Imaging of pulmonary embolism and t-PA therapy effects using MDCT and liposomal iohexol blood pool agent: preliminary results in a rabbit model.

摘要: Rationale and Objectives. Polyethylene glycolcoated liposomal blood pool contrast agents maintain enhancement over several hours. This study aimed to evaluate (long-term) imaging of pulmonary arteries, comparing conventional iodinated with a agent. Also, visualization the (real-time) therapeutic effects tissue plasminogen activator (t-PA) on embolism (PE) was attempted. Materials Methods. Six rabbits (weight approximately 4 kg) had autologous clots injected through superior vena cava. Imaging performed using (iohexol, 350 mg I/ml; GE HealthCare, Princeton, NJ) at dose 1400 I per animal, after wash-out, animals were imaged an agent (88 I/mL, 900 I/animal). Subsequently, five 2 t-PA continued for up 4Ω Results. Both identified PE in trunk main arteries all rabbits. Liposomal yielded uniform enhancement, which remained relatively constant throughout experiments. Conventional exhibited nonuniform opacification rapid clearance postinjection. Three six mistimed bolus injections, requiring repeat injections. Following t-PA, embolus volume (central segmental) decreased four treated (range 1057%, mean 42%). One animal showed no response t-PA.