Long-term changes in cerebrovascular reactivity following EC-IC bypass for intracranial steno-occlusive disease.
The purpose of this retrospective observational study is to investigate the long-term changes in cerebrovascular reactivity (CVR) as a measure of cerebral hemodynamics in patients with intracranial steno-occlusive disease (IC-SOD) after they have undergone an Extracranial-intracranial (EC-IC) bypass. Twenty-six patients suffering from IC-SOD were selected from our CVR database. Nineteen patients underwent unilateral and 7 underwent bilateral revascularization. CVR measurements were done using BOLD-MRI and precisely controlled CO2 and expressed as ΔBOLD (%)/Δ PETCO2 (mmHg). Trends in CVR over time were compared in both vascularized and non-vascularized hemispheres. Repeated measures analysis of variance with Greenhouse-Geisser correction was used to determine CVR changes within the grey matter MCA for longitudinal assessments. Overall, re-vascularized hemisphere showed a significant increase in CVR at the first follow-up, followed by a slight decrease at the second follow-up that significantly increased compared to the pre-bypass. However, the changes in the postoperative CVR were quite variable across the patients. Similar variability was seen in subsequent follow-ups, with a slight overall decline in the long term CVR as compared with first post-operative CVR. Our study demonstrates that EC-IC bypass has a beneficial long-term effect on cerebral hemodynamics and this effect varies between patients probably due to the variability in the underlying vascular pattern receiving the bypass. Hence, in the postoperative follow-up of patients routine functional imaging to monitor cerebral hemodynamics may be useful as the risk of stroke and cognitive decline remain present with impaired CVR.
['Rosen|Casey|C|', 'McKetton|Larissa|L|', 'Russell|Jeremy|J|', 'Sam|Kevin|K|', 'Poublanc|Julien|J|', 'Crawley|Adrian|A|', 'Han|Jay S|JS|', 'Sobczyk|Olivia|O|', 'Duffin|James|J|', 'Mandell|Danny M|DM|', 'Tymianski|Michael|M|', 'Fisher|Joseph A|JA|', 'Mikulis|David J|DJ|', 'Venkatraghavan|Lashmi|L|']
D000293:Adolescent D000328:Adult D000368:Aged D001921:Brain D002548:Cerebral Revascularization D002560:Cerebrovascular Circulation D002561:Cerebrovascular Disorders D005260:Female D006439:Hemodynamics D006801:Humans D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D012189:Retrospective Studies
Cerebrovascular reactivity Blood-oxygen-level dependent magnetic resonance imaging Extracranial-intracranial bypass Steno occlusive disease