect of the delay phenomenon in the rat single-perforator-based abdominal skin flap model.

During the last decade, innovations in reconstructive surgery have presented a new type of flap called the "perforator-based flap." Perforator-based flaps became useful alternatives for solving difficult problems. In the authors' previous study, they created a single musculocutaneous perforator-based abdominal skin flap. In their current study they evaluate the effect of various surgical delay procedures on this model. They divided 32 Sprague-Dawley rats equally into four groups (one control group and three delay groups). Three different delay procedures were employed in the delay groups. In one group, only the flap boundaries were incised (delay group 1). In the other delay groups, flap boundaries were incised and the contralateral (opposite side of the pedicle, delay group 2) or ipsilateral (pedicle side, pedicle left intact; delay group 3) musculocutaneous perforators were ligated. The period of delay was 1 week in all groups. After 1 week, a single-perforator-based abdominal skin flap was elevated as in the control group. One week after the final procedure, surviving skin areas were calculated and microangiograms were acquired. The mean surviving skin area was 75% +/- 3% (standard deviation) in the control group, 97% +/- 3% in delay group 1, 81% +/- 6% in delay group 2, and 96% +/- 3% in delay group 3. Delay group 2 showed substantial necrosis 1 week after the delay procedure and was thus excluded from the study. Results were analyzed using one-way analysis of variance, and post hoc analyses were performed using Tukey's multiple comparison test. The authors observed the advantages of the delay phenomenon in the two delay groups (p < 0.05). Microangiograms were examined grossly, and a marked difference between the two delay groups and the control group was observed. Many dilated choke vessels were seen in delay groups 1 and 3. Incising the flap boundaries with or without ligating the ipsilateral perforators (keeping the pedicle intact) 1 week before harvesting single-perforator-based abdominal skin flaps in the rat results in a delay effect. Conversely, incising the flap boundaries and ligating the contralateral perforators have no delay effect in this model.

Abdomen↗
PubMed1995

Prefabrication of a secondary TRAM flap.

A secondary TRAM flap was prefabricated in a rat model using the rectus muscle. The right rectus muscle was elevated as an inferiorly pedicled muscle flap in one experimental group (n = 6) and as a superiorly pedicled muscle flap in a second group (n = 5) and then sandwiched between a silicone sheet and the abdominal skin. Two weeks later, the abdominal skin and attached rectus muscle were elevated over the silicone sheet as a secondary TRAM flap. The surviving skin paddle areas of these prefabricated TRAM flaps were compared with superiorly (n = 7) and inferiorly (n = 8) pedicled TRAM flaps in a control group. One-way analysis of variance did not show significant differences between groups (p = 0.07). TRAM flap prefabrication in the rat model yields a skin paddle survival area comparable to that of a conventional TRAM flap, and it is possible to perform this procedure without using the anterior rectus sheath.

Abdominal Muscles↗
PubMed1994

A comparison of soft-tissue substitutes.

The fate of the Zyderm II, Zyplast, Vicryl, and chromic gut was histologically examined up to 1 year following subcutaneous implantation into rats. Our data demonstrated both Zyderm II and Zyplast to be inert materials without inflammatory response; there was no difference in long-term persistence between these two collagens. Both Vicryl and chromic gut implants caused an intense inflammatory response at 1 month, and Vicryl was completely resorbed before 6 months. The degree of inflammation associated with chromic gut diminished over time, and approximately 67% of the material persisted without reaction up to 1 year.

Animals↗
PubMed1994

Study of the delay phenomenon in the rat TRAM flap model.

Partial flap necrosis is frequently associated with the pedicled TRAM flap in the clinical setting. We created a TRAM flap model in rats (one control group and four delay groups; n = 8 in each group) and used a variety of flap delay techniques and vascular manipulations in an effort to increase the surviving area of the flap. The areas of surviving skin paddles in the five groups ranged from 4.4 cm2 in the control group to 9.9 cm2 in one of the delay groups. Analysis of variance and Tukey's pairwise comparisons indicated that delay groups II, III, and IV differed significantly from the control group (ANOVA F = 15.99, p < 0.001; Tukey experimental ER = 0.05, individual ER = 0.0068; critical value = 4.07). Ligation of the superficial inferior epigastric vessels and deep superior epigastric vessels (dominant pedicle) 1 week before TRAM flap surgery increased the area of survival of the skin paddle significantly in the rat model. The procedure is relatively easy to perform, and our laboratory findings should be readily reproducible in clinical practice.

Animals↗
PubMed1994

Development of a TRAM flap model in the rat and study of vascular dominance.

To investigate the suitability of the rat TRAM flap model for human TRAM flap research, we designed four different TRAM flaps with 10 x 3 cm rectangular skin paddles in rats: type 1 (n = 6), superior TRAM flap with unilateral superior rectus muscle pedicle; type 2 (n = 6), superior TRAM flap with unilateral inferior rectus muscle pedicle; type 3 (n = 6), inferior TRAM flap with unilateral superior rectus muscle pedicle; and type 4 (n = 6), inferior TRAM flap with unilateral inferior rectus muscle pedicle. We elevated and sutured back the TRAM flaps and measured the survival skin paddle areas. Our study demonstrated that in the rat TRAM flap model, the superior deep epigastric vessels are a more important source of vascularity for the skin paddle than the inferior deep epigastric vessels. A 5-cm lateral extension from the midvertical line was enough to cause some distal necrosis in every flap. A cephalically placed, inferiorly pedicled rat TRAM flap (type 2) has the smallest area of skin paddle survival; we concluded, therefore, that this flap placement is the most suitable for TRAM flap research.

Animals↗