Blood pressure in the artery distal to an intraarterial embolus during thrombolytic therapy for occlusion of a major artery: a predictor of cerebral infarction following good recanalization.

OBJECT: The aim in this study was the investigation of back pressure in arteries distal to the occlusion site during intraarterial thrombolysis as well as the usefulness of back pressure measurement in combination with diffusion-weighted (DW) magnetic resonance (MR) imaging to predict the occurrence of ischemic lesions following good recanalization. METHODS: . Twenty-five consecutive patients with severe hemiparesis caused by embolism of the internal carotid artery (10 patients) and the proximal middle cerebral artery (15 patients) were treated using intraarterial thrombolysis. Systolic back pressure, measured through a microcatheter in the artery just distal to the emboli, ranged from 22 to 78 mm Hg. According to an angiographic inclusion criterion for good recanalization--that is, recanalization of the M2 or more distal arteries at the end of thrombolysis--21 of 25 patients underwent evaluation in this study. In 14 patients volumes of low-density areas on computerized tomography (CT) scans obtained 2 months postthrombolysis were smaller in comparison with volumes of hyperintense areas on DW MR images acquired before treatment, whereas these low-density areas were larger in seven patients. Compared with those on initial DW MR images, the volume of abnormalities on CT scans obtained 2 months posttreatment were significantly reduced in patients with a systolic back pressure greater than 30 mm Hg (16 patients) than in those with a back pressure of 30 mm Hg or less (five patients) (p < 0.05). Systolic back pressures greater than 30 mm Hg were associated with significantly better modified Rankin Scale scores than those 30 mm Hg or less (p < 0.05). CONCLUSIONS: Back pressure measurement in combination with DW MR imaging can be used to predict the occurrence of infarction as demonstrated on CT scans following thrombolysis.

Striatal hyperintensity on T1-weighted magnetic resonance images and high-density signal on CT scans obtained in patients with hyperglycemia and no involuntary movement. Report of two cases.

The authors report on two patients in whom an increased signal on T1-weighted magnetic resonance images and a high-density signal on computerized tomography scans of the striatum were demonstrated, both of which were associated with nonketotic hyperglycemia. Involuntary movements, which have been present in all previously reported cases, were not observed in either patient at any time during the entire course of illness. One patient displayed hemiparesis, whereas the other had dementia, gait disturbance, and urinary incontinence. Clinical and radiological abnormalities improved on control of blood glucose levels. Invasive studies, including biopsy procedures, should be avoided on encountering this disease given the good prognosis that results from simple medical treatment.