After the first few days, there is a well-known phase of parenchymal contrast enhancement caused by leakage of contrast material across the disrupted blood-brain barrier. Moreover, T2-weighted imaging is more sensitive than T1-weighted imaging in detecting ischemic changes, and administration of paramagnetic gadolinium chelates (7) before T1-weighted imaging can provide valuable information (8).Įlster and Moody (9) reported two patterns of MR contrast enhancement in the acute phase of ischemic stroke: intravascular enhancement and meningeal enhancement. MR imaging is more sensitive than CT in detecting ischemic changes (5, 6). Use of contrast medium with CT in the acute phase of stroke has not generally been useful (4). In published reports of acute stroke trials, CT has been used to exclude hemorrhage and extensive ischemic changes (1–3). The acute phase of stroke has been studied intensely, because treatment should be given as soon as possible after the onset of symptoms. Ischemic stroke is a prominent cause of death and disability in industrialized countries. Parenchymal enhancement may be intense and can cause diagnostic uncertainty in cases in which the clinical history is obscure. Intravascular enhancement over a larger area than the infarct on diffusion-weighted images on day 1 was not associated with the extent of infarct growth.ĬONCLUSION: Detection of different patterns of contrast enhancement can help in determining the age of infarct. Parenchymal enhancement was detected in 26%, 56%, and 100% of the cases, respectively. RESULTS: Intravascular enhancement in the infarcted area was detected on day 1 in 78% of the cases, on day 2 in 78% of the cases, and at 1 week in 30% of the cases. Enhancement findings were categorized as intravascular and parenchymal, with further categorization of parenchymal enhancement as cortical, subcortical, and deep these findings were then compared with diffusion-weighted imaging findings. Diffusion-weighted imaging was performed at the same slice positions. T1-weighted spin-echo imaging was performed before and after a 0.2 mmol/kg bolus of gadolinium chelate. METHODS: Forty-eight patients were imaged on the first and second days and again 1 week after the onset of ischemic stroke. The aims of this study were to study the different MR enhancement findings during the first week after stroke and to ascertain whether the presence of intravascular enhancement over a larger area than the infarct on diffusion-weighted images on day 1 is able to predict substantial infarct growth during the first week.

Diffusion-weighted MR imaging depicts infarct within minutes after the onset of symptoms. BACKGROUND AND PURPOSE: Intravascular and parenchymal enhancement have been detected with contrast-enhanced T1-weighted MR imaging in patients with ischemic stroke.

Mr contrast injection