电子束CT在右室双出口室间隔缺损分型诊断中的临床价值

Clinical application of electron beam CT in the diagnosis of ventricular septal defect classification of double outlet right ventricle

目的 探讨电子束CT(EBCT)在右室双出口室间隔缺损 (VSD)分型诊断中的临床价值。方法 对经EBCT检查 ,手术或心血管造影证实、不合并完全性心内膜垫缺损的右室双出口病例 14例行回顾性分析。男 10例 ,女 4例。年龄 1～ 2 9岁 ,平均 9 7岁。EBCT均采用单层无间隔增强扫描 ,层厚 3mm。重点观察和测量以下内容 :VSD上缘与主动脉瓣、肺动脉瓣下缘及三尖瓣环上缘的位置关系与距离 ;肌性流出道的位置 ,大动脉有无骑跨。距离以所在层面床位差计。结果 (1)主动脉瓣下VSD 7例 ,缺损与主动脉瓣和肺动脉瓣的距离均数分别为 5 6和 15mm ,有极显著性差异 (t=4 6 9,P <0 0 0 5 )。所有主动脉瓣所在层面均低于肺动脉瓣 ,且靠近VSD ,3例主动脉瓣骑跨于VSD。 (2 )肺动脉瓣下VSD 4例 ,缺损与肺动脉瓣和主动脉瓣的距离均数为 3和 9mm ,有显著性差异 (t=4 91,P <0 0 5 )。所有肺动脉瓣所在层面均低于主动脉瓣 ,且更接近VSD ,2例肺动脉瓣骑跨于VSD。 (3)主、肺动脉瓣下VSD 2例 ,缺损位于主、肺动脉瓣正下方 ,与两者距离为 0～ 1 5mm。前述 3型VSD ,除 1例上缘与三尖瓣环上缘相平外 ,均高于三尖瓣环。 (4)远离大动脉型 1例 ,VSD与主、肺动脉瓣距离分别为 30和 45mm ,VSD上缘低于三尖瓣环 30mm。结论 EBCT可精确显示右室?

Objective To explore the clinical application of electron beam CT (EBCT) in the diagnosis of ventricular septal defect (VSD ) classification of double outlet right ventricle. Methods Retrospective analysis of EBCT findings in 14 patients with double outlet right ventricle confirmed by operation or angiocardiography was done. The double outlet right ventricle patients complicated with complete endocardial cushion defect were not included in our research. The 10 male and 4 female patients ranged in age from 1 to 29 years (median age was 9 7 years). Serial 3mm contrast single slice mode scan without slice interval was obtained.We laid stress on observation and measurement as follows: (1) The location relationship and distances among upper borders of VSD and tricuspid annulus, lower borders of aortic and pulmonary valves. (2) Location of muscular outlet. (3) Overriding of great arteries. All the distances were calculated by means of the difference of examination table perch. Results (1) In the 7 patients with subaortic VSD, the mean distance between VSD and aortic valve was 5.6 mm while that between VSD and pulmonary valve was 15 mm. The difference had extreme statistic significance ( t = 4.69, P <0.005). The level of aortic valve was lower than that of pulmonary valve and closer to VSD in all the patients. Aortic valve overrode VSD in 3 patients. (2) In the 4 patients with subpulmonary VSD, the mean distance between VSD and pulmonary valve was 3 mm while that between VSD and aortic valve was 9 mm. There was significant difference ( t = 4.91, P <0.05). The level of pulmonary valve was lower than that of aortic valve and closer to VSD in all the patients. Pulmonary valve overrode VSD in 2 patients.(3) 2 patients with doubly committed VSD, the VSD situated directly under the aortic and pulmonary valve. The distance between VSD and aortic or pulmonary valve was 0-1.5 mm. In the above mentioned three types VSD, the upper border of VSD was higher than that of tricuspid annulus in all patients but 1 patient being on the same level. (4) 1 patient with non committed VSD, the distance between VSD and aortic valve was 30 mm while that between VSD and pulmonary valve was 45 mm. The upper border of VSD was 30 mm lower than that of tricuspid annulus′. Conclusion EBCT was valuable in accurately outlining the location of VSD in double outlet right ventricle. VSD classification of double outlet right ventricle may be easily determined by means of the situation relationship among aortic valve, pulmonary valve and tricuspid valve in EBCT.