Arteriographic study of the rabbit lower limb

Arterial branching pattern of the rabbit femoral artery

Rabbits have highly developed hindlimb muscles, whereas their bones are fragile, thus resulting in frequent hindlimb fractures. To repair these fractures, it is important to understand the arterial branching pattern of the femoral artery, as it provides the main blood supply to the hindlimb. Since the descriptions from prior studies are insufficient, the aim of the present study was to determine the detailed arterial branching pattern of the rabbit femoral artery. Therefore, to address this issue, we examined 30 male and 20 female New Zealand White rabbits after colored latex injections into the femoral artery. Results showed that the femoral artery gave rise to the pudendoepigastric trunk, along with the deep femoral, lateral circumflex femoral, superficial caudal epigastric, saphenous, descending genicular, and proximal and middle caudal femoral arteries, in conjunction with frequent individual variations. In all the observed halves, the last branch from the femoral artery was the distal caudal femoral artery. Individual variations in the branching pattern of these arteries occurred independently in the proximal and the distal portions of the femoral artery, and they were, respectively, categorized into four and three major types based on the number of the branching levels along the proximodistal axis of the femoral artery. The individual variations in the arterial branching pattern of the rabbit femoral artery that were demonstrated in the present study may provide an important anatomical basis for refining the orthopedic surgical procedure in the rabbit.

Anatomical variations in the aortic bifurcation in new zealand white rabbits on arteriography

The radiologic anatomy of the aortic bifurcation in the rabbit has received little study but it is important as this anatomical area is widely used in atherosclerosis research. Thirty rabbits were used to study the aortic bifurcation and subsequent branching patterns on arteriography. Fifteen different arteries were identified. Mean arterial diameters of 2.88 ± 0.7 and 2.27 ± 0.55 mm were obtained for the aorta and external iliac arteries, respectively. The cranial and middle aspects at the seventh lumbar vertebra (L7) were the most frequent anatomical landmarks (53.3% of the cases) for aortic and common iliac bifurcations, respectively. The caudal aspect of L6 was the most frequent origin (50% of the cases) for the median sacral artery. Deep circumflex iliac arteries originated from common iliac arteries and not the abdominal aorta in the rabbit, showing anatomical asymmetry in 73.3% of the cases. No gender disparity was found in the anatomical location of any of the arteries of the study. Knowledge of normal vascular landmarks for the aortic bifurcation as well as anatomical variations should be helpful to future experimental studies.

High-contrast in vivo visualization of microvessels using novel FeCo/GC magnetic nanocrystals

FeCo-graphitic carbon shell nanocrystals are a novel MRI contrast agent with unprecedented high per-metal-atom-basis relaxivity (r(1) = 97 mM(-1) sec(-1), r(2) = 400 mM(-1) sec(-1)) and multifunctional capabilities. While the conventional gadolinium-based contrast-enhanced angiographic magnetic MRI has proven useful for diagnosis of vascular diseases, its short circulation time and relatively low sensitivity render high-resolution MRI of morphologically small vascular structures such as those involved in collateral, arteriogenic, and angiogenic vessel formation challenging. Here, by combining FeCo-graphitic carbon shell nanocrystals with high-resolution MRI technique, we demonstrate that such microvessels down to approximately 100 mum can be monitored in high contrast and noninvasively using a conventional 1.5-T clinical MRI system, achieving a diagnostic imaging standard approximating that of the more invasive X-ray angiography. Preliminary in vitro and in vivo toxicity study results also show no sign of toxicity.

A novel angiographic methodology for the quantification of angiogenesis

The objective is to develop a method to quantify the dynamic information of contrast transport using angiography for investigating angiogenic treatments. In the rabbit hindlimb ischemia model, contrast media transport was examined for both arteries and the microvasculature. Time histories of image intensity were constructed and modeled. The differences in contrast transport quantified by the parameters of the mathematical model were statistically compared between animals treated with an adenoviral vector that expressed vascular endothelial growth factor and untreated animals. The data reveal that after one week of ischemia, treated animals have a statistical increase in the number of large vessels that convect blood more efficiently. This analysis further shows a statistically significant increase in the angiographic blush in the treated animals. A methodology is described that offers the capability of examining the number and geometry of large arteries, the dynamics of contrast transport, and the amount of angiographic blush that is related to microvascular density. In therapeutic angiogenesis, numerous techniques are used to measure variables such as the angiographic score, capillary density, and regional blood flow. The analysis presented herein can offer information of these variables, and is transferable from the laboratory to the clinical arena.

New simplified radio-opaque injection technique for visualization of rat arteries

We have developed a new and simplified injection technique based on a mixture of latex and lead oxide. This injection technique is unique in its possession of both color and radio-opacity. We have developed and refined this methodology in rats, and have demonstrated it to possess superior qualities of injectability. Depiction of small vessels is highly detailed both radiographically and grossly.

Biologic model of bone transport distraction osteogenesis and vascular response

We developed an experimental model in the rabbit of distraction osteogenesis through bone transport that closely corresponds to the clinical use of bone transport in humans. We also applied injection angiography to study the arterial response of a limb undergoing bone transport. This model includes a proximal osteotomy and bone transport to fill in a segmental tibial diaphyseal defect. Regenerate bone formed well in the gap that was created that trailed the transport segment, and slow healing at the docking site was observed, as seen in humans. The angiographic techniques clearly revealed, by radiography and anatomic dissection, the arterial response to bone transport. The results showed that the transport segment had an arterial supply after osteotomy and after transport. They also demonstrated an extensive increase in vessels in limbs that had undergone distraction osteogenesis, an observation made clinically in humans but not well demonstrated experimentally. Furthermore, angiography showed proximal stretching and distal kinking of the major artery of the leg. This model closely resembles distraction osteogenesis through bone transport in humans and definitively demonstrates that the transport segment can maintain blood supply and remain viable during the transport process. The results of this study provide a basis for further work on factors that enhance and interfere with successful bone transport in humans.