Ramsay S C, Yeates M G, Lord R S, Hille N, Yeates P, Eberl S, Reid C, Fernandes V
Department of Nuclear Medicine, St. Vincent's Hospital, Sydney, Australia.
J Nucl Med. 1991 Jul;32(7):1382-6.
Cerebral perfusion through stenosed internal carotid arteries is usually maintained by autoregulation. However, flow reserve may be reduced, suggesting hemodynamically significant stenosis, and such reduction should be improved by carotid endarterectomy. This concept was studied in 20 subjects with unilateral internal carotid artery stenosis (major stenosis greater than or equal to 70%, minor stenosis less than or equal to 50%). Thirteen had experienced recent transient ischemic attacks and seven had no definite focal symptoms. Subjects underwent Tc-HMPAO cerebral SPECT during acetazolamide dysautoregulation before and after internal carotid endarterectomy. Nine (45%) had perfusion defects that improved after surgery, suggesting surgery had improved cerebral flow reserve. Seven had defects that did not improve after surgery. Four had worsened or new defects after surgery, suggesting perioperative infarcts. The relatively large proportion of patients with improved cerebral blood flow reserve after surgery suggests that this technique may have a significant role to play in assessing which patients might benefit from carotid endarterectomy.
通过狭窄的颈内动脉的脑灌注通常由自身调节维持。然而，血流储备可能会降低，提示存在血流动力学上有显著意义的狭窄，而这种降低应通过颈动脉内膜切除术得到改善。在20例单侧颈内动脉狭窄（主要狭窄大于或等于70%，次要狭窄小于或等于50%）的受试者中对这一概念进行了研究。其中13例近期经历过短暂性脑缺血发作，7例无明确的局灶性症状。受试者在颈动脉内膜切除术前后的乙酰唑胺失自身调节期间接受了Tc-HMPAO脑SPECT检查。9例（45%）有灌注缺损，术后得到改善，提示手术改善了脑血流储备。7例术后缺损未改善。4例术后缺损恶化或出现新的缺损，提示围手术期梗死。术后脑血流储备得到改善的患者比例相对较高，这表明该技术在评估哪些患者可能从颈动脉内膜切除术中获益方面可能发挥重要作用。
