Full Characterization of Multiphase, Multimorphological Kinetics in Flow-Induced Crystallization of IPP at Elevated Pressure.

Understanding the complex crystallization behavior of isotactic polypropylene (iPP) in conditions comparable to those found in polymer processing, where the polymer melt experiences a combination of high shear rates and elevated pressures, is key for modeling and therefore predicting the final structure and properties of iPP products. Coupling a unique experimental setup, capable to apply wall shear rates similar to those experienced during processing and carefully control the pressure before and after flow is imposed, with in situ X-ray scattering and diffraction techniques (SAXS and WAXD) at fast acquisition rates (up to 30 Hz), a well-defined series of short-term flow experiments are carried out using 16 different combinations of wall shear rates (ranging from 110 to 440 s-1) and pressures (100-400 bar). A complete overview on the kinetics of structure development during and after flow is presented. Information about shish formation and growth of α-phase parents lamellae from the shish backbones is extracted from SAXS; the overall apparent crystallinity evolution, amounts of different phases (α, ß, and γ), and morphologies developing in the shear layer (parent and daughter lamellae both in α and γ phase) are fully quantified from the analysis of WAXD data. Both flow rate and pressure were found to have a significant influence on the nucleation and the growth process of oriented and isotropic structures. Flow affects shish formation and the growth of α-parents; pressure acts on relaxation times, enhancing the effect of flow, and (mainly) on the growth rate of γ-phase. The remarkably high amount of γ-lamellae found in the oriented layer strongly indicates the nucleation of γ directly from the shish backbone. All the observations were conceptually in agreement with the flow-induced crystallization model framework developed in our group and represent a unique and valuable data set that will be used to further validate and implement our numerical modeling, filling the gap for quantitatively modeling crystallization during complicated processing operations like injection molding.

Prognostic factors in multiple sclerosis rehabilitation.

AIM: The aim of our study was to evaluate the effectiveness of inpatient multidisciplinary rehabilitation treatment in multiple sclerosis (MS) and identify reliable prognostic factors. METHODS: Two hundred patients were enrolled for this study (65% females), with a mean age of 49.77+11.32 years and a mean disease duration of 17.33+10.15 years. RESULTS: The results of rehabilitation were assessed in the whole sample, as well as by comparing three subgroups, divided according to their basal Expanded Disability Status Scale of Kurtzke (EDSS) score: a ''mild'' group (EDSS score 2-5.5), a ''moderate'' group (EDSS 6-6.5), and a ''severe'' group (EDSS 7-8.5). All three subgroups of patients showed a significant improvement in functional status in both the Barthel Index and Rivermead Mobility Index (Wilcoxon Test) at discharge. However the effectiveness observed in patients with mild and moderate MS in both ADL and mobility was significantly higher than that observed in patients with the severe form. CONCLUSIONS: A multidisciplinary rehabilitative approach should be recommended for patients with a short disease duration and a relatively moderate disability.

Functional transcranial Doppler assessment of cerebral blood flow velocities changes during attention tasks.

BACKGROUND AND PURPOSE: Aim of our study was to evaluate cerebral hemodynamic changes during performance of attention tasks and to correlate them with reaction time (RT) and percentage of right answers. METHODS: Mean flow velocity (MFV) in middle cerebral arteries was monitored in 30 subjects by transcranial Doppler during tonic alertness, phasic alertness, focused and divided attention tasks. RESULTS: Mean flow velocity increase was significantly higher during divided attention with respect to other tasks (P < .001). MFV increase was higher in the right than in the left side (P < .001). Asymmetry during attention tasks resulted significantly higher than that observed in tonic alertness condition. RT was increased during focused attention tasks (P < .001 vs. both alert tasks), with further increase during divided attention tasks (P < .001 vs. focused attention task). RT was inversely related to MFV increase only during tonic alertness (P = 0.012 for left side; P = 0.008 for right side). During the divided attention tasks, an association was found between MFV increase and correct answers (r = 0.39, P = 0.033). CONCLUSIONS: These data show a relationship between RT, correct answers and changes in blood flow velocity and suggest that this method of cerebral blood flow investigation could be a useful approach during assessment of patients with attention deficit.

Pain in multiple sclerosis: a clinical and instrumental approach.

BACKGROUND: Pain is a frequent and disabling symptom in multiple sclerosis (MS) patients. In this study we assess the frequency and intensity of pain, as well as its impact on the quality of life and activities of daily living, in a sample of MS patients. METHODS: One hundred and twenty eight MS patients underwent a neurological examination, a structured interview designed to assess pain, and a Medical Outcome 36-item Short Form Health Survey. Functional status was assessed by means of the Barthel Index (BI) and Rivermead Mobility Index. We also assessed the presence of depression, by means of the Montgomery and Asberg Depression Rating Scale, and fatigue, by means of the Fatigue Severity Scale. An algometer was used to measure thermal and discomfort thresholds in all of the patients and a group of 61 age- and sex-matched healthy subjects. RESULTS: Pain was present in 61 patients. No differences were found between patients with and those without pain in disease duration, disease form or Expanded Disability Status Scale and its functional systems. Patients with pain had a lower vitality score (p = 0.008), mental health score (p = 0.03) and physical (p < 0.001) and mental composite scores (p = 0.01) than patients without pain. Furthermore, there was a significant difference between patients with and those without pain in the BI (p = 0.04). Both thermal and discomfort thresholds, as assessed by means of the algometer, were statistically lower in MS patients than in controls, whereas no difference was observed between patients with and those without pain. There was a statistically significant improvement in the thermal threshold in patients with pain who were treated pharmacologically when compared with those who were not treated (p = 0.049). CONCLUSION: The results of this study provide further evidence of the negative impact that the presence of pain has on both the quality of life and activities of daily living in MS patients. The lower thermal and discomfort thresholds observed in our MS patients, compared with controls, may represent a predisposition to develop pain during the course of the disease.

Cerebral blood flow velocity changes during meaningful and meaningless gestures--a functional transcranial Doppler study.

The aim of the study was to use functional transcranial Doppler to investigate the possibility of revealing different activation patterns during healthy subjects' performance of meaningful and meaningless actions. Mean flow velocity (MFV) changes were recorded in middle cerebral arteries (MCAs) of 26 normal subjects during a rest phase and during performance of meaningful and meaningless actions. The meaningful task consisted of pouring sugar into a cup with a teaspoon. The meaningless action was an arm movement similar to that necessary for pouring sugar in a cup but without any tool and thus without a goal. Performing actions with or without meaning was associated with different patterns of MFV changes, as documented by the triple interaction condition x performing arm x side of recording [F(1, 25)=10.977; P=0.003]. During the meaningful action, MFV in MCAs increased significantly more than during the meaningless action. During the meaningless action, the MFV increase was significantly higher in the contralateral than in the ipsilateral MCA to the arm performing the task and the meaningful action determined a bilateral MFV increase only when the task was performed with the left arm. When the same task was performed with the right arm, the MFV increase was significantly higher in the contralateral than in the ipsilateral MCA. These findings suggest that the content of an action can influence MFV changes and further confirm the usefulness of transcranial Doppler in neuropsychological investigation.

Prognostic factors in multidisciplinary rehabilitation treatment in multiple sclerosis: an outcome study.

The aim of this outcome study was to evaluate the effectiveness and prognostic factors of inpatient multidisciplinary rehabilitation treatment in patients with multiple sclerosis (MS). We analysed 230 consecutive inpatients with MS admitted to an MS rehabilitation ward who followed an individualized, goal-oriented, multidisciplinary rehabilitation program. Every patient was submitted to a neurological examination and evaluated by means of Kurtzke's Expanded Disability Status Scale (EDSS), with its functional systems (FS), Barthel Index (BI) and the Rivermead Mobility Index (RMI). We observed an effectiveness (percentage of potential improvement achieved during rehabilitation) of nearly 16% on BI and 8% on RMI, corresponding to an improvement in 124 patients (54%) on BI and 113 patients (49%) on RMI. Basal EDSS (beta = -0.32, P <0.001), cognitive status (beta = -0.15, P <0.05) and disease duration (beta = -0.13, P <0.05) were negatively associated with effectiveness of treatment on BI (adjusted R2 = 0.176), whereas effectiveness on RMI was correlated only with the EDSS score (beta = -0.34, P <0.001, adjusted R2 = 0.113). In the logistic regression analysis, the absence of severe sphincteric disturbances was correlated with the probability of improvement on BI that was nearly twice as high (OR =2.25, 95% CI 1.24-4.08) as that of other patients. Moreover, patients without severe cognitive deficits showed a similar probability (OR =2.37, 95% CI 1.05-5.33) of improvement on RMI. The results of this study provide further evidence that intensive multidisciplinary rehabilitation in MS is effective in the majority of MS patients and that early treatment may favour functional recovery.

Emotional processing in Parkinson's disease. A study using functional transcranial doppler sonography.

This study evaluated the use of transcranial Doppler ultrasonography for detecting selective changes in cerebral blood flow velocity during emotional processes. The aim was to investigate the possibility of obtaining functional information on the neuropsychology of emotions in patients with Parkinson's disease (PD). For this reason, blood flow velocity changes were investigated in both middle cerebral arteries (MCA) during a rest condition and when viewing non emotional (tasks 1 and 3) and emotional (task 2) slide sequences. The study included 12 PD patients and 12 healthy subjects. All patients were in treatment with levodopa or dopamine agonist. Investigation of PD patients was performed during an on-phase. The three tasks produced significantly different effects on the right and left side in the PD patients compared with the control group. During the two non emotion-related tasks the increase of mean flow velocity (MFV) compared with the basal values was similar in the two middle cerebral arteries in both groups [(PD Patients: Task 1: left MCA = 3.95 % 2.2, Right MCA = 4.33 % +/- 2.3, Task 3: left MCA = 3.04 % +/- 1.9, Right MCA = 2.71 % +/- 2.2) (control group: Task 1: left MCA = 4.57 % +/- 1.4, Right MCA = 4.46 % +/- 1.7, Task 3: left MCA = 2.32 % +/- 0.9, Right MCA = 2.52 % +/- 1.2)] The negative emotional task was accompanied by a significantly higher increase in the right (10.53 % +/- 3.2) than in the left middle cerebral artery (4.52 % +/- 1.51) only in the control group. The PD patients showed a bilateral and symmetrical increase of MFV (left MCA = 4.28 % +/- 2.3 and right MCA 5.77 % +/-3.8). To determine whether there was a dysfunction in cerebrovascular reactivity and a deficit in the ability to activate both hemispheres in response to non emotion-related stimuli in the PD patients, the protocol study included a cerebrovascular reactivity test to apnea, a motor task (thumb-to-finger opposition), a cognitive task (word fluency and visual discrimination of objects), performed by both patients and controls. The pattern of MFV changes during these tasks was not statistically significantly different in the two experimental groups. In order to evaluate the possible influence of drug treatment on cerebrovascular reactivity, seven patients were also evaluated during an off-phase, after a 48-hour wash-out period. Changes in MFV during every task were similar to that observed during the on-phase. These findings show the possibility of obtaining specific functional information from bilateral transcranial Doppler and suggest the selective and specific deficit of PD patients in emotional processing.

Prognostic factors in stroke rehabilitation: the possible role of pharmacological treatment.

OBJECTIVES: The aim of the present study was to determine the impact of commonly used and potentially detrimental drugs on rehabilitation results and to clarify their role as prognostic factors. MATERIAL AND METHODS: The study included 154 patients admitted to a rehabilitation hospital for sequelae of a first stroke. Multivariate analyses were performed using effectiveness of treatment, evaluated by both the Barthel Index (BI) and the Rivermead Mobility Index (RMI) and low response on both of these indexes as dependent variables. Independent variables were medical, demographic and pharmacological factors. RESULTS: The use of detrimental drugs was negatively associated with effectiveness on both BI and RMI. Severity of stroke (Canadian Neurological Scale score at admission) and hemineglect were the other negative prognostic factors that significantly entered the analyses. On the other hand, the presence of Broca's aphasia positively influenced the recovery, essentially due to prolonged length of stay. The presence of detrimental drugs and hemineglect were associated with a higher risk of low response on both BI and RMI. CONCLUSION: These findings confirm that the use of some drugs can influence rehabilitation results. Therefore, the choice of pharmacological treatment of stroke patients should be carefully evaluated by considering the potential detrimental effects of some drugs commonly used for the treatment of coincidental medical conditions.

Post-stroke depression, antidepressant treatment and rehabilitation results. A case-control study.

The aim of this study was to assess the specific influence of poststroke depression (PSD) on both basal functional status and rehabilitation results. We performed a case-control study in 290 stroke inpatients, matched for age (+/-1 year) and onset admission interval (+/-3 days) and divided in two groups according to the presence (PSD+) or absence (PSD-) of PSD. All PSD+ patients were treated with antidepressants (AD), mainly with fluoxetine. PSD+ patients, despite similar severity of stroke, showed greater disability in coping with activities of daily living (ADL) on admission and greater disability both in ADL and mobility at discharge than PSD- patients. Although both groups exhibited similar average functional improvement during rehabilitation, PSD- patients were nearly twice as likely to show excellent recovery both on ADL and mobility as PSD+ patients (OR = 1.95, 95% CI = 1.01-3.75 and OR = 2.23, 95% CI = 1.14-4.35, respectively). All AD drugs improved depressive symptoms. Few relevant side effects were observed: fluoxetine was discontinued in 2 patients because of insomnia and in 2 patients because of nausea; paroxetine was stopped in 1 patient because of nausea and dry mouth. Our results confirm the unfavorable influence of PSD on functional outcome, despite pharmacological treatment.

Effect of collateral blood flow and cerebral vasomotor reactivity on the outcome of carotid artery occlusion.

BACKGROUND AND PURPOSE: Evidence suggests that an alteration in cerebral hemodynamics plays a relevant role in the occurrence of stroke in patients with carotid occlusion. The purpose of the present study was to evaluate the relationships among baseline characteristics, type and number of collateral pathways, cerebral vasomotor reactivity (VMR), and outcome of patients with carotid occlusion. METHODS: One hundred four patients with symptomatic or asymptomatic internal carotid artery occlusion were followed up prospectively for a median period of 24 months. Cerebral VMR to apnea was calculated with transcranial Doppler ultrasonography by means of the breath-holding index (BHI) in the middle cerebral arteries. The patency of the 3 major intracranial collateral vessels was also evaluated. RESULTS: During the follow-up period, 18 patients experienced an ischemic stroke ipsilateral to internal carotid artery occlusion. Among factors considered, only older age, number of collateral pathways, and BHI values in the middle cerebral artery ipsilateral to the occluded side were significantly associated with the risk of ipsilateral stroke (P<0.001, P=0.008, and P<0.001, respectively; multiple Cox regression analysis). A normal VMR and favorable prognosis characterized patients with full collateral development; in this group, no patient experienced an ischemic event. On the other hand, an impaired VMR and increased probability of experiencing a stroke were found in patients without collateral pathways; the annual risk of ipsilateral stroke in this group was 32.7%. Patients with 1 or 2 collateral pathways showed a different VMR ranging from normal to strongly reduced BHI values. The ipsilateral stroke event risk was 17.5% in patients with 1 collateral vessel and 2.7% in patients with 2 collateral pathways. In this case, the risk of cerebrovascular events occurring during the follow-up period was significantly related to VMR. CONCLUSIONS: These data suggest that cerebral hemodynamic status in patients with carotid occlusive disease is influenced by both individual anatomic and functional characteristics. The planning of strategies to define the risk profile and any attempt to influence patients' outcome should be based on the evaluation of the intracranial hemodynamic adaptive status, with particular attention to the number of collateral vessels and the related VMR.

Changes in cerebral blood flow induced by passive and active elbow and hand movements.

Transcranial Doppler ultrasonography (TCD) has been widely used to obtain information about changes in cerebral perfusion during motor activity after stroke. This type of application is greatly limited when severe motor deficits are present that impede the performance of an active motor task. In this study, we explored the effect of performing passive arm movements on cerebral perfusion. Twenty healthy subjects were investigated. A bilateral TCD monitoring of the middle cerebral artery (MCA) flow velocity was performed during the following experimental conditions: 1-min of active and passive flexion-extension elbow movement and 1-min of active and passive dorsal extension hand movement. Each task was performed with both left and right arms. The percentage increase in flow velocity from rest to task performance was calculated. Each task produced a significantly greater increase in mean flow velocity in the contralateral MCA with respect to the ipsilateral. When comparing the effect of passive and active tasks, no significant difference in mean flow velocity changes recorded in the ipsilateral and the contralateral MCA was detected regarding either elbow or hand movements. These findings demonstrate the possibility of obtaining information about changes in hemispheric cerebral perfusion during passive movements involving elbow and hand. This type of application deserves further attention in the study of cerebral functional changes following cerebral lesions.

Mobility status after inpatient stroke rehabilitation: 1-year follow-up and prognostic factors.

OBJECTIVES: To evaluate the stability of mobility status achieved by stroke patients during hospital rehabilitation treatment over time and to identify reliable prognostic factors associated with mobility changes. DESIGN: Follow-up evaluation in consecutive first-ever stroke patients 1 year after hospital discharge. Multiple logistic regressions were used to analyze increases and decreases in Rivermead Mobility Index (RMI) scores (dependent variables) between discharge and follow-up. Independent variables were medical, demographic, and social factors. SETTING: Rehabilitation hospital. PATIENTS: A cohort of 155 patients with sequelae of first stroke, with a final sample of 141. MAIN OUTCOME MEASURES: Mobility status at 1-year follow-up, as measured by the RMI, and odds ratios (OR) for improvement and decline in mobility. RESULTS: Functionally, 19.9% improved the mobility levels achieved during the inpatient rehabilitation treatment; levels of 42.6% worsened. Patients with global aphasia (OR = 5.66; 95% confidence interval [CI], 1.50-21.33), unilateral neglect (OR = 3.01; 95% CI, 1.21-7.50), and age 75 years or older (OR = 5.77; 95% CI, 1.42-23.34) had a higher probability of mobility decline than the remaining patients. Postdischarge rehabilitation treatment (PDT), received by 52.5% of the final sample, was significantly and positively associated with mobility improvement (OR = 5.86; 95% CI, 2.02-17.00). Absence of PDT was associated with a decline in mobility (OR = 3.73; 95% CI, 1.73-8.04). CONCLUSIONS: In most cases, mobility status had not yet stabilized at hospital discharge. PDT was useful in preventing a deterioration in mobility improvement achieved during inpatient treatment and in helping increase the likelihood of further mobility improvement.

Correlation of cerebral hemodynamic changes during mental activity and recovery after stroke.

OBJECTIVE: To investigate the correlation between changes in cerebral functional activity during mental engagement and the potential for neurologic recovery after stroke. BACKGROUND: Transcranial Doppler ultrasonography (TCD) makes it possible to detect the dynamic adjustment of cerebral perfusion related to functional neuronal changes. METHODS: TCD monitoring of flow velocity changes in the middle cerebral artery of 29 ischemic stroke patients was performed during an object recognition task. The study took place within 4 weeks from stroke onset. Based on recovery occurring after 2 months, the patients were divided into four groups depending on the side of hemispheric lesion and the presence or absence of neurologic recovery. Ten healthy subjects served as control subjects. RESULTS: During the recognition task, control subjects showed a bilateral increase in flow velocity with respect to the rest phase (right side, 7.02 +/- 1.3%; left side, 6.65 +/- 1. 1%), with no side-to-side difference. In patients who experienced recovery, a similar pattern of bilateral activation was observed, irrespective of the side of the lesion. Conversely, in patients with no recovery, the increase of flow velocity was significantly higher on the side contralateral to the brain lesion (p < 0.0001) with respect to the lesion side. Performance during the recognition task was comparable in the four groups of patients. CONCLUSIONS: These findings suggest that satisfactory recovery from a neurologic deficit requires the persistence of functional activity in the damaged hemisphere despite the presence of an anatomic lesion. The possibility of obtaining early prognostic indications with TCD may be relevant for an early selection of patients with the best probability of benefiting from rehabilitation therapy.

Early versus delayed inpatient stroke rehabilitation: a matched comparison conducted in Italy.

OBJECTIVE: To assess the specific influence of onset-admission interval (OAI) on rehabilitation results. DESIGN: A case-control study in consecutive stroke inpatients, enrolled in homogeneous subgroups, matched for age (within 1 year) and Barthel Index (BI) score at admission, and different for OAI to the rehabilitation ward. The short OAI group began rehabilitation treatment within the first 20 days from stroke, medium OAI group between days 21 and 40, and long OAI between days 41 and 60. SETTING: Rehabilitation hospital. PATIENTS: One hundred forty-five patients with sequelae of first stroke. MAIN OUTCOME MEASURES: Efficiency (average increase in BI per day), effectiveness (proportion of potential improvement achieved during rehabilitation) of treatment, and percentage of low- and high-response patients, calculated on BI, were evaluated. Odds ratios (ORs) of dropouts and of poor and excellent therapeutic response were also quantified. RESULTS: The short OAI subgroup had significantly higher effectiveness of treatment than did the medium (p < .05) and the long OAI groups (p < .005). Beginning treatment within the first 20 days was associated with a significantly high probability of excellent therapeutic response (OR = 6.11; 95% confidence interval [CI], 2.03-18.36), and beginning later was associated with a similar risk of poor response (OR = 5.18; 95% CI, 1.07-25.00). On the other hand, early intervention was associated with a five times greater risk of dropout than that of patients with delayed start of treatment (OR = 4.99; 95% CI, 1.38-18.03). The three subgroups were significantly (p < .05) different regarding the percentage of low and high responders. CONCLUSION: Our results showed a strong association between OAI and functional outcome.

Impaired cerebral vasoreactivity and risk of stroke in patients with asymptomatic carotid artery stenosis.

CONTEXT: Standards for treating patients with asymptomatic carotid artery stenosis have been difficult to establish because of the lack of evidence for factors influencing these patients' prognoses. However, preliminary evidence suggests that an alteration in cerebral hemodynamic function may play a relevant role in the occurrence of stroke in patients with carotid artery disease. OBJECTIVE: To investigate the relationship between cerebrovascular reactivity to hypercapnia and cerebrovascular events in patients with severe unilateral asymptomatic carotid artery stenosis. DESIGN AND SETTING: Prospective, blinded longitudinal study conducted in an outpatient neurovascular department in Italy between June 1996 and April 1998, with a median follow-up of 28.5 months. PATIENTS: Ninety-four patients with asymptomatic carotid artery stenosis of at least 70% (74 men; mean age, 71 years). MAIN OUTCOME MEASURES: Subsequent occurrence of cerebral ischemic events (transient ischemic attack or stroke) or death, analyzed by cerebrovascular reactivity to hypercapnia (measured by transcranial Doppler ultrasonography and calculated by the breath-holding index values in the middle cerebral arteries). RESULTS: The overall annual rate for all ischemic events was 7.9%. Seventeen patients (18%) had ischemic events, all but 1 of which were ipsilateral to the carotid artery stenosis. Among factors considered, only lower breath-holding index values in the middle cerebral artery ipsilateral to carotid artery stenosis were significantly associated with the risk of an event (hazard ratio, 0.09; 95% confidence interval, 0.02-0.38; P=.001, by multivariate analysis). Based on data from previously studied healthy subjects, the cutoff of the breath-holding index for distinguishing between impaired and normal cerebrovascular reactivity was determined to be 0.69. Using this cutoff, the annual ipsilateral ischemic event risk was 4.1% in patients with normal and 13.9% in those with impaired breath-holding index values. CONCLUSIONS: These results suggest a link between impaired cerebrovascular reactivity and the risk of ischemic events ipsilateral to severe asymptomatic carotid stenosis.

One-year follow-Up in stroke patients discharged from rehabilitation hospital.

This study was designed to evaluate functional status at a 1-year follow-up in consecutive first-stroke patients after discharge from rehabilitation hospital and to identify reliable prognostic factors associated with changes in their abilities. Functional evaluation was made of consecutive patients 1 year after discharge to their own homes. Two multiple logistic regressions (forward stepwise) were performed using both improvement and worsening of the Barthel Index score between discharge and follow-up as dependent variables. Independent variables were medical, demographic and social factors. The final sample included 157 out of 172 patients. During the follow-up, 10 patients (5.81%) died because of a new cerebrovascular event, 1 patient died of myocardial infarction, 2 patients had new strokes and 2 fractured their paretic legs. Functionally, 43.3% of the patients maintained the level they achieved during inpatient rehabilitation treatment, 23.6% improved and the remaining 33.1% worsened. Patients with hemineglect and aged >/=65 years had a higher probability of functional worsening (odds ratio, OR = 3.77, 95% confidence interval, CI = 1.42- 10.0 and OR = 3.93, 95% CI = 1. 72-8.95, respectively). Postdischarge rehabilitation (performed for 46.5% of the final sample) was significantly and positively associated with functional improvement (OR = 7.23, 95% CI = 2.89-18. 05), and its absence with functional worsening (OR = 12.32, 95% CI = 4.47-37.01). In conclusion, in nearly half of the cases, functional status was still not stabilized at the time of discharge from the rehabilitation hospital. Postdischarge outpatient treatment was useful for preventing worsening of the functional ability achived during inpatient treatment and increased the possibility of further functional improvement. Age >/=65 years and hemineglect were predictors of functional worsening at follow-up.

Patterns of cerebrovascular reactivity in patients with carotid artery occlusion and severe contralateral stenosis.

There is evidence suggesting that among other factors, an alteration in cerebral hemodynamics plays a relevant role in the occurrence of strokes in patients with carotid disease. The purpose of this study was to investigate patterns of cerebrovascular reactivity in patients with internal carotid occlusion and severe contralateral carotid stenosis and their relationship with symptomatology. Using transcranial Doppler ultrasound, cerebrovascular reactivity to hypercapnia in middle cerebral arteries was evaluated with the breath-holding index (BHI) in 42 patients with internal carotid occlusion and severe contralateral carotid stenosis and in 40 control subjects. A significant decrease of BHI on the occluded side was observed in symptomatic patients with respect to asymptomatic ones (0.12+/-0.1 vs. 0.75+/-0.4, P<0.0001) and with respect to the control group (1.11+/-0.1, P<0.0001). The difference was also significant between asymptomatic patients and controls (P<0.0001). Breath-holding values on the stenotic side were significantly higher (P<0.0001) in asymptomatic patients (1.01+/-0.2) with respect to symptomatic ones (0.39+/-0.1). A significant difference (P<0.0001) was also present between controls and symptomatic patients. The pattern of cerebrovascular reactivity in patients with severe bilateral carotid steno-occlusive disease seems to be strictly dependent on the presence of previous symptoms. Further studies are needed to investigate whether the study of cerebral hemodynamics in patients with bilateral carotid artery disease is important for planning therapeutic strategies.

Cerebrovascular reactivity in carotid artery occlusion: possible implications for surgical management of selected groups of patients.

OBJECTIVES: The aim of this study was to use transcranial Doppler ultrasonography to investigate cerebrovascular reactivity to hypercapnia in the middle cerebral arteries of patients with carotid occlusion with different outcomes. PATIENTS AND METHODS: Cerebrovascular reactivity to hypercapnia was calculated with the breath-holding index (BHI). Patients with unilateral carotid occlusion were divided as follows: asymptomatic (20 patients), transient ischemic attack (TIA) (20 patients), minor (20 patients) and major stroke (14 patients). Values of BHI homolateral to the carotid occlusion were compared with those of 25 healthy subjects and 34 stroke patients without significant carotid stenosis. RESULTS: BHI values were comparable in healthy controls, non stenotic stroke patients and asymptomatic occluded patients. BHI values of patients with symptomatic occlusion were significantly lower than those of the above-mentioned groups (P<0.0001). Moreover, the reduction of BHI was significantly associated with the extent of the neurological impairment. In fact, BHI values were significantly higher in TIA than in minor and major stroke (P<0.0001) and in minor than in major stroke patients (P<0.02). Finally, we found that a BHI value homolateral to carotid occlusion of 0.69 can be considered the cut-point for distinguishing between symptomatic and asymptomatic patients. CONCLUSION: Prospective studies are needed to demonstrate if the presence of this threshold value may help in selecting a subset of patients with asymptomatic carotid occlusion or with transient or mild neurological deficit with the highest probability of benefiting from surgical therapy.

Does the antimigraine action of flunarizine involve the dopaminergic system? A clinical-neuroendocrinological study.

We have investigated the prolactin response to bromocriptine (BRC), a D2 dopamine receptor agonist in migrainous women before and after treatment with flunarizine. We evaluated whether this test was predictive of therapeutic efficacy of flunarizine treatment and whether the therapeutic response to flunarizine treatment was related to its effect on dopaminergic system at tuberoinfundibular level. Ten migrainous women underwent a BRC test in the late follicular phase before and after 1 and 3 months of treatment with flunarizine 10 mg at bedtime. Blood samples of prolactin (PRL), growth hormone, follicle-stimulating hormone, luteinizing hormone, estradiol and progesterone were taken at basal condition. PRL was also evaluated 1 and 2 h after BRC (2.5 mg) administration. Each patient kept a daily headache diary for 1 month prior to the test and throughout the study. The level of PRL inhibition after BRC administration, observed before flunarizine treatment, was not predictive of the therapeutic response observed after 1 and 3 months of treatment. The effect of flunarizine on PRL level was not related to the therapeutic efficacy of the drug. These data suggest that flunarizine does not attenuate the activity of dopaminergic neurons in migrainous patients, and that the antimigraine effect of flunarizine does not seem related to its action on dopaminergic system at least at tuberoinfundibular level.

Emotion-related cerebral asymmetry: hemodynamics measured by functional ultrasound.

This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries (MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres. During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1: left MCA = 3.27 +/- 1.9%; right MCA = 3.63 +/- 2.1%; task 3: left MCA = 2.42 +/- 0.7%; right MCA = 2.56 +/- 1.3%); the negative emotional task was accompanied by a significantly higher increase in the right (11.31 +/- 1.6%) than in the left MCA (4.72 +/- 3.7%; analysis of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler ultrasound and suggest the involvement of the right hemisphere in emotional processing.