Olfactory ensheathing cells seeded decellularized scaffold promotes axonal regeneration in spinal cord injury rats.

Spinal cord decellularized (DC) scaffolds can promote axonal regeneration and restore hindlimb motor function of spinal cord defect rats. However, scarring caused by damage to the astrocytes at the margin of injury can hinder axon regeneration. Olfactory ensheathing cells (OECs) integrate and migrate with astrocytes at the site of spinal cord injury, providing a bridge for axons to penetrate the scars and grow into lesion cores. The purpose of this study was to evaluate whether DC scaffolds carrying OECs could better promote axon growth. For these studies, DC scaffolds were cocultured with primary extracted and purified OECs. Immunofluorescence and electron microscopy were used for verification of cells adhere and growth on the scaffold. Scaffolds with OECs were transplanted into rat spinal cord defects to evaluate axon regeneration and functional recovery of hind limbs. Basso, Beattie, and Bresnahan (BBB) scoring was used to assess motor function recovery, and glial fibrillary acidic protein (GFAP) and NF200-stained tissue sections were used to evaluate axonal regeneration and astrological scar distribution. Our results indicated that spinal cord DC scaffolds have good histocompatibility and spatial structure, and can promote the proliferation of adherent OECs. In animal experiments, scaffolds carrying OECs have better axon regeneration promoting protein expression than the SCI model, and improve the proliferation and distribution of astrocytes at the site of injury. These results proved that the spinal cord DC scaffold with OECs can promote axon regeneration at the site of injury, providing a new basis for clinical application.

Quantitative regression analysis of the cutaneous vascular territories in a rat model.

BACKGROUND: The rat skin flap model has been widely used in experimental flap survival studies; however, most of these have been qualitative studies. The purpose of this study was to investigate the quantitative relationship between the diameter of a cutaneous artery and the area of skin that it supplies, and also to explore the factors that influence this relationship. METHODS: Thirty rats were injected with lead oxide and gelatin and then radiographed. Computer imaging of the diameter and the area of blood supply of the cutaneous artery were made to investigate the mathematical relationship between the arterial diameter and its perfusion area. Angiograms were assembled using Adobe Photoshop and analyzed with Scion Image and SPSS software. RESULTS: The blood vessels had an average diameter of 0.53 ± 0.12 mm, perimeter of 18.74 ± 4.84 cm, vascular density of 391.31 ± 76.58 gray value/pixel cm, vascular territory of 22.32 ± 10.04 cm(2) and supplying volume of 4.88 ± 3.02 cm(3). There was a positive correlation between the diameter and the perimeter of the vascular territory, and the area and volume of the vascular territory. The linear regression equation was y = 32.44x + 1.23 [y: nutrition region perimeter (cm), x: cutaneous artery diameter (mm)], y = 72.70x-15.93 [y: supplying area (cm(2)), x: cutaneous artery diameter (mm)] and y = 20.36x-5.83 [y: supplying volume (cm(3)), x: cutaneous artery diameter (mm)], respectively. CONCLUSIONS: Based on this data, it is postulated that the size of reliable skin flaps can be calculated by the diameter and the distribution patterns of the cutaneous artery. With the same diameter, the area of the flap supplied by branch-style artery is larger than the one supplied by the axial artery.

Functional total heel reconstruction with a fibular osteomyocutaneous flap.

The fibular osteocutaneous flap is a versatile option for a range of reconstructive challenges. In this report, a novel osteocutaneous fibular flap in which a V-shaped strut of fibula was used to reconstruct the weight-bearing function of the calcaneus has been described. The case raised interesting questions about the vascularity of the fibular flap, which we addressed with an anatomic study of the lower leg. Eight cadavers were injected with the modified lead oxide-gelatin mixture. Two cadavers were selected for three-dimensional reconstructive modeling. Dissections of each layer were performed to outline the course of every perforator in the lateral leg and the region of the ankle. The peroneal artery originated from 5.0 +/- 1.0 cm inferior to the lateral fibular tuberosity (diameter of 2.0 +/- 0.4 mm). The artery gave off 7.6 +/- 1.8 branches and provided blood supply to the fibula bone and its adjacent soft tissue. Proximal perforators from the peroneal artery were large and consistent. Based on the success of this clinical case and the details of the vascular anatomy, the authors feel that distally based osteocutaneous fibular flaps with a V-shaped strut of fibula offer a novel option for reconstruction of complex defects in the heel area in which there are both bony and soft tissue defects.

A mini pig model for visualization of perforator flap by using angiography and MIMICS.

BACKGROUND: Research performed using animal models has assisted in the understanding of flap anatomy and physiology. Pigs' vasculature in the skin is anatomically and physiologically similar to human, making it an ideal model for research. Until now, most vascular imaging studies are of two-dimensions. The aim of this study is to provide a three-dimensional (3D) model that reveals detailed architecture of the vascular network of the porcine, for accurate quantitative assessment. METHODS: Five Guangxi Bama minipigs were anaesthetized intramuscularly and underwent whole body lead oxide-gelatin injection. Spiral computed tomography scanning was performed on the subjects and three-dimensional reconstructions were made. Another minipig was used, and underwent Cardiografin injection. 3D-reconstruction was executed in vivo. All subjects were then dissected by layers to document the individual perforators. RESULTS: Angiography using perfusion with lead oxide-gelatine mixture has the advantage of illustrating distinctively the vessels and their perforating branches. However, it is incapable of displaying other tissues structures. Angiography through perfusion with Cardiografin in vivo has the advantage of demonstrating the relationship between arteries and bones. Yet it could only display coarsely the vascular trunk, and is incapable of displaying the vascular network. By combining these two methods, the 3D structure, source, course, and territories of the arteries were presented distinctively. CONCLUSIONS: 3D modeling in combination with traditional sectional imaging of the pig model enables blood vessels to be displayed more dynamically with greater realism. The procedure described could be useful for future flap research, by offering a better visualization of the vascular structure of the skin flap, allowing for better anatomical understanding.

Three-dimensional angiography of the superior gluteal artery and lumbar artery perforator flap.

BACKGROUND: Three-dimensional angiography was first proposed by Cornelius and advanced by Voigt in 1975. Since then, a variety of improvements have been made. The three-dimensional evaluation of perforator flaps is no longer a clinical curiosity but an absolute necessity. By combining three-dimensional digital imaging and angiography, the authors have developed a new three-dimensional technique for visualizing blood vessels. This method produces a digitized model of the lumbar artery and superior gluteal artery musculocutaneous perforators that enables secure elevation of the lumbar and superior gluteal artery cross-boundary perforator flap. METHODS: Two cadavers underwent whole body lead oxide-gelatin injection. Spiral computed tomographic scanning was then performed on the cadavers and three-dimensional reconstructions were performed. Six fresh bodies were used, and underwent latex injection. Specimens were then dissected by layers to document the individual perforators. RESULTS: An average of five superior gluteal artery musculocutaneous perforators with a diameter of 0.6 mm were present in the specimens. The average diameter and area supplied by perforators from the lumbar arteries was 0.7 mm and 30 cm, respectively. The three-dimensional reconstructed model of the lumbar region can display the modality, spatial location, and adjacent relationship of the lumbar and superior gluteal arteries. CONCLUSIONS: Three-dimensional modeling of lumbar and superior gluteal artery perforator flaps could provide greater insight into perforator anatomy in combination with traditional sectional imaging. Three-dimensional reconstructive modeling is now a clinically available process which, in the future, could provide great value in basic science investigation, clinical training, preoperative design, and virtual surgical procedures.