The diagnostic value of diffusion weighted imaging in transient ischemic attacks

Abstract

Objective To study the clinical significance of diffusion weighted imaging (DWI) positive lesions in transient ischemic attacks (TIA) patients, TIA patients with fully reversible lesions were compared with the other patients for investigating the predictive value of apparent diffusion coefficient(ADC) for distinguishing between TIA and stroke. Methods Fifty-seven patients hospitalized with TIA at Department of Neurology, Central Hospital of Baotou August 2009 to June 2011 were identified. All patients had brain magnetic resonance imaging within 24 h after onset, then they were divided into DWI positive group and negative group. A follow-up MR imaging or CT was available in patients of DWI positive group. According to MRI or CT, patients were divided into TIA group and cerebral infarction (CI) group. Clinical features and DWI Imaging were compared between the two groups. For each lesion, the quantitative parameters on initial DWI (ADC) were recorded, and comparisons between reversible and irreversible lesions were performed. Results The ADC values were (630.4±25.9)×10-3 mm2/s in lesions with TIA and (495.2±60.0)×10-3 mm2/s with brain infaction (t=6.669, P=0.000). The relative ADC ratio values were lower (62.6%±7.4% vs 82.1%±5.6%, t=7.013，P=0.000) in lesions with subsequent infarct than in those that were fully reversible. Conclusions ADC values are moderately decreased in DWI lesions from TIA patients, while ADC values are significantly decreased in CI group. It is useful to early distinguish TIA from CI by comparing ADC and rADC values. Key words: Diffusion magnetic resonance imaging; Ischemic attack; transient; Brain infarction; Diagnostic imaging