[Effect of thrombus endarterectomy (TEA) on the regional cerebral bloodflow (rCBF) in patients with unilateral internal carotid artery stenosis]

Abstract

Aim: In a study of patients with unilateral and symptomatic stenosis of the internal carotid artery (ICA), the effect of endarterectomy (EA) on the regional cerebral blood flow (rCBF) was tested over a postoperative interval of 12 months.

Method: Xenon-133-rCBF was assessed in 74 patients pre- and post-surgery (one week, six weeks, three months and 12 months after EA). This was done at rest and after stimulation with acetazolamide in order to test the perfusion reserve.

Results: Before surgery all 74 patients showed a diminished perfusion ipsilaterally-at rest and/or after stimulation. 38/74 (51%) patients had a significant (> 5%) and 36/74 (49%) patients a non-significant (< 5%) interhemispheric perfusion asymmetry. Twelve months after EA, there were only 23/74 (31%) patients with significant interhemispheric perfusion asymmetry. By stimulation, this decreasing effect became more evident: Before surgery 44/74 (60%) patients had a significant interhemispheric perfusion asymmetry, 12 months after surgery there were only 14/74 (19%) patients.

Conclusion: In regard to the brain hemisphere distal to the ICA stenosis, our study revealed a significant improvement of brain perfusion after EA. Brain perfusion was stable over an interval of 12 months post-surgery. By EA, especially the perfusion reserve increased, as shown by a normal acetazolamide test. Hence, Xenon-133-rCBF could be shown to be an important method in the evaluation of the indication for surgery and of the result of it. In the intra-individual follow-up after EA, rCBF was able to identify hypoperfusion and may help decide, whether re-angiography is necessary or not.