Fraser Douglas G W, Moody Alan R, Morgan Paul S, Martel Anne L, Davidson Ian
Department of Academic Radiology, University Hospital, Derby Road, Nottingham NG7 2UH, United Kingdom.
Ann Intern Med. 2002 Jan 15;136(2):89-98. doi: 10.7326/0003-4819-136-2-200201150-00006.
Current magnetic resonance techniques generate high signal from venous blood and show thrombi as filling defects. Magnetic resonance direct thrombus imaging (MRDTI) directly visualizes acute thrombus.
To determine the accuracy of MRDTI for diagnosis of acute symptomatic deep venous thrombosis (DVT) below and above the knee.
Prospective, blinded study.
A 1355-bed university hospital.
101 patients with suspected DVT who had had routine venography. Participants were recruited from a cohort of patients with suspected DVT. All patients with a positive venogram and one quarter of patients with a negative venogram were selected by using a random sequence.
MRDTI was performed within 48 hours of venography and was interpreted by two reviewers.
Diagnosis of DVT overall; isolated calf, femoropopliteal, and ileofemoral DVT; and thrombus in the calf, femoropopliteal, and iliac segments.
The reports from two readers had sensitivities of 96% and 94% and specificities of 90% and 92% for diagnosis of DVT. Sensitivities were 92% and 83% for isolated calf DVT, 97% and 97% for femoropopliteal DVT, and 100% and 100% for ileofemoral DVT. Specificities were 94% and 96% for isolated calf DVT and 100% and 100% for both femoropopliteal and ileofemoral DVT. Similarly, sensitivity and specificity within each of the venous segments ranged from 91% to 100%. Interobserver variability measured by using a weighted kappa statistic ranged from 0.89 to 0.98 for these measures.
Magnetic resonance direct thrombus imaging is an accurate noninvasive test for diagnosis of DVT, and its accuracy is maintained below the knee. Comparison of individual venous segments showed that results of MRDTI agreed strongly with findings on venography. Scanning was well tolerated, and interpretation was highly reproducible.
目前的磁共振技术可从静脉血中产生高信号，并将血栓显示为充盈缺损。磁共振直接血栓成像（MRDTI）可直接观察急性血栓。
确定MRDTI诊断膝下和膝上急性症状性深静脉血栓形成（DVT）的准确性。
前瞻性、盲法研究。
一家拥有1355张床位的大学医院。
101例疑似DVT且已接受常规静脉造影的患者。参与者从疑似DVT患者队列中招募。通过随机序列选择所有静脉造影阳性患者以及四分之一静脉造影阴性患者。
在静脉造影后48小时内进行MRDTI，并由两名阅片者解读。
总体DVT诊断；孤立性小腿、股腘和髂股DVT；小腿、股腘和髂段血栓。
两位阅片者的报告对DVT诊断的敏感性分别为96%和94%，特异性分别为90%和92%。孤立性小腿DVT的敏感性分别为92%和83%，股腘DVT的敏感性分别为97%和97%，髂股DVT的敏感性均为100%。孤立性小腿DVT的特异性分别为94%和96%，股腘和髂股DVT的特异性均为100%。同样，每个静脉段内的敏感性和特异性范围为91%至100%。通过加权kappa统计量测量的观察者间变异性在这些测量中范围为0.89至0.98。
磁共振直接血栓成像是诊断DVT的准确无创检查，其准确性在膝下也得以保持。对各个静脉段的比较表明，MRDTI结果与静脉造影结果高度一致。扫描耐受性良好，解读具有高度可重复性。
