BACKGROUND AND PURPOSE: Rarely, acute ischemic stroke (AIS) patients have pretreatment CT-CBV abnormalities larger than final infarct volumes. We sought to determine: (1) the prevalence of CT-CBV "reversibility" in AIS patients treated with thrombolytic therapy, and (2) whether the presumed tissue salvage of these CT-CBV lesions depends on the CTP software. METHODS: We reviewed the admission CT-CBV maps (calculated with an algorithm sensitive to tracer arrival time) and follow-up images of 148 AIS patients who received thrombolytic therapy. When the follow-up infarct appeared smaller than the admission CT-CBV lesion, the CTP source images were reprocessed using "delay-correction" software (GE, CTP 4). Original and "delay-corrected" CT-CBV ischemic lesion volumes were compared to each other and follow-up infarct volumes using the Student t test. RESULTS: 11/148 (7.4%) patients had admission CT-CBV larger than follow-up lesions (mean difference -69.5 cc, range -146.0 to -14.0 cc; P<0.05). For all patients, the admission CT-CBV lesions were smaller on the delay- versus nondelay-corrected maps (mean difference -83.1, range -233 to -2 cc; P<0.05). Only 2 patients had delay-corrected CT-CBV lesions larger than follow-up infarctions, with a 12- to 17-cc difference in volume. 7/9 of the remaining patients had extracranial hemodynamic factors potentially delaying tracer arrival, including atrial fibrillation (AF; n=4), congestive heart failure (CHF; n=4), or extracranial internal carotid artery (ICA) stenosis (n=1). CONCLUSIONS: True "reversibility" of CT-CBV "core" lesions in AIS patients after thrombolytic therapy is rare, with small volumes of "salvaged" tissue. Pseudoreversibility of core lesions in standard CT-CBV maps can be avoided by using specific algorithmically optimized delay-correction software. Further investigation is warranted to determine whether this finding applies to algorithms provided by other vendors.
BACKGROUND AND PURPOSE: Rarely, acute ischemic stroke (AIS) patients have pretreatment CT-CBV abnormalities larger than final infarct volumes. We sought to determine: (1) the prevalence of CT-CBV "reversibility" in AISpatients treated with thrombolytic therapy, and (2) whether the presumed tissue salvage of these CT-CBV lesions depends on the CTP software. METHODS: We reviewed the admission CT-CBV maps (calculated with an algorithm sensitive to tracer arrival time) and follow-up images of 148 AISpatients who received thrombolytic therapy. When the follow-up infarct appeared smaller than the admission CT-CBV lesion, the CTP source images were reprocessed using "delay-correction" software (GE, CTP 4). Original and "delay-corrected" CT-CBVischemic lesion volumes were compared to each other and follow-up infarct volumes using the Student t test. RESULTS: 11/148 (7.4%) patients had admission CT-CBV larger than follow-up lesions (mean difference -69.5 cc, range -146.0 to -14.0 cc; P<0.05). For all patients, the admission CT-CBV lesions were smaller on the delay- versus nondelay-corrected maps (mean difference -83.1, range -233 to -2 cc; P<0.05). Only 2 patients had delay-corrected CT-CBV lesions larger than follow-up infarctions, with a 12- to 17-cc difference in volume. 7/9 of the remaining patients had extracranial hemodynamic factors potentially delaying tracer arrival, including atrial fibrillation (AF; n=4), congestive heart failure (CHF; n=4), or extracranial internal carotid artery (ICA) stenosis (n=1). CONCLUSIONS: True "reversibility" of CT-CBV "core" lesions in AISpatients after thrombolytic therapy is rare, with small volumes of "salvaged" tissue. Pseudoreversibility of core lesions in standard CT-CBV maps can be avoided by using specific algorithmically optimized delay-correction software. Further investigation is warranted to determine whether this finding applies to algorithms provided by other vendors.
Authors: Shahmir Kamalian; Shervin Kamalian; Matthew B Maas; Greg V Goldmacher; Seyedmehdi Payabvash; Adnan Akbar; Pamela W Schaefer; Karen L Furie; R Gilberto Gonzalez; Michael H Lev Journal: Stroke Date: 2011-05-05 Impact factor: 7.914
Authors: Branko N Huisa; William P Neil; Ronald Schrader; Marcel Maya; Benedict Pereira; Nhu T Bruce; Patrick D Lyden Journal: J Stroke Cerebrovasc Dis Date: 2012-12-14 Impact factor: 2.136