Changes in cerebral hemodynamic and cognitive parameters after external carotid–internal carotid bypass surgery in patients with severe steno-occlusive disease: A pilot study

• Published in: Journal of the neurological sciences 2012-11, Vol.322 (1), p.112-116
• Main Authors: Dong, YanHong, Teoh, Hock Luen, Chan, Bernard P.L, Ning, Chou, Yeo, Tseng Tsai, Sinha, Arvind K, Venketasubramanian, Narayanaswamy, Slavin, Melissa J, Sachdev, Perminder, Collinson, Simon L, Chen, Christopher, Sharma, Vijay K
• Format: Article
• Language: English
• Subjects: Adult; Aged; Attention; Carotid Stenosis - surgery; Cerebral hemodynamics; Cerebrovascular Circulation - physiology; Cognition; Cognition Disorders - diagnostic imaging; Cognition Disorders - etiology; Coronary Artery Bypass - adverse effects; External carotid–internal carotid (EC/IC) bypass surgery; Female; Hemodynamics - physiology; Humans; Indexing in process; Intracranial stenosis; Language; Learning; Male; Middle Aged; Neurology; Neuropsychological Tests; Pilot Projects; Postoperative Complications - diagnostic imaging; Postoperative Complications - etiology; Prospective Studies; SPECT; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Transcranial Doppler; Ultrasonography, Doppler, Transcranial
• ISSN: 0022-510X; 1878-5883
• DOI: 10.1016/j.jns.2012.07.034

Abstract Background The direct impact of external carotid–internal carotid (EC-IC) bypass surgery on cognition of patients with severe steno-occlusive disease of internal carotid (ICA) or middle cerebral artery (MCA) is unknown. In this pilot study, we evaluated changes in cerebral hemodynamic and cognition in these patients. Methods Patients with severe steno-occlusive disease and impaired cerebral vasodilatory reserve (CVR) with transcranial Doppler (TCD) breath holding index (BHI) and acetazolamide-challenged HMPAO-Single Photon Emission Tomographic (SPECT) imaging were offered EC-IC bypass surgery. CVR and cognitive performance using a formal neuropsychological battery were evaluated before and 3–6 months after surgery. Results Nine patients and 9 matched controls were recruited. Significant CVR improvement from TCD-BHI [median 0 (Inter-quartile range IQR 0.45) to 1.10 (IQR 0.73), p < 0.001] and SPECT ( p < 0.001) was observed in surgery patients. EC-IC bypass patients had significant improvement in verbal memory ( p = 0.037) and executive function ( p = 0.043) and a trend of improvement in visual memory ( p = 0.052) compared to controls. Conclusion EC-IC bypass surgery in carefully selected patients could improve cerebral hemodynamics and verbal memory and executive function.