Schulz Ursula G, Briley Dennis, Meagher Tom, Molyneux Andrew, Rothwell Peter M
Stroke Prevention Research Unit, Department of Clinical Neurology, Radcliffe Infirmary, Woodstock Road, Oxford OX2 6HE, UK.
Stroke. 2004 Nov;35(11):2459-65. doi: 10.1161/01.STR.0000143455.55877.b9. Epub 2004 Sep 16.
Many patients with transient ischemic attack (TIA) or minor stroke present to medical attention after a delay of several days or weeks, at which time it may be more difficult to obtain a clear history and clinical signs may have resolved. Because ischemic lesions on diffusion-weighted MRI (DWI) often persist for several weeks, we hypothesized that adding DWI to a standard protocol with T2-weighted imaging might be useful in the management of patients presenting late.
We studied consecutive patients with TIA or minor stroke presenting > or =3 days after the event. Two independent observers recorded the presence or absence of recent ischemic lesions on 2 different occasions, first with the T2 scan only, and second with T2 and DWI. Each time, with the aid of a written clinical summary, the observers recorded their diagnosis and proposed management.
300 patients (159 men) were scanned at a median of 17 (interquartile range=10 to 23) days after symptom onset. DWI showed a high signal lesion in 114/164 (70%) minor strokes versus 17/136 (13%) TIAs (P<0.0001). The presence of high-signal lesions on DWI decreased nonlinearly with time since symptom onset (P<0.0001) and increased with National Institutes of Health Stroke Score (P=0.038) and with age (P=0.01). In 90/206 (43.7%) patients with 1 or multiple lesions on T2, DWI helped to clarify whether these were related to a recent ischemic event (79 [48%] strokes; 11 [31%] TIAs). Compared with T2 alone, DWI provided additional information in 108 (36%) patients (91 [56%] strokes and 17 [13%] TIAs), such as clarification of clinical diagnosis (18 patients, 6%) or vascular territory (28 patients, 9.3%), which was considered likely to influence management in 42 (14%) patients (32 [19%] strokes; 10 [7.4%] TIAs).
The clinically useful information available from DWI provides a further justification for an MRI-based imaging protocol in patients with subacute TIA or minor stroke.
许多短暂性脑缺血发作（TIA）或轻度卒中患者在数天或数周后才就医，此时可能更难获取清晰的病史，且临床体征可能已消失。由于扩散加权磁共振成像（DWI）上的缺血性病变通常会持续数周，我们推测在标准的T2加权成像方案中增加DWI，可能有助于诊治延迟就诊的患者。
我们研究了症状发作≥3天后连续就诊的TIA或轻度卒中患者。两名独立观察者在两个不同时间记录近期缺血性病变的有无，第一次仅进行T2扫描，第二次同时进行T2和DWI扫描。每次，观察者借助书面临床总结记录他们的诊断并提出治疗方案。
300例患者（159例男性）在症状发作后的中位时间为17天（四分位间距=10至23天）时接受扫描。在114/164例（70%）轻度卒中患者中，DWI显示高信号病变，而在17/136例（13%）TIA患者中也有显示（P<0.0001）。DWI上高信号病变的出现率随症状发作后的时间呈非线性下降（P<0.0001），并随美国国立卫生研究院卒中量表评分（P=0.038）和年龄（P=0.01）增加。在T2上有1个或多个病变的90/206例（43.7%）患者中，DWI有助于明确这些病变是否与近期缺血事件相关（79例[48%]为卒中；11例[31%]为TIA）。与仅使用T2相比，DWI为108例（36%）患者（91例[56%]为卒中，17例[13%]为TIA）提供了额外信息，如明确临床诊断（18例患者，6%）或血管区域（28例患者，9.3%），这被认为可能会影响42例（14%）患者（32例[19%]为卒中；10例[7.4%]为TIA）的治疗。
DWI提供的具有临床实用价值的信息，为基于MRI的成像方案用于亚急性TIA或轻度卒中患者提供了进一步的依据。
