Atar Eli, Kornowski Ran, Bachar Gil N
Department of Diagnostic Radiology, Hasharon Hospital, Rabin Medical Center, Petah Tikva, Israel.
Isr Med Assoc J. 2010 Nov;12(11):662-6.
Coronary CTangiography is an accurate imaging modality; however, its main drawback is the radiation dose. A new technology, the "step and shoot," which reduces the radiation up to one-eighth, is now available.
To assess our initial experience using the "step-and-shoot" technology for various vascular pathologies.
During a 10 month period 125 consecutive asymptomatic patients (111 men and 14 women aged 25-82, average age 54.9 years) with various clinical indications that were appropriate for step-and-shoot CCTA (regular heart rate < 65 beats/minute and body weight < 115 kg) were scanned with a 64-slice multidetector computed tomography Brilliance scanner (Philips, USA). The preparation protocol for the scan was the same as for regular coronary CTA. All examinations were interpreted by at least one experienced radiologist and one experienced interventional cardiologist. The quality of the examinations was graded from 1 (excellent imaging quality of all coronary segments) to 4 (poor quality, not diagnostic). There were 99 patients without a history of coronary intervention, 13 after coronary stent deployment (19 stents) and 3 after coronary artery bypass graft.
Coronary interpretation was obtained in 122 examinations (97.6%). The imaging quality obtained was as follows: 103 patients scored 1 (82.4%), 15 scored 2 (12%), 4 scored 3 (3.2%) and 3 scored 4 (2.4%). The grades were unrelated to cardiac history or type of previous examinations. Poor image quality occurred because of sudden heart rate acceleration during the scan (one patient), movement and respiration (one patient), and arrhythmia and poor scan timing (in one). Two patients were referred to percutaneous coronary intervention based on the CCTA findings, which correlated perfectly.
Step-and-shoot CCTA is a reliable technique and CCTA algorithm comparable to regular CCTA. This technique requires the lowest radiation dose, as compared to other coronary imaging modalities, that can be used for all CCTA indications based on the inclusion criteria of low (> 65 bpm) and stable heart rate.
冠状动脉CT血管造影是一种准确的成像方式；然而，其主要缺点是辐射剂量。现在有一种新技术，即“步进式扫描”，可将辐射剂量降低至八分之一。
评估我们使用“步进式扫描”技术诊断各种血管病变的初步经验。
在10个月期间，对125例连续的无症状患者（111名男性和14名女性，年龄25 - 82岁，平均年龄54.9岁）进行扫描，这些患者有各种适合步进式扫描冠状动脉CT血管造影的临床指征（静息心率<65次/分钟且体重<115千克），使用64排多层螺旋CT Brilliance扫描仪（美国飞利浦公司）进行扫描。扫描的准备方案与常规冠状动脉CT血管造影相同。所有检查至少由一名经验丰富的放射科医生和一名经验丰富的介入心脏病专家进行解读。检查质量从1级（所有冠状动脉节段成像质量优秀）到4级（质量差，无法诊断）进行分级。其中99例患者无冠状动脉介入史，13例曾接受冠状动脉支架置入术（共置入19个支架），3例曾接受冠状动脉旁路移植术。
122例检查（97.6%）获得了冠状动脉解读结果。获得的成像质量如下：103例患者评分为1级（82.4%），15例评分为2级（12%），4例评分为3级（3.2%），3例评分为4级（2.4%）。分级与心脏病史或先前检查类型无关。图像质量差是由于扫描期间心率突然加快（1例患者）、运动和呼吸（1例患者）以及心律失常和扫描时机不佳（1例患者）。基于冠状动脉CT血管造影结果，有2例患者被转诊进行经皮冠状动脉介入治疗，结果完全相符。
步进式扫描冠状动脉CT血管造影是一种可靠的技术，其CT血管造影算法与常规冠状动脉CT血管造影相当。与其他冠状动脉成像方式相比，该技术所需辐射剂量最低，基于低心率（>65次/分钟）和稳定心率的纳入标准，可用于所有冠状动脉CT血管造影指征。
