Neuropsychological and magnetic resonance imaging abnormalities associated with a plasmacytoma of the frontal dura: a case report.

OBJECTIVE: The goal of this investigation was to describe the neuropsychological and magnetic resonance imaging (MRI) findings in a patient with an extramedullary plasmacytoma that extensively infiltrated the cerebral dura, especially over the frontal region. BACKGROUND: Extramedullary plasmacytomas are rare tumors that have been reported to involve the dura matter in only a small number of cases. In most of the reported occurrences, the dura plasmacytomas were successfully treated with a combination of surgery and irradiation, without prominent cognitive sequelae. METHOD: MRI of the brain and neuropsychological tests were conducted approximately 13 months after the patient underwent radiotherapy. In addition, measures of frontal lobe personality characteristics were obtained before and after radiotherapy. RESULTS: MRI findings revealed extensive enhancement around the anterior frontal lobes and prominent involvement of the anterior longitudinal fissure. Results from neuropsychological testing indicated mild to moderately impaired performance on tests of working memory, complex attention, and cognitive flexibility. Further, the patient reported experiencing personality changes consistent with frontal lobe dysfunction as part of the initial symptoms of the disease, which remained unchanged after treatment. CONCLUSIONS: Our findings are the first to describe cognitive sequelae of dural plasmacytomas. In addition, results from this case study reveal that plasmacytomas of the frontal dura produce personality changes similar to those observed in patients with significant frontal lobe injury. Finally, plasmacytomas that significantly infiltrate the frontal lobes may be insensitive to radiotherapy and result in residual cognitive and personality abnormalities.

A single-photon emission computed tomography imaging study of driving impairment in patients with Alzheimer's disease.

Single-photon emission computed tomography (SPECT) was used in this study to examine the neurophysiologic basis of driving impairment in 79 subjects with dementia. Driving impairment, as measured by caregiver ratings, was significantly related to regional reduction of right hemisphere cortical perfusion on SPECT, particularly in the temporo-occipital area. With increased severity of driving impairment, frontal cortical perfusion was also reduced. Clock drawing was more significantly related to driving impairment than the Mini-Mental State Examination (MMSE). Driving impairment in Alzheimer's disease is related to changes in cortical function which vary according to the severity of the disease. Cognitive tests of visuoperceptual and executive functions may be more useful screening tools for identifying those at greatest risk for driving problems than examinations like the MMSE that are weighted toward left-hemisphere-based verbal tasks.

The relation of neuropsychological measures to levels of cognitive functioning in elderly individuals: a discriminant analysis approach.

This study addresses the question of which tests in a comprehensive neuropsychologicaI test battery best discriminate normal, mildly, and moderate to severely cognitiveIy impaired older participants. Sixty-six geriatric participants were administered a battery of neuropsychological tests as part of an outpatient geriatric clinic evaluation. A discriminant analysis procedure using a consensus rating of global cognitive impairment as the grouping variable was employed to analyze the data. From 15 neuropsychological test measures, five representing the domains of learning and memory, visuospatial and executive functioning were identified as the best predictors of level of cognitive impairment. Findings demonstrate the utility of discriminant function analysis (DFA) procedures for developing reduced-length cognitive batteries that accurately classify participants in terms of levels of cognitive impairment and identify mild dysfunction in participants at risk of cognitive impairment. Further cross-validation studies are needed to confirm the utility of these more circumscribed batteries.

Order effects in the administration of a forced-choice procedure for detection of malingering in disability claimants' evaluations.

100 disability claimants of the Social Security Administration referred for neuropsychological evaluation and 40 undergraduate college students asked to simulate brain damage were administered a measure for the detection of malingering, an abbreviated version of the Hiscock Forced-choice Procedure, and other neuropsychological tests. Half of each group was administered the Hiscock Procedure at the beginning of the battery; the other half was administered this test last. For both groups, the results indicated poorer performance on the earlier administration of the abbreviated Hiscock Forced-choice Procedure. Formal measures for detection of malingering should be an integral and early part of any neuropsychological evaluation in which the subject has a financial incentive to perform poorly.

Cognitive effects of flumazenil in patients with Alzheimer's disease.

Intravenous flumazenil was administered to two patients with probable Alzheimer's disease. Neuropsychological tests were administered at baseline, immediately after drug administration, and at washout 3 hours later. Cognitive function was observed to decline in both patients with eventual return to baseline, which indicates an adverse effect of flumazenil. Tests of vigilance were most severely affected, which may have been related to an inverse agonistic effect of flumazenil in producing symptoms of anxiety.

Impaired awareness of deficits in Alzheimer disease.

This study examined the relation between awareness of memory and functional decline and cognitive function in patients with Alzheimer disease (AD). Twenty-six patients with early AD and 16 nondemented elderly controls were studied. Awareness of deficits was determined by using (a) a discrepancy score between subject's and caregiver's ratings on a memory questionnaire, (b) a discrepancy score between subject's and caregiver's ratings on an activities-of-daily-living scale, and (c) a clinical rating of dementia awareness for patients. Whereas self-ratings of memory and activities of daily living were not significantly different between AD patients and controls, these two measures differed significantly when AD patients' ratings were compared with those of their caregivers. Measures of awareness of deficits correlated with one another and were primarily associated with performance on tests of executive and visuospatial functions but not with depression. Early AD is characterized by a failure of self-monitoring. Deficits in self-monitoring have been proposed to occur after damage to the frontal lobes and other cerebral areas. Impaired awareness of memory and functional deficits in AD is related to cognitive impairments, which may involve frontal and right hemisphere connections.

Mental status and memory assessment as predictors of dementia.

Mental status instruments that have been used in assessing the cognitive status of elderly adults have focused primarily on orientation and remote memory. In this study the Extended Mental Status Questionnaire (EMSQ) and the Philadelphia Geriatric Center (PGC) Delayed Memory Test were found to be the best combined predictors of clinical judgment of senile dementia among a multidisciplinary set of variables. The EMSQ differentiated patients with moderate/severe dementia from patients classified as non- or mildly demented but incorrectly classified all mildly demented patients. With the addition of the PGC Delayed Memory Test, 75% of the mildly demented patients were classified correctly. The PGC Delayed Memory Test, therefore, appears to be useful in identifying patients in the early stages of cognitive decline.

Geriatric center's environment fosters interaction.

Because environment affects disabled persons more than nondisabled ones, institutions should offer more than cleanliness, efficiency, and care of residents' physical needs. The Weiss Institute, using bright colors, warm wood, natrual light, open spaces, possessions from home, and a floor plan that encourages spontaneous interaction, seeks to maximize residents' well-being, competence, and self-esteem and to meet both staff and residents' social and emotional needs.