High rate of complete recanalization and dramatic clinical recovery during tPA infusion when continuously monitored with 2-MHz transcranial Doppler monitoring

Diffusion-weighted lesions in stroke patients with transient symptoms--where are they located?

BACKGROUND

MR diffusion-weighted imaging (DWI) has revolutionized neuroimaging and contributed to a tissue-based redefinition of transient ischemic attack (TIA). Stroke patients with DWI lesions may have neurological symptoms that resolve completely within 24 h, suggesting successful vessel recanalization. Prior studies of stroke patients with transient symptoms have not found any predilection for DWI lesions in any specific territory. Other studies have, however, reported an association between higher brain dysfunction and presence of DWI lesions in patients with transient ischemic symptoms, suggesting a high rate of cortical affection in these patients. We sought to see whether DWI location in stroke patients with transient symptoms <24 h differed from those with persistent symptoms ≥ 24 h. We hypothesized an association between transient symptoms <24 h and cortical DWI lesion localization due to a possible higher rate of vessel recanalization in patients with transient symptoms causing distal cortical infarctions.

METHODS

Ischemic stroke patients examined with DWI and admitted within 24 h after symptom onset between February 2006 and November 2013 were prospectively registered in a database (The Bergen NORSTROKE Registry). Based on neurological examination 24 h after admission, patients were classified as having either transient symptoms <24 h (DWI <24) or persistent symptoms ≥ 24 h (DWI ≥ 24). DWI lesions were classified into different groups depending on lesion location: cortical lesions, confined to the supratentorial cortex; large subcortical lesions, located in the hemispheric white matter, basal ganglia, internal capsule, thalamus or corona radiate with a diameter ≥ 15 mm; lacunar lesions, located in the same territory as large subcortical lesions with a diameter <15 mm; mixed cortical-subcortical lesions, located in both supratentorial cortex and subcortex; cerebellar lesions, confined to the cerebellum; brain stem lesions, confined to the brain stem; multiple locations, located in more than one of the above defined areas.

RESULTS

A total of 142 ischemic stroke patients had DWI <24 and 830 DWI ≥ 24. Cortical DWI location was more frequent in patients with DWI <24 (54.2% vs. 29.5%, p < 0.001), while proportions of mixed cortical-subcortical lesions (13.4% vs. 26.5%, p = 0.001) and lesions with multiple locations (5.6% vs. 11.1%, p = 0.048) were less frequent as compared to DWI ≥ 24. Cortical DWI location was independently associated with DWI <24 when adjusted for confounders in multiple regression analyses (OR 1.89, 95% CI 1.28-2.81, p = 0.001).

CONCLUSION

Cortical DWI location was independently associated with transient stroke symptoms <24 h. This may be explained by vessel recanalization, resulting in upstream transportation of remaining particles and distal cortical lesions.

Emergent angioplasty and stent placement recanalization without thrombolysis in acute middle cerebral artery occlusions

A significant proportion of patients with infarcts from large-vessel lesions have shown a poor response to systemic thrombolysis. Stents have been used to recanalize occluded or severely stenosed intracranial arteries in patients with acute stroke. This study evaluated the feasibility, efficacy, and safety of intracranial artery recanalization for acute middle cerebral artery (MCA) occlusion using emergent angioplasty and stent placement without thrombolysis. All patients from a retrospectively collected database who met the inclusion criteria and were treated with an intracranial stent for acute MCA occlusion were included. Treatment comprised angioplasty and stenting without interventional thrombolytic therapy. Recanalization was assessed by angiography immediately after stent placement based on the Thrombolysis in Myocardial Infarction (TIMI) score. Complications related to the procedure and outcomes were assessed. Neurologic status was evaluated before and after treatment. Eleven patients were treated with emergent angioplasty and stent placement. Partial or complete recanalization (TIMI 2 and 3) was achieved in 11 patients (100%) assessed by digital subtraction angiography immediately after MCA stenting. One patient died due to reocclusion of MCA 2 days after the procedure. Among the survivors, 7 patients (70%) had a good outcome (modified Rankin Scale score, 0-2) and 3 patients (30%) had a moderate outcome (modified Rankin Scale score, 3). Follow-up computed tomography angiography or magnetic resonance angiography revealed mild restenosis in 2 of the 10 patients. This preliminary experience demonstrates the technical feasibility and high rate of recanalization with emergent angioplasty and stenting without thrombolysis in patients with acute MCA occlusion.