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Biomedical subjects

B F Boeve

Publications and source records attributed to B F Boeve.

49 records · Page 3Linked to original sources
PubMed1999

Prediction of AD with MRI-based hippocampal volume in mild cognitive impairment.

OBJECTIVE: To test the hypothesis that MRI-based measurements of hippocampal volume are related to the risk of future conversion to Alzheimer's disease (AD) in older patients with a mild cognitive impairment (MCI). BACKGROUND: Patients who develop AD pass through a transitional state, which can be characterized as MCI. In some patients, however, MCI is a more benign condition, which may not progress to AD or may do so slowly. PATIENTS: Eighty consecutive patients who met criteria for the diagnosis of MCI were recruited from the Mayo Clinic Alzheimer's Disease Center/Alzheimer's Disease Patient Registry. METHODS: At entry into the study, each patient received an MRI examination of the head, from which the volumes of both hippocampi were measured. Patients were followed longitudinally with approximately annual clinical/cognitive assessments. The primary endpoint was the crossover of individual MCI patients to the clinical diagnosis of AD during longitudinal clinical follow-up. RESULTS: During the period of longitudinal observation, which averaged 32.6 months, 27 of the 80 MCI patients became demented. Hippocampal atrophy at baseline was associated with crossover from MCI to AD (relative risk [RR], 0.69, p = 0.015). When hippocampal volume was entered into bivariate models-using age, postmenopausal estrogen replacement, standard neuropsychological tests, apolipoprotein E (APOE) genotype, history of ischemic heart disease, and hypertension-the RRs were not substantially different from that found univariately, and the associations between hippocampal volume and crossover remained significant. CONCLUSION: In older patients with MCI, hippocampal atrophy determined by premorbid MRI-based volume measurements is predictive of subsequent conversion to AD.

Aged↗
PubMed1999

REM sleep behavior disorder and dementia: cognitive differences when compared with AD.

OBJECTIVE: To determine whether the dementia associated with REM sleep behavior disorder (RBD) differs from Alzheimer's disease (AD) and, if so, whether differences in cognitive performance between RBD/dementia and AD resemble reported differences between dementia with Lewy bodies (DLB) and AD. METHODS: This retrospective study compares neurocognitive performance between 31 patients with degenerative dementia and polysomnography-confirmed RBD and 31 patients without brainstem Lewy body pathology who met Consortium to Establish a Registry for Alzheimer's Disease (CERAD) clinical and neuropathologic criteria for AD. The patient groups did not differ in dementia severity (based on Global Deterioration Scale score) or duration. RESULTS: RBD preceded or coincided with the onset of cognitive decline in 94% of the patients. All but one patient with RBD/dementia had one or more of the following clinical features of DLB: visual hallucinations, extrapyramidal signs, or fluctuating cognition/alertness. The data revealed significantly worse performance on attention, perceptual organization, visual memory, and letter fluency for the RBD/dementia group, whereas the AD group showed significantly worse performance on confrontation naming and verbal memory. CONCLUSIONS: Patients with RBD and degenerative dementia demonstrate a significantly different pattern of cognitive performance from patients with AD. Most of the patients in the RBD/dementia sample also meet criteria for possible or probable DLB, and the pattern of cognitive differences from AD is similar to reported comparisons between DLB and AD. The cognitive and clinical data provide evidence to suggest that the dementia associated with RBD may represent DLB.

Aged↗
PubMed1999

A kinematic study of progressive apraxia with and without dementia.

BACKGROUND: Prehension is an ideationally simple, cued movement requiring proximal (transport) and distal (manipulation) limb control. Patients with this syndrome of progressive apraxia are unable to perform many activities of daily living that require prehension. There is little known about how this syndrome kinematically disrupts such movements or whether concurrent dementia might play a critical role. OBJECTIVES: Using prehension as a paradigm for an ideationally simple, cued functional movement, we sought to (1) characterize the kinematic features of progressive apraxia in general, and (2) contrast the kinematic differences between apraxic patients with and without dementia. METHODS: Eight patients with the syndrome of progressive apraxia (including five without dementia, one of whom had autopsy-confirmed corticobasal ganglionic degeneration, and three with dementia, one of whom had autopsy-confirmed Alzheimer's disease) were compared with eight age-matched normal control subjects on a prehension task using an Optotrak camera system. RESULTS: Compared with control subjects, apraxic subjects had slowed reaction time, slowed transport and manipulation kinematics, greater lateral deviation from the linear prehension trajectory, greater intermanual asymmetry, motor programming disturbances, and mild transport-manipulation uncoupling. There were minor differences between the apraxia subgroups such as greater intermanual differences and impaired grip aperture velocity in the nondemented group, and overall slower movement in the demented group. CONCLUSIONS: There are major kinematic differences between apraxic and control subjects on a prehension task. The differences between clinical-pathologic subgroups are more subtle, and the movement disorder itself rather than concurrent dementia is the greatest determinant of motor disability.

Aged↗
PubMed1999

Testing normal older people three or four times at 1- to 2-year intervals: defining normal variance.

Normative data were presented that defined the upper and lower standards for deciding if cognitive abilities show reliable change over 2 or more testing occasions when retesting occurs at 1- to 2-year intervals. The Mayo Cognitive Factor Scores (MCFS; G. E. Smith et al., 1994) were analyzed because they permit the quantitation of overall functioning in 5 clinically important cognitive domains: established verbal knowledge, nonverbal reasoning, attention and concentration, new learning, and delayed memory. To the authors' knowledge, this is the first report of both group-level and individual-level data analyses derived from a respectably sized sample of normal persons who have been tested 3 or more times at clinically common test-retest intervals.

Aged↗
PubMed1998

Clinical presentation and pharmacological therapy in corticobasal degeneration.

BACKGROUND: To date, to our knowledge, there is no systematic presentation of treatment outcome in large series of patients clinically diagnosed as having corticobasal degeneration. OBJECTIVE: To evaluate the clinical presentation and treatment outcome of patients clinically diagnosed as having corticobasal degeneration. SUBJECTS: We gathered case patients seen in 8 major movement disorder clinics during the last 5 years who were diagnosed as having corticobasal ganglionic degeneration. METHODS: Using a chart review method, we recorded the clinical presentation, medications used, response to medications, and adverse effects. RESULTS: A total of 147 case patients were reviewed, 7 were autopsy proven. Parkinsonian features were present in all, other movement disorders in 89%, and higher cortical dysfunction in 93%. The most common parkinsonian sign was rigidity (92%), followed by bradykinesia (80%), gait disorder (80%), and tremor (55%). Other movement disorders were dystonia in 71% and myoclonus in 55%. Higher cortical dysfunction included dyspraxia (82%), alien limb (42%), cortical sensory loss (33%), and dementia (25%). Ninety-two percent of the case patients received dopaminergic drugs, which resulted in a beneficial effect for 24%. Parkinsonian signs were the elements improving the most and levodopa was the most effective drug. Benzodiazepines, primarily clonazepam, were administered to 47 case patients, which resulted in improvement of myoclonus in 23% and dystonia in 9%. The most frequent disabling adverse effects of drug trials in these case patients were somnolence (n = 24), gastrointestinal complaints (n = 23), confusion (n = 16), dizziness (n =12), hallucinations (n = 5), and dry mouth (n = 5). CONCLUSIONS: Pharmacological intervention was largely ineffective in the management of corticobasal degeneration, and new treatments are needed for ameliorating the symptoms of this syndrome.

Antiparkinson Agents↗
PubMed1998

Paroxysmal sympathetic storms ("diencephalic seizures") after severe diffuse axonal head injury.

We describe a patient with a severe traumatic head injury who exhibited paroxysmal sympathetic storms, similar to those described in "diencephalic seizures." No epileptiform activity was evident on electroencephalography, and therapeutic levels of anticonvulsants failed to alter the spells; however, use of morphine sulfate abolished them. The features of this and several previously reported cases refute the primary roles of the diencephalon and seizures in this syndrome. Rather, in the setting of already compromised autonomic neuronal integrity, subtle fluctuations in intraventricular pressure or activation of reflexes triggered from muscle mechanoreceptors or chemoreceptors during episodes of hypertonia are more likely. "Paroxysmal sympathetic storms," a more appropriate descriptive term for these phenomena, should be recognized; thus, unnecessary diagnostic evaluations can be minimized, and appropriate therapy can be initiated.

Adolescent↗
PubMed1998

REM sleep behavior disorder and degenerative dementia: an association likely reflecting Lewy body disease.

BACKGROUND: REM sleep behavior disorder (RBD) has been reported with various neurodegenerative disorders, most frequently in disorders with Lewy body pathology. RBD often precedes the onset of PD, and a recent prospective study showed that 38% of patients with RBD eventually developed PD. METHODS: We identified 37 patients with degenerative dementia and a history of bursts of vigorous movement of the arms and legs with vocalization during sleep and associated with dream recall. Patients with and without two or more signs of parkinsonism were compared. Clinical, laboratory, and neuropsychometric features were analyzed, and criteria for the clinical diagnosis of dementia with Lewy bodies (DLB) were applied to all patients. RESULTS: Thirty-four of the 37 patients were male with mean age at onset of 61.5 years for RBD and 68.1 years for cognitive decline. RBD commenced before or concurrently with dementia in all patients but two. Parkinsonism (two or more signs) occurred in 54% of the sample (20/37), with a mean age at onset of 69.1 years. Polysomnography (PSG) confirmed RBD in all patients studied. Neuropsychological testing demonstrated impaired perceptual-organizational skills, verbal fluency, and marked constructional dyspraxia in more than one-half the patients. There were no statistically significant differences in the frequency of clinical features or in neuropsychological performance between patients with and without parkinsonism. Thirty-four patients (92%) met criteria for clinically possible or probable DLB. Three patients were autopsied; all had limbic with or without neocortical Lewy bodies. CONCLUSIONS: We report a group of predominantly male patients with a characteristic association of RBD and degenerative dementia. The clinical and neuropsychometric features of the groups of patients with and without parkinsonism are similar. We hypothesize that the underlying pathology in these patients is DLB.

Aged↗
PubMed1997

Persistent cauda equina syndrome following bilateral aortoiliac dissection as a complication of cardiac angiography.

Cardiac angiography is accepted as an invasive yet safe procedure with well-characterized complications. We present a complication heretofore not described to our knowledge, in which a patient experienced the cauda equina syndrome following bilateral aortoiliac dissection during cardiac angiography. Similarities are noted between this complication and those documented in abdominal aortic aneurysm repair surgery.

Aged↗
PubMed1996

Dysarthria and apraxia of speech associated with FK-506 (tacrolimus).

The immunosuppressive agent FK-506 (tacrolimus) is one of the agents most commonly used to prevent rejection after liver transplantation. Neurologic toxicity related to FK-506 has been reported, including speech disorders; however, a detailed analysis of the speech disorder associated with use of FK-506 has not been presented. Herein we describe a patient who exhibited mutism, then severe apraxia of speech with a concomitant hypokinetic, spastic, and ataxic dysarthria after administration of FK-506. His residual mixed dysarthria, without radiographic evidence of a structural lesion, suggests dysfunction of one or more neurochemical systems. The pathophysiologic mechanisms underlying this intriguing entity remain obscure.

Apraxias↗
PubMed1995

Bilateral temporal lobe MRI changes in uncomplicated hypoglycemic coma.

We report bilateral temporal lobe MRI findings in a patient following an episode of prolonged hypoglycemia uncomplicated by coexisting anoxia, hypotension, acidosis, drug intoxication, infection, or status epilepticus. The MRI findings are discussed in relation to the experimental and human data on hypoglycemic neuronal injury.

Adult↗
PubMed1994

Electrocardiographic and echocardiographic changes associated with malignant catatonia.

We describe a case of malignant catatonia manifested by catatonic symptoms, fever, hemodynamic instability, and acute neurologic decline that was associated with electrocardiographic and echocardiographic abnormalities similar to those noted in patients with other central nervous system processes. The patient's electrocardiographic and echocardiographic abnormalities resolved after successful electroconvulsive therapy for the underlying neuropsychiatric disorder. The theoretic, physiologic, and clinical significances of this case are discussed.

Aged↗
PubMed1991

Magnetic resonance imaging in the evaluation of knee injuries.

To better define the role of magnetic resonance imaging (MRI) in the evaluation of knee injuries, we analyzed 10 recently published articles comparing MRI and arthroscopy in the detection of meniscal and anterior cruciate ligament tears. Sensitivity (SN), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) for medial meniscus (MM) tears, lateral meniscus (LM) tears, and anterior cruciate ligament (ACL) tears were either obtained or calculated from data contained in each article. The medians of measurements for MM tears were 97% SN, 89% SP, 88% PPV, and 96% NPV. Measurement medians for LM tears were 85% SN, 94% SP, 86% PPV, and 95% NPV. ACL tear measurement medians were 100% SN, 96% SP, 80% PPV, and 98% NPV. High NPVs were found in several studies, many of which were 100%. The high NPV of MR imaging suggests that diagnostic arthroscopic surgery is not necessary in the evaluation of patients with negative MRI studies. The superior sensitivity of MRI in detecting frank posterior horn tears, intrasubstance meniscal tears, and significant incidental findings also suggests that screening MRI scans can facilitate preoperative planning.

Arthroscopy↗