Cooke George R, Blake Sarah R, Wood Emma
Guildford Radiology Group.
Radiol Case Rep. 2020 Sep 10;15(11):2262-2265. doi: 10.1016/j.radcr.2020.08.041. eCollection 2020 Nov.
Patients who have undergone a Fontan's procedure have an abnormal circulation that presents a unique challenge when performing computed tomography pulmonary angiograms. In a standard imaging protocol, contrast is injected into the upper limb veins that feed into the superior vena cava. In Fontan's patients the Computed tomography pulmonary angiograms bypasses the heart and preferentially fills the right lung, with only a small amount of mixture of contrast and noncontrast blood in the pulmonary arteries. In this article, we present the case of a 35-year-old female complaining of chest and abdominal pain with oxygen saturations of 85% on room air. Computed tomography pulmonary angiograms showed suboptimal imaging of the left lung and apparent filling defects in the right lung suggesting a radiological diagnosis of a pulmonary embolism. The abnormal flow and distribution of contrast in the pulmonary arteries can result in a false positive diagnosis of pulmonary embolism. To overcome this, experts advise using a dual-injection of contrast via upper and lower limb central veins to achieve optimal imaging.
接受过Fontan手术的患者循环系统异常，这给进行计算机断层扫描肺动脉造影带来了独特挑战。在标准成像方案中，造影剂注入汇入上腔静脉的上肢静脉。在Fontan手术患者中，计算机断层扫描肺动脉造影绕过心脏，优先充盈右肺，肺动脉中只有少量造影剂和非造影剂血液混合。在本文中，我们介绍了一名35岁女性病例，该患者主诉胸痛和腹痛，在室内空气中氧饱和度为85%。计算机断层扫描肺动脉造影显示左肺成像欠佳，右肺有明显充盈缺损，提示放射学诊断为肺栓塞。肺动脉中造影剂的异常流动和分布可能导致肺栓塞的假阳性诊断。为克服这一问题，专家建议通过上肢和下肢中心静脉双注射造影剂以实现最佳成像。
