[Usefulness of SPECT and MRI in the diagnosis of atypical parkinsonism].

Background: Clinico-pathological studies have shown that only three out of four patients with parkinsonism have idiopathic Parkinson's disease. In patients with so-called Parkinson plus syndrome, the degeneration in the brain is more widespread and the variety of neurological signs greater than in Parkinson's disease. The differentiation of these syndromes from Parkinson's disease can be difficult.

Linkage analysis narrows the critical region for oculodentodigital dysplasia to chromosome 6q22-q23.

Oculodentodigital dysplasia (ODDD) is an autosomal dominant condition with high penetrance and variable expressivity. The anomalies of the craniofacial region, eyes, teeth, and limbs indicate abnormal morphogenesis during early fetal development. Neurologic abnormalities occur later in life and appear to be secondary to white matter degeneration and basal ganglia changes.

[Perimesencephalic subarachnoid hemorrhage].

Acute, non-traumatic subarachnoid haemorrhage is usually caused by a ruptured aneurysm. This is a serious condition involving high mortality. Perimesencephalic haemorrhage has recently been identified as a clinical subset of subarachnoid haemorrhage.

Midbrain tremor and hypertrophic olivary degeneration after pontine hemorrhage.

A severe rest tremor arose in a patient's right arm 9 months after a pontine tegmental hemorrhage. Magnetic resonance studies at 4 and 10 months showed residual hemosiderin in the pons and increasing hypertrophic olivary degeneration (HOD) affecting primarily the left olive. The tremor was refractory to pharmacotherapy (clonazepam, propranolol, and levodopa), but was reduced after implantation of a thalamic stimulator device.

Assessment of the ophthalmic artery as a collateral to the cerebral circulation. A comparison of transorbital Doppler ultrasonography and regional cerebral blood flow measurements.

The role of the ophthalmic artery (OA) as a collateral to the cerebral circulation in carotid occlusive disease is somewhat controversial. The aim of this study was to assess the importance of this collateral by comparing the results of transorbital Doppler ultrasonography and regional cerebral blood flow measurements using SPECT and Xenon-133 inhalation in 41 patients with unilateral high-grade internal carotid artery occlusive disease. Both measurements were performed under basal conditions and after the intravenous administration of 1 g acetazolamide to test cerebral vasoreactivity.

Reduced Global Cerebral Blood Flow in Non-Demented HIV Positive Patients.

Twelve non-demented HIV positive men with different degrees of immunodeficiency were examined with single photon emission computed tomography (SPECT). Reduction in relative global cerebral blood flow was found in HIV positive patients compared to healthy HIV negative controls (p = 0.014).

Cerebral vasoreactivity assessed with transcranial Doppler and regional cerebral blood flow measurements. Dose, serum concentration, and time course of the response to acetazolamide.

Background And Purpose: To improve the assessment of cerebral vasoreactivity using acetazolamide (ACZ), we studied the time course of the response and the relationship between dose, response, and serum concentration.

Methods: Blood flow velocities were measured with the use of transcranial Doppler ultrasonography in one of the middle cerebral arteries of 48 healthy subjects after the intravenous administration of 1 to 1.6 g ACZ.

Doppler study of the ophthalmic artery in patients with carotid occlusive disease.

Assessing the adequacy of collateral circulatory pathways has become increasingly important in the investigation of cerebral circulation. Using transorbital Doppler ultrasonography (TOD), we examined the ophthalmic artery (OA) in patients with hemodynamic significant internal carotid artery (ICA) occlusive disease. The velocity and the direction of flow in the OA were studied in 45 patients (occlusion n = 27, stenosis > 75% n = 18), and in 30 age matched controls, under baseline conditions and within 30 minutes after the i.

Simultaneous assessment of vasoreactivity using transcranial Doppler ultrasound and cerebral blood flow in healthy subjects.

Blood flow velocities in both middle cerebral arteries and regional cerebral blood flow in their perfusion territories were measured simultaneously in 36 healthy subjects. In 20 subjects, the measurements were first performed under basal conditions and then repeated 15-20 min after an intravenous injection of 1 g of acetazolamide. Reproducibility of simultaneous blood flow and velocity measurements was tested by examining 16 subjects on two occasions under basal conditions with an interval of 20 min.

Ocular and cerebral blood flow measurements in healthy subjects. A comparison of blood flow velocity and dynamic tonometry measurements before and after acetazolamide.

The ocular and cerebral blood flow was studied in 15 healthy subjects using transcranial Doppler ultrasonography (2 MHz). The blood flow velocity in the precerebral carotid arteries, in the ophthalmic artery and in the middle cerebral artery was measured under baseline conditions and after i.v.

Cerebral vasoreactivity in unilateral carotid artery disease. A comparison of blood flow velocity and regional cerebral blood flow measurements.

Background And Purpose: Hemodynamic information obtained by assessing cerebral vasoreactivity is of clinical interest and may have prognostic significance in patients with occlusive carotid disease. The aim of this study was to compare the results of transcranial Doppler and regional cerebral blood flow studies when used to assess cerebral vasoreactivity.

Methods: Blood flow velocities in both middle cerebral arteries and regional cerebral blood flow in their respective perfusion territories were compared in 52 patients with severe unilateral carotid stenosis or occlusion.

A comparison of regional cerebral blood flow and middle cerebral artery blood flow velocities: simultaneous measurements in healthy subjects.

Blood flow velocities were measured in both middle cerebral arteries (MCAs) of 36 healthy subjects using transcranial Doppler ultrasound. Measurements were first made using a hand-held probe. Velocities were then studied bilaterally with fixed probes under resting conditions and during simultaneous regional CBF (rCBF) measurements.

[Botulinum toxin treatment of spastic torticollis].

Botulinum toxin A was administered to 19 patients with spasmodic torticollis. A significant decrease of abnormal head and neck movements was recorded, and all the patients who suffered pain reported relief. Side effects were minor and transient.

Cerebral blood flow findings in moyamoya disease in adults.

Three adult patients with moyamoya disease are described. They presented with intracerebral hematoma, cerebral infarction and subarachnoid hemorrhage, respectively. Subarachnoid hemorrhage is rare in moyamoya and is usually the result of aneurysm rupture.

Regional cerebral blood flow after long-term exposure to carbon disulfide.

Sixteen former rayon viscose workers were investigated four years after the exposure to carbon disulfide was discontinued. Median age was 58 years (range 43-65 years), median exposure time was 17 years (range 10-35 years). Encephalopathy was diagnosed in altogether 14 workers.

[Autoimmune optic neuritis].

We describe two patients with autoimmune optic neuritis. The initial symptom was severe loss of vision without clinical signs or symptoms of systemic autoimmune disease. The patients had recurrent attacks of optic neuritis in both eyes, causing permanent visual impairment despite conventional doses of corticosteroid.

A comparison of transcranial Doppler and cerebral blood flow studies to assess cerebral vasoreactivity.

Background And Purpose: The aim of this study was to determine the ability of transcranial Doppler ultrasonography when used to assess cerebral vasoreactivity. The results of this method were compared with regional cerebral blood flow measurements.

Methods: Forty-three patients with symptoms suggesting cerebrovascular disease took part.

[Treatment of focal dystonia with botulinum toxin].

Focal dystonia and hemifacial spasms are difficult to treat. Medication and surgery may suppress the dystonic movements but the improvement is not satisfactory. The present article reviews use of Botulinum toxin in cases of focal dystonia.

Chiasmal optic neuritis.

We describe two cases of chiasmal optic neuritis. The presenting symptoms were reduced visual acuity and bitemporal visual field defects. The enlargement of the optic chiasm in the acute stage and normalization after recovery is demonstrated by magnetic resonance imaging (MRI).

[Spontaneous dissection of the internal carotid artery].

Spontaneous dissection of the internal carotid artery is supposed to be a rare condition, but seems to be increasingly diagnosed. The symptoms are protean from unilateral headache, Horners syndrome, tinnitus, to cerebral ischemia and hemipareses. The condition is of unknown incidence and usually affects previously healthy persons.

Cerebral vasoreactivity and blood flow before and 3 months after carotid endarterectomy.

We measured regional cerebral blood flow and cerebral vasoreactivity before and 3 months after carotid endarterectomy using xenon-133 inhalation with single-photon emission computed tomography and the acetazolamide test in 14 selected patients who had suffered cerebral transient ischemic attacks due to an ipsilateral internal carotid artery stenosis. The patients had neither clinical nor cerebral computed tomographic evidence of infarction. Baseline regional cerebral blood flow was symmetrical before and unchanged after endarterectomy.

Cluster headache: transcranial Doppler ultrasound and rCBF studies.

Transcranial Doppler and rCBF examinations were carried out in 25 cluster headache patients. Spontaneous and glyceryl trinitrate (nitroglycerin) provoked attacks were accompanied by a bilateral decrease in middle cerebral artery blood flow velocities. This decrease was more pronounced on the symptomatic side but the difference did not reach statistical significance.