Microvascular reconstruction of a giant encephalocele defect in a 10-week-old infant.

Microvascular reconstruction of a cranial defect in a 10-week-old infant, which is the youngest case in the literature, is reported. A latissimus dorsi free muscle flap was transferred to cover the defect and a split thickness skin graft was placed over the muscle flap. Despite the successful flap transfer in this case, microvascular reconstruction in an infant has its own risks and infants should be discussed as a separate entity apart from the other pediatric patients.     

Effects of hyperbaric oxygen treatment and heparin on the survival of unipedicled venous flaps: an experimental study in rats

The effects of hyperbaric oxygen (HBO) and heparin on the survival of the rat inferior epigastric venous flap were investigated. Preliminary transcutaneous oxygen measurements showed that partial oxygen pressure values of venous flaps increased at 2.5 ATA pressure while inhaling 100% oxygen. During the experiment, 128 venous flaps of two different sizes and 50 composite grafts were prepared bilaterally in 89 rats. Perivenous areolar tissue was removed from the pedicle vein in all flaps. Half of the venous flaps were isolated from the wound bed. Initial flap perfusion was tested by fluorescein injection during flap elevation. Four treatment groups were created: control, heparin, HBO, and HBO+heparin. After 6 days of treatment, the mean surviving flap area was calculated for each group. Surviving flaps were reelevated, final flap perfusion was tested by fluorescein injection, and flaps were harvested for histological examination. The mean survival rates of the HBO (26.56%) and the HBO+heparin (36.87%) groups were significantly higher than the control (0%) and the heparin (0%) groups (p<0.01). None of the composite grafts survived. Smaller flaps and nonisolated flaps survived better, although not significantly (p>0.05). Veins were enlarged both clinically and histologically. Fluorescein uptake was delayed during initial flap elevation but was normal during reelevation. These findings imply that the rat inferior epigastric venous flap may be an ischemic flap with capillary circulation through a single venous pedicle, but it needs HBO treatment to survive, especially during the acute period. Heparin treatment, reducing the flap size, and presence of a vascular wound bed also improve survival rates.     

A neurocutaneous island flap model: an experimental study in rats

Neurocutaneous flaps have been popularized recently in clinical reconstructive surgery. However, controversies exist concerning their anatomy and physiology. The particular role of neural vasculature in the survival of these skin flaps is also quite undefined in the experimental setting, and additional studies on this subject are necessary. The goal of this study was to describe a neurocutaneous flap in a rat model and to investigate its blood supply. Thirty male Sprague-Dawley rats weighing 300 to 350 g were used in this study, which was conducted in two stages. During the first stage, the lower extremities of 10 rats were dissected for the anatomic study of the neurocutaneous flap. A constant cutaneous nerve innervating the anterolateral thigh skin was exposed. It arose either from the saphenous nerve or the superficial epigastric nerve and was accompanied by a constant longitudinal arterial plexus. The tiny neural vessels were conveyed by the superficial fascia along their course. A 30 x 30-mm cutaneous island flap, which was based only on the cutaneous nerve with its accompanying vessels and a strip of superficial fascia, was raised on the anterolateral thigh skin using an operating microscope. The well-perfused skin territory was marked after sodium fluorescein injection. The stained skin territory was located centrally and medially on the whole island flap, and it was approximately 10 x 20 mm. This finding was confirmed by the qualitative assessment of the vascularity for this skin territory in microangiography. After studying the pedicle anatomy and determining the optimal viable skin island, the second stage of the study was performed. The remaining 20 rats were divided into two groups. In the experimental group (N = 10), a neurocutaneous island flap (10 x 20 mm) was outlined on the anterolateral aspect of the thigh at its middle third. It was designed in such a way that its short and long axes lay in the center of the distance between the anterior superior iliac spine and the anterior aspect of the knee joint. After identification and dissection of the neurovascular pedicle, the flap was raised in a lateral-to-medial direction without including the deep fascia. At this point the flap remained connected only by the pedicle and a strip of superficial fascia surrounding it. It was sutured in the same place. In the control group (N = 10), the pedicle of the flap was severed and the skin island was sutured back as a composite graft. All the experimental flaps survived well. In the control group, none of the flaps survived except one that was partially viable. The flaps in the experimental group were reelevated as neurocutaneous island flaps on day 7 for microangiographic study, and specimens were processed for histologic staining. Microangiography revealed the extent of neural vasculature and vascularization of the skin through cutaneous perforators. Histologic investigation demonstrated the neural vessels that were related closely to the superficial fascia. The authors propose a neurocutaneous island flap model in the lower extremity of the rat in which the survival of the flap depended mainly on the neural arterial supply. It was also demonstrated that the superficial fascia played a role as a connective tissue framework for conveying tiny neural blood vessels to reach the skin. This model may serve as a reproducible and reliable neurocutaneous island flap model for additional studies in this field.     

The effect of defective early phase insulin secretion on postload glucose intolerance in impaired fasting glucose

Impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) are two risk groups for type 2 diabetes. Type 2 diabetes is characterized by both impaired insulin secretion and insulin resistance but their relative contribution to the development of hyperglycemia may differ due to heterogeneity of the disease. Combined glucose intolerance (CGI), on the other hand, seems to represent a more advanced stage of prediabetes that bears a distinctly higher risk of progression to diabetes and its comorbidities. This study has the aim to compare isolated IFG and CGI categories with respect to the degree of early phase insulin secretion abnormalities and insulin resistance. Subjects who had IFG (fasting glucose: 110-126 mg/dl) were included in the study. A 75-g oral glucose tolerance test (OGTT) with insulin response was done and subjects were classified according to the WHO criteria. Six subjects were excluded because they had diabetic glucose tolerance. A total of 66 patients (53.4 +/- 11.1 years, female/male: 48/18) were divided into two groups according to their glucose tolerance in OGGT (Group 1: isolated IFG and group 2: CGI). Early phase insulin secretion was measured by intravenous glucose tolerance test (IVGTT) and OGTT. Insulin resistance was assessed by the R value of the homeostasis model assessment (HOMA). We did not find any statistically significant difference between groups according to age, gender, body mass index (BMI), fasting glucose, fasting insulin, insulin-AUC (0-180 min) and HOMA-R values. In OGGT there was no statistically significant difference between 0', 30', 60' and 90' insulin levels of the groups; only 120' and 180' insulin levels were higher in CGI than in IFG group (p<0.05). In IVGTT, there was no statistically significant difference between glucose levels of the groups. Furthermore, insulin response to intravenous glucose was higher in IFG than in CGI (p<0.05). Our data demonstrate that isolated IFG and CGI are similar with respect to the degree of insulin resistance, and that subjects with CGI had a more prominent deficit in early phases of insulin secretion.     

Relationships between sex steroids of the seminal fluid and milt quality parameters of Persian sturgeon, Acipenser persicus Borodin, 1897

To investigate the role of sex steroids of the seminal fluid on sperm quality, the relationships between sex steroids and milt quality parameters (sperm motility and sperm production) were investigated in the Persian sturgeon. The seminal fluid levels of 17α,20β,21-trihydroxy-4-pregnen-3-one (20βs), and 11-ketotestosterone (11-KT) had positive relationships with sperm motility characteristics (percentage and duration of motility) and sperm density. Also, no relationships were found between other sex steroids including: Testosterone (T), progesterone (P), 17α-hydroxyprogesterone (OHP), and milt quality parameters. The good correlation of 20βs and 11-KT of the seminal fluid with sperm motility and sperm density suggests that these steroids may be important hormones involving in final maturation of the Persian sturgeon spermatozoa.     

Comparison of preoperative anxiety in reconstructive and cosmetic surgery patients

Surgery is a serious stressor and a cause of anxiety for the patients. Reconstructive surgery patients are mostly operated on because of certain functional impairment or disability; on the contrary, cosmetic surgery patients do not have any physical impairment and they are operated on because of mostly psychologic reasons. The aim of this study was to compare the anxiety levels in the reconstructive surgery patients and cosmetic surgery patients preoperatively. Thirty-two patients in the reconstructive surgery group and 30 patients in the cosmetic surgery group were included in the study. State Trait Anxiety Inventory was used to measure the anxiety levels in these 2 groups preoperatively. The 2 groups were similar in characteristics such as age, gender distribution, number of previous operations, and trait anxiety scores. Mean state anxiety scores obtained for the reconstructive surgery group was 38.0 +/- 8.7, while it was 44.2 +/- 10.79 for the cosmetic surgery group (t test, degrees of freedom = 60, P = 0.015). This study reveals that preoperative anxiety levels in the cosmetic surgery patients are higher than those of the reconstructive surgery patients. Therefore, adequate preoperative preparation for cosmetic surgery should include attempts to cope with anxiety. Anxiolytics may be used more liberally and professional psychologic assistance may be required.     

Fat prefabrication using a fascial flap in the rat model.

Prefabrication of fat tissue using a fascial flap based on the superficial inferior epigastric artery was studied in rats. First, the superficial inferior epigastric fascia was transposed over the inguinal fat pad. Two weeks later fascia and fat were elevated together as a prefabricated composite flap. At this stage, a pilot study was done in ten rats and perfusion of the flaps was tested with fluorescein. After confirming fluorescein staining of the prefabricated flaps, the study continued with experimental and control groups of rats. In the experimental group, prefabricated flaps were transposed to the subcostal area. In the control group, the pedicles of the flaps were severed, creating composite grafts. These grafts were transferred to the subcostal area in the same manner as in the experimental group. One week later the flaps were re-elevated and grafts were exposed. Fluorescein tests and Indian ink microangiography were carried out. In the experimental group, the flaps were stained, while grafts in the control group were not stained. Fat and fascia were found to be viable in the experimental group, while they were necrotic in the control group on histopathological examination. Based on these findings, we can conclude that the prefabrication of fat by vascular fascia is successful and may have application in plastic surgery.     

Innervation of skin grafts over free muscle flaps.

Skin grafts regain their sensory innervation from the graft bed by the regeneration of nerve endings. Although some clinical studies report sensory recovery in skin grafts implanted on free muscle flaps, the mechanism of recovery is obscure. The purpose of this study was to investigate nerve regeneration in experimental skin grafts on free muscle flaps to elucidate this phenomenon. Thirty-eight male Sprague-Dawley rats, weighing 450-550 g were used in the study. The rat gracilis muscle flap was the free flap model transferred from one groin to the other using microvascular anastomoses. Full-thickness skin grafts harvested from the abdomen were used to cover the free muscle flaps after transfer. Four study groups were formed: Group I (n = 10): Free muscle flaps were transferred without any nerve anastomosis; Group II (n = 10): Free flaps transferred with the anastomosis of the muscle's motor nerve to a sensory nerve at the recipient site; Group III (n = 10): Free flaps transferred with the anastomosis of the muscle's motor nerve to a motor nerve at the recipient site; Group IV (n = 8): Skin grafts were placed directly on the fascia layer over the medial hindlimb muscles and served as controls. The specimens were harvested for histologic examination after 12 weeks. Histologic examination was performed to visualise regenerating nerve endings using H&E, S100, Luxol Fast Blue and tyrosine hydroxylase staining. The specimens were categorically scored according to the staining pattern of neural structures around pilosebaceous units and statistical comparisons were performed by using paired t-test. Skin grafts in both Group II and Group III markedly received tyrosine hydroxylase at the base of their pilosebaceous units in many of the specimens and functional nerve twigs could also be traced from the muscle layer to the overlying skin graft. In contrast, the skin grafts in Group I did not show any nerve function in the central parts. The overall staining scores of Groups II, III and IV were significantly higher than Group I (P < 0.05; P < 0.001; P < 0.05, respectively). There was no statistically significant difference between other groups. No myelinated nerve fibres could be detected in any of the skin grafts with Luxol Fast Blue technique. It was concluded in the present study that skin grafts over reinnervated free muscle flaps can develop significantly better innervation than skin grafts over non-innervated muscle flaps. However, the activity in skin appendages indicating nerve regeneration may only imply a gross sensation and in the absence of any myelinated nerve fibres transmission of finer sensation cannot be expected in any of the study groups.