Clinical significance of hemodynamic cerebral ischemia on cognitive function in carotid artery stenosis: a prospective study before and after revascularization.

BACKGROUND: Carotid stenosis is known to have negative impacts on cognitive function. However, it is still unclear through which mechanisms cognitive function is impaired in patients with carotid stenosis. This study was aimed to clarify the impact of cerebral hemodynamics on cognitive function in carotid stenosis. METHODS: This prospective study included totally 109 patients with carotid stenosis who underwent carotid endarterectomy (CEA) or carotid artery stenting (CAS). Using N-isopropyl-p-[123I]-iodoamphetamine SPECT, cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to acetazolamide were quantitatively measured in all patients before and after CEA/CAS. Based on preoperative data, the patients were categorized into three groups: Type 1 (CBF ≥32 mL/min/100 g, CVR ≥10%), Type 2 (CBF ≥32 mL/min/100 g and CVR <10%), and Type 3 (CBF <32 mL/min/100 g and CVR <10%). White matter lesions were categorized according to Wahlund grading. Cognitive function was evaluated with Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) before and 3 months after CEA/CAS. RESULTS: Before CEA/CAS, total RBANS score was significant lower than the age-matched controls, 84±14 in Type 1 group (N.=56), 82±12 in Type 2 group (N.=43), and 70±12 in Type 3 group (N.=10). Especially, Type 3 patients had further lower score than Type 1 (P=0.008) and Type 2 (P=0.039) patients. There were no significant differences in white matter lesions among three groups. Total RBANS scores significantly improved at 3 months after CEA/CAS in all three groups, and the difference among them completely disappeared. CONCLUSIONS: These findings strongly suggest that carotid stenosis itself impairs cognitive function and compromised hemodynamic ischemia further declines it. CEA/CAS significantly improve cognitive function. The beneficial effects are most notable in patients with reduced CBF/CVR.

Effect of carotid endarterectomy on cognitive function in patients with asymptomatic carotid artery stenosis.

BACKGROUND: This study was conducted to determine if patients with asymptomatic carotid artery stenosis show cognitive function decline, and if they experience any changes in cognitive function after carotid endarterectomy (CEA). METHOD: Cognitive function was examined in 15 patients (12 males and three females, 70.0 ± 6.5 years) with asymptomatic carotid artery stenosis before and 3 months after CEA. Cognitive function was assessed with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), two subtests of the Wechsler Adult Intelligence Scale-Revised (WAIS-R 2 subtests), and the Japanese version of National Adult Reading Test (JART). The patients' average scores were compared with the normal average by one-sample t-tests, and the before and after scores were compared with paired t-tests. Changes in each patient were calculated from difference before and after CEA using 95 % confidence intervals. RESULTS: Before surgery, patients showed significant cognitive decline in RBANS total scale and immediate memory, language, and attention. At 3 months after CEA, the total scale and the immediate memory were not significantly different from the normal average. The average total scale score, the immediate memory and attention, and the WAIS-R 2 subtests scores were increased after treatment. Changes in each patient were calculated from the scores before and after CEA. At 3 months after CEA, the rate of increase in RBANS scores were 60.0 % of the patients for immediate memory, 26.7 % for visuospatial/constructional, 33.3 % for language and attention, 26.7 % for delayed memory, 47.7 % for total scale and 26.7 % for WAIS-R 2 subtests. Thus, so-called asymptomatic patients exhibit mild cognitive impairment before surgery, but after CEA, patients recover normal memory abilities. CONCLUSIONS: Our findings of mild cognitive dysfunction in asymptomatic patients suggest that they might be symptomatic after all.

Changes in cognitive function during the 1-year period following endarterectomy and stenting of patients with high-grade carotid artery stenosis.

BACKGROUND: In patients with severe carotid artery stenosis, cognitive decline and changes in cognitive function before to after treatment have been noted, though the true effects of treatment in such patients remain unclear. A convenient and repeatable neuropsychological test battery is needed for such patients. METHODS: In 26 patients with severe carotid artery stenosis treated by carotid endarterectomy (CEA) and stenting (CAS), cognitive function was examined before and 1 week, 3 months, 6 months, and 1 year after treatment. RBANS and MMSE were selected as a test battery, and changes in test scores and long-term results of revascularization were evaluated. RESULTS: RBANS was useful and suitable for neuropsychological testing in such patients, and yielded the following results: (1) Patients before treatment had, on average, RBANS scores rated low average, with mild but relatively diffuse cognitive impairment; (2) RBANS scores were increased significantly at 3 months after CEA and CAS, and cognitive improvement was maintained over 1 year; and (3) scores were decreased temporarily at 1 week after CEA, but not after CAS. CONCLUSIONS: Patients with severe carotid artery stenosis exhibited mild decline in cognitive function, which was improved after CEA and CAS. RBANS is a suitable test battery for this type of patient.

Clinical value of constructional skill testing in patients with secondary normal pressure hydrocephalus--two case reports.

Cognitive functions are frequently impaired in patients with normal pressure hydrocephalus (NPH). Two patients with NPH initially had dysfunctional constructional skill but exhibited improvements after shunt surgery. Dysfunction of constructional skill should be added to the important clinical features of NPH. The geometric test can be used as a practical tool for evaluation of parietal lobe function in patients with NPH.

[Cognitive function in patients with severe carotid stenosis--evaluation of RBANS, WAIS-R and NART before treatment of carotid revascularization--].

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.

[A case of carbon monoxide poisoning by explosion of coal mine presenting as visual agnosia: re-evaluation after 40 years].

We re-evaluated a case of carbon monoxide poisoning presenting as visual agnosia who had been injured by explosion of Miike-Mikawa coal mine 40 years ago. In an early stage, his main neuropsychological symptoms were visual agnosia, severe anterograde amnesia, alexia, agraphia, constructional apraxia, left hemispatial neglect and psychic paralysis of gaze, in addition to pyramidal and extra pyramidal signs. At the time of re-evaluation after 40 years, he still showed visual agnosia associated with agraphia and constructional apraxia. Concerning visual agnosia, recognition of the real object was preserved, while recognition of object photographs and picture was impaired. Thus, this case was considered to have picture agnosia as he could not recognize the object by pictorial cues on the second dimensional space. MRI examination revealed low signal intensity lesions and cortical atrophy in the bilateral parieto-occipital lobes on T1-weighted images. Therefore, the bilateral parieto-occipital lesions are likely to be responsible for his picture agnosia.

[A case of representational dysgraphia and object representational disorder with unilateral spatial neglect].

We describe the case of a 48-year-old left-handed woman with unilateral neglect from a brain infarction in the area of the right basal ganglia and temporo-parieto-occipital lobe. When a Kanji character was dictated to her, she wrote only the right side (tukuri) of the character. When copying a picture from the visual image of a left-right asymmetrical object, such as the side view of the dog, she drew the tail and a hind leg immediately but was unable to draw a picture of the dog from the left side. We asked her to imagine going around to the opposite side of the imaginary dog and to draw it from that perspective. She easily drew the left side first, resulting in a left-right inverted picture of what she had previously drawn. She then tried to slowly visualize the missing part of her imagery, and was able to draw only the right tip of the missing part. She could not compose a complete picture of the dog. These findings suggested that the impairment was in the imaging of the left side of a character or object and that this was a case of representational dysgraphia and object representational disorder with unilateral spatial neglect.

Radical "visual capture" observed in a patient with severe visual agnosia.

We report the case of a 79-year-old female with visual agnosia due to brain infarction in the left posterior cerebral artery. She could recognize objects used in daily life rather well by touch (the number of objects correctly identified was 16 out of 20 presented objects), but she could not recognize them as well by vision (6 out of 20). In this case, it was expected that she would recognize them well when permitted to use touch and vision simultaneously. Our patient, however, performed poorly, producing 5 correct answers out of 20 in the Vision-and-Touch condition. It would be natural to think that visual capture functions when vision and touch provide contradictory information on concrete positions and shapes. However, in the present case, it functioned in spite of the visual deficit in recognizing objects. This should be called radical visual capture. By presenting detailed descriptions of her symptoms and neuropsychological and neuroradiological data, we clarify the characteristics of this type of capture.

Reversal of cognitive dysfunction by total removal of a large lateral ventricle meningioma: a case report with neuropsychological assessments.

Although cognitive impairment is one of the major symptoms of ventricular tumors, few studies have reported the details of cognitive impairment before and after their surgical removal. The expected effects on cognitive function should also be considered when choosing a surgical approach. We report the case of a large lateral ventricle meningioma in which cognitive impairment was detected on detailed neuropsychological examinations. The tumor was totally removed through the right superior temporal gyrus. Postoperative neuropsychological assessment revealed the reversal of cognitive impairment. As cognitive impairment is complex and easily overlooked, it is important to precisely assess neuropsychological function in patients with large brain tumors.

Impact of bilateral subthalamic stimulation on motor/cognitive functions in Parkinson's disease.

It is still unclear whether deep brain stimulation targeted to the bilateral subthalamic nucleus (STN-DBS) affects cognitive function in Parkinson's disease (PD). This prospective study was aimed to systemically evaluate the impact of bilateral STN-DBS on motor and cognitive functions in patients with PD. This study included totally 11 Japanese patients with medically intolerant PD. Neurological and cognitive status was precisely evaluated before and 1 year after bilateral STN-DBS, using unified Parkinson's disease rating scale (UPDRS), levodopa equivalent doses, mini-mental state examination (MMSE), Japanese adult reading test (JART), repeatable battery for the assessment of neuropsychological status (RBANS), and Wechsler adult intelligence scale-revised (WAIS-R). Preoperative RBANS and WAIS-R identified cognitive dysfunction that could not be detected by MMSE and JART. Before surgery, PD patients had significantly impaired immediate memory and attention. Motor function significantly improved 1 year after bilateral STN-DBS. Bilateral STN-DBS did not affect any score on cognitive examinations. However, postoperative improvements of total score on RBANS and performance intelligence quotient (PIQ) scores on WAIS-R were closely related to those of UPDRS part III off (R(2) = 0.61, P < 0.01; R(2) = 0.39, P < 0.05, respectively). These findings strongly suggest that bilateral STN-DBS may significantly improve cognitive function in a certain subgroup of patients whose therapeutic effects on motor function are prominent.

Anomia for people's names after left anterior temporal lobe resection--case report.

A 47-year-old man was admitted to our hospital with an intrinsic brain tumor in the left anterior temporal lobe. Preoperative sodium thiopental test demonstrated left hemispheric dominance. Awake craniotomy was performed for dominant-hemispheric tumor resection using language mapping to identify the stimulation-induced positive language area. The tasks of object naming and repetition were used, along with specific tests for famous people's names. The language area was detected on the superior temporal gyrus and preserved. Following surgery, this patient was unable to retrieve the names of famous individuals (i.e. anomia for people's name) despite preservation of semantic knowledge for those individuals. This anomia for people's names showed no improvement at all for a period of 15 months. This case report and other sporadic cases with this type of deficit reveal the left anterior temporal lobe is an important brain area for retrieving people's names.

Neuropsychological changes after endoscopic third ventriculostomy for long-standing overt ventriculomegaly in adults. Case report.

A 39-year-old woman presented with long-standing overt ventriculomegaly in adults (LOVA) manifesting as gradually worsening headache. Past history included treatment for myeloschisis at birth. Intelligence quotient (IQ) was 115 and preoperative psychological assessment using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) showed normal scores in all domains. However, scores for constructional ability were slightly low. Computed tomography revealed severe ventriculomegaly involving the lateral and third ventricles, and magnetic resonance imaging showed aqueductal stenosis. Endoscopic third ventriculostomy was performed under a diagnosis of LOVA. Postoperatively, the headache resolved and the RBANS showed improvements in memory and constructional ability. Detailed evaluation of cognitive function provides a good indicator in the treatment of hydrocephalus with normal IQ.