マイクロコンピュータ断層撮影とヌードマウスへのヒト脂肪注入の生存率の評価
Summary
Fat grafting is an essential technique for reconstructing soft tissue deficits. However, it remains an unpredictable procedure characterized by variable graft survival. Our goal was to devise a mouse model that utilizes a novel imaging method to compare volume retention between differing techniques of fat graft preparation and delivery.
Abstract
Lipotransferは体全体の軟部組織欠損の治療のために外科医の装備一式に不可欠なツールです。脂肪はそれは、容易に入手容易に得られる、安価で、かつ本質的に生体適合性であるように、理想的な軟部組織充填剤である。1しかし、その急成長の人気にもかかわらず、脂肪グラフト化は10からどこでも及ぶ公開さ保持率で、予測できない結果と可変移植片の生存によって妨げられる-80％。1-3
脂肪移植に関する研究を促進するために、我々は、従って、注入された脂肪の体積保持のリアルタイム分析を可能にする動物モデルを開発した。簡単に言えば、小さなカットCD-1ヌードマウスの頭皮で行われ、処理脂肪吸引物200-400μlの頭蓋骨上に配置される。頭皮が原因のエイズ頭蓋冠が提供する優れた背景のコントラストのためにネイティブ皮下脂肪のその不在の受信者サイトとして選ばれた、とされている分析プロセス。マイクロコンピュータ断層撮影（マイクロCT）は、ベースライン時にグラフトし、その後隔週をスキャンするために使用される。 CT画像が再構成され、画像化ソフトウェアは、グラフト量を定量するために使用される。
伝統的に、この技術は、ex vivoでの物理的な測定によってグラフト重量および体積の単一の評価を提供するために、試験動物を安楽死必要としている脂肪移植体積を評価した。生化学的および組織学的な比較は、同様に、安楽死させるための研究の動物を必要とした。これは、イメージング技術を可視化し、客観試験動物を犠牲にすることなく、初期の移植後の複数の時点でのボリュームを定量化するという利点を提供する。技術は、より大きな移植片リスク皮膚および脂肪壊死として注入することができる移植片の大きさによって制限される。この方法は、脂肪移植の生存率および体積保持を評価するすべての研究のための有用性を有する。これは、特にprovidiによく適しています脂肪移植片の視覚的な表現をngのと時間をかけて音量の変化を次のよう。
Introduction
Soft tissue defects arise from a variety of causes including trauma, tumor resection, aging, and congenital anomaly. They can be debilitating for patients, and represent one of the most common, yet challenging problems for reconstructive surgeons. Many methods exist for addressing soft tissue deficiencies, such as local and free flaps, collagen injections, and synthetic fillers.4-8 However, since its first documented use by Neuber in 18931, autologous fat transfer remains the gold standard for the repair of soft tissue deficits, as it is ready available, easy and safe to harvest, and naturally compatible.1,2
Despite these advantages, autologous fat grafts suffer from unpredictable and variable survival, with retention rates ranging anywhere from 10-80% over time.1-3,9 In order to account for this expected loss of volume and symmetry, surgeons must often overcorrect when filling soft tissue defects, or perform multiple follow-up procedures.
Poorly vascularized graft beds are partly to blame for this tissue resorption. Additionally, the lack of a benchmark analysis method to compare graft survival may also contribute to the inconsistency in reported results. A precise method for measuring graft volume would reduce measurement error when evaluating retention rates. This in turn would help researchers more accurately identify the causative factors that affect graft survival. Although many laboratory animal models have facilitated both quantitative and qualitative assessment of human fat graft survival, most are based on histological and biochemical means and require sacrificing the study animal to yield a single measurement.3,10-12 Little has been reported on the use of imaging techniques to enumerate fat graft volume retention in vivo.
A handful of clinical studies have shown more effective measurement techniques using imaging. Magnetic Resonance Imaging (MRI) was employed by Hörl et al. to measure fat graft survival13, and CT was utilized by Har-Shai et al. and Fontdevila et al. in their analyses of volume retention after grafting in patients who suffered from HIV.14,15 Employing three-dimensional (3D) imaging software, Meier et al. measured volume retention in humans after autologous fat grafting by comparing images from the preoperative and postoperative period.16
Yet, a standardized method employing imaging to measure fat graft survival is lacking in basic science research. A high resolution imaging approach for assessing the volumes of fat grafts would allow not only for accurate and reproducible volume measurements, but also for repeated measurements allowing visualization of the evolution of fat graft survival in a real time fashion.
Protocol
Representative Results
Discussion
この時点までは、ほとんどの研究者は脂肪移植片の長期生存を定量化するために、非イメージングモダリティに依存してきたが、これらの方法は、単一の測定試験動物及び収率の犠牲を必要とする。3,10-12我々の研究で表すマウスモデルにおける脂肪移植片生存の目的、リアルタイム定量を可能にする改良された分析方法。
このプロセスにおける重要な、これは?…
Divulgazioni
The authors have nothing to disclose.
Acknowledgements
この研究は、ACSフランクリンH·マーティン学部研究フェローシップ、HageyによってサポートされていましたMTLDCWに小児再生医療のためのHagey研究所、オーク財団によってサポートされ、国立衛生研究所、助成NIHR21DE019274、NIHR01DE019434、NIHR01DE021683、およびNIHU01HL099776た小児再生医療のための研究所、スタンフォード大学小児保健研究所学部奨学生賞。マイクロCTは、in vivoイメージングにおけるイノベーションのためのスタンフォードセンターで行われた。
Materials
| Reagents and Materials | Manufacturer |
| SAL lipoaspirate | N/A |
| Centrifuge | Beckman Coulter, Inc., Pasadena, CA |
| 50 ml conical tubes | BD Biosciences, San Jose, CA |
| CD-1 nude mice (Crl:CD1-Foxn1nu) | Charles River Laboratories, Inc., Wilmington, MA |
| Isoflurane | Henry Schein, Dublin, OH |
| 2.5% Betadine | Purdue Pharma, L.P., Stamford, CT |
| 70% Ethanol solution | Gold Shield, Hayward, CA |
| 1cc luer-lock syringe | BD Biosciences, San Jose, CA |
| 14 gauge cannula | Shippert Medical, Centennial, CO |
| Forceps | Fine Science Tools, Heidelberg, Germany |
| Tenotomy scissors | Fine Science Tools, Heidelberg, Germany |
| 6-0 nylon suture | Ethicon, Blue Ash, OH |
| Phosphate buffered saline | Gibco, Carlsbad, CA |
| micro-CT scanner | Siemens Healthcare, Pleasanton, CA |
| Phantom | TriFoil Imaging, Northridge, CA |
| Imaging analysis software | IRW, Siemens Healthcare, Pleasanton, CA |
| Scale | Mettler-Toledo International, Inc., Columbus, OH |
Riferimenti
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- Horl, H. W., Feller, A. M., Biemer, E. Technique for liposuction fat reimplantation and long-term volume evaluation by magnetic resonance imaging. Ann Plast Surg. 26 (3), 248-258 (1991).
- Har-Shai, Y., Lindenbaum, E. S., Gamliel-Lazarovich, A., Beach, D., Hirshowitz, B. An integrated approach for increasing the survival of autologous fat grafts in the treatment of contour defects. Plast Reconstr Surg. 104 (4), 945-954 (1999).
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- Matsumoto, D., et al. Cell-assisted lipotransfer: supportive use of human adipose-derived cells for soft tissue augmentation with lipoinjection. Tissue Eng. 12 (12), 3375-3382 (2006).
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