Incidence of rotational vertigo in supratentorial stroke: a prospective analysis of 112 consecutive patients.

BACKGROUND: Single cases with hemispheric, cortical or subcortical, ischemic lesions presenting with rotational vertigo (RV), that challenge the notion of infratentorial or peripheral generation of RV have been published, but the incidence of this symptom in a larger series is unknown. The aim of this study was to investigate whether acute hemispheric cerebrovascular lesions cause vertiginous sensations with particular emphasis on RV. METHODS: A total of 112 consecutive stroke patients were assessed in a prospective single-center study over a 22-month inclusion period. Rotational or other vertiginous sensations were assessed using a structured 5-item questionnaire and patients with vertigo were further evaluated with Yardley's Vertigo Symptom Scale. All subjects underwent standard clinical neuro-ophthalmological and neuro-otological testing and data were correlated to imaging findings. RESULTS: RV was absent among our patients. Few subjects reported non-rotational vertiginous sensations with stroke onset. These were mainly right-hemispheric strokes with concomitant subcortical leukoaraiosis. CONCLUSION: In this case series we did not find any patients with spinning sensations which is supportive of the dogma that supratenotrial lesions do not cause RV. Certain hemispheric stroke patterns, however, may be related to non-rotational dizziness.

Vertical and horizontal integrator failure in a ponto-medullary infarction: A possible role for paramedian tract neurons.

Gaze-evoked nystagmus is caused by a "leaky" neural integrator, which fails to maintain eccentric gaze positions after centrifugal eye movements. It is usually observed as the result of toxic, metabolic or paraneoplastic disorders, rather than single structural lesions. We demonstrate a case of an omnidirectional gaze-evoked nystagmus due to an ischemic paramedian ponto-medullar infarction. The most probable explanation is a damage of paramedian tract neurons, which have been recently recognized as a site of neural integration.

Common carotid arterial stiffness and the risk of ischaemic stroke.

In the present case-control study we aimed to investigate the association of common carotid arterial (CCA) stiffness with ischaemic stroke (IS) and to determine whether this relationship was independent of conventional risk factors including CCA intima-media thickness (CCA-IMT). CCA distensibility, defined as the change of CCA-diameter during the cardiac cycle, and CCA-IMT were evaluated by means of high-resolution B-mode carotid ultrasound examination in consecutive, first-ever IS patients (n=193) and in age- and sex-matched control subjects (n=106). The CCA distensibility (inverse of CCA stiffness) was significantly (P=0.007) lower in IS (0.353 mm, 95% CI: 0.326-0.379) than in control subjects (0.415 mm, 95% CI: 0.378-0.451) even after adjusting for blood pressure values, diastolic CCA-diameter and height. The multivariate logistic regression procedure selected CCA-IMT and CCA distensibility as the only independent predictor variables of IS. Each 1 SD increase in the CCA-IMT and each 1 SD decrease in the CCA distensibility independently increased the likelihood of IS by 167.0% (OR: 2.67, 95% CI: 1.80-3.96, P<0.001) and 59.0% (OR: 1.59, 95% CI: 1.22-2.07, P=0.001) respectively. Increased CCA stiffness is associated with IS independent of conventional risk factors and CCA-IMT. The causal interrelationship between the elastic properties of the CCA and the risk of stroke deserves further investigation by longitudinal studies.

Common carotid artery intima-media thickness for the risk assessment of lacunar infarction versus intracerebral haemorrhage.

BACKGROUND AND PURPOSE: Arterial hypertension is the major risk factor for intracerebral haemorrhage (ICH) and lacunar infarction (LI) and both types of cerebral lesions originate from pathology of the same deep perforating small arteries. We aimed to evaluate the relationship between vascular risk factors including common carotid artery intima-media thickness (CCA-IMT) with LI versus ICH. METHODS: We prospectively collected data from 159 first ever stroke patients (67 cases with ICH and 92 cases with LI) with documented history of hypertension. All subjects underwent B-mode ultrasonographic measurements of the CCA-IMT. Logistic regression modelling was used to determine the factors (established vascular risk factors, severity and duration of hypertension, concomitant medications and CCA-IMT) that may significantly differentiate LI from ICH. RESULTS: Patients with LI had significantly (p=0.002) larger CCA-IMT values (0.926 mm, 95% CI: 0.881-0.971) than subjects with ICH (0.815 mm, 95% CI: 0.762-0.868) even after adjusting for baseline characteristics and cardiovascular medications. The multivariate logistic regression procedure selected CCA-IMT, diabetes mellitus and hypercholesterolaemia as the only independent factors able to discriminate between LI and ICH. The risk for LI versus ICH increased continuously with increasing CCA-IMT. For each increment of 0.1 mm in CCA-IMT the probability of suffering from LI versus ICH increased by 36.6% (95 % CI: 13%-65.2%, p=0.001) even after adjustment for cardiovascular risk factors. CONCLUSIONS: Increased CCA-IMT values are a factor favouring LI over ICH in hypertensive patients. The measurement of CCA-IMT may be a useful non-invasive diagnostic tool for the risk assessment of LI with respect to ICH in such patients.

Bilateral paramedian midbrain infarct: an uncommon variant of the "top of the basilar" syndrome.

Occlusion of the rostral portion of the basilar artery can result in ischaemia of the midbrain and thalami, as well as of the temporal and occipital lobes. The so called "top of the basilar" syndrome manifests clinically as numerous combinations of abnormalities of alertness, sleep-wake cycle, and behaviour and oculomotor or pupillomotor functions. A 67 year old man presented with bilateral internuclear ophthalmoplegia, rubral tremor, and daytime somnolence. He was awake during the night and mostly agitated and aggressive. An ischaemic lesion was visible on the magnetic resonance (MR) image in the central portion of the midbrain just ventral to the aqueduct, clearly affecting the paramedian structures bilaterally. MR angiographic images demonstrated a hypoplastic basilar artery ending in both superior cerebellar arteries. Both posterior cerebral arteries were seen to arise from the corresponding internal carotid arteries via the posterior communicating branches. This unique case of an acute bilateral paramedian infarct represents a highly uncommon variant of the "top of the basilar" syndrome and was due to the affected ischaemic territory--that is, the "distal field" of the variant basilar artery.

[Factors influencing secondary preventive blood pressure control in hypertensive stroke patients]. / Einflussfaktoren auf die effektive Blutdruckeinstellung im Rahmen der sekundären Schlaganfallprophylaxe.

BACKGROUND: More than half of patients with documented hypertension surviving cerebrovascular events do not have their blood pressure (BP) controlled, despite the use of antihypertensive medication. Data on the possible reasons for poor BP control in stroke survivors are limited. METHODS: We evaluated prospectively parameters influencing the effectiveness of BP control in hypertensive stroke survivors who were followed up. RESULTS: At 3 months after stroke BP was effectively controlled in only 38.8% of patients. Diabetes mellitus had a negative influence on the effectiveness of antihypertensive medication by reducing significantly the chance of achieving a significant BP reduction, while patients suffering from coronary artery disease had an increased chance of getting their BP under control within 3 months after stroke onset. Diuretic medication was found to be an independent positive predictor for effective antihypertensive control. Combined therapy including diuretics was significantly more effective than antihypertensive monotherapy. CONCLUSIONS: Arterial pressure control in stroke survivors is poor. Risk factor profile, manifest heart disease, and the chosen antihypertensive medication are factors of prognostic relevance for effective BP control.

Prognosis of stroke in the south of Greece: 1 year mortality, functional outcome and its determinants: the Arcadia Stroke Registry.

OBJECTIVES: For Greece, data on incidence of stroke, type of stroke, and prognosis of stroke is limited. Recently, results on incidence of stroke were published. Here 1 year mortality, functional outcome after a first ever stroke, and determinants of the prognosis are described. METHODS: A population based registry was established in the Arcadia area, located in eastern central Peloponessos in southern Greece. Between 1 November 1993 and 31 October 1995, 555 patients with a first ever stroke were identified using information from death certificates, hospital records, public health centres and general practitioners. Extensive information on cardiovascular risk factors and stroke characteristics was obtained. After 1 year a modified Rankin score was determined in all surviving patients. RESULTS: After 1 year of follow up, 204 (36.8%) patients died. The probability of survival 1 year after stroke was higher for cerebral infarction than for intracerebral haemorrhage; 67.8% (95% confidence interval (95% CI) 64-72) and 46.4% (35-57), respectively. Of the survivors, 68.9% had either no symptoms or symptoms that would not interfere with their capacity to look after themselves (Rankin score 0 to 2). Increasing age and low Glasgow coma scale score were the most powerful predictors of death within 1 year (p<0.01), whereas increasing age, atrial fibrillation, and low Glasgow coma scale score were the most important predictors of functional outcome 1 year after a stroke (p<0.01). CONCLUSIONS: One year mortality from stroke in Greece is similar to that of other industrialised countries. The most important factors that affect the prognosis of a patient with a first ever stroke are increasing age, stroke severity, and atrial fibrillation.

The Athens stroke registry: results of a five-year hospital-based study.

The advent and wide application of new technology, especially noninvasive techniques, has enabled physicians to more completely investigate and clarify the etiopathogenic mechanisms of stroke. Such data have not been available until recently for Southeastern Europe. In addition, during the last decades, strategies for the modification of risk factors and primary prevention may have changed the prevalence of each subgroup of stroke as well. We investigated 1, 042 consecutive patients who had first strokes, during a period of 5 years (from June 1992 to May 1997) and classified them prospectively based on etiopathogenic mechanisms. Patients with transient ischemic attacks and subarachnoid hemorrhage were excluded. There were 613 male and 429 female patients, with a mean age of 70.2 +/- 11.9 years. Forty-six percent of the patients arrived within 3 h from stroke onset. The probable mechanisms were: large-artery atherosclerosis, 156 (15%); lacunes, 177 (17%); cardioembolic, 335 (32.1%); infarct of unknown cause, 182 (17.5%); miscellaneous causes, 35 (3.3%), and intracerebral hemorrhage (ICH), 157 (15.1%). In the cardioembolic group, nonvalvular atrial fibrillation (NVAF) was the probable cause in 225 patients, especially in patients older than 75 years (65%). The overall hospital mortality was 15.2% (from 0.6% for lacunar stroke to 34% for ICH). In our population, cardioembolism is the most frequent subtype of stroke. NVAF is the most likely source, especially in older patients.

Enamel color change by microabrasion and resin-based composite.

A simple technique using microabrasion with hydrochloric acid/pumice and resin-based composite to improve the esthetics of discolored anterior teeth is described.

Stroke incidence and case fatality in southern Greece: the Arcadia stroke registry.

BACKGROUND AND PURPOSE: For Greece, information on incidence of stroke and distribution of type of stroke has not been reported. We determined the incidence of first-ever stroke in men and women, the incidence of stroke by type, and the associated case fatality. METHODS: A population-based registry was established in the Arcadia province, located in eastern central Peloponessos, in the southern part of Greece. Between November 1, 1993, and October 31, 1995, all subjects with a first-ever stroke were identified. For case ascertainment, information from death certificates, hospital records, public health centers, and general practitioners was used. RESULTS: During a 24-month period, 555 subjects with a first-ever stroke were registered. The incidence rates (per 100 000) by age group (18 to 34, 35 to 44, 45 to 54, 55 to 64, 65 to 74, 75 to 84, >/=85 years) for men were 5, 31, 113, 240, 662, 1275, and 3218, respectively. For women, the rates were 11, 18, 48, 196, 478, 1166, and 2137, respectively. Age- and sex-standardized to the European population, the annual incidence rate for subjects aged 45 to 84 years was 319.4/100 000 (95% CI, 283 to 356). In men, cerebral infarction was diagnosed in 81% of cases, intracerebral hemorrhage in 16%, and subarachnoid hemorrhage in 2%. For women, these figures were 85%, 12%, and 3%, respectively. The 28-day case fatality rate was 26.6% (95% CI, 22.9% to 30.2%), with no differences between men and women. Case-fatality increased with age and was higher for intracerebral hemorrhage than for cerebral infarction. CONCLUSIONS: The incidence of stroke in our population-based study ranks low part compared with other European studies. The distribution of stroke types and case fatality rate appear to be similar to those of other industrialized countries.

Hereditary neuropathy with liability to pressure palsies: the same molecular defect can result in diverse clinical presentation.

Hereditary neuropathy with liability to pressure palsies (HNPP) is a peripheral nerve disorder characterized by autosomal dominant inheritance, recurrent pressure palsies, reduced motor and sensory conduction velocities and sausage-like swellings (tomacula) of myelin sheaths in nerve biopsy. Two young adult patients are reported as index cases of two families in which HNPP was diagnosed. The first patient presented with recurrent pressure palsies, whereas the second suffered from fasciculations and myokymias in his right hand, with difficulty in writing, and upper and lower limb paraesthesias of 3 years' duration. Electrodiagnostic studies revealed slowing of conduction primarily in common sites of compression in both patients. Sural nerve biopsy revealed the characteristic tomaculous swellings in both patients. DNA analysis showed that both patients have a deletion in chromosome 17p11.2 which is found in the majority of HNPP cases. In light of the common molecular defect, the different clinical symptomatology of the two patients is discussed.

Analgesia induced by morphine injected into the pallidum.

Bilateral microinjections of morphine hydrochloride (10; 20; 30 micrograms/0.5 microliter/side) or saline were aimed at three different regions of the rat globus pallidus: dorsal, medial, ventral. Before and at various intervals after intrapallidal morphine (15; 30; 60; 90; 180 min), estimation of pain threshold was made by the hot plate procedure. Dose-dependent morphine analgesia was elicited from all three regions injected. Differences between the pallidal areas as to the intensity and duration of the drug's effect were noticed. Pretreatment with subcutaneous naloxone (1 mg/kg, s.c.) inhibited the morphine (20 micrograms) analgesia elicited from the medial and dorsal pallidum; it decreased and delayed the effect of morphine injected into the ventral pallidum. The results suggest that the three pallidal areas tested are involved to a different degree (medial/dorsal greater than ventral) in the morphine analgesia mediated by opiate receptors.

Acquisition and extinction of L-maze and conditioned avoidance behaviours following kainic acid-induced lesions of the ventromedial thalamic nuclei in rats.

Rats with kainic acid-induced lesions of the ventromedial thalamic (VMt) nucleus were compared with sham-operated controls on two behavioural tasks. The kainic acid injection resulted in loss of local neurons in the VMt nuclei with no appreciable damage to other thalamic nuclei or to other distant brain areas. VMt nuclei lesion animals learned to run in an L-maze for food reinforcement and to avoid electric foot-shock in the two way active avoidance shuttle-box procedure. Extinction of the food reinforced response was not altered by the lesion. One week retention of the acquired two-way active avoidance response was almost abolished on the animals with the lesion. Open field locomotion or escape latencies were not influenced by the lesion. It is concluded that VMt nuclei of rats are involved in the retention of aversively reinforced behaviours.