Neuropsychological Changes in Patients with Carotid Stenosis after Carotid Endarterectomy

Abstract

We investigated changes in neuropsychological function in patients with carotid stenosis following carotid endarterectomy (CEA) in relation to cerebral hemodynamics. The subjects were 24 patients who underwent CEA and 17 healthy controls matched by age, educational level, gender and handedness. Cerebral angiography, single-photon emission computed tomography (SPECT) and neuropsychological tests were performed approximately 1 week before and 3 weeks after CEA in all patients. In the patient group, the categories achieved in the new modified Wisconsin Card Sorting Test (WCST) improved significantly after CEA (4.0 ± 2.0; before CEA: 2.3 ± 2.1, p < 0.01). The perseverative errors of Nelson in the WCST improved significantly (before CEA: 9.1 ± 6.9, after CEA: 3.3 ± 3.4, p < 0.01). The difficulty maintaining set in the WCST improved significantly (before CEA: 2.3 ± 1.9, after CEA: 1.3 ± 1.7, p < 0.05). In the control group, none of the test scores showed significant improvement between the first and second tests. Moreover, frontal lobe function improved significantly in those patients with baseline carotid artery diameter of more than 70% of normal, or whose preoperative cerebral perfusion reserve was reduced by less than 15% of a response to acetazolamide. Our results suggest that CEA improves frontal lobe function in patients with severe carotid stenosis or reduced cerebral perfusion reserve.

The Role of Carotid Artery Stenting and Carotid Endarterectomy in Cognitive Performance

“…14 Other studies have shown benefit from improved perfusion after carotid revascularization, particularly in patients with reduced cerebral reserve. 22,29,34,39 However, cognitive deterioration might also occur in the context of cerebral hyperperfusion. 14 From this literature review, it appears that there are more data supporting an effect from flow variation than from microembolism on cognitive performance after carotid revascularization.…”

“…Three studies analyzing flow modification by single photon emission CT found a correlation between flow modification and cognitive improvement in patients with reduced cerebral reserve. 29,34,39 The effect of microembolism was extensively analyzed but contradictorily defined.…”

“…5,17-26,28 -42 The study population varied from 22 to 189. To compare cognitive outcome, 12 studies used single or multiple control groups varying from healthy people (nϭ7), 19,25,29,33,34,41,42 to patients with vascular risk factors (nϭ1), 19 to those with peripheral disease (nϭ2), 20,25 those undergoing orthopedic surgery (nϭ3), 21,30,38 or those undergoing urologic surgery (nϭ1). 28 One study analyzed cognitive outcome exclusively in asymptomatic 19 and 5 in symptomatic carotid stenosis.…”

“…27 A correlation between flow modification by single photon emission CT and cognitive improvement after revascularization has been shown, especially in patients with reduced cerebral reserve. 29,34,39 There were overall 5 studies analyzing CAS without use of CPD. 21,27,47,44,45 In all except one (which showed improved results), 45 no changes in cognition could be found after CAS.…”

Asymptomatic carotid artery stenosis—Medical therapy alone versus medical therapy plus carotid endarterectomy or stenting

“…In addition to the disadvantages of BMT, there is a downside to lack of repair: continued annual risk of stroke in excess of the annual risk after repair, psychologic effects of living with a threatening lesion, and the potential of long-term cognitive deterioration. [44][45][46][47][48] Drawing ridiculous conclusions from skimpy evidence, some have called for a cessation or severe limitation of carotid repair. 4,5,49 It is disingenuous to treat small groups of asymptomatic patients with nonlesions, see that they remain asymptomatic with BMT, and then claim victory.…”