Titanium wound chambers for wound healing research

Standardized and reproducible animal models are crucial in medical research. Rodents are commonly used in wound healing studies since, they are easily available, affordable and simple to handle and house. However, the most significant limitation of rodent models is that the wounds heal by contraction while in humans the primary mechanisms of healing are reepithelialization and granulation tissue formation. The robust contraction results in faster wound closure that complicates the reproducibility of rodent studies in clinical trials. We have developed a titanium wound chamber for rodent wound healing research. The chamber is engineered from two pieces of titanium and is placed transcutaneously on the dorsum of a rodent. The chamber inhibits wound contraction and provides a means for controlled monitoring and sampling of the wound environment in vivo with minimal foreign body reaction. This technical report introduces two modalities utilizing the titanium chambers in rats: (1) Wound in a skin island model and, (2) Wound without skin model. Here, we demonstrate in rats how the “wound in a skin island model” slows down wound contraction and how the “wound without skin” model completely prevents the closure. The titanium wound chamber provides a reproducible standardized models for wound healing research in rodents.     

Measurement of common carotid artery lumen dynamics during the cardiac cycle using magnetic resonance TrueFISP cine imaging

Purpose

To demonstrate magnetic resonance (MR) measurements of vascular lumen dynamics in common carotid arteries by using true fast imaging with steady‐state precession (TrueFISP) cine imaging with an aim to provide additional physiologic information on the vessels.

Materials and Methods

The left and right common carotid arteries were studied in normal young men (N = 6; age = 21–24 years; body weight = 130–175 lbs) using electrocardiogram (ECG)‐triggered TrueFISP cine imaging at 20 frames per cardiac cycle. Lumen area waveforms were characterized with specific time and amplitude ratios. Distension values were quantified.

Results

Distension values were measured at 25.92 ± 2.58% and 27.58 ± 4.44% for the left and right common carotid arteries, respectively. These findings are consistent with those previously documented using ultrasound imaging in a similar age group. Consistent lumen area waveform characteristics were found among the subjects studied.

Conclusion

These findings demonstrate for the first time that the use of TrueFISP cine imaging is a robust, rapid technique for quantifying carotid lumen area dynamics and distension, which may be valuable in characterizing and diagnosing cardiovascular diseases. J. Magn. Reson. Imaging 2008;28:1527–1532. © 2008 Wiley‐Liss, Inc.