The retrobulbar sinus is superior to the lateral tail vein for the injection of contrast media in small animal cardiac imaging.

Cardiac perfusion studies using computed tomography are a common tool in clinical practice. Recent technical advances and the availability of dedicated small animal scanners allow the transfer of these techniques to the preclinical sector in general and to mouse models of cardiac diseases in particular. This necessitates new requirements for contrast injection techniques as a rapid transport of contrast media from the intravenous access to the animal heart. Clinical contrast agents containing high iodine concentrations are used within small animal studies although they exhibit a high viscosity which might limit their transport within the vasculature. The authors provide a comparison of the transport of contrast media following an injection into the lateral tail vein and an injection into the retrobulbar sinus and discuss the anatomy involved. The temporal evolution of a contrast bolus and its in vivo distribution is visualized. It is demonstrated that injecting contrast agents into the lateral tail vein of mice results in a retrograde blood flow to the liver veins and therefore does not deliver a detectable contrast bolus to the heart, and thus it cannot be used for cardiac perfusion studies. By contrast, boli injected into the retrobulbar sinus are rapidly transported to the heart and provide ventricular contrast enabling perfusion studies similar to those in human patients. The results demonstrate that an injection into the retrobulbar sinus is superior to an injection into the lateral tail vein for the delivery of contrast boli to the animal heart, while all drawbacks of an injection into the lateral tail vein are overcome.

NBC Delta: special training beyond HAZMAT in the USA.

In response to a possible terrorist threat using nuclear, biological or chemical (NBC) weapons, the US government has set up a special Domestic Preparedness Program which includes a training section for paramedical and other responders to bridge the gap between a conventional HAZMAT incident and one involving NBC agents. The program, which is a partnership between six federal agencies, covers aspects of recognition and management of incidents which may not be within the normal experience of emergency medical services personnel, and builds upon their existing knowledge and training.