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

Abstract

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.

Retrobulbar Sinus Injection of Doxorubicin is More Efficient Than Lateral Tail Vein Injection at Inducing Experimental Nephrotic Syndrome in Mice: A Pilot Study

“…Beyond nephrology, there are also other uses, such as contrast media applications in radiological imaging studies, that are critically dependent upon rapid intravenous injection. 42…”

Comparison of haematopoietic stem cell engraftment through the retro-orbital venous sinus and the lateral vein: alternative routes for bone marrow transplantation in mice

“…As mentioned above, other studies have been published comparing the TV and RO administration routes that show similar results when delivering drugs, antibodies or cells in similar situations. [2][3][4][5][6]9 Also, in our hands, RO administration has shown greater consistency regarding donor chimerism levels due to the ease of the technique and the lower rate of failure.…”

“…Socher et al found that the RO administration of contrast media for cardiac perfusion studies in mice using computed tomography provided better cardiac imaging results than TV injections. 5 Some researchers have also claimed that RO administration causes less stress to the animals, although it was not until 2008 that Steel et al published some data to support this. The authors performed a direct comparison of TV and RO injections as IV drug delivery routes in mice.…”

Coronary micro-computed tomography angiography in mice

“…the left ventricular ejection fraction 4 , 5 , 22 – 24 . Recently, experimental time-resolved dual-energy imaging techniques have been introduced 25 and a single method for cardiac perfusion imaging became available 26 by using a novel contrast injection technique 27 . Furthermore, several contrast agents have been proposed that selectively accumulate in healthy myocardium.…”