Purpose: To evaluate the cognitive function in preoperative patients with severe carotid stenosis.
Patients and method: Twenty-five patients with severe carotid stenosis were examined on their cognitive function by RBANS (Japanese version), WAIS-R (Japanese version), and NART (Japanese version) before treatment of carotid revascularization (endarterectomy or stenting). They had full activities of daily living without any hemiparesis, aphasia, agnosia, and apraxia at the time of the examinations.
Results: Mean intelligent quotient (IQ) measured by WAIS-R and NART was 104.0 +/- 10.7 and 101.3 +/- 13.4, (ns) respectively. Mean total scale of RBANS was 90.0 +/- 13.4, which was significantly lower than both the results of WAIS-R and NART. A mean value of each RBANS index was 91.3 +/- 11.7 in immediate memory, 102.0 +/- 18.2 in visuospatial/constructional, 93.2 +/- 8.7 in language, 84.6 +/- 14.7 in attention, and 92.1 +/- 14.4 in delayed memory. RBANS index significantly declined in immediate memory, language, attention and delayed memory than visuospatial/constructional.
Conclusions: Qualitative evaluation was available in RBANS, WAIS-R, and NART, which enabled the investigators to make a precise comparison between these methods. WAIS-R and NART showed a comparatively preserved function and were presumed to be useful for the evaluation of the baseline of cognitive function in preoperative patients. RBANS demonstrated a slight decrease in memory and attention in those patients and was expected to be useful to detect the cognitive dysfunction when compared with WAIS-R and NART.