A Transposition Flap Reconstruction after Resection of a Soft-Tissue Sarcoma in the Buttock

Introduction: Large defects following resection in the gluteal region are challenging. Of note, there are a limited number of fairly morbid options for reconstruction. Case Report: A 65-year-old female presented with complaints of an enlarging mass in the left buttock over the past several months. A high-grade sarcoma was diagnosed based on a biopsy. The final diagnosis was an undifferentiated pleomorphic sarcoma based on the resected tumor. An 11-cm tumor with surrounding tissues, including the great gluteal muscle, was resected, which resulted in a 17-cm full thickness defect. The defect was reconstructed with a transposition flap elevated from the lateral thorax. A transposition flap can cover large buttock defects without sacrificing other muscles. Conclusion: Moreover, a transposition flap is esthetically acceptable because most of the operative scar is within the buttock area. A transposition flap reconstruction is one of the several options for large defects after soft-tissue sarcoma resection in the buttock

Thoracoabdominal flap reconstruction after resection of superficial soft-tissue sarcomas in the chest wall

The thoracoabdominal flap is a rotation flap, and is well known for reconstruction of defects following resections for breast cancer, but the flap is not well known for reconstructing defects following resections of soft-tissue sarcomas involving the chest wall. Here we present two patients with superficial chest wall sarcomas consisting of a dermatofibrosarcoma protuberans in a 42-year-old man and a recurrent myxofibrosarcoma in a 76-year-old man. The tumors were resected with the surrounding tissue. The defect was reconstructed with a thoracoabdominal flap elevated from the ipsilateral thorax (medially-based flap). Neither case developed necrosis of the flap or reduced shoulder range of motion. The chest wall presents few options for a donor vessel. The thoracoabdominal flap has an axial blood supply and does not require a microsurgical procedure. A thoracoabdominal flap is a suitable reconstruction option for a defect after the resection of a superficial soft-tissue sarcoma in the chest wall

Sensitivity studies of the neutronic design of a fission converter-based ephithermal beam for boron neutron capture therapy

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1997.Includes bibliographical references.by Shuichi Sakamoto.M.S

Embedding Distance Information in Binaural Renderings of Far Field Recordings

Traditional representations of sound fields based on spherical harmonics expansions do not include the sound source distance information. As multipole expansions can accurately encode the distance of a sound source, they can be used for accurate sound field reproduction. The binaural reproduction of multipole encodings, though, requires head-related transfer functions (HRTFs) with distance information. However, the inclusion of distance information on available data sets of HRTFs, using acoustic propagators, requires demanding regularization techniques. We alternatively propose a method to embed distance information in the spherical harmonics encodings of compact microphone array recordings. We call this method the Distance Editing Binaural Ambisonics (DEBA). DEBA is applied to the synthesis of binaural signals of arbitrary distances using only far-field HRTFs. We evaluated DEBA by synthesizing HRTFs for nearby sources from various samplings of far-field ones. Comparisons with numerically calculated HRTFs yielded mean spectral distortion values below 6 dB, and mean normalized spherical correlation values above 0.97

Preserving the posterior cortex of the sternum during resection of a superficial anterior chest wall sarcoma

Following resection of a sternal tumor, respiratory dysfunction can occur and rigid reconstruction is necessary. An 82-year-old woman noted a mass in the anterior chest wall that was increasing in size. The tumor was located on the left aspect of the sternum at the level of the third rib. A radiation-induced malignant spindle cell tumor was diagnosed because of a history of irradiation for hilar lymph node carcinoma. The tumor was resected with the surrounding tissues of the second-to-fourth ribs and sternum. The posterior sternal cortex was preserved by cutting with a curved chisel under fluoroscopy. The chest wall defect was reconstructed with a 2-mm thick Gore-Tex® sheet and a local transpositional flap. Sternal resection with a chisel under fluoroscopy avoids damage to the internal thoracic artery. Preserving the posterior sternal cortex does not require rigid reconstruction. The procedure is minimally invasive

Multifidus muscle retracted and preserved in resection of malignant bone tumor in the sacral ala

Resection of malignant tumors in the posterior pelvis requires multidirectional approaches for the resection and the subsequent spine-pelvic fixation. The multifidus muscle can be scarified during the operation. This is a case report of a 44-year-old male with a secondary chondrosarcoma arising from an osteochondroma in the sacral ala. Recurrence occurred 11 months after the initial operation, and the resected tissue from the recurrence was diagnosed as a chondrosarcoma. In both operations, the multifidus muscle was elevated from its distal attachment to provide an adequate view of the tumor resection and insertion of spine-pelvic instrumentation. An adequate view by elevation of the multifidus muscle is useful for a safe operation. A preserved multifidus muscle covering the instrumentation may reduce the risk of infection. The elevation and preservation of the multifidus muscle is an easy and simple method that contributes to successful resection of a malignant tumor of the pelvis

Efficacy of gelatin gel sheets in sustaining the release of basic fibroblast growth factor for murine skin defects

Background: Gelatin has been used as a material sustaining the release of basic fibroblast growth factor (bFGF), which promotes fibroblast proliferation and capillary formation and accelerates wound healing. In the application of these materials, bFGF is impregnated immediately before application, and it is difficult to conform the shape to the wound. In this study, we prepared a pliable and plastic gelatin gel sheet (GGS) that sustains bFGF and conforms to the shape of the wound as a result of cross-linking just before application. In addition, we examined the sustained release profile of bFGF from GGS and its effect on wound healing in murine skin defects. Materials and methods: A 13-wt% gelatin solution was mixed with bFGF before cross-linking with 1% glutaraldehyde solution. GGSs impregnated with 7 μg/cm2 of bFGF were incubated in phosphate-buffered saline and collagenase solution, and GGS degradation and bFGF release were evaluated. In the murine experiments, GGSs treated without bFGF and GGSs impregnated with 1, 3.5, 7, or 14 μg/cm2 of bFGF were applied to full-thickness skin defects created on the backs of C57BL/6JJcl mice, and the wound closure, epithelial length, extent of granulation tissue and capillary formation were compared. Results: bFGF was released according to the degradation of GGS in phosphate-buffered saline, and the remaining bFGF was released in collagenase solution. In the animal studies, epithelialization was accelerated in the GGSs treated with 1 and 3.5 μg/cm2 of bFGF, and granulation tissue formation and angiogenesis were promoted based on the amount of bFGF impregnated into the GGS. Conclusions: GGS impregnated with bFGF is capable of sustaining the release of bFGF, with consequent accelerated epithelialization, granulation tissue formation, and angiogenesis in vivo. GGS is a novel and promising wound dressing that sustains bFGF and can be adapted to the shape of various wounds in the treatment of both acute and chronic wounds

Perceived Self Motion in Virtual Acoustic Space Facilitated by Passive Whole-Body Movement

Presented at the 14th International Conference on Auditory Display (ICAD2008) on June 24-27, 2008 in Paris, France.When moving sound sources are displayed for a listener in a manner that is consistent with the motion of a listener through an environment populated by stationary sound sources, listeners may perceive that the sources are moving relative to a fixed listening position, rather than experiencing their own self motion (i.e., a change in their listening position). Here, the likelihood of auditory cues producing such self motion (aka auditory-induced vection) can be greatly facilitated by coordinated passive movement of a listener's whole body, which can be achieved when listeners are positioned upon a multi-axis motion platform that is controlled in synchrony with a spatial auditory display. In this study, the temporal synchrony between passive whole-body motion and auditory spatial information was investigated via a multimodal time-order judgment task. For the spatial trajectories taken by sound sources presented here, the observed interaction between passive whole-body motion and sound source motion clearly depended upon the peak velocity reached by the moving sound sources. The results suggest that sensory integration of auditory motion cues with whole-body movement cues can occur over an increasing range of intermodal delays as virtual sound sources are moved increasingly slowly through the space near a listener's position. Furthermore, for the coordinated motion presented in the current study, asynchrony was relatively easy for listeners to tolerate when the peak in whole-body motion occurred earlier in time than the peak in virtual sound source velocity, but quickly grew to be intolerable when the peak in whole-body motion occurred after sound sources reached their peak velocities

Cultured Human Epidermis Combined With Meshed Skin Autografts Accelerates Epithelialization and Granulation Tissue Formation in a Rat Model

INTRODUCTION: As the take rate of cultured epidermal autografts in burn wound treatment is variable, widely expanded meshed auto skin grafts are often used in combination with cultured epidermal autograft to increase the take rate and achieve definitive wound coverage. However, a long time (3–4 weeks) required to prepare a cultured epidermis sheet is a disadvantage. Allogeneic cultured epidermis can be prepared in advance and cryopreserved to be used in combination with auto meshed skin grafts for treating third-degree burns. Nevertheless, the human cultured epidermis (hCE) has not been proved to accelerate wound healing after meshed skin grafting. Here, we investigated the effect of hCE on wound healing in a rat model of meshed skin grafting. MATERIALS AND METHODS: Human cultured epidermis was prepared from human neonatal foreskin and assessed by the release of growth factors into the culture medium using enzyme-linked immunosorbent assay. Skin wounds were inflicted on male F344 rats and treated by the application of widely meshed (6:1 ratio) autogenous skin grafts with or without hCE (n = 8 rats per group). Wound area, neoepithelium length, granulation tissue formation, and neovascularization were evaluated on day 7 postgrafting. RESULTS: Human cultured epidermis secreted IL-1α, Basic fibroblast growth factor, platelet-derived growth factor-AA, TGF-α, TGF-β1, and vascular endothelial growth factor in vitro. In rats, hCE accelerated wound closure (P = 0.003), neoepithelium growth (P = 0.019), and granulation tissue formation (P = 0.043), and increased the number of capillaries (P = 0.0003) and gross neovascularization area (P = 0.008) compared with the control group. CONCLUSIONS: The application of hCE with meshed grafts promoted wound closure, possibly via secretion of growth factors critical for cell proliferation and migration, suggesting that hCE can enhance the healing effect of widely expanded skin autografts.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal