Tissue Window versus Time Window? A Review of Patients Receiving Extended Hours Thrombolysis Guided By DWI-FLAIR Mismatch : Case Series

@#Introduction: Intravenous thrombolysis (IVT) is the gold standard for the treatment of patients with acute ischemic stroke (AIS) presenting within four and a half hours of onset. However, development of new thrombolytic agents and advanced imaging has led to extended time for thrombolysis based on advanced imaging. Here we describe four patients who presented in the extended hours; that benefitted from thrombolysis. Case series: We advocate magnetic resonance imaging (MRI) for AIS, that includes diffusion weighted imaging (DWI), apparent diffusion coefficient (ADC), fluid attenuated inversion recovery (FLAIR), susceptibility weighted imaging (SWI), and magnetic resonance angiography (MRA). We included four patients who were more than 18 years old, with National Institute of Health Stroke Scale (NIHSS) of six or more, presenting between four and a half to nine hours after stroke onset with no contraindications for intravenous thrombolysis. The imaging criteria used to determine eligibility for IVT is evidence of DWI-FLAIR mismatch on MRI. If FLAIR detects no signal change in the area of stroke on DWI, it is then termed DWIFLAIR mismatch, or FLAIR-negative – indicating high probability that the brain tissue is still viable, and that patients are good candidates for IVT. Conclusion: For patients with AIS who present within nine hours, DWI-FLAIR mismatch serves as an excellent surrogate marker of salvageable brain tissue, allowing a greater proportion of patients benefiting from this life-saving therapy. Our experience also shows that with careful patient selection, treatment with IVT can safely be given without an increased risk of bleeding or mortality.

Enfermedad de Creutzfeldt-Jakob por RMI: alteración cortical como signo temprano de la enfermedad / Creutzfeldt-Jakob disease by MRI: Cortical alteration as early sign disease

Se estudió por RMI un paciente de 59 años con diagnóstico probable de Enfermedad de Creutzfeldt-Jakob desde el inicio de sus síntomas. El paciente comienza con un cuadro de leve deterioro cognitivo. En una primera resonancia en secuencias FLAIR se visualiza hiperintensidad cortical a predomino de hemisferio izquierdo, no observándose en FSE T 2. Se hace más significativa en nueva resonancia en FLAIR y Difusión, con aparición de hiperintensidad en cabeza de ambos caudados y rápido deterioro cognitivo, alteraciones visuales, aparición de signos piramidales y extrapiramidales, convulsiones y mioclonias y mutismo. Con la acentuación de las alteraciones corticales -y en los ganglios de la base en una tercera resonancia-, el paciente trasforma su ECG de ritmo lento a un ritmo de punta-onda bifásico y trifásico. A 3 meses de la primera resonancia, nuevas imágenes muestran atrofia e importante hiperintensidad cortical y en ganglios de la base. En conclusión, las secuencias FLAIR y Difusión serían más sensibles que las secuencias T2 en la detección del aumento de intensidad de señal en la corteza cerebral, siendo un indicio diagnóstico temprano de la enfermedad de Creutzfeld-Jakob.

A 59-year-old man with probable Creutzfeldt-Jakob disease was studied from early symptoms. The patients manifested mild cognitive impairment. The first magnetic resonance showed hiperintense signal cortical abnormalities in FLAIR sequence predominantly in left hemisphere, FSE T2 no showed abnormalities. In other resonance those abnormities were more significative and appeared head of the caudate nucleus abnormalities in FLAIR and Diffusion-weighted, the patients began with rapidly progressing impairment, visual disturbance, pyramidal and extrapyramidal signs, seizures, myoclonus and mutism. The third resonance revealed cortical and basal ganglia high signal intensity abnormalities and the patient transformed slowing EEG to biphasic and triphasic sharp-waves. Three months later news imagines showed atrophy and very high signal intensity in cortical and basal ganglia. In conclusion: FLAIR and Diffusion-weighted sequences may be more sensitivity that T2 sequence, may be an early diagnostic clue of Creutzfeldt-Jakob.

The relation between diffusion tensor MRI appearances and cognition impairment in patient with ischaemic leukoaraiosis / 医学研究生学报

Objective:The changes both within lesions and normal-appearing white matter load on T2-weighted MRI in patients with ischemic leukoaraiosis(ILA) was investigated by diffusion tensor MRI(DTI) and the relation between the changes of DTI parameters and cognitive dysfunction was assessed.Methods: Thirty-four patiens with ischemic leukoaraiosis and 19 healthy volunteers underwent DTI,conventional MRI,and neuropsychological assessment. Results: In ILA group,on DTI,diffusity was increased within lesions and in normal-appearing white matter compared with the control group,FA was reduced.The changes of MD in the NAWM correlates with full scale intelligence quotient(IQ) and executive dysfunction,the changes of FA in the NAWM correlates with global cognitive impairment assessed by the MMSE. Conclusion: DTI can reveal pathological changes in normal-appearing white matter load on T2-weighted MRI in patients with ischemic leukoaraiosis,which correlates with cognitive dysfunctions.