The substantial power strain driving the injection is important to compensate for your modest caliber lumen and higher resistance within the injection catheters . The substantial electrical power can be desired to realize the higher movement velocity for bolus injections. This device reproducibly injects volumes as minor as 6 microL at one to two microL/ms. The contrast agent we have now made use of is Isovue containing 370 mg/ml iodine . The contrast agent was heated to the entire body temperature in the rat, eliminating thermal shock and cutting down contrast viscosity. The animal procedures have been approved through the Duke Institutional Animal Care and Use Committee. We implemented 10 male 1112 weekold SASSD rats . Animals were primary anesthetized with Nembutal with an IP dose of 60 mg/kg). The rats have been perorally intubated and mechanically ventilated at 80 breaths per minute applying an inhouse created ventilator .
A PE50 catheter was inserted to the proper prevalent carotid artery and state-of-the-art in to the aortic arch. The catheter tip was positioned just cranial to your aortic valve working with realtime blood stress guidance. Since the catheter was state-of-the-art, the diastolic strain dropped to zero indicating the tip was in selleck chemical braf inhibitors the left ventricle, then the catheter was slowly withdrawn until the typical systolic/diastolic strain appeared, which indicated that the tip was inside the aorta just beyond the aortic valve, and last but not least, the catheter was withdrawn an extra three to 5 mm to position inside the ascending aorta and secured on this ultimate position. For the duration of imaging, anesthesia was maintained with isoflurane delivered by mechanical ventilation. Ordinary body temperature was maintained applying heat lamps plus a feedback PID controller by using input from a rectal thermistor.
Pediatric electrodes were taped to the footpads for ECG . A pneumatic pillow on the thorax recorded breathing motion . All physiologic signals have been acquired with LabLinc V amplifiers and have been displayed on the computer system implementing a customized LabVIEW application. IV. Imaging sequence A custom sequencecontroller application implemented in LabVIEW was utilized to synchronize xray exposure hif 1 inhibitor and contrast injection with cardiac activity and ventilation. The bolus injection time and duration are exactly synchronized together with the xray publicity by this controller . The sequence begins by spinning the highspeed xray rotor, stopping ventilation during endexpiration, and acquiring a set of noncontrast pictures at a particular delay after the ECG R wave; these pictures are applied to produce the mask.
With out interruption, this is often followed by a bolus injection of contrast on the exact same delay time following the R wave, after which a series of postinjection images is obtained also concurrently in the cardiac cycle.