Robert E. H. Ferguson

Autologous fat grafts harvested and refined by the Coleman technique: a comparative study.

Background: The viability of fat grafts obtained by even a well-established technique remains poorly studied and unknown. This study was designed to determine the viability of fat grafts harvested and refined by the Coleman technique. Methods: Sixteen adult white women were enrolled in this study. In group 1 (n = 8), fat grafts were harvested and processed with the Coleman technique by a single surgeon from the abdomen of each patient according to his standardized method. In group 2 (n = 8), fat grafts were harvested with the conventional liposuction by another surgeon. After centrifugation, the resulting middle layer of tissue was collected. All fat graft samples were analyzed for the following studies: trypan blue vital staining for viable adipocyte counts, glycerol-3-phophatase dehydrogenase assay, and routine histologic examination. Results: The higher viable adipocyte counts were found in group 1 compared with group 2 (4.11 ± 1.11 versus 2.57 ± 0.56 × 106 cells/ml; p < 0.004). The level of glycerol-3-phophatase dehydrogenase activity was significantly higher in group 1 compared with group 2 (0.66 ± 0.09 versus 0.34 ± 0.13 U/ml; p < 0.0001). Histologic examination showed normal structure of fragmented fatty tissues in both groups. Conclusions: Although fat grafts obtained by both methods maintain normal histologic structure, the Coleman technique yields a greater number of viable adipocytes and sustains a more optimal level of cellular function within fat grafts and should be considered superior to conventional liposuction as a preferred method of choice for fat graft harvesting.

The Viability of Autologous Fat Grafts Harvested With the LipiVage System : A Comparative Study

This study evaluates the viability of adipose aspirates harvested with the LipiVage system (Genesis Biosystems Inc, Lewisville, TX), a newly developed fat harvesting device, and determines a potentially preferred method for possible large-quantity fat graft harvesting. Adipose aspirates were harvested with the LipiVage system from the abdomen of 16 female patients (group 1, n = 8) according to the instruction by the manufacturer and with conventional liposuction (group 2, n = 8). Samples from conventional liposuction were spun at 50 g for 10 minutes and the resulting middle layer of fat was collected. All fat graft samples were evaluated with trypan blue vital staining for viable adipocyte count, glycerol-3-phosphatase dehydrogenase (G3PDH) assay for intracellular enzyme activity, and histology. In this study, group 1 had significantly higher viable adipocyte count than group 2 had (3.7 ± 0.64 versus 2.37 ± 0.56 × 106 /mL, P = 0.0021). G3PDH assay showed a marked increase of intracellular enzyme activity in group 1 compared with in group 2 (0.61 ± 0.10 versus 0.34 ± 0.13 U/mL, P = 0.00045). Histology revealed normal structures of fragmental fatty tissues in both groups. While adipose aspirates by both modalities maintain normal structure, the LipiVage system yields a greater number of viable adipocytes and sustains a higher level of intracellular enzyme activity within fat grafts and can potentially be a preferred method of choice for large-quantity fat graft harvesting.

The use of a hydrogel sealant on flexor tendon repairs to prevent adhesion formation

The prevention of peritendinous adhesions after zone II flexor tendon repair poses a significant challenge to hand surgeons. This study evaluates a hydrogel sealant (FocalSeal-L) as a barrier to peritendinous adhesion formation. The deep flexors of toes 2 through 4 were divided and repaired in 30 chickens. Chickens were randomized to tendon repair with (n = 15) or without (n = 15) FocalSeal-L. Each group was further randomized to have their tendons studied postoperatively at 3 (n = 10), 6 (n = 10), or 12 (n = 10) weeks. Histologic evaluation revealed decreased peritendinous adhesion formation in the FocalSeal-L group. Biomechanical analysis demonstrated a decrease in work of flexion in the FocalSeal-L group that was most pronounced at 6 weeks (P = 0.0020). There was no significant difference in breaking strength. Apparently, an effective barrier to peritendinous adhesion formation, this sealant system is easy to use, biocompatible, and bioresorbable. In addition, it is not bulky or restrictive to tendon glide.

Cryopreservation of autologous fat grafts harvested with the Coleman technique.

The viability of fat grafts harvested with an established technique after cryopreservation remains unknown. This study was conducted in vitro to evaluate the viability of autologous fat grafts harvested with the Coleman technique and subsequently preserved with our preferred cryopreservation method. Eight adult females were enrolled in this study. In each patient, 10 mL of fat grafts were harvested with the Coleman technique by a single surgeon from the lower abdomen. In group 1, 5 mL of fresh fat grafts were mixed with cryoprotective agents and underwent cryopreservation with controlled slow cooling and fast rewarming. In group 2, 5 mL of fresh fat grafts without cryopreservation from the same patient served as a control. The fat graft samples from both groups were evaluated with trypan blue vital staining, glycerol-3-phophatase dehydrogenase assay, and routine histology. Viable adipocyte counts were found similar in both group 1 and group 2 (3.46 ± 0.91 vs. 4.12 ± 1.11 × 106/mL, P = 0.22). However, glycerol-3-phophatase dehydrogenase activity was significantly lower in group 1 compared with group 2 (0.47 ± 0.09 vs. 0.66 ± 0.09 u/mL, P < 0.001). Histologically, the normal structure of fragmented fatty tissues was found primarily in both groups. Our results indicate that autologous fat grafts harvested with the Coleman technique and preserved with our preferred cryopreservation method have a normal histology with near the same number of viable adipocytes as compared with the fresh fat grafts. However, those cryopreserved fat grafts appear to have a less optimal level of adipocyte specific enzyme activity compared with the fresh ones and thus may not survive well after they are transplanted without being optimized.

The effect of saliva and oral intake on the tensile properties of sutures: an experimental study.

The plastic surgeon often operates in the oral cavity. Little or no information exists regarding the effect of saliva and oral intake upon the tensile properties of suture. Polyglactin 910 (Vicryl) and chromic gut were studied. Five sutures of each type were subjected to saline, saliva, milk, or soy milk over different durations of exposure. Suture breaking strength was tested. A 4-way interaction between suture type, size, liquid, and time was significant (P = 0.0046). Sutures soaked in saliva were significantly weaker. No significant difference was observed between sutures soaked in milk or soy. Saliva appears to enhance degradation rates in both sutures. Suture selection in the oral cavity should be predicated upon the demands of the repair and surgeons preference. Postoperative feeding instructions should limit tension across mucosal repairs, but the selection of formula should be based upon nutritional requirements and preferences of the child rather than concern over suture degradation.