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Biomedical subjects

D Eidelberg

Publications and source records attributed to D Eidelberg.

At least 55 records · Page 3Linked to original sources
PubMed1998

Asymmetric predominantly ipsilateral blepharospasm and contralateral parkinsonism in an elderly patient with a right mesencephalic cyst.

A 66-year-old woman presented with a 3-year history of predominantly right-sided blepharospasm and a 1-year history of progressive predominantly left-sided hemiparkinsonism manifested by a left upper extremity resting tremor and left-sided bradykinesia. Magnetic resonance imaging of the brain revealed a large right mesencephalic cyst with mass effect. Positron emission tomography revealed bilateral striatal hypometabolism consistent with nigrostriatal dopaminergic dysfunction. The association of predominantly ipsilateral blepharospasm and predominantly contralateral hemiparkinsonism is very rare, and its association with a posterior fossa space-occupying lesion has been reported only once. This is the second report of such an association and the first description of adult-onset symptomatology.

Aged↗
PubMed1998

Differential diagnosis of parkinsonism with [18F]fluorodeoxyglucose and PET.

The clinical differentiation between typical idiopathic Parkinson's disease (IPD) and atypical parkinsonian disorders (APD) is complicated by the presence of signs and symptoms common to both forms of parkinsonism. Metabolic brain imaging with [18F]fluorodeoxyglucose (FDG) and positron emission tomography (PET) may be a useful adjunct in differentiating APD from IPD. To explore this possibility, we studied 48 parkinsonian patients suspected as having possible APD because of a deteriorating response to dopaminergic treatment, the development of autonomic dysfunction, or both. A group of 56 patients with likely IPD served as control subjects. We used quantitative FDG/PET to measure regional rates of cerebral glucose use in IPD and APD patients. We used discriminant analysis to categorize IPD and APD patients based on their regional metabolic data. We found that a linear combination of caudate, lentiform, and thalamic values accurately discriminated APD from IPD patients (p < 0.0001). Significant metabolic abnormalities were present in the striatum and the thalamus of 36 of 48 (75%) APD patients. Our findings show that measurements of regional glucose metabolism can be used to discriminate patients with suspected APD from their counterparts with classic IPD. FDG/PET may be a useful adjunct to the clinical examination in the differential diagnosis of parkinsonism.

Aged↗
PubMed1998

Cognitive functioning after pallidotomy for refractory Parkinson's disease.

BACKGROUND: Earlier approaches to pallidotomy for refractory Parkinson's disease had significant complication rates. More recent approaches show fewer complications, but the effect of pallidotomy on cognition is unclear. The current study was conducted to examine the neuropsychological effects of unilateral pallidotomy. METHODS: Neuropsychological testing was performed on patients with medically refractory, predominantly unilateral Parkinson's disease at baseline and after unilateral ventral pallidotomy (n=28) or after an equivalent period without surgery in control patients (n=10). RESULTS: Pallidotomy patients showed no significant changes from baseline to retesting relative to the control group for any measure. Across all of the tests administered, only five of the surgery patients showed a significant decline, and of these five none declined on more than one test. Depression did not relate to preoperative or postoperative cognition. The pallidotomy group showed a significant improvement in motor functioning and activities of daily living whereas the control group did not. These measures were not associated with the neuropsychological test scores at baseline or retest. CONCLUSIONS: Stereotactic unilateral ventral pallidotomy does not seem to produce dramatic cognitive declines in most patients.

Activities of Daily Living↗
PubMed1998

Cerebral glucose metabolism in women with panic disorder.

OBJECTIVE: This study was undertaken to clarify earlier inconsistent findings in brain metabolic topography in panic disorder patients at rest. METHOD: Positron emission tomography (PET) with [18F]fluorodeoxyglucose was used to determine cerebral metabolic activity in six female patients with a DSM-III-R diagnosis of panic disorder and in six healthy female volunteers. All patients with panic disorder were medication free and were sensitive to lactate infusion. RESULTS: A significant increase in glucose metabolism was found in the left hippocampus and parahippocampal area of the panic disorder subjects in comparison with that found in the healthy subjects. In addition, a significant decrease in metabolism was found in the right inferior parietal and right superior temporal brain regions of the panic disorder subjects in comparison with that of the normal subjects. There was no significant correlation between scores for the severity of panic disorder or for the severity of lactate-induced panic attack and the quantified PET abnormality. CONCLUSIONS: These data provide further support for the hypothesis of an abnormal brain metabolism in the hippocampal and parahippocampal area in individuals with panic disorder and also suggest other areas of aberrant brain metabolism in this disorder.

Adult↗
PubMed1998

The metabolic anatomy of tremor in Parkinson's disease.

OBJECTIVE: To identify regional metabolic brain networks related specifically to the presence of tremor in PD. BACKGROUND: The pathophysiology of parkinsonian tremor is unknown. Because tremor in PD occurs mainly in repose, we used resting state PET with 18F-fluorodeoxyglucose (FDG) to identify specific metabolic brain networks associated with this clinical manifestation. METHODS: We studied two discrete groups of eight PD patients with and without tremor using FDG/PET. Both patient groups were matched for gender, age, and Unified Parkinson Disease Rating Scale ratings for akinesia and rigidity. Ten normal volunteer subjects served as controls. RESULTS: Network analysis with the Scaled Subprofile Model was performed in two steps. 1) We computed the expression of the PD-related pattern (PDRP) identified by us previously in each of the PD patients and control subjects. Although PDRP subject scores were abnormally elevated in the combined PD cohort (p < 0.005), these values did not differ in the PD patient groups with and without tremor (p = 0.36). 2) We used SSM to analyze the data from the combined PD cohort comprising both patient groups. We found that PD patients with tremor were characterized by increased expression of a metabolic network comprising the thalamus, pons, and premotor cortical regions. Subject scores for this pattern were elevated in the tremor group compared with the atremulous patient group and the normal control group (p < 0.005). CONCLUSIONS: The findings suggest that PD patients with tremor are characterized by distinct increases in the functional activity of thalamo-motor cortical projections. Modulation of this functional anatomic pathway is likely to be the mechanism for successful interventions for the relief of parkinsonian tremor.

Aged↗
PubMed1998

Nervous system dysfunction in Waldenström's macroglobulinemia: response to treatment.

A patient presented with a peripheral neuropathy and was found to have Waldenstrom's macroglobulinemia with high serum titers of antibodies to myelin-associated glycoprotein. He developed parkinsonism that was poorly responsive to levodopa. He failed conventional therapy and was treated with autologous bone marrow transplantation, which resulted in improvement of the neuropathy but not his parkinsonism. Critical cytoreduction in the B-cell clone may be necessary for improvement of the neuropathy of Waldenstrom's macroglobulinemia.

Antibodies, Monoclonal↗
PubMed1998

Brain lactate and N-acetylaspartate in pediatric AIDS encephalopathy.

Two children with acquired immunodeficiency syndrome (AIDS) and progressive encephalopathy underwent MR spectroscopy before and after antiretroviral therapy. Initial MR spectroscopy of the basal ganglia region showed decreased N-acetylaspartate (NAA)/creatine (Cr) and a lactate peak. After therapy, there was improvement in NAA/Cr and an absence of the abnormal lactate peak. We suggest that decreased NAA/Cr in AIDS is reversible, that brain lactate might correlate with inflammation, and that MR spectroscopy can be useful in treatment trials.

AIDS Dementia Complex↗
PubMed1998

Dopamine transporter imaging with fluorine-18-FPCIT and PET.

UNLABELLED: Fluorinated N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane (FPCIT) has been synthesized as a dopamine transporter ligand for PET studies. We evaluated the regional brain uptake and the plasma metabolism of [18F]-FPCIT. METHODS: PET studies were conducted on 7 normal subjects and on 10 patients with Parkinson's disease. After the [18F]-FPCIT injection (4.4+/-1.8 mCi), dynamic scans were acquired over 100 min. Plasma metabolite analysis was performed using high-performance liquid chromatography (HPLC). RESULTS: Plasma HPLC revealed two peaks corresponding to unmetabolized [18F]-FPCIT and a polar metabolite. The fraction of the parent compound decreased rapidly to 25% at 25 min. Fluorine-18-FPCIT showed a striatum-to-occipital ratio (SOR) of 3.5 at 90 min postinjection. The ratio of striatal-to-occipital distribution volume (DVR) was calculated directly by using a mean tissue-to-plasma efflux constant for occipital cortex obtained in 10 subjects (ki=0.037 min(-1)). DVR measures determined with and without plasma input function were correlated (r=0.98, p < 0.0001). In normal subjects, a significant age-related decline of DVR was observed both for caudate and putamen, corresponding to a 7.7% and 6.4% decline per decade, respectively (r > 0.85, p < 0.01). Both DVR and SOR correctly classified early-stage Parkinson's disease patients with comparable accuracy (p < 0.0001). Age-corrected DVR values correlated negatively with the Uniform Parkinson's Disease Rating Scale composite motor ratings (r=0.66, p < 0.05). CONCLUSION: The tracer characteristics are compatible with a high-affinity, reversible ligand. FPCIT/PET demonstrated age-related decline in dopamine transporter binding in normal subjects as well as significant reductions in patients with idiopathic Parkinson's disease, which correlates with the disease severity.

Aged↗
PubMed1997

Efficacy of bilateral pallidotomy.

Unilateral pallidotomy is a safe and effective treatment for medically refractory bradykinetic Parkinson's disease, especially in those patients with levodopa-induced dyskinesia and severe on-off fluctuations. The efficacy of bilateral pallidotomy is less certain. The authors completed 11 of 12 attempted bilateral pallidotomies among 150 patients undergoing pallidotomy at New York University. In all but one patient, the pallidotomies were separated by at least 9 months. Patients were selected for bilateral pallidotomy if they exhibited bilateral rigidity, bradykinesia, or levodopa-induced dyskinesia prior to treatment or if they exhibited disease progression contralateral to their previously treated side. The Unified Parkinson's Disease Rating Scale (UPDRS) and timed upper-extremity tasks of the Core Assessment Protocol for Intracerebral Transplantation (CAPIT) were administered to all 12 patients in the "off" state (12 hours without receiving medications) preoperatively and again at 6 and 12 months after each procedure. The median UPDRS and contralateral CAPIT scores improved 60% following the initial procedure (p = 0.008, Wilcoxon rank sums test). The second pallidotomy generated only an additional 10% improvement in the UPDRS and CAPIT scores ipsilateral to the original procedure (p = 0.05). Worsened speech was observed in two cases. In the 12th case, total speech arrest was noted during test stimulation. Speech returned within minutes after stimulation was halted. Lesioning was not performed. These results indicate that bilateral pallidotomy has a narrow therapeutic window. Motor improvement ipsilateral to the first lesion leaves little room for further improvement from the second lesion and the risk of speech deficit is greatly enhanced. Chronic pallidal stimulation contralateral to a previously successful pallidotomy may prove to be a safer alternative for the subset of patients who require bilateral procedures.

Journal Article↗
PubMed1997

Temporal lobe epilepsy: correlation of proton magnetic resonance spectroscopy and 18F-fluorodeoxyglucose positron emission tomography.

Proton magnetic resonance spectroscopy (MRS) has demonstrated reduction of N-acetylaspartate (NAA) in the epileptogenic temporal lobe. However, the correlation of NAA reduction with cerebral metabolic abnormalities is unknown in temporal lobe epilepsy (TLE). Proton MRS and 18F-fluorodeoxyglucose positron emission tomography (FDG/PET) were used to study 12 unilateral TLE patients with medically intractable seizures and 26 age-matched healthy volunteers. The epileptogenic temporal lobe of each patient was determined by both electroencephalography and FDG/PET. The NAA/choline-plus-creatine (NAA/(Cho+Cr)) ratio correlated significantly with the interictal glucose metabolism (r = 0.54, P < 0.01) in 12 TLE patients. The mean NAA/(Cho+Cr) ratio in the epileptogenic temporal lobe was significantly less than that in the contralateral side (P < 0.01), and less than that in normal control temporal lobes (P < 0.0001). These results suggest that quantitative MRS abnormalities reflect underlying metabolic pathology in TLE.

Adult↗
PubMed1997

Selection criteria for unilateral posteroventral pallidotomy.

In an attempt to refine the indications for posteroventral pallidotomy (PVP) the authors instituted strict selection criteria which are based on the experience gained from the first 60 pallidotomy patients treated at their institution. In addition to clinical evaluation, all pallidotomy candidates undergo neuropsychological testing and 18F-fluoro-deoxyglucose utilization positron emission tomography (FDG/PET). The data from which these criteria were developed are presented as are early clinical results. The authors demonstrate that these criteria enhance the efficacy of the procedure by assuring therapeutic response and reducing the incidence of post-operative dementia. Their indications and contraindications for pallidotomy are discussed.

Antiparkinson Agents↗
PubMed1997

Divergent expression of regional metabolic topographies in Parkinson's disease and normal ageing.

We have used [18F]fluorodeoxyglucose (FDG) with PET to identify regional metabolic covariance patterns associated with Parkinson's disease and normal ageing. In this study we utilized these patterns as metabolic markers to assess the relative roles of these processes in the progression of parkinsonism. We studied 37 Parkinson's disease patients and 20 normal volunteer subjects with FDG/PET to calculate regional metabolic rates for glucose. We applied the Parkinson's disease and normal ageing regional covariance patterns separately to these data to compute the expression of both these markers in each subject on an individual case basis. The measured expression of the normal ageing pattern provided an estimate of subject age, based entirely upon the FDG/PET data. The normalized difference between this metabolic estimate and chronological age (delta) was then computed, where delta = (metabolic age - real age)/(real age). We found that delta values were negative and significantly reduced in the Parkinson's disease cohort compared with normal subjects (P < 0.005) indicating a consistent underestimation of chronological age by FDG/PET in parkinsonism. In the Parkinson's disease group, delta correlated negatively with disease duration (r = -0.38, P < 0.04); extrapolation of this linear relationship to delta = 0 yielded an estimate of the mean preclinical period of 4.5 years. These findings suggest that the Parkinson's disease process is likely to be associated with a progressive disruption of the normal age-metabolism relationship, rather than with an exaggeration of the normal ageing process. Our metabolic data also suggest that the preclinical period in Parkinson's disease is of relatively short duration.

Aging↗
PubMed1997

Metabolic correlates of pallidal neuronal activity in Parkinson's disease.

We have used [18F]fluorodeoxyglucose and PET to identify specific metabolic covariance patterns associated with Parkinson's disease and related disorders previously. Nonetheless, the physiological correlates of these abnormal patterns are unknown. In this study we used PET to measure resting state glucose metabolism in 42 awake unmedicated Parkinson's disease patients prior to unilateral stereotaxic pallidotomy for relief of symptoms. Spontaneous single unit activity of the internal segment of the globus pallidus (GPi) was recorded intraoperatively in the same patients under identical conditions. The first 24 patients (Group A) were scanned on an intermediate resolution tomograph (full width at half maximum, 8 mm); the subsequent 18 patients (Group B) were scanned on a higher resolution tomograph (full width half maximum, 4.2 mm). We found significant positive correlations between GPi firing rates and thalamic glucose metabolism in both patient groups (Group A: r = 0.41, P < 0.05; Group B: r = 0.69, P < 0.005). In Group B, pixel-based analysis disclosed a significant focus of physiological-metabolic correlation involving the ventral thalamus and the GPi (statistical parametric map: P < 0.05, corrected). Regional covariance analysis demonstrated that internal pallidal neuronal activity correlated significantly (r = 0.65, P < 0.005) with the expression of a unique network characterized by covarying pallidothalamic and brainstem metabolic activity. Our findings suggest that the variability in pallidal neuronal firing rates in Parkinson's disease patients is associated with individual differences in the metabolic activity of efferent projection systems.

Aged↗
PubMed1997

The metabolic anatomy of Tourette's syndrome.

The functional brain networks underlying the clinical manifestations of Gilles de la Tourette's syndrome (TS) are currently unknown. To identify these networks, we studied TS patients and normal subjects with 18F-fluorodeoxyglucose (FDG) and PET employing a statistical model of regional metabolic covariation. We studied 10 TS patients (mean age, 41.5 +/- 12.7 years) who were either drug naive or medication free for at least 2 years. Ten normal volunteers (mean age, 42.5 +/- 11.5) served as controls. We used quantitative FDG/PET to calculate global, regional, and normalized rates of glucose metabolism (GMR, rCMRGlc, and rCMRGlc/GMR) in all subjects. The Scaled Subprofile Model (SSM) was used to identify specific patterns of regional metabolic covariation associated with TS. We found that global and regional metabolic rates were normal in TS. SSM analysis identified two TS-related brain networks. One pattern (15.8% variance accounted for, VAF) was characterized by covariate bilateral metabolic increases in lateral premotor and supplementary motor association cortices and in the midbrain. Individual patient expression of this pattern (subject score) was abnormally increased in the TS group (p < 0.01). A second pattern (10.5% VAF) was characterized by covariate decreases in caudate and thalamic metabolism associated with smaller reductions in lentiform and hippocampal metabolic activity. Subject scores for this pattern correlated with Tourette Syndrome Global Scale (TSGS) global ratings (r = 0.85, p < 0.005). We conclude that the metabolic landscape of TS is characterized by a nonspecific pattern of increased motor cortical activity identified in other hyperkinetic disorders. TS is also associated with a specific brain network characterized by a reduction in the activity of limbic basal ganglia-thalamocortical projection systems.

Adult↗