Opsoclonus-induced occipital deactivation with a region-specific distribution.

The cerebral distribution of 2-[18F]fluoro 2-deoxy-D-glucose (FDG) uptake in a patient with opsoclonus was measured by positron emission tomography (PET) and subsequently compared with the distribution in ten normal subjects. Statistical parametric mapping (SPM) revealed a decreased occipital FDG uptake in the patient, particularly at the posterior bank of the parieto-occipital sulcus (putative visual area PO/V6), in the region ventrally bordering V5, and anterolaterally in the calcarine sulcus. Such a specific pattern of occipital deactivation may indicate that opsoclonus suppresses the processing of visual motion along the magnocellular pathway. This is in agreement with normal saccadic suppression which has been proposed to contribute to the perception of a stable visual space.

Acute effects of thalamotomy and pallidotomy on regional cerebral metabolism, evaluated by PET.

The subacute effect of thalamotomy and pallidotomy on regional cerebral metabolism was studied by means of Positron Emission Tomography (PET). In this way we aimed to identify the pattern of functional deafferentiation following a specific lesion in the basal ganglia. The cerebral distribution of 2-[18F]fluoro 2-deoxy-D-glucose (FDG) uptake at 1-2 weeks after operation was compared with the uptake before operation. Analysis of the changes was done by statistical parametric mapping (SPM). Thalamotomy resulted in a reduction of FDG uptake in predominantly the lateral prefrontal- and the parietal cortex, whereas pallidotomy affected only uptake in the (pre)frontal cortex. The absence of change in the primary sensory-motor cortex after either surgical procedure may suggest that, in man, the motor portions of the thalamus exert a predominantly indirect influence on the human motor cortex.

Predicting outcome from coma: man-in-the-barrel syndrome as potential pitfall.

The Glasgow coma scale motor score is often used in predicting outcome after hypoxic-ischemic coma. Judicious care should be exerted when using this variable in predicting outcome in patients with coma following hypotension since borderzone infarction can obscure the clinical picture. We describe a patient who underwent skull base surgery for a schwannoma of the left facial nerve. The operation, which lasted for 10 h, was conducted under controlled hypotension. After the intervention the patient remained comatose with absent arm movements upon painful stimuli. An absent motor score usually carries a poor prognosis. However, magnetic resonance inversion recovery imaging of the brain showed bilateral hyperintense lesions in the arm-hand area indicative of borderzone ischemic damage. The patient received optimal supportive care and after 17 days he regained consciousness with 'man-in-the-barrel syndrome', which also further improved over time.

Unilateral pallidotomy in Parkinson's disease: a randomised, single-blind, multicentre trial.

BACKGROUND: The results of several cohort studies suggest that patients with advanced Parkinson's disease would benefit from unilateral pallidotomy. We have assessed the efficacy of unilateral pallidotomy in a randomised, single-blind, multicentre trial. METHODS: We enrolled 37 patients with advanced Parkinson's disease who had, despite optimum pharmacological treatment, at least one of the following symptoms: severe response fluctuations, dyskinesias, painful dystonias, or bradykinesia. Patients were randomly assigned to unilateral pallidotomy within 1 month or to pallidotomy after the primary outcome assessment (6 months later). The primary outcome was the difference between the groups in median changes on the motor examination section of the unified Parkinson's disease rating scale (UPDRS 3) score done in the off phase. Secondary outcome measures included levodopa-induced dyskinesias (dyskinesia rating scale [DRS]) and extent of disability (UPDRS 2). FINDINGS: The median UPDRS 3 off score of the pallidotomy patients improved from 47 to 32.5, whereas that of control patients slightly worsened from 52.5 to 56.5 (p<0.001). In the on phase the median DRS score improved 50% in pallidotomy patients compared with no change in controls. The UPDRS 2 off score improved with a median of 7 in the pallidotomy group. Two treated patients had major adverse effects. INTERPRETATION: Unilateral pallidotomy is an effective treatment in patients with advanced Parkinson's disease, who have an unsatisfactory response to pharmacological treatment.

Recurrent spontaneous intracerebral hemorrhage in a congenitally afibrinogenemic patient: diagnostic pitfalls and therapeutic options.

BACKGROUND: Coagulation disorders can cause intracerebral bleeding that may be difficult to detect since subsequent aberrant clot formation may mask early detection. This is an important pitfall because, when diagnosed early, bleeding in these patients is treatable. CASE DESCRIPTION: A patient with congenital afibrinogenemia presented with recurrent hemiparesis. Spontaneous intracerebral hemorrhage was diagnosed, despite an initial negative CT scan. Diagnosis, therapy, and complications of therapy are discussed. CONCLUSIONS: Intracerebral hemorrhage must be strongly suspected in any patient with a coagulation disorder presenting with matching clinical symptoms. Therapy must be installed immediately, before additional investigations, and should be continued even when initial neuroimaging is negative.

[Variable manifestations of Hashimoto's encephalopathy]. / Het variabele beeld van de Hashimoto-encefalopathie.

Two women (aged 12 and 32 years) and a man aged 40 years presented with fluctuating confusional states, depressed level of consciousness, seizures and tremor or myoclonic activity; hallucinations occurred in two of them. Laboratory examinations showed antibodies to thyroid peroxidase in serum, elevated protein levels in CSF and normal cerebral MRI. The EEG findings were indicative of diffuse encephalopathy. Hashimoto's encephalopathy was diagnosed. One patient improved dramatically on prednisone therapy, the other two patients recovered spontaneously. Hashimoto's encephalopathy is a subacute, fluctuating encephalopathy with combinations of impaired level of consciousness, involuntary movements, and epileptic or psychiatric symptoms. It occurs in patients with antithyroid antibodies. It is important to consider this diagnosis, since some patients may benefit from treatment with corticosteroids.

Motor function in a patient with bilateral lesions of the globus pallidus.

This study describes the long-term deficits of a patient who, after a toxic encephalopathy, sustained extensive bilateral damage to both segments of the globus pallidus (GP) and the right substantia nigra (SN). There were no signs of lesions of the pyramidal tracts or of other motor structures. The most obvious deficits were an abnormal gait with an exaggerated knee extension and a tendency to fall slowly, especially when pushed backward. In contrast, Romberg's test on an unstable platform was normal, as were long-latency leg reflexes induced by perturbations. Inadequate anticipatory and compensatory postural responses, in particular across the hip and knee joints, and slow movements seemed responsible for the falls. Muscle tone was normal but reflex studies showed signs of abnormal facilitation and inhibition at various levels of the neuraxis. We conclude that the GP and SN lesions caused defective input to premotor cortical and brain stem target zones. Dysfunctioning of these zones leads to improper control of the descending ventromedial motor system responsible for locomotion, postural control, and reflex status. The deficits in upper extremity motor performance included delayed and slow movements, inaccurate amplitudes of ballistic responses, a lack of predictive control, and deficits in bimanual coordination. Sensory feedback, proprioceptive more than visual, played a powerful compensating role in rapid aiming movements. Regional blood flow (studied using 15(O)2) was reduced in multiple frontal cortical regions, among which are the hand areas of the supplementary and premotor cortex. We hypothesize that this reflected impaired functioning of these areas, caused by defective bilateral output from GP and SN, and resulting in the motor deficits of the arm and hand.

Visualization of damaged brain tissue after ischemic stroke with cobalt-55 positron emission tomography.

UNLABELLED: In animal experiments, the radionuclide 55Co2+ has been shown to accumulate in degenerating cerebral tissue similar to Ca2+. METHODS: The potential role of 55Co2+ for in vivo brain PET imaging was investigated in four patients after ischemic stroke. RESULTS: PET showed uptake of 55Co2+ in damaged brain tissue irrespective of blood-brain barrier integrity, as affirmed by CT and MRI. CONCLUSION: Our preliminary results indicate that 55CoCl2 may prove to be a useful and relatively inexpensive PET radiopharmaceutical for visualization of degenerative processes in brain tissue.

Neurobehavioural changes in a patient with bilateral lesions of the globus pallidus.

This study has characterized the long-term neurobehavioural changes in a woman who, following the intake of an unidentified substance, sustained subtotal bilateral lesions of the globus pallidus and small lesions at selective sites adjacent to it. Associated with these lesions was a significantly reduced blood flow in multiple frontal cortical regions, most prominently in area 10, the anterior cingulate and the supplementary motor cortex. Her cognitive deficits were generally consistent with those found in patients with frontal lobe dysfunction but some deficits, i.e. in visual memory and learning, were more compatible with temporal lobe dysfunction. Incapacitating personality or obsessive compulsive changes as reported by others with similar lesions were absent and she could live independently. The cognitive changes are consistent with the view that the globus pallidus has important functions in mediating how internal representations of stimulus input are converted into various forms of action, for example, in planning solutions to problems and in working memory.

Head trauma and the risk of Alzheimer's disease.

A population-based case-control study of the association between head trauma and Alzheimer's disease was conducted in the Netherlands from 1980 to 1987. The study comprised 198 patients with clinically diagnosed early onset Alzheimer's disease and 198 age- and sex-matched population controls. Adjusted for sex, age, family history of dementia, and education, the odds ratio of a history of head trauma with loss of consciousness was 1.6 (95% confidence interval (CI) 0.8-3.4). The odds ratio for men was 2.5 (95% CI 0.9-7.0), and that for women was 0.9 (95% CI 0.3-2.8). The increase in odds ratio was limited to head trauma that occurred within the period of 10 years prior to the onset of dementia (odds ratio = 10.0; 95% CI 1.0-96.8). There was no evidence of effect modification by family history of dementia as measured on a multiplicative scale. However, the power to show interaction may have been low in this study. The authors' findings are compatible with the view that head trauma may be implicated in Alzheimer's disease, with a short lag time between the head trauma and the first symptoms of disease. The association needs to be confirmed in a prospective follow-up study to fully exclude the possibility of recall bias.

Is parental age related to the risk of Alzheimer's disease?

Advanced maternal and paternal age were investigated as putative risk factors for AD in 198 clinically diagnosed Alzheimer patients and in 198 randomly selected healthy controls. No significant differences in average age of fathers and of mothers at birth of the subject were observed. The risk of AD was not significantly different across categories of maternal and paternal age. The association with parental age was not different for sporadic and familial AD. These findings do not support the view of a maternal or paternal age effect on AD.

History of dementia and Parkinson's disease in 1st-degree relatives of patients with Alzheimer's disease.

We assessed the family history of dementia and Parkinson's disease in 198 Dutch patients with Alzheimer's disease diagnosed before the age of 70 years, and in 198 age- and sex-matched healthy population controls. Of the Alzheimer patients, 48% had at least 1 1st-degree relative with dementia, compared with 19% of the controls. There were 24 patients and 1 control with 2 or more 1st-degree relatives with dementia, yielding a relative risk of 40.0. More Alzheimer patients than controls had a 1st-degree relative with Parkinson's disease, with a relative risk of 2.9. This study strongly confirms earlier findings of familial aggregation of Alzheimer's disease and provides evidence for familial aggregation of Alzheimer's disease with Parkinson's disease. The latter may point at a joint etiology of these diseases.

Femoral neuropathy as a complication of aortic surgery.

In a series of 1006 aortic operations for atherosclerotic occlusive or aneurysmal disease a femoral neuropathy with paresis of the quadriceps femoris muscle and sensory disturbances occurred in 34 patients or 3.4%. The femoral nerve palsy was left-sided 23 times, right-sided 9 times and bilateral twice. Twenty-nine patients had a complete recovery after 1/2 to 1 years. It is suggested that the femoral neuropathy is of ischaemic nature and caused by aortic clamping. The scant blood supply of the intrapelvic section of the femoral nerve is derived from the iliolumbar artery, a branch of the internal iliac artery, and from the deep circumflex iliac artery, a branch of the external iliac artery. On the right side the deep circumflex iliac artery gives more branches to the nerve and there are more anastomoses with the fourth and fifth lumbar arteries, than on the left side. This may be the explanation for the preference of the nerve palsy for the left side.

Signs of focal posterior cerebral abnormality in early subacute sclerosing panencephalitis.

In 16 cases of subacute sclerosing panencephalitis (SSPE), praxis and visual spatial capacities were more impaired early in the disease than were language functions. Together with the electroencephalographic findings, this suggests that the early lesions in SSPE are more pronounced in the parietooccipital area than in the classic language areas. Other reports also support such a localization. Detection of the disease in its early phase when dressing apraxia and visual impairment predominate is important in conducting clinical trials of different therapeutic agents.

Carotid endarterectomy: does it improve cognitive or motor functioning?

In a group of 20 patients who were to undergo endarterectomy for atherosclerotic occlusive disease of the internal carotid artery, the stenosis did not appear to have resulted in cognitive or motor deficits. Consistent with this finding, surgery could not be shown to have a beneficial effect on cognitive or motor functioning. Control data were supplied by 20 patients who underwent peripheral vascular surgery and 20 healthy subjects. The test-retest interval was 10 weeks.