No abstract

Injection of aspirated fat is now the most commonly used technique for the filling of depressed areas. Partial absorption of the injected fat is the main limitation of this procedure. Cariel T.M. is an enriched serum-free cell culture medium, its ability to enhance the survival of human aspirated fat grafts was investigated in the nude mouse model. A volume of 0.75-cc Cariel preprocessed fat was injected under the scalp skin of 16 nude mice in the experimental group, and the same volume of saline preprocessed fat was injected to 15 control group of mice. Significant maintenance of the weight, 46 percent in the experimental group compared with 29 percent in the control group (p < 0.008), and the volume, 44 percent in the experimental group compared with 31 percent in the control group (p < 0.026), was observed, after 15 weeks, in this newly used model. It seems that addition of the nutrients enriched with anabolic hormones enabled the survival and take of more adipose cells in the graft.

Because of the widespread reliance on SMAS tightening procedures in present-day face lift surgery, a study was undertaken to examine the physical properties and microscopic structure of both virginal (40 specimens) and reoperated (8 specimens) SMAS tissue. The findings could be of practical value to the surgeon and are reported herewith: First, the SMAS is a composite fibrofatty layer comprising collagen and elastic fibers interspersed with fat cells. Second, microscopic appearance shows a considerable amount of elastic fibers in close relationship to the collagen fibers. Third, on scanning electron microscopy, the collagen fibers in the virginal SMAS show a convoluted appearance similar to that found in the dermis. In the reexcised SMAS tissue, there is some evidence of parallelization of the collagen fibers as seen in the stretched dermis. Fourth, mechanical testing (Instron), i.e., a series of loading/unloading tests at various rates and amplitudes, and stress relaxation tests were performed on samples of preauricular skin and SMAS. These indicated definite viscoelastic properties for both sets of specimens, with the tendency of an increased stiffness and a reduction in viscoelastic effects on repeated working of the samples. Overall, the mechanical behavior of both tissues was somewhat similar, the viscoelastic effects in SMAS being less pronounced. A nonlinear viscoelastic model is under development to represent the behavior of both tissues. The implications of these results may help to explain the slackening effect observed in some postoperative patients.

Silicone gel and silicone occlusive sheeting are widely used at present for the treatment of hypertrophic and keloid scars, without any scientific explanation as to their mode of action. In a recent paper the possibility was raised that static electricity generated by friction-activated silicone sheeting could be the reason for this effect, and that it can, with time, cause involution of hypertrophic and keloid scars. The objective of this study was to test this hypothesis and to observe whether a continuous and also an increased negatively charged static-electric field will shorten the treatment period. A device to implement these requirements gradually evolved over a 5-year period. A number of prototypes were tested until the final product was attained. Some of the patients in this study were treated initially with a silicone sponge inserted in the cushion. Later this version was changed to the final design described herein. A silicone cushion was developed with the purpose of increasing a negative static-electric charge to accelerate the regression process. The cushion is custom-made using a silicone occlusive sheeting envelope of 0.75-mm thickness, which does not deteriorate with use, and is partially filled with high viscosity silicone oil. Its edges are sealed, and its size is designed to extend a little beyond the scarred area. Static electricity readings, generated by activating the cushion by pumping action with the fingers, stretching or deforming the cushion, are invariably much higher when compared with those obtained with silicone occlusive sheeting and silicone gel sheeting. The interaction between the negatively charged ions of the cushion and the ionic charges of the tissue fluids may be the critical factor in achieving hypertrophic and keloid scars involution. Of the 30 patients enrolled in the study, 3 patients dropped out. Treatment with the silicone cushions yielded 63.3 percent cessation of itching and burning followed by pallor and flattening of the scar, some markedly so, over a few weeks to 6-month period. An additional 26.6 percent had their scars resolved in up to 12 months of treatment. Good contact of the cushion over the scar has been shown to be important in this clinical trial, and much creativity is needed for making elastic strap bindings that ensure this contact. The clinical trials extended over a 12-month period. Ten patients (33.3 percent) who had recalcitrant scars with little response to the use of the silicone cushion were given intralesional corticosteroid injections, in addition to the continued use of the cushion, resulting in a fairly rapid resolution of these scars over a period of months to a year.

A defined, serum-free cell culture medium supplemented with nonsteroidal anabolic hormones, insulin, thyroxin, and growth hormone was found to accelerate wound healing by stimulating vascularized granulation tissue formation, epithelialization, and angiogenesis. The aim of this work was to study the effect of cell culture medium on the survival rate of cephalically based random dorsal skin flaps in an animal model. A total of 77 Sprague-Dawley rats were randomized into five treatment groups: pharmacologic delay with cell culture medium, flap enhancement with cell culture medium, surgical delay, biological delay with saline, and control. Statistically significant differences in distal flap necrosis were found among all groups (p<0.003). The rats treated with cell culture medium before flap elevation showed a significant increase in flap viability: a survival rate of 83 percent, compared with the control group, which demonstrated a survival rate of only 58 percent (p<0.0001). The surgical delay and the groups treated with cell culture medium yielded similar results with no significant difference between them. This study indicates that preoperative injection of cell culture medium may play a role in decreasing skin flap necrosis.

The chick chorioallantoic membrane (CAM) is a common model for studying biological processes, but descriptions of the CAM circulatory system and especially experimental preparations of the CAM in shell-less eggs are both scant and controversial. We studied the CAM structure and the three-dimensional spatial configuration of the CAM vessels using five methods: in vivo stereoscopic observations, whole-mount preparations, histological sections, corrosion cast microinjection techniques and the reconstruction of a three-dimensional wax model. Our findings show that the CAM consists of a superficial two-dimensional layer composed of a network of a very dense capillary mesh, floating over and enclosing a deeper three-dimensional space in which medium and larger free-floating vessels are seen to supply and drain the superficial layer. It is interesting to note that no tips or sprouts of blood vessels were observed during the development of the CAM vessels. In a shell-less egg preparation, the capillaries were found in the mesoderm layer of the CAM and not in or superficial to the ectoderm as is the case in the CAM of the intact egg which adheres to the shell membrane.

No abstract

Autologous fat grafting as a technique to correct soft-tissue defects is a controversial subject. The high percentage of fat resorption and the resulting need for additional grafting considerably reduce the value of this method. The purpose of this study was to evaluate the clinical application of tissue-culturing methodology in the handling of the lipocyte aspirate in an endeavor to improve the survival rate and therefore the take of the grafted lipocytes. The method consists of syringe aspiration of the lipocytes from the donor site, isolation of intact lipocytes by gentle centrifugation, suspension of the aspirate in an enriched cell culture medium, and injection of the cell suspension into preformed subdermal tunnels. A number of media were tested and shown to prolong the survival of lipocytes ex vivo using fluorescent acridine orange stain. Implementing the integrated cell culture techniques increased the lipocytes' viability, as indicated in clinical evaluation in which the amount of graft take ranged between 50 and 90 percent. The results of 15 patients with varied types of cases who were operated on using this new methodology show that the tissue defect was filled and remained so in postoperative follow-ups of 6 to 24 months. A three-dimensional CAT scan-aided evaluation method was developed and used in one of four case histories presented herein.