The efficacy of negative pressure wound therapy on chemotherapeutic extravasation ulcers: An experimental study.

CONTEXT: The extravasation of the chemotherapeutic agents is not an unusual phenomenon. Necrosis of the skin and underlying structures has been reported, depending on the cytotoxicity of the extravasating drug. Despite the presence of some antidotes, such wounds tend to enlarge with time and are likely to resist the treatment. AIMS: The objective of this study was to investigate the efficacy of negative pressure wound therapy (NPWT) on extravasation ulcers. SETTINGS AND DESIGN: Animals were separated into two groups; conventional dressing group and NPWT group. MATERIALS AND METHODS: Extravasation necrosis was established by intradermal doxorubicin injection. Following the debridement of the necrotic areas, one group of animals was treated with the conventional dressing while NPWT was applied to the other group. The wound areas were measured, and then biopsies were taken on the 3(rd), 7(th) and 14(th) days after the debridement. STATISTICAL ANALYSIS USED: SPSS 11.5 for Windows was used. Two-way ANOVA test was used to compare wound areas between groups. Willcoxon sign test with Bonferroni correction was used to compare histological scores between groups. Chi-square test with Bonferroni correction was used to compare histological scores within the group between the days. RESULTS: There is no significant difference in terms of inflammatory cell count, neovascularisation, granulation tissue formation between the groups. Contrary to these results wound areas at the end of the treatment were smaller in the NPWT group compared with the dressing group. CONCLUSION: There is the superiority of NPWT over conventional dressing in chemotherapeutic extravasation wounds as well as the wound area is concerned, but it is not proven histologically.

Soft-tissue management with immediate free flap transfer in segmental prosthetic replacement of proximal tibia sarcomas.

Knee reconstruction with endoprosthesis after tumor resection is accepted as superior when compared with the other methods. But sometimes soft tissue reconstruction would be a challenging problem in this way of treatment. Five patients who were operated for tumor resection in this location, followed by reconstruction were presented with their one-year post operative results. Four latissimus dorsi and one rectus abdominis myocutaneous free flaps were used in these patients in order to manage soft tissue problems. All patients underwent chemotherapy in postoperative period. All flaps were successful in one year post operative examination. In this report we would like to stress the importance of surgical planning and soft tissue reconstruction of a specific patient population. We think that large musculocutaneous flaps such as latissimus dorsi and rectus abdominis musculocutaneous flaps should be preferred in soft tissue reconstruction of knee region after tumor resection followed by prosthetic replacement. Additionally, this way of treatment is superior when compared to the other methods in order to prevent complications such as prosthesis exposure or infection.

Free groin flap applications in the pediatric population.

The popularity of the groin flap has gradually decreased because of the disadvantages related to its short pedicle and technically demanding harvesting. We have summarized our experience with free groin flap applications in the pediatric population, which were performed by the same surgeon between 2004 and 2007. A total of 10 free groin flap transfers were performed in patients aged 3 to 13 years. Nine of the patients were operated on because of contractures of the extremities (six lower, three upper), and one patient was operated on for facial contour augmentation. The total duration of the operation was estimated to be between 2.6 and 6.1 hours (mean: 4.1 hours). A revision of the anastomosis was performed in two patients (20%), and in one of these patients (50%) partial flap failure was seen. Flap defatting via liposuction was performed in four patients (40%) in the late postoperative period. In our opinion, donor site morbidity comes into prominence particularly in the pediatric population, and we think that free groin flap should be the first choice of free flap for suitable cases in this group of patients.

A comparison of various vascularization-perfusion venous nerve grafts with conventional nerve grafts in rats.

Peripheral nerves with defective segments can only be repaired using nerve grafts. Among the various nerve graft options, the outcome of vascularized grafts has been shown to be better, especially when used in the hypovascular and scarred recipient bed. The purpose of this study was to compare the regeneration capacities of various types of venous nerve grafts in a rat model. Forty adult male Wistar albino rats were divided into four groups. A 2-cm-long segment of femoral sheath was isolated from the surrounding tissue without disturbing the unity of the femoral sheath contents. Four different nerve graft models were applied: flow-through venous, arterialized venous, prefabricated venous, and conventional nerve graft (control). All nerve grafts were closed with silicone sheets. These neurovascular segments were reopened in postoperative week 10 to determine the viability of the grafted nerves and to assess the degree of nerve healing. Histopathologic examinations, morphometric analysis, and electrophysiological measurements were performed. The degree of nerve healing in the flow-through venous nerve grafts was similar to that observed in the arterialized nerve grafts. Prefabricated flow-through venous grafts were not as successful as flow-through venous grafts or arterialized nerve grafts. All of the vascularized nerve grafts showed better results than the conventional nerve grafts.

A modification of the neural-island flap: 'split neural-island flap'.

The purpose of this study was to demonstrate the new concept of a consistent and reliable skin-flap design supplied solely by the intrinsic vasculature of a split cutaneous nerve. A total of 88 Wistar rats were used in this experiment, which was divided into three parts. In Part I (n=20), the vascular anatomy and the fascicular anatomy of the lateral femoral cutaneous nerve were established. In Part II (n=44), split neural-island flaps were created. Two skin flaps (measuring 2x3 cm each) were harvested based solely on the lateral femoral cutaneous nerve, which was split into two based on its fascicles. In Part III (n=24), a surgical delay procedure was applied in order to augment the survival areas of split neural-island flaps. On postoperative day 7, the viability of all flaps was evaluated. The results of the anatomic studies demonstrated that the lateral femoral cutaneous nerve consisted of usually two (80%), rarely three, fascicles (20%). Meticulous dissection enabled us to separate these fascicles without disrupting the perineural vasculature around each fascicle. The mean flap survival rate in the acutely elevated split neural-island flap group in Part II was 6.2+/-3.1%, whereas survival in the graft group was 0.0%. Results of Part III of the experiment demonstrated a significantly higher survival rate for the delayed split neural-island flap (98.5+/-2.8%) compared to the acutely elevated split neural-island flap (P<0.05). In conclusion, this is a reliable skin flap that can be nourished solely by the intrinsic vasculature of an interfascicularly dissected ('split') nerve.

Interpositional vein graft suturing over temporary silastic tube.

Interpositional vein grafting is the gold standard for the replacement of vascular defects. Although many microsurgeons have used classical suture anastomosis successfully, it is still technically challenging, especially for the inexperienced surgeon. We present a new technique that facilitates autogenous vein grafting by using a commercially available silastic tube employed temporarily during the suture anastomosis and removed at the end of the procedure. Effects of this technique on operative time and patency were tested by an experienced and an inexperienced microsurgeon. Each surgeon operated on a total of 20 rats divided in experimental and control groups of 10 animals each. The experimental group was operated on with silastic-tube-assisted suture anastomosis, and the control group was operated on using the classical suture anastomosis without using the device. For the experienced microsurgeon, proposed modification resulted in a statistically significant reduction in operative time without an effect on patency. For the inexperienced microsurgeon, the proposed modification resulted in a statistically significant reduction in operative time and also enhanced patency rates significantly. Interpositional vein grafting over a temporary silastic tube is a practical modification of the classical microvascular anastomosis that adds speed and ease to the microvascular vein grafting procedure and prevents back-wall biting, particularly for inexperienced microsurgeons.

Gluteus maximus neural-island flap model in the rat.

Flaps that are supplied solely by intrinsic vasculatures of the nerves have been introduced; however, clinical applications of the muscle flaps have not been performed. Our aim in this study was to develop a neural-island muscle flap model. The study was composed of anatomic investigations (part I, n = 8), creation of the neural-island muscle flap model (part II, n = 40), and augmentation of the flap (part III, n = 20). After part I, we concluded that the gluteus maximus would be the most effective muscle for our model. In part II, gluteus maximus muscles were isolated on their motor nerves in 20 rats and, in the remaining 20, were harvested as grafts. A delay procedure was applied in part III.Average viability percentages of the graft group, acutely elevated group, and delayed group were 0.0% +/- 0.0%, 25.1% +/- 6.4% and 96.1% +/- 7.8%, respectively. This study provides a reliable muscle flap model that can be created as pedicled by the intrinsic vasculature of its motor nerve.

An unusual variation of deltoid muscle.

An unusual anatomic variation of the deltoid muscle was found in a 45-year-old female cadaver during dissection of the right upper extremity. The posterior fibers of the right deltoid muscle were enclosed in a distinct fascial sheet and the deltoid muscle was seen to arise from the middle 1/3 of the medial border of the scapula. There was no accompanying vascular or neural anomaly of the deltoid muscle. To the best of our knowledge, unilateral posterior separation of the deltoid muscle with a distinct fascia has not been described previously. While dissecting deltoid, posterior deltoid, or scapular flaps, the surgeon needs to look out for this variation because it may cause confusion.

Motor reinnervation of a denervated muscle by using a sensory nerve: an experimental study on gluteus maximus muscle of the rat.

PURPOSE: This study aimed at developing a new muscle reinnervation technique using a sensory nerve. METHODS: We attempted innervation of the rat gluteus maximus muscle using the lateral femoral cutaneous nerve (LFCN). We placed the gluteus maximus muscle into the fibroadipose tissue in the distribution of the LFCN in 24 rats. In one group, the original innervation remained intact. In the second and third groups, the muscles were denervated, and in the third group, the proximal end of the nerve to the gluteus maximus was sutured to the distal end of the divided LFCN. We compared muscle reinnervations of the groups by using electrophysiologic evaluation of the muscle contractions, light microscope evaluation of the axonal regenerations, and scanning electron microscope evaluation of the actin-myosin structures of the muscles at the end of an elapsed waiting period. RESULTS: At the end of electrophysiologic evaluation, the mean area of compound muscle action potentials measured in group 1 was 3.8 ms/mV; in group 2, 0.0; and in group 3 (experimental group), 0.5. Axonal regeneration was observed distal to the coaptation, and actin-myosin structures were mostly spared in group 3. CONCLUSIONS: This study explored the feasibility of a new flap prefabrication method that aims at developing reinnervation of a denervated muscle by means of a sensory nerve. In light of histologic and electrophysiologic findings, this type of reinnervation is possible.

Neuromuscular and neuromusculocutaneous flaps in the rat.

Since the introduction of flaps based on the vascular structures of the cutaneous nerves, these have gained increasing popularity in reconstructive surgery. The purpose of this study is to describe a new concept in which the flap is supplied solely by the intrinsic vasculature of a motor nerve. A total of 94 Wistar rats weighing 200-250 g were used in this experiment, which was divided into three sections. In section I, the neural anatomy of the posterior thigh region was investigated. In section II, the flap study using experimental and control groups, was performed. In the experimental group neuromuscular and neuromusculocutaneous flaps were created. The biceps femoris muscle was harvested based solely on its motor nerve as a neuromuscular flap, and together with its overlying skin it was similarly raised as a neuromusculocutaneous flap. In the control group, conventional muscle and musculocutaneous flaps were harvested based on the caudal femoral-popliteal artery vascular axis, and a graft subgroup was created ligating both the constant vascular structure and the motor nerve. In section III, with the intention of augmenting the survival areas of neuromuscular and neuroumusculocutaneous flaps, a surgical delay procedure was applied. On postoperative day 7, the viability of all flaps was evaluated using direct observation, microangiography, and tetrazolium blue stain techniques. The results of the anatomic studies demonstrated a consistent motor nerve arising from the sciatic nerve to the biceps femoris muscle with evident perineural vasculature. Average muscle viability levels of neuromuscular, neuromusculocutaneous, delayed neuromuscular, delayed neuromusculocutaneous, conventional muscle and musculocutaneous flaps were 20.6 +/-7.58, 22.4 +/- 4.21, 86.4 +/- 6.14, 85 +/- 4.21, 89.6 +/- 4.48, and 88.0 +/- 5.51%, respectively. Survival levels of the skin paddles of the neuromusculocutaneous, delayed neuromusculocutaneous, and conventional musculocutaneous flaps were calculated as 13 +/- 17.51, 67 +/- 30.29, and 97+/-4.21%, respectively. In the graft subgroup the viability of muscle and skin paddle was almost nil. In conclusion, our new flap model in a favored laboratory animal is of benefit to researchers in providing a means for future various types of investigations into this new concept. The technique might be considered in further experimental research studies and appropriate clinical situations.

A new epineural nerve repair technique with external metallic circle.

BACKGROUND: Despite the existence of various nerve coaptation techniques, functional results of nerve repair are still inadequate. Potential benefits of developing modified coaptation techniques cannot be disregarded. METHODS: The authors report a new coaptation technique in which the epineural sutures were performed with an external metallic circle to increase the coaptation surface. The sciatic nerves of 30 male Wistar albino rats were used in the study. RESULTS: The mean Sciatic Function Index values in external metallic circle repair (n:11) and conventional epineural repair (n:10) groups were -42.35 +/- 22.95 and -69.34 +/- 17.96, respectively (p = 0.020). Electrophysiological studies revealed that the duration of compound muscle action potentials (CMAP) was (p = 0,012) shorter in conventional nerve repair group than it was in external metallic nerve repair. When external metallic circle repair and conventional epineural repair groups were examined for distal nerve segments, there were significant findings for the diameter of axons (p = 0.005), diameter of nerves (p = 0.000), and for G ratios (p = 0.000). The mean intraepineural cross sectional areas of external metallic circle repair and conventional epineural repair groups were 3.57 +/- 0.21 and 2.92 +/- 0.23 mm(2), respectively (p = 0.000). CONCLUSION: The external metallic circle repair technique enhances nerve regeneration by enabling a larger sprouting and contact area for nerve fibers.

A new flap design: neural-island flap.

This report introduces the "neural-island flap" concept, which represents a consistent and reliable skin flap design supplied only by the intrinsic vasculature of a cutaneous nerve. In this study, the lateral femoral cutaneous nerve was selected as the pedicle of the neural-island flap, and a standard skin flap, which is the territory of the accompanying vessels (i.e., iliac branches of the iliolumbar artery and vein), was elevated on the lower dorsal region of the rats. In a total of 92 Wistar rats, three experiments were performed. In part I (n = 24), the vascular anatomy of the lateral femoral cutaneous nerve was established by the methods of dissection, microangiography, nerve mapping, perfusion with colored latex and India ink, and histologic analysis. In part II (n = 46), the role of the cutaneous nerve in supporting an acutely elevated skin flap was explored by creating five flap groups as follows: group 1, conventional flap (artery, vein, and nerve intact); group 2, neural island flap (only the nerve intact); group 3, neurocutaneous flap (vein and nerve intact); group 4, denervated flap (artery and vein intact); and group 5, skin graft. In part III (n = 22), the role of a preliminary surgical delay procedure to augment the survival of the neural island flap was investigated. Results of the anatomic studies indicated a consistent perineural vasculature by the accompanying iliolumbar artery. Skin flaps survived totally in groups where the artery and vein were intact, whereas mean survival rates for the neural island flap and the neurocutaneous flap were 38.2 +/- 3.1 percent and 44.5 +/- 3.8 percent, respectively (p > 0.05). Results of part III of the experiment demonstrated a significantly higher survival for the delayed neural island flap (94.5 +/- 5.5 percent) compared with the acutely elevated neural island flap (p < 0.05). The perineural and intraneural vessels were found to be greatly dilated after a delay procedure, demonstrated by direct observation, microangiography, histologic analysis, dye injection study, and scanning electron microscopy. On the basis of this promising series of experiments, a clinical technique was developed using the sural neural-island flap. The flap was used to reconstruct lower extremity defects in four cases. A delay procedure was accomplished in the first stage by elevating a fasciocutaneous flap from the midcalf region based on a posterior skin bridge and the sural nerve. After a 2-week delay period, a sural neural-island flap was created based on the nerve and transposed to the defect. Flap survival was complete in all cases, with a satisfactory result. The authors conclude that this report proves for the first time that a robust and reliable skin flap can be created pedicled only by the intrinsic vasculature of a cutaneous nerve, after a proper surgical delay. The so-created neural-island flap design offers two novel advantages: (1) a very narrow pedicle and (2) a pedicle without any restriction to a specific pivot point, in addition to the previously described unique advantages of preservation of a major artery and avoidance of microvascular anastomoses.

Microsurgical revascularization of almost totally amputated alar wing of the nose.

A case of nearly complete amputation of the alar wing is presented whereby a successful arterial revascularization was accomplished using an arterial rerouting technique. Venous stasis was overcome by means of stab-wound wiping. An excellent result was obtained following complete survival of the revascularized segment. The authors conclude that microvascular revascularization should always be attempted whenever possible, even if a skin bridge is preserved in nearly complete amputations of the nose.

Oblique radial forearm reverse-flow flap.

A modifed design for the distally-based radial forearm flap is presented, in an oblique direction rather than longitudinally, based on the existence of skin laxity in the proximal forearm region. The skin paddle of the flap is designed in an oblique fashion pedicled on one of the proximal-row septocutaneous perforators, and elevated in the usual manner supplied by the distal radial artery. The oblique radial forearm flap thus created was successfully utilized for reconstruction of seven dorsal hand defects. Results showed that all the flaps could easily be transposed to the defect through a wide arc of rotation and all survived totally, with direct closure of the donor site in five cases, and significant reduction in size in the remaining two cases. It was concluded that the oblique design for the skin island of the reverse radial forearm flap could allow creation of a flap that has a smaller donor defect and yet presents a longer pedicle length, with a wider arc of rotation and better adaptation to a dorsal hand defect, than a conventional longitudinal-design radial forearm flap.

Easy method of capturing microscopical images by using a consumer-type digital camera.

Taking pictures of microstructures is difficult, requiring sophisticated cameras coupled by the microscopes. Furthermore, it may not be feasible to find an operating microscope paired with a camera, especially in laboratory conditions. Considering the difficulty of obtaining microscopic photographs in clinical and laboratory settings, this report describes a practical method of digital photography of microstructures using a consumer-type digital camera. The technique can be summarized simply as placing the lens of a consumer-type digital camera over the eyepieces of a surgical microscope, whereby the anatomic structure of interest is focused. The image thus obtained is transferred to the computer, using easily available software programs. The authors conclude that this method is an inexpensive and practical way of capturing photographs of microstructures, obviating the need for using microscopes coupled by the cameras.