Additional value of quantitative EEG in acute anterior circulation syndrome of presumed ischemic origin

Objective

The clinical course of acute stroke can be highly variable and for effective management outcome prediction needs to be refined. We investigated whether EEG parameters are of additional diagnostic and prognostic value in the early phase of acute ischemic anterior circulation stroke.

Methods

Ninety-four patients presenting with acute anterior circulation syndrome (ACS) of presumed ischemic origin were incrementally included. Clinical characteristics were correlated with volume of ischemia and EEG parameters. Predictive values for definite stroke, early neurological deterioration, spontaneous early neurological improvement and death within 1 week after ACS were calculated using ROC curves and logistic regression modelling.

Results

In patients with normal or near normal NIHSS score of 0 or 1, the pairwise derived brain symmetry index (pdBSI) was an independent predictor for definite stroke displaying an overall accuracy of 80%. Early neurological deterioration was independently predicted by pdBSI with a correct classification rate of 95%. In ROC analysis, death was predicted by pdBSI with overall accuracy of 97%. Spontaneous neurological improvement was independently predicted by the delta + theta/alpha + beta – ratio with overall accuracy of 75%. Small-vessel stroke was independently predicted by pdBSI with a correct classification rate of 92%.

Conclusions

EEG may be of prognostic value for spontaneous neurological improvement, early neurological deterioration and death in the acute setting of acute anterior circulation syndrome of presumed ischemic origin.

Significance

These findings may have an impact on stroke care.     

Long-term health-related quality of life after decompressive hemicraniectomy in stroke patients with life-threatening space-occupying brain edema

Background

Although randomized clinical trials have reported significant improvement in mortality and functional outcome as measured with modified Rankin Scale (mRS) or Barthel index (BI) in stroke patients with space-occupying anterior circulation infarctions treated with hemicraniectomy, many clinicians are still concerned about the long-term health-related quality of life (HRQoL).

Aim

Assessment of HRQoL after hemicraniectomy to holistically reevaluate clinical outcome.

Methods

Eleven patients (6 men, 5 women; mean age 48 (SD 5.8) years) were examined at 9–51 months after hemicraniectomy. Test batteries comprised NIH stroke scale, BI, mRS, neuropsychological tests (Visual Object and Space Perception Battery and clock test), and HRQoL-scales (Short Form 36 Health Survey (SF-36), Nottingham Health Profile (NHP), Questions on Life Satisfaction, Hospital Anxiety and Depression Scale and EQ-5D).

Results

Median values for NIHSS, BI and mRS were 11.5, 55 and 3.5. In HRQoL-scales, subscales related to physical mobility and functioning were consistently severely impaired, while subscales related to psychological well-being were impaired to a lesser extent. Mean scores for physical functioning and physical role were 10.5 and 12.5 in the SF-36, and 61.3 and 43.3 for physical mobility and energy in the NHP; emotional role and mental health scored 63.3 and 66.4 (SF-36), scores for emotional reaction and social isolation were 18.9 and 16.0 (NHP), respectively.

Conclusion

Although, physical components of HRQoL are highly impaired, these stroke patients achieved a satisfying level of psychological well-being which was endorsed by a nearly unanimous retrospective appraisal of life-saving hemicraniectomy.     

Prognosis of aphasia in stroke patients early after iv thrombolysis

Objective

Stroke patients with aphasia have a high long-term morbidity. Intravenous rt-PA (iv) thrombolysis is given more deliberately to these patients. Early outcome data is lacking. Aim of this study was to determine early benefit from rt-PA in patients with aphasia.

Methods

Data of stroke patients treated by iv thrombolysis was scrutinized for the presence of aphasia defined as ≥1 point for aphasia on the National Institute of Health Stroke Scale (NIHSS). Improvement was defined as a gain of ≥1 point within 24 h. Cranial computed tomography (CT) scans were evaluated regarding early ischemic changes (EICs), infarct volume and localization.

Results

Fifty patients with aphasia were included. 16 (32%) of patients improved (4 (36%) minor, 7 (41%) moderate, 5 (23%) major stroke patients), while 44 (62%) remained unchanged. Of 28 patients with EICs, 10 (36%) improved compared to 7 out of 22 (32%) patients without (p = 0.773). Aphasia outcome was significantly associated with infarct volume at admission and at 24 h (Kruskal–Wallis, p = 0.033, p ≤ 0.001, respectively).

Conclusion

EICs are not predictive of aphasia outcome and patients with improvement showed smaller infarct volumes. One third improved within 24 h, while two thirds remained unchanged. This might justify a closer follow-up of aphasia in stroke patients at the acute stage.     

Preliminary findings of the effects of autonomic dysfunction on functional outcome after acute ischemic stroke

Background and purpose

Impaired autonomic function is common in the acute poststroke phase but little is known about its effects on functional outcome after acute ischemic stroke. This study sought to investigate the impact of autonomic dysfunction by Ewing's classification on functional outcome 2 months after acute ischemic stroke.

Methods

34 consecutive acute ischemic stroke patients within 7 days after onset were enrolled. On admission, autonomic function was assessed by Ewing's battery tests. Stroke severity was assessed by the National Institutes of Health Stroke Scale (NIHSS), autonomy in activities of daily living by the Barthel Index (BI), and global disability by the modified Rankin Scale (mRS). BI and mRS were also evaluated 2 months after ischemic stroke onset.

Results

On admission, eight patients were diagnosed as minor autonomic dysfunction and 26 patients as relatively severe autonomic dysfunction. The prevalence of relatively severe autonomic dysfunction in ischemic stroke patients was 76.5%. There were no significant differences in baseline characteristics between the minor and severe autonomic dysfunction groups. 2 months after stroke onset, the mean BI score of patients with minor autonomic dysfunction and severe autonomic dysfunction increased from 76.3 ± 15.3 on admission to 95.0 ± 7.1, 66.5 ± 15.2 on admission to 74.8 ± 15.9 respectively. The mean BI score after 2-month stroke onset and the change in BI from admission to 2-month outcome (delta BI) in patients with severe autonomic dysfunction were lower than those in patients with minor autonomic dysfunction (all P < 0.05).

Conclusions

Autonomic dysfunction occurs in acute stroke patients. Relatively severe autonomic dysfunction is related to an unfavorable functional outcome in patients with acute ischemic stroke.     

Laterality is an Independent Predictor of Endovascular Thrombectomy in Patients With Low National Institute of Health Stroke Scale

Objective

Endovascular thrombectomy (ET) for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO) is offered to select patients meeting strict criteria. One of the criteria is stroke severity as indicated by the National Institute of Health Stroke Scale (NIHSS). Inherently, NIHSS is biased towards left hemisphere strokes (LHS) with median NIHSS score 4 points higher than right hemisphere strokes (RHS). This may potentially affect clinical decision making and thrombectomy eligibility. We sought to test this hypothesis.

A simple risk score for early ischemic stroke mortality derived from National Institutes of Health Stroke Scale: A discriminant analysis

Objectives

The aim of the current study was to design a new simpler form of National Institutes of Health Stroke Scale (NIHSS) for use in emergency settings, and compare its predictive ability with original NIHSS score for mortality.

Methods

A total of 152 consecutive patients with first ever ischemic stroke admitted to a university affiliated hospital were recruited. NIHSS score on admission was estimated and the predictive ability of NIHSS items for mortality at 28 days was evaluated by logistic regression. Stepwise discriminant analysis was performed on NIHSS items to obtain a discriminant function with the best discriminative ability for mortality. Further, receiver operating characteristics (ROC) curves were depicted to compare the new determined discriminant function with the original NIHSS score.

Results

Cumulative rate of mortality was 11.8% for 28-day follow-up period. Among NIHSS items, scores of visual field, limb ataxia and extinction neglect were not associated with mortality (P > 0.05). On the contrary, level of consciousness-commands, language and gaze were determined as independent indicators of mortality (P < 0.05), and their coefficients on discriminant function were equal to 0.65, 0.44 and 0.30, respectively. In addition, area under the ROC curve of the calculated discriminant function was not statistically different from NIHSS score (P > 0.05).

Conclusions

The suggested discriminant function, comprising NIHSS items of level of consciousness-commands, language and gaze, can predict 28-day mortality after ischemic stroke in a similar way to the original NIHSS score and can provide a baseline for stroke severity in emergency settings.     

Plasma heart-type fatty acid binding protein level in acute ischemic stroke: Comparative analysis with plasma S100B level for diagnosis of stroke and prediction of long-term clinical outcome

Objectives

Heart-type fatty acid binding protein (H-FABP) is enriched in neuronal cell body as well as myocardium, and is rapidly released from damaged neuron into circulation in cerebral ischemia. We performed a comparative analysis between plasma H-FABP and S100B levels in the acute phase of ischemic stroke.

Methods

The present study included 111 consecutive patients with acute ischemic stroke and 127 control subjects. Measurement of plasma H-FABP and S100B levels was conducted during acute phase (<24 h) of stroke. Clinical severities were evaluated by the use of NIHSS scores at admission and mRS score at 3 months after symptom onset.

Results

Both the plasma H-FABP and S100B levels were significantly higher in stroke group than control group. In multiple logistic regression analysis, statistical significance of both markers remained significant after adjusting the vascular risk factors. In the receiver operator characteristic (ROC) curve analysis, neither H-FABP (area under curve [AUC] = 0.71, P < 0.001, sensitivity: 59.5%, specificity: 79.5%) nor S100B (AUC = 0.70, P < 0.001, sensitivity: 54.0%, specificity: 83.5%) showed a favorable degree of diagnostic value to discriminate stroke from stroke mimic. Plasma H-FABP (r = 0.46, P < 0.01) and S100B (r = 0.45, P < 0.01) were correlated with initial NIHSS score, and both marker were significantly higher in patients with poor clinical outcome.

Conclusion

Although plasma H-FABP is elevated in the acute phase of ischemic stroke, the diagnostic accuracy of H-FABP as a sole marker is not sufficient to be applied in the clinical setting. Plasma H-FABP can be used as a potential marker for stroke prognosis.     

Atrial fibrillation predicts good functional outcome following intravenous tissue plasminogen activator in patients with severe stroke

Objective

Atrial fibrillation (AF) is associated with poor outcome after intravenous thrombolysis probably due to greater pretreatment stroke severity. We conducted this retrospective study to determine whether AF is an independent predictor for clinical outcome in patients stratified by initial stroke severity.

Methods

A total of 143 acute ischemic stroke patients who received intravenous thrombolysis within 3 h after onset were enrolled. The patients were categorized according to the baseline stroke severity by National Institute of Health Stroke Scale (NIHSS) score (≤10 vs. >10) and the presence of AF or not. Favorable 90-day outcome was defined as a modified Rankin Scale (mRS) score < 2.

Results

Among the 100 patients with severe stroke (NIHSS > 10), those with AF (n = 52) had a higher proportion of favorable 90-day outcome than those without AF (31% vs. 8%, P = 0.005). After adjustment for age, baseline glucose level, and onset to treatment time, the difference remained significant (odds ratio 5.80, 95% confidence interval 1.63–20.68). In patients with mild stroke (NIHSS ≤ 10), no difference in clinical outcome was found between AF (n = 20) and non-AF (n = 23) groups.

Conclusion

Presence of AF was associated with favorable 90-day outcome following intravenous thrombolysis in patients with severe stroke at baseline, while the association did not exist in patients with mild stroke.     

Evaluation of the intravenous magnesium sulfate effect in clinical improvement of patients with acute ischemic stroke

Background

Evidence is mounting that magnesium may play a critical role in the development of strokes and the healing process during and after a stroke. Magnesium is an N-methyl-d-aspartate (NMDA) glutamate receptor antagonist that has been shown to be neuroprotective in many preclinical models of ischemic and excitotoxic brain injury. This study was performed to evaluate the intravenous magnesium sulfate effect in clinical improvement of patients with acute ischemic stroke.

Methods

One hundred and seven patients with acute ischemic stroke signs and symptoms lasting less than 12 hours were included in the study and were divided into two groups, 55 patients received 4 g of MgSO₄ over 15 minutes and then 16 g over the next 24 hours, and 52 patients were received matching placebo. The study primary end point was stroke related neurologic deficit evaluation by the national institute of stroke scale (NIHSS).

Results

Patients receiving MgSO₄ showed significant recovery compared with the group of patients receiving placebo.

Conclusion

This study suggests that magnesium sulfate can be used as a safe and useful neuroprotective agent in acute ischemic stroke and lacunar stroke patients may represent a relevant and practical target population for agents with biological activity in white matter.     

Sex Differences in Stroke Incidence in a Portuguese Community-Based Study

Background and Aim

Stroke is a major health problem. Several studies reported sex differences regarding stroke. We aim to study this issue in an incidence stroke study.

Common carotid intima media thickness as a marker of clinical severity in patients with symptomatic extracranial carotid artery stenosis

Objectives

Increased common carotid artery intima-media thickness (CCA-IMT) is a risk factor for ischemic stroke and especially large vessel atherothrombotic infarction. However, the potential association of stroke severity with the intima-media thickening has not been previously studied. We sought to investigate the association between CCA-IMT and clinical severity of ischemic stroke in patients with symptomatic extracranial carotid artery stenosis (SCAS).

Patients and methods

Consecutive patients with acute, first-ever ischemic stroke and SCAS (50%–99%) were prospectively evaluated. All subjects underwent IMT measurements at the far wall of CCA. Stroke severity was assessed using the National Institute of Health Stroke Scale (NIHSS) on hospital admission and Barthel Ambulatory Index (BI) at hospital discharge.

Results

CCA-IMT was strongly correlated to NIH (Spearman's correlation coefficient: r = 0.546, p < 0.001) and BI (r = −0.450, p < 0.001) in the study population (n = 102). A 0.1 mm increase in CCA-IMT was independently associated with increasing NIHSS-scores on hospital admission (β: 0.510; p < 0.001) and decreasing BI-scores at hospital discharge (β: −0.483; p < 0.001) even after adjustment for demographic characteristics and cardiovascular risk factors. After including baseline stroke severity (NIHSS) in the multivariate linear regressions models evaluating early functional outcome, only NIHSS was independently related to BI (standardized linear regression coefficient: −0.776, p < 0.001), while the initial association between IMT and BI did not retain its statistical significance (β: −0.074, p = 0.276).

Conclusions

Increased CCA-IMT is independently associated with more severe stroke on admission in patients with SCAS.     

Peripheral vascular disease as remote ischemic preconditioning,for acute stroke

Objectives

Remote ischemic preconditioning (RIPC) is a powerful endogenous mechanism whereby a brief period of ischemia is capable of protecting remote tissues from subsequent ischemic insult. While this phenomenon has been extensively studied in the heart and brain in animal models, little work has been done to explore the effects of RIPC in human patients with acute cerebral ischemia. This study investigates whether chronic peripheral hypoperfusion, in the form of pre-existing arterial peripheral vascular disease (PVD) that has not been surgically treated, is capable of inducing neuroprotective effects for acute ischemic stroke.

Methods

Individuals with PVD who had not undergone prior surgical treatment were identified from a registry of stroke patients. A control group within the same database was identified by matching patient's demographics and risk factors. The two groups were compared in terms of outcome by NIH Stroke Scale (NIHSS), modified Rankin scale (mRS), mortality, and volume of infarcted tissue at presentation and at discharge.

Results

The matching algorithm identified 26 pairs of PVD-control patients (9 pairs were female and 17 pairs were male). Age range was 20–93 years (mean 73). The PVD group was found to have significantly lower NIHSS scores at admission (NIHSS ≤ 4: PVD 47.1%, control 4.35%, p < 0.003), significantly more favorable outcomes at discharge (mRS ≤ 2: PVD 30.8%, control 3.84%, p < 0.012), and a significantly lower mortality rate (PVD 26.9%, control 57.7%, p = 0.024). Mean acute stroke volume at admission and at discharge were significantly lower for the PVD group (admission: PVD 39.6 mL, control 148.3 mL, p < 0.005 and discharge: PVD 111.7 mL, control 275 mL, p < 0.001).

Conclusion

Chronic limb hypoperfusion induced by PVD can potentially produce a neuroprotective effect in acute ischemic stroke. This effect resembles the neuroprotection induced by RIPC in preclinical models.     

Less favorable neurological recovery after acute stroke in patients with hypercholesterolemia

Objectives

We aimed to investigate the effect of hypercholesterolemia on recovery after acute ischemic stroke.

Methods

Data of 3048 patients admitted for acute ischemic stroke from January to December 2009 were collected from the Stroke Registry in the Chang Gung Healthcare System. Baseline characteristics of patients with and without hypercholesterolemia were compared. The association of hypercholesterolemia with neurological severity and recovery was analyzed using multivariate logistic regression. The patients were then divided on the basis of age for subgroup analysis.

Results

The number of patients with and without a history of hypercholesterolemia was 474 (15.6%) and 2574 (84.4%), respectively. Univariate analysis showed that patients with hypercholesterolemia had a lower National Institutes of Health Stroke Scale (NIHSS) score on admission (p = 0.004). However, during hospitalization, these patients displayed less improvement in their NIHSS score (p = 0.002). These results remained significant in multivariate logistic regression analysis (p < 0.001 and p = 0.002, respectively). Subgroup analysis showed a similar association for hypercholesterolemia in both younger (age < 70) and older (age ≥ 70) age groups.

Conclusions

Acute ischemic stroke in patients with hypercholesterolemia was correlated with reduced severity on admission and less favorable recovery during hospitalization, regardless of age.     

Intravenous rt-PA in patients with ischaemic stroke and renal dysfunction

Objective

Renal dysfunction (RD) increases risk for ischaemic stroke (IS). The impact of RD on the effects of iv-thrombolysis in the Caucasian population has not been fully determined.

Aims

To evaluate the associations between RD and the outcome of iv-thrombolysis in Caucasian patients with IS.

Methods

The observational, multicentre study included 404 patients with IS who were treated with iv-thrombolysis. RD was defined as estimated glomerular filtration rate ≤60 ml/min/1.73 m². Outcome was assessed with modified Rankin Score at 3 months after the stroke onset.

Results

Medians baseline NIHSS score did not differ between groups of patients with and without RD (12.0 vs. 11.0 pts, p = 0.33). Unfavourable outcome was found in 52.1% of patients with and in 41.2% of patients without RD (p = 0.05), mortality was higher in patients with RD (29.9% vs. 14.3%, p < 0.001), and the presence of haemorrhagic transformation (HT) did not differ between the groups (17.1% vs. 17.1% respectively, p = 0.996). A multivariate analysis showed no impact of RD on the unfavourable outcome (OR 0.98; 95%CI 0.88–1.10), mortality (OR 0.92; 95%CI 0.81–1.05) or presence of HT (OR 1.03; 95%CI 0.90–1.18).

Conclusions

We found no impact of RD on the safety and efficacy of iv-thrombolysis in Caucasian patients with IS.     

Decompressive craniectomy after intravenous tissue plasminogen activator administration for stroke

Objective

Intravenous tissue plasminogen activator (IV tPA) is an approved treatment for acute ischemic stroke. However, the effects of decompressive craniectomy (DC) after IV tPA administration for ischemic stroke are still largely unknown. The aim of this study was to investigate the safety and outcomes of DC after IV tPA administration.

Methods

We retrospectively reviewed patients who underwent DC for malignant hemispheric infarction. We compared 20 patients who underwent DC after IV tPA administration with another 20 patients who underwent DC without prior IV tPA administration.

Results

The patient characteristics did not differ between the DC patients with and without prior IV tPA administration. New intracranial bleeding or worsening of pre-existing ICH occurred in two patients (10%) in each group. Furthermore, the rates of an mRS score of 4–6, 5 or 6, and 6 did not differ significantly between the two groups.

Conclusion

DC may be a safe and useful surgical procedure for space-occupying edema after IV tPA administration for acute stroke.     

Local intraarterial tirofiban after formation of anterograde flow in patients with acute ischemic stroke: Preliminary experience and short term follow-up results

Objective

Despite the risk of intracranial hemorrhage, combination therapy with intravenous recombinant tissue plasminogen activator and intraarterial mechanical thrombolysis can be effective for treatment of acute ischemic stroke. We investigated the feasibility and safety of intraarterial tirofiban following formation of anterograde flow after mechanical thrombolysis in acute ischemic stroke.

Methods

We analyzed data from consecutive patients with acute ischemic stroke, who underwent treatment with intraarterial thrombolysis. All patients were evaluated immediately and 7 days later by computed tomography scanning and magnetic resonance imaging scanning with magnetic resonance angiography. For clinical outcome analysis, we followed up the NIHSS score and modified Rankin Scale score during a period of 3 months.

Results

Sixteen patients underwent treatment. The mean baseline NIHSS score was 16.1 ± 4.4 points. 75.1% of patients showed angiographic improvement; 43.8% and 31.3% had complete and partial recanalization, respectively. 53.3% and 56.3% showed clinical improvement and favorable outcome at 24 h and 3 months, respectively. One patient had symptomatic intracranial hemorrhage.

Conclusions

Our results suggest that administration of local intraarterial tirofiban after anterograde flow formation is a viable treatment strategy for patients of acute ischemic stroke for reducing the risk of reocclusion after intraarterial thrombolysis.     

Characteristics of first ever ischemic stroke in the very elderly: profile of vascular risk factors and clinical outcome

Purpose

Age is the most significant non-modifiable risk factor for ischemic stroke (IS). With increasing expectancy of life, the majority of IS patients will be elderly subjects. We studied the epidemiological, clinical and rehabilitation features of patients aged ≥85 years with first-ever IS.

Methods

Demographic data, prevalence of risk factors, etiology of stroke, severity of neurological deficit, major complications and mortality rates were collected from a hospital-based stroke registry and compared between patients at the age of 65-84 and ≥85. Clinical assessment was performed by means of the National Institutes of Health Stroke Scale (NIHSS) and Modified Rankin Scale (mRS).

Results

Among 216 patients aged ≥85 years there was significantly higher proportion of a history of atrial fibrillation than in 128 patients at the age of 65-84 years and lower prevalence of hypertension, diabetes mellitus, hyperlipidemia and smoking. Large artery atherosclerosis was more frequently identified in the older patients (49% vs. 32%, p = 0.002). Although NIHSS scores on admission were lower in the older patients they were more disabled at discharge.

Conclusions

With respect to the patients aged <85 years very old IS patients showed different vascular risk factors profile, clinical and rehabilitation course. These findings suggest specializing stroke care in the very elderly.     

Normobaric oxygen therapy in acute ischemic stroke: A pilot study in Indian patients

Purpose:

Clinical and radiological assessment of effects of normobaric high-flow oxygen therapy in patients with acute ischemic stroke (AIS).

Materials and Methods:

Patients with anterior circulation ischemic strokes presenting within 12 h of onset, ineligible for intravenous thrombolysis, an National Institute of Health Stroke Scale (NIHSS) score of >4, a mean transit time (MTT) lesion larger than diffusion-weighted image (DWI) (perfusiondiffusion mismatch), and an evidence of cortical hypoperfusion on magnetic resonance imaging (MRI) were included into the trial. Active chronic obstructive pulmonary disease (COPD), requirement of >3/L min oxygen delivery to maintain SaO2 > 95%, rapidly improving neurological deficits, pregnancy, contraindications to MRI, or unstable medical conditions were excluded. The experimental group received humidified oxygen at flow rates of 10 L/min for 12 h. The NIHSS, modified Rankin Score (mRS), Barthel Index (BI) were measured at 0, 1, 7 day of admission and at 3 months follow-up. MRI with DWI/PWI was performed at admission, 24 h later and at 3 months follow-up.

Results:

Of 40 patients (mean age = 55.8 years ± 13.2) (range, 26–82), 20 patients were randomized to normobaric oxygen (NBO). The mean NIHSS in NBO and control groups were 14.25 and 12.7 at admission which decreased to 11.6 and 9.5 on the seventh day, and 9.4 and 9.05 at 3 months, respectively. The mean mRS (3.7/3.7) and BI (58.2/53.9) in NBO and control groups improved to 2/2.2 and 73.05/73.8 at the end of 3 months, respectively.

Conclusions:

NBO did not improve the clinical scores of stroke outcome in Indian patients with AIS.     

Impaired ability to shift weight onto the non-paretic leg in right-cortical brain-damaged patients

Background

: Stroke patients experience postural instability that can impede functional improvements in their gait. However, the precise functions of the dominant and non-dominant hemispheres in controlling static standing posture and weight-bearing remain unclear.

Objective

: To investigate differences in balancing ability between right-handed patients with right and left hemispheric lesions.

Methods

: Weight shifting was quantitatively evaluated to determine the ability of patients to control their balance in a static posture and during conscious weight shifting onto the paretic or non-paretic leg. Participants were enrolled from a consecutive series of stroke patients attending a rehabilitation program (n = 49; 31 male, 18 female; mean age 69.3 ± 9.4 years). Age-matched normal controls were recruited as volunteers (n = 12; 4 male, 8 female; mean age 67.9 ± 4.9 years).

Results

: Patients with cortical lesions in the right hemisphere were able to shift less weight onto the non-paretic leg than patients with cortical lesions in the left hemisphere (p < 0.05). There were no correlations between the existence of unilateral spatial neglect and the percentage of weight shifted onto the non-paretic leg, static standing posture (r = 0.27, p = 0.40) or dynamic standing posture (r = −0.37, p = 0.24). In contrast, there was a significant correlation between the percentage of weight consciously shifted onto the non-paretic leg and the existence of anosognosia (r = 0.74, p = 0.006), but not between static standing posture and anosognosia (r = −0.15, p = 0.63).

Conclusion

: Patients with right cortical hemispheric lesions were able to shift less body weight onto their non-paretic leg. These patients should be encouraged to practice shifting their weight towards their non-paretic leg to improve their balance.     

Mislocalization of tactile stimuli applied to the trunk in spatial neglect

Introduction

In patients with spatial neglect, body perception and representation are impaired – especially the projection of the anterior body midline in anterior space (the subjective “straight ahead”). However, data on more lateral body parts and the posterior body surface are scarce. We explored deviations of the perception of different body points located to the left or right of the midline and on the anterior and posterior body surfaces, and their lesion correlates in right hemisphere stroke patients.

Methods

Nine patients with neglect (diagnosed with paper and pencil and behavioural tests) were compared with six non-neglect patients and 13 healthy controls. The subjects had to use a mannequin to designate the body location that had been stimulated by a blunt pencil tip. Four horizontally arranged series of locations were traced on the anterior and posterior body surfaces at shoulder and navel levels. Each horizontal series comprised five equidistant test points, from left to right and corresponded to eleven labelled points on the mannequin. Patient errors were confronted to their anatomic lesions (MRI).

Results

We found a significant (p ≤ .05) rightward deviation of the left-side points and midpoint and a significant leftward deviation of the right-most point in neglect patients. Non-neglect patients and control subjects designated all the test points accurately. The body side (anterior or posterior) and the line (shoulder or navel) did not influence performance. Controls showed a definite reduction in variability for the midline points, which disappeared in neglect patients who showed a severe global increase of this variability. Errors depended on lesions centred on the intraparietal sulcus.

Conclusions

These observations were compatible with a complex bias in body perception–representation extending to various lateral body points, with a left to right gradient. The right parietal cortex likely participates in processing such information.