Risk Factors Associated With Peripheral Neuropathy in Heart Failure Patients Candidates for Transplantation

INTRODUCTION

Peripheral neuropathy can affect patients with heart failure, though its prevalence is unknown. After heart transplantation, it can influence the postoperative course and quality of life, but screening for neuromuscular disease is not routinely performed.

OBJECTIVE

The aim of this study was to identify the factors associated with neuropathy in a population of patients with heart failure who are candidates for heart transplantation.

STUDY DESIGN

Data regarding patients' clinical history, including recent hospitalizations, were collected. All patients underwent a complete neurological examination and a neurophysiological protocol including nerve conduction studies and concentric needle electromyography.

RESULTS

Thirty-two patients were included in the study, and neuropathy was diagnosed in 10 (31.3%). Neuropathy was associated with the number of admissions ( P = .023; odds ratio [OR]: 1.96) and the total number of days of hospitalization in the year prior to inclusion in the study ( P = .010; OR: 1.03). The majority of hospitalizations occurred in the step-down unit (85%), with acute heart failure the leading cause of admission (42%).

CONCLUSIONS

This study shows that neuropathy is frequent in patients with advanced heart failure and that hospitalization for cardiac care, also in the absence of intensive care, is a marker of high risk of neurologic damage. These data can help physicians in selecting and managing candidates for transplantation and can guide decisions on the best immunosuppressive regimen or rehabilitation strategy.

Reduced Neuron-Specific Enolase Levels in Chronic Severe Traumatic Brain Injury

Growing evidence suggests that pathophysiological mechanisms leading to neurodegeneration and neuronal loss take place during the chronic phase of a severe traumatic brain injury (TBI). In this study we evaluated a well-established marker of brain injury, the neuron-specific enolase (NSE), in the serum of 51 patients with severe TBI (86% males, mean age 33.8 ± 11.1 years). All patients' samples were available from a previous study and the mean time between TBI and blood sample collection was 23.2 ± 31.5 months (28 patients were evaluated within 12 months of TBI and 23 patients were evaluated ≥12 months after TBI). Patients' NSE levels were compared with those obtained from 30 age and sex-matched healthy controls (87% males, 33.7 ± 11.3 years). We found that NSE levels were significantly lower in patients (median 3.2 ng/mL; 25th, 75th percentile 2.5, 5.1) than in healthy controls (median 4.1 ng/mL; 25th, 75th percentile 3.1, 7.5) (p = 0.026). This finding was mainly driven by data from the chronic patients, that is, those who experienced their TBI at least 12 months before the evaluation. Indeed, these patients had significantly lower NSE levels (median 2.6 ng/mL; 25th, 75th percentile 1.9, 4) than healthy controls (p < 0.01). On the other hand, NSE levels evaluated in patients <12 months from TBI (median 3.9 ng/mL; 25th, 75th percentile 2.8, 5.7) did not significantly differ from controls (p = 0.3). These findings possibly reflect a progressive brain atrophy with reduced baseline NSE release in the chronic phase of a severe TBI.

Choline-PET/CT in the Differential Diagnosis Between Cystic Glioblastoma and Intraparenchymal Hemorrhage

OBJECTIVE

Glioblastoma multiforme (GBM) represents the most common and malignant glioma, accounting for 45%-50% of all gliomas. The median survival time for patients with glioblastoma is only 12-15 months after surgical, chemioterapic and radiotherapic treatment; a correct diagnosis is naturally fundamental to establish a rapid and correct therapy. Non-invasive imaging plays a pivotal role in each phase of the diagnostic workup of patients with suspected for diagnosis. The aim of this case report was to describe the potential clinical impact of 18F-fluorocholine (FCH) PET/CT in the assessment of a cystic GBM mimicking a spontaneous hemorrhage.

METHODS

a 57 years-old male with intraparenchymal hemorrhage at CT imaging initially in reduction ad serial imaging and suspected right fronto-temporo-parietal lesion at MRI underwent dynamic and static (60' after tracer injection) FCH PET/CT of the brain.

RESULTS

FCH PET/CT showed rapid tracer uptake after few second from injection at dynamic acquisition and consequent incremental mild uptake at static imaging after 60 minutes at the level of oval formation in the right cerebral hemisphere characterized by annular and peripheral high metabolic activity. The central region of the lesion was characterized by the absence 18F-FCH uptake most likely due to blood component. The patient underwent surgery for tumor removal; the histopathological examination confirmed the suspect of GBM. Chemo-radiotherapic adjuvant protocol according to Stupp protocol was therefore administrated; to date the patient is alive without any progression disease at 5 months from treatment.

CONCLUSION

In this case report FCH PET/CT represented the final diagnostic technique to confirm the suspicious of a cystic GBM. Our case demonstrated the potential role of 18F-FCH PET/CT for discrimination of higher proliferation area over intraparenchymal hemorrhage, supporting the potential use of this imaging biomarker in surgical or radiosurgical approach. Obviously, further prospective studies are needed to confirm this role and to exactly define possible routinely applications.

A New Standardization of the Bells Test: An Italian Multi-Center Normative Study

Objective: The Bells Test is a cancelation task that is widely used for the diagnosis of unilateral spatial neglect (USN). With the aim of fostering more reliable use of this instrument, we set out to develop new norms adjusted for the possible influence of age, gender and education. We worked on the original version of the test.

Methods: Normative data were collected from 401 healthy participants aged between 20 and 80 years. Individual factors that could affect performance (i.e., gender, age, and years of education) were considered. We computed several indices on the Bells Test including an asymmetry score, an accuracy score and execution time. Multiple regression analyses (for time measures) and generalized linear models (for accuracy measures) were used to check for the influence of individual predictors of performance on the Bells Test.

Results: Data indicated a significant influence of age on the accuracy score and execution time variables and a marginally significant effect of education on the accuracy score variable. Wherever appropriate, cut-offs are provided for the three dependent scores on the Bells Test corrected for age and education.

Conclusion: Based on a large normative sample, the present study provides new normative data on the Bells Test, which could lead to its reliable use in the diagnosis of USN.

Dissociation of cerebrospinal fluid amyloid-β and tau levels in patients with prolonged posttraumatic disorders of consciousness

BACKGROUND

Traumatic brain injury (TBI) is a major risk factor for Alzheimer's disease (AD). Although the mechanisms that lead to AD after a TBI are unclear, we hypothesize that changes in amyloid-β (Aβ) metabolism and abnormal tau phosphorylation are reasonable candidates.

OBJECTIVE

To investigate Aβ and tau dynamics in the chronic phase of TBI.

METHODS

We evaluated Aβ_1-42, total tau (t-tau), and phosphorylated tau (p-tau) levels in the cerebrospinal fluid (CSF) of 15 patients who developed a prolonged disorder of consciousness after a severe TBI (mean time from TBI 271.6 ± 176.5 days).

RESULTS

Reduced Aβ_1-42 levels (median 258 pg/ml, range 90-833.6) were observed in 14/15 patients (93.3%) with severe post-TBI disorders of consciousness. These CSF analysis data did not correlate with time since TBI or with the patients' level of consciousness as determined by the Coma Recovery Scale Revised. Normal t-tau levels (median 95.2 pg/ml, range 52-256.9) were found in all patients. Normal p-tau levels (median 22.2 pg/ml, range 14-72) were observed in 14/15 patients, with just a single patient having a slightly increased p-tau level.

CONCLUSION

The present findings show that Aβ and tau are differently affected in the chronic phase of severe TBI.

Myroides odoratimimus Forms Structurally Complex and Inherently Antibiotic-Resistant Biofilm in a Wound-Like in vitro Model

Myroides odoratimimus is an aerobic, non-fermenting Gram-negative multidrug-resistant bacterium widely distributed in nature that rarely causes infections in immunocompromised patients. We recently described in a diabetic patient a case of recurrent calcaneal ulcer infection caused by a M. odoratimimus strain showing potential for biofilm formation. For the first time, we therefore evaluated the ability of M. odoratimimus to form biofilm under different pH values and glucose concentrations using an in vitro “skin-like” model, and its susceptibility to levofloxacin, meropenem, and tigecycline. The expression of some antibiotic-resistance related genes was also monitored by RT-PCR during planktonic-to-biofilm transition. Our results indicated that M. odoratimimus can produce relevant amounts of biofilm biomass, in a time-dependent manner, especially at acidic pH and regardless of glucose concentration tested. The comparative analysis of MIC and MBC values between planktonic and sessile cells showed that resistance to antibiotics increased during the planktonic-to-biofilm transition. Viable cell count indicated that none of the tested antibiotics were able to completely eradicate preformed biofilms, although meropenem and levofloxacin were the most active causing a significant, dose-independent, reduction of biofilm's viability, as also confirmed by microscopic analysis. RT-PCR showed that antibiotic-resistance related gyrA and acrB genes are over-expressed during the transition from planktonic to sessile (biofilm) lifestyle. Overall, our findings showed that M. odoratimimus can form relevant amounts of inherently antibiotic-resistant biofilm under conditions relevant to wound site, therefore suggesting a role in the pathogenesis of chronic ulcer infections.

Changes in Standard Electroencephalograms Parallel Consciousness Improvements in Patients With Unresponsive Wakefulness Syndrome

OBJECTIVE

To identify changes in the standard electroencephalograms (EEGs) of patients with unresponsive wakefulness syndrome (UWS) who did or did not recover consciousness 6 months after admission to a rehabilitation department.

DESIGN

Prospective cohort study.

SETTING

Unit for severe acquired brain injuries.

PARTICIPANTS

Consecutive patients with UWS (N=28).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

EEG amplitude (reduced or normal), dominant frequency (alpha, theta, or delta), and reactivity (absent or present) were scored at admission and 6 months later. The cumulative Amplitude-Frequency-Reactivity score was evaluated. Clinical assessments were made using the Coma Recovery Scale-Revised.

RESULTS

Sixteen (57.1%) of the 28 patients with UWS recovered consciousness after 6 months, while 12 patients (42.9%) did not recover consciousness. EEG improvements occurred in 14 patients with consciousness recovery (87.5%) and 2 patients without consciousness recovery (16.7%) only. Improvements in EEG dominant frequency (from the theta to the alpha band or from the delta to the theta band), reappearance of EEG reactivity, and Amplitude-Frequency-Reactivity score increase (P<.01) differentiated patients with consciousness improvement from those without consciousness improvement. Six months after admission for rehabilitation, patients with EEG improvements showed higher Coma Recovery Scale-Revised scores than did those without EEG changes (P<.01).

CONCLUSIONS

Most patients who emerge from UWS demonstrate improvement in basic EEG characteristics over time. EEG changes in patients with UWS may aid in the timely recognition of patients transitioning into a minimally conscious state.

Long-Term (Six Years) Clinical Outcome Discrimination of Patients in the Vegetative State Could be Achieved Based on the Operational Architectonics EEG Analysis: A Pilot Feasibility Study

Electroencephalogram (EEG) recordings are increasingly used to evaluate patients with disorders of consciousness (DOC) or assess their prognosis outcome in the short-term perspective. However, there is a lack of information concerning the effectiveness of EEG in classifying long-term (many years) outcome in chronic DOC patients. Here we tested whether EEG operational architectonics parameters (geared towards consciousness phenomenon detection rather than neurophysiological processes) could be useful for distinguishing a very long-term (6 years) clinical outcome of DOC patients whose EEGs were registered within 3 months post-injury. The obtained results suggest that EEG recorded at third month after sustaining brain damage, may contain useful information on the long-term outcome of patients in vegetative state: it could discriminate patients who remain in a persistent vegetative state from patients who reach a minimally conscious state or even recover a full consciousness in a long-term perspective (6 years) post-injury. These findings, if confirmed in further studies, may be pivotal for long-term planning of clinical care, rehabilitative programs, medical-legal decisions concerning the patients, and policy makers.

Longitudinal Assessment of Clinical Signs of Recovery in Patients with Unresponsive Wakefulness Syndrome after Traumatic or Nontraumatic Brain Injury

Although clinical examination is the gold standard for differential diagnosis between unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), clinical signs denoting the first occurrence of conscious behavior in patients with UWS have not been clarified. In this prospective single-center cohort study, 31 consecutive patients with UWS after traumatic brain injury (TBI) (17 patients) or non-TBI were assessed with the Coma Recovery Scale Revised (CRS-R) at admission to a rehabilitation department and after 1, 2, 3, 6, and 12 months. Of the 21 patients who recovered consciousness during the study, 90.5% recovered consciousness within the first 3 months. At the first diagnosis of emergence from UWS, 52.4% of patients showed signs of awareness in only one CRS-R subscale. In particular, 42.9% of patients showed conscious behaviors on the visual CRS-R subscale (23.8% showed visual fixation and 19.1% showed visual pursuit), and 9.5% showed conscious behaviors on the motor CRS-R subscale (half showed localization to a noxious stimulus and half showed object manipulation). Moreover, 23.8% of patients had conscious behaviors on two CRS subscales, always involving the visual and motor CRS-R subscales. The remaining patients showed conscious behaviors on more than two CRS-R subscales. In conclusion, visual fixation and visual pursuit are the commonest early clinical signs denoting MCS. When emerging from UWS, patients with TBI often showed more signs of consciousness and had higher CRS-R scores than patients with non-TBI.

The Chief Role of Frontal Operational Module of the Brain Default Mode Network in the Potential Recovery of Consciousness from the Vegetative State: A Preliminary Comparison of Three Case Reports

It has been argued that complex subjective sense of self is linked to the brain default-mode network (DMN). Recent discovery of heterogeneity between distinct subnets (or operational modules - OMs) of the DMN leads to a reconceptualization of its role for the experiential sense of self. Considering the recent proposition that the frontal DMN OM is responsible for the first-person perspective and the sense of agency, while the posterior DMN OMs are linked to the continuity of 'I' experience (including autobiographical memories) through embodiment and localization within bodily space, we have tested in this study the hypothesis that heterogeneity in the operational synchrony strength within the frontal DMN OM among patients who are in a vegetative state (VS) could inform about a stable self-consciousness recovery later in the course of disease (up to six years post-injury). Using EEG operational synchrony analysis we have demonstrated that among the three OMs of the DMN only the frontal OM showed important heterogeneity in VS patients as a function of later stable clinical outcome. We also found that the frontal DMN OM was characterized by the process of active uncoupling (stronger in persistent VS) of operations performed by the involved neuronal assemblies.

EEG epileptiform abnormalities at admission to a rehabilitation department predict the risk of seizures in disorders of consciousness following a coma

BACKGROUND

Seizures affect about a quarter of patients with disorders of consciousness (DOC) after a coma.

AIMS

We investigated whether the presence of epileptiform abnormalities (EAs) in the electroencephalogram (EEG) of patients with DOC may predict the occurrence of seizures. Moreover, we evaluated whether EAs have a prognostic role in these patients.

METHODS

This was a retrospective single-center cohort study of patients hospitalized between January 2005 and December 2014 in a rehabilitation department (mean time from acute brain injury: 46.1 days). We analyzed 30-minute EEGs at admittance for 112 patients with unresponsive wakefulness syndrome (UWS) or in a minimally conscious state (MCS), then compared occurrence of seizures over the following three months across patients with absent, unilateral, and bilateral EAs (generalized or bilateral independent). Outcomes at three months were assessed in the same groups using the Coma Recovery Scale Revised.

RESULTS

Epileptiform abnormalities were observed in 38 patients (33.9%). Of these, 25 were unilateral, and 13 were bilateral. Seizures occurred in 84.6% of patients with bilateral EAs, which was significantly higher than in patients without EAs (10.8%, p<0.001) or with unilateral EAs (24%, p=0.001). The presence of EAs was not related to etiology or different DOC and did not significantly affect outcomes at three months.

CONCLUSIONS

Patients with EAs at admission to a rehabilitation department have an increased risk of seizures. Specifically, most patients with bilateral EAs had seizures within the following 3 months. Evaluation of EAs in EEGs of patients with DOC may give valuable information in the management of antiepileptic drug treatment.

Autonomic correlates of seeing one's own face in patients with disorders of consciousness

The ability to recognize one's own face is a hallmark of self-awareness. In healthy subjects, the sympathetic skin response evoked by self-face recognition has a greater area under the curve of the signal than responses evoked by other visual stimuli. We evaluated the sympathetic skin responses evoked by self-face images and by six other visual stimuli (conditions) in 15 patients with severe disorders of consciousness and in 15 age-matched healthy subjects. Under all conditions, the evoked area of the sympathetic skin response was smaller in patients with unresponsive wakefulness syndrome, intermediate in patients in a minimally conscious state, and greater in healthy subjects. In patients with unresponsive wakefulness syndrome, no differences were found between the sympathetic skin response area evoked by self-face images and those evoked by other conditions. In patients in a minimally conscious state, the area of the sympathetic skin response evoked by self-face presentation was greater than those evoked by other conditions, even if statistical significance was reached only in the comparison to other stimuli not involving a real face. This finding may be due to the inability of these patients to differentiate their own face from those of others. Taken together, these results probably reflect a varying level of self-awareness between patients with unresponsive wakefulness syndrome and patients in a minimally conscious state, and suggest that the autonomic correlate of self-awareness may have some diagnostic implications for these patients.

EEG predictors of outcome in patients with disorders of consciousness admitted for intensive rehabilitation

OBJECTIVE

This study examined the prognostic value of standard EEG in patients with unresponsive wakefulness syndrome (UWS) or in a minimally conscious state (MCS).

METHODS

EEGs recorded at admission in 106 patients with UWS or in a MCS were analyzed retrospectively. EEG amplitude, dominant frequency, and reactivity to stimuli were correlated to patient outcomes according to the Coma Recovery Scale Revised (CRS-R). In 101 patients, data were integrated to generate a novel Amplitude-Frequency-Reactivity (AFR) scale, with scores ranging from 3 to 7.

RESULTS

Patients with reduced amplitudes showed less improvement in CRS-R scores at 3 months compared to patients with normal amplitudes. Delta, theta, and alpha frequencies were associated with the least, intermediate, and the greatest improvement in CRS-R scores, respectively. Patients with EEG reactivity showed greater improvements in CRS-R scores than patients without reactivity. The AFR scores for these patients were correlated with outcomes.

CONCLUSIONS

Reduced EEG amplitudes and delta frequencies correlated with worse clinical outcomes, while alpha frequencies and reactivity correlated with better outcomes. AFR scores allowed more delineated descriptions of outcomes in patients with normal amplitude, theta frequency, and no reactivity.

SIGNIFICANCE

Standard EEG descriptors are related to the 3-month outcomes in patients with disorders of consciousness.

Long-lasting coma

In this report, we describe the case of a patient who has remained in a comatose state for more than one year after a traumatic and hypoxic brain injury. This state, which we refer to as long-lasting coma (LLC), may be a disorder of consciousness with significantly different features from those of conventional coma, the vegetative state, or brain death. On the basis of clinical, neurophysiological and neuroimaging data, we hypothesize that a multilevel involvement of the ascending reticular activating system is required in LLC. This description may be useful for the identification of other patients suffering from this severe disorder of consciousness, which raises important ethical issues.

Dissociation of vegetative and minimally conscious patients based on brain operational architectonics: factor of etiology

Discrimination between patients in vegetative (VS) and minimally conscious state (MCS) is currently based upon the behavioral gold standard. Behavioral assessment remains equivocal and difficult to interpret as evidence for the presence or absence of consciousness, resulting in possible clinical misdiagnosis in such patients. Application of an operational architectonics (OA) strategy to electroencephalogram (EEG) analysis reveals that absence of consciousness in patients in VS is paralleled by significant impairment in overall EEG operational architecture compared to patients in MCS: neuronal assemblies become smaller, their life span shortened, and they became highly unstable and functionally disconnected (desynchronized). However, in a previous study, patients with different brain damage etiologies were intermixed. Therefore, the goal of the present study was to investigate whether the application of OA methodology to EEG could reliably dissociate patients in VS and MCS independent of brain damage etiology. We conclude that the observed EEG OA structure impairment in patients in VS and partial preservation in patients in MCS is a marker of consciousness/unconsciousness rather than physiological damage. Results of this study may have neuroscientific, clinical, and ethical implications.

A range of antiepileptic drugs do not affect the recovery of consciousness in vegetative and minimally conscious states

Since most antiepileptic drugs (AEDs) have cognitive effects, the aim of this study was to evaluate the influence of AED therapy on the recovery of consciousness in 103 consecutive patients in a vegetative or minimally conscious state (VS, MCS). The levels of cognitive functioning (LCF) score was retrospectively compared after a three-month period of rehabilitation between patients who were medicated (n=54) and patients who were not medicated (n=49) with AEDs. Mean LCF scores in AED-medicated and nonmedicated patients were 2.2±0.7 and 2.3±0.8 at admission and 3.8±2.2 and 3.7±2.1 after three months, respectively (p values>0.05). These results did not change when we compared patients with the same etiology separately, with the same disorder of consciousness only, or patients treated with only one or more than one AED. In conclusion, AEDs did not affect the recovery of consciousness in a large cohort of patients in a VS or MCS following an acute brain injury.

Prognostic Value of Resting-State Electroencephalography Structure in Disentangling Vegetative and Minimally Conscious States

Background. Patients in a vegetative state pose problems in diagnosis, prognosis, and treatment. Currently, no prognostic markers predict the chance of recovery, which has serious consequences, especially in end-of-life decision making. Objective. We aimed to assess an objective measurement of prognosis using advanced electroencephalography (EEG). Methods. EEG data (19 channels) were collected in 14 patients who were diagnosed to be persistently vegetative based on repeated clinical evaluations at 3 months following brain damage. EEG structure parameters (amplitude, duration, and variability within quasi-stationary segments, as well as the spatial synchrony between such segments and the strength of this synchrony) were used to predict recovery of consciousness 3 months later. Results. The number and strength of cortical functional connections between EEG segments were higher in patients who recovered consciousness ( P < .05 to P < .001) compared with those who did not recover. Linear regression analysis confirms that EEG structure parameters are capable of predicting ( P = .0025) recovery of consciousness 6 months postinjury, whereas the same analysis failed to significantly predict patient outcome based on aspects of their clinical history alone ( P = .629) or conventional EEG spectrum power ( P = .473). Conclusions. The result of this preliminary study demonstrates that structural strategy of EEG analysis is better suited for providing prognosis of consciousness recovery than existing methods of clinical assessment and of conventional EEG. Our results may be a starting point for developing reliable prognosticators in patients who are in a vegetative state, with the potential to improve their day-to-day management, quality of life, and access to early interventions.

The value of spontaneous EEG oscillations in distinguishing patients in vegetative and minimally conscious states

OBJECTIVE

The value of spontaneous electroencephalography (EEG) oscillations in distinguishing patients in vegetative state (VS) and minimally conscious states (MCS) was studied.

METHODS

We quantified dynamic repertoire of EEG oscillations in resting condition with closed eyes in patients in VS and MCS. The exact composition of EEG oscillations was assessed by the probability-classification analysis of short-term EEG spectral patterns.

RESULTS

The probability of delta, theta, and slow-alpha oscillations occurrence was smaller for patients in MCS than for VS. Additionally, only patients in MCS demonstrated fast-alpha oscillation occurrence. Depending on the type and composition of EEG oscillations, the probability of their occurrence was either etiology dependent or independent. The probability of EEG oscillations occurrence differentiated brain injuries with different etiologies.

CONCLUSIONS

Spontaneous EEG oscillations have a potential value in distinguishing patients in VS and MCS.

SIGNIFICANCE

This work may have implications for clinical care, rehabilitative programs, and medical-legal decisions in patients with impaired consciousness states following coma due to acute brain injuries.

HIGHLIGHTS

The probability of delta, theta, and slow-alpha oscillations occurrence was smaller and the probability of fast-alpha oscillations occurrence was higher for patients in MCS than for patients in VS. The probability of EEG oscillations occurrence differentiated brain injuries with different etiologies. Spontaneous EEG has a potential value in distinguishing patients in VS and MCS.

Brain-derived neurotrophic factor (Val66Met) polymorphism does not influence recovery from a post-traumatic vegetative state: a blinded retrospective multi-centric study

Brain-derived neurotrophic factor (BDNF) is a neurotrophin that influences neuronal plasticity throughout life. Emergence from a vegetative state (VS) after a traumatic brain injury (TBI) implies that the brain undergoes plastic changes. A common polymorphism in the BDNF gene--BDNF Val66Met (referred to herein as BDNF(Met))--impairs cognitive function in healthy subjects. The aim of this study was to determine whether the BDNF(Met) polymorphism plays a role in the recovery of consciousness and cognitive functions in patients in a VS after a TBI. Fifty-three patients in a VS 1 month after a TBI were included in the study and genotyped for the BDNF(Met) polymorphism. Scores of levels of cognitive functioning (LCF) at 1, 3, 6, and 12 months post-TBI were retrospectively compared in patients without (Val group), and with (Met group), the BDNF(Met) polymorphism. The BDNF(Met) polymorphism was detected in 20 out of the 53 patients. The mean LCF scores in the Val and Met groups were 1.6±0.5 and 1.4±0.5 at 1 month, 2.3±0.7 and 2.5±1.2 at 3 months, 3.3±1.7 and 3.5±1.7 at 6 months, and 4±1.9 and 3.9±1.8 at 12 months, respectively (p>0.05). The percentages of patients in the Val and Met groups who emerged from the VS were 36.4% and 30% at 3 months, 66.3% and 70% at 6 months, and 70% and 87.5% at 12 months (p>0.05), respectively. These findings provide evidence that the BDNF(Met) polymorphism is not involved in cognitive improvement in patients with a VS following TBI. Future studies should focus on the role of other BDNF polymorphisms in the recovery from a VS.

Design and evaluation of NEUROBike: a neurorehabilitative platform for bedridden post-stroke patients

Over the past decades, a large number of robotic platforms have been developed which provide rehabilitative treatments aimed at recovering walking abilities in post-stroke patients. Unfortunately, they do not significantly influence patients' performance after three months from the accident. One of the main reasons underlying this result seems to be related to the time of intervention. Specifically, although experimental evidences suggest that early (i.e., first days after the injury) and intense neuro-rehabilitative treatments can significantly favor the functional recovery of post-stroke patients, robots require patients to be verticalized. Consequently, this does not allow them to be treated immediately after the trauma. This paper introduces a new robotic platform, named NEUROBike, designed to provide neuro-rehabilitative treatments to bedridden patients. It was designed to provide an early and well-addressed rehabilitation therapy, in terms of kinesiology, efforts, and fatigue, accounting for exercises functionally related to daily motor tasks. For this purpose, kinematic models of leg-joint angular excursions during both walking and sit-to-stand were developed and implemented in control algorithms leading both passive and active exercises. Finally, a set of pilot tests was carried out to evaluate the performance of the robotic platform on healthy subjects.

DMN Operational Synchrony Relates to Self-Consciousness: Evidence from Patients in Vegetative and Minimally Conscious States

The default mode network (DMN) has been consistently activated across a wide variety of self-related tasks, leading to a proposal of the DMN’s role in self-related processing. Indeed, there is limited fMRI evidence that the functional connectivity within the DMN may underlie a phenomenon referred to as self-awareness. At the same time, none of the known studies have explicitly investigated neuronal functional interactions among brain areas that comprise the DMN as a function of self-consciousness loss. To fill this gap, EEG operational synchrony analysis [1, 2] was performed in patients with severe brain injuries in vegetative and minimally conscious states to study the strength of DMN operational synchrony as a function of self-consciousness expression. We demonstrated that the strength of DMN EEG operational synchrony was smallest or even absent in patients in vegetative state, intermediate in patients in minimally conscious state and highest in healthy fully self-conscious subjects. At the same time the process of ecoupling of operations performed by neuronal assemblies that comprise the DMN was highest in patients in vegetative state, intermediate in patients in minimally conscious state and minimal in healthy fully self-conscious subjects. The DMN’s frontal EEG operational module had the strongest decrease in operational synchrony strength as a function of selfconsciousness loss, when compared with the DMN’s posterior modules. Based on these results it is suggested that the strength of DMN functional connectivity could mediate the strength of self-consciousness expression. The observed alterations similarly occurred across EEG alpha, beta1 and beta2 frequency oscillations. Presented results suggest that the EEG operational synchrony within DMN may provide an objective and accurate measure for the assessment of signs of self-(un)consciousness in these challenging patient populations. This method therefore, may complement the current diagnostic procedures for patients with severe brain injuries and, hence, the planning of a rational rehabilitation intervention.

Life or death: prognostic value of a resting EEG with regards to survival in patients in vegetative and minimally conscious States

OBJECTIVE

To investigate the potentially prognostic value of a resting state electroencephalogram (EEG) with regards to the clinical outcome from vegetative and minimally conscious states (VS and MCS) in terms of survival six months after a brain injury.

METHODS

We quantified a dynamic repertoire of EEG oscillations in resting condition with eyes closed in patients in VS and MCS. The exact composition of EEG oscillations was assessed by analysing the probability-classification of short-term EEG spectral patterns.

RESULTS

Results demonstrated that (a) the diversity and the variability of EEG for Non-Survivors were significantly lower than for Survivors; and (b) a higher probability of mostly delta and slow-theta oscillations occurring either alone or in combination were found during the first assessment for patients with a bad outcome (i.e., those who died) within six months of an injury compared to patients who survived. At the same time, patients with a good outcome (i.e., those who survived) after six months post-injury had a higher probability of mostly fast-theta and alpha oscillations occurring either alone or in combination during the first assessment when compared to patients who died within six months of an injury.

CONCLUSIONS

Resting state EEGs properly analysed may have a potentially prognostic value with regards to the outcome from VS or MCS in terms of survival six months after a brain injury.

SIGNIFICANCE

This work may have implications for clinical care, rehabilitative programmes and medical-legal decisions for patients with impaired consciousness states after being in a coma due to acute brain injuries.

Efficacy of intra-articular injection of botulinum toxin type A in refractory hemiplegic shoulder pain

OBJECTIVE

To evaluate the efficacy of intra-articular injection of botulinum toxin type A (BTX-A) in relieving hemiplegic shoulder pain (HSP).

DESIGN

Pilot study with assessments before and after BTX-A intra-articular injection.

SETTING

Hospital rehabilitation department.

PARTICIPANTS

Patients (N=5) with HSP refractory to standard treatments and pain score at rest greater than 7 on a pain visual analog scale (VAS) of 0 to 10cm.

INTERVENTION

Intra-articular BTX-A injection.

MAIN OUTCOME MEASURE

Variation in VAS score at rest and during 90° passive arm abduction 2 and 8 weeks after BTX-A intra-articular injection.

RESULTS

Baseline VAS score was 8.7±1 at rest and 9.8±0.4 during passive arm abduction. It clearly decreased at 2 (1.5±1.1 at rest, P=.001; 3±1.2 during arm abduction, P<.001) and 8 weeks (1.5±1.2 at rest, P=.001; 2.3±1.1 during arm abduction, P<.001) after BTX-A intra-articular injection.

CONCLUSIONS

We found a strong correlation between intra-articular BTX-A injection and pain relief in patients with HSP. This result could provide the rationale for blind randomized controlled trials designed to better evaluate the safety and efficacy of intra-articular BTX-A injection in patients with refractory HSP.

Evaluation of leg joint trajectories while carrying out passive manipulation by NEUROBike

During the last decades, many robotic platforms aimed at post-stroke neurorehabilitation of locomotion have been developed. These devices have been designed to enhance the possibilities of conventional rehabilitation providing safe, highly accurate, intensive and prolonged treatments. Nevertheless, up to now, robotic aided therapy has not yet promoted improvements of the motor performance significantly greater than those achieved by the conventional therapy. According to previous studies, we believe that this result may be partially ascribed to two main issues: the rehabilitation mediated by robots is usually provided too late from the trauma and it mainly consists of passive and cyclic manipulation of the legs. Our proposal to overcome some of the supposed limits is NEUROBike, an operative mechatronic platform able to lead leg manipulation as soon as possible after the trauma, that is when patients still lie on their own beds. Moreover, NEUROBike has been designed to provide both passive and cyclic manipulation of leg joints with trajectories similar to those related to natural walking, and motor task involving random efforts. This work presents the comparison between desired and measured leg joint trajectories while NEUROBike provides cyclic and passive leg manipulation. The results show that angular excursions at proximal joints were reasonably comparable with those obtained by the velocity based model even though they were affected by a positive offset involving emphasized flexion of hip and knee during the gait cycle.

Characterisation of the sympathetic skin response evoked by own-face recognition in healthy subjects

The ability to recognise one's own face is crucial for self-identity formation and it plays a key role in the development of social interactions. Our starting hypothesis was that own-face recognition may be a psychophysiological phenomenon capable of activating the vegetative system in a peculiar manner, via sympathetic pathways. To test this hypothesis we studied the sympathetic skin responses (SSRs) evoked in 18 healthy subjects by the image of their own faces and by six other different visual stimuli. The SSRs were enhanced when participants were shown their own faces. Both SSR area and SSR amplitude contributed to this phenomenon. This work may offer new insights into the psycho- physiological processes involved in own-face recognition; moreover, the SSR could be a useful tool for future studies of patients affected by neuropsychiatric disorders presenting impairment of own-face recognition or representation of self-identity.

A protocol for the assessment of 3D movements of the head in persons with cervical dystonia

OBJECTIVE

To design and test a protocol for the assessment of neck movements in patients affected by cervical dystonia by using an electromagnetic system. This approach could overcome the limits of the current assessment scales in this specific field.

BACKGROUND

Initial assessment and function recovery during treatments are diagnosed by the clinician using outcome scales which present many drawbacks in terms of easiness of use, sensitivity, and reliability.

DESIGN

A three-dimensional motion analysis system was used to record six different head movements.

METHODS

Six able-bodied subjects and 10 subjects affected by cervical dystonia participated in this study. For the different head movements three kinematic parameters (a symmetry index and two indexes related to the reduction of the range of motion) have been extracted in order to compare the performance of able-bodied and disabled persons.

RESULTS

The features selected allowed highlighting of the differences between able-bodied and disabled subjects for the degrees of freedom of the neck.

CONCLUSIONS

Using a motion analysis system, three kinematic features were extracted from head movements. They seem to allow a more objective assessment of the disability and a more appropriated strategy for the management of patients affected by cervical dystonia.

Automated assessment of cervical dystonia

We developed an automated and objective method to measure posture and voluntary movements in patients with cervical dystonia using Fastrack, an electromagnetic system consisting of a stationary transmitter station and four sensors. The junction lines between the sensors attached to the head produced geometrical figures on which the corresponding aspects of the head were superimposed. The head position in the space was reconstructed and observed from axial, sagittal, and coronal planes. Four patients with cervical dystonia and 6 healthy subjects were studied. Each patient was representative of one of the typical patterns of cervical dystonia. The study allowed the authors to collect quantitative data on posture and range of motion of the head. This pilot study demonstrates the efficacy of the Fastrack system to objectively measure the head position in cervical dystonia patients.

Role of the dopamine D5 receptor (DRD5) as a susceptibility gene for cervical dystonia

Cervical dystonia (CD) is one of the most common forms of primary dystonia. The pathogenesis of the disease is still unknown, although evidence suggests a role for genetic factors. Recently, a polymorphism in the dopamine D5 receptor (DRD5) gene has been associated with the disease in a British population, suggesting that DRD5 is a susceptibility gene for CD. To confirm these data, we performed a case-control study of the microsatellite (CT/GT/GA)(n) at the DRD5 locus in 104 Italian CD patients and 104 healthy controls. The frequency of allele 4 was higher in the CD patients compared to the controls. This resulted in a twofold increased risk of developing the disease. These results provide further evidence of an association between DRD5 and cervical dystonia, supporting the involvement of the dopamine pathway in the pathogenesis of CD.

Obsessive compulsive disorder among idiopathic focal dystonia patients: an epidemiological and family study

BACKGROUND

A disturbed function of striato-thalamo-cortical circuitry is hypothesized to underlie idiopathic focal dystonia (IFD) and obsessive compulsive disorder (OCD), two severe and disabling neurologic and psychiatric disorders. Previous studies on small samples showed either higher obsessionality scores or higher frequency of OCD in dystonic patients than in normal control subjects. The aim of this study was to evaluate the frequency and familial loading of OCD in a population of patients with IFD.

METHODS

We evaluated OCD diagnosis and family history in 76 patients affected by IFD.

RESULTS

Of our subjects 19.7% satisfied DSM-IV criteria for OCD diagnosis and had a family morbidity risk for OCD of 13.8%, significantly higher than that found in the general population.

CONCLUSIONS

Our results support the hypothesis of a common pathologic background for OCD and IFD, at least in a subgroup of IFD, indicating basal ganglia dysfunction.

Sporadic failure of botulinum toxin treatment in usually responsive patients with adductor spasmodic dysphonia

Botulinum toxin (BT) injections into vocalis (thyroarytenoid) muscle is currently considered the first-choice treatment for adductor spasmodic dysphonia, producing improvement for an average period of 3 months. In our experience, sporadic failure of BT efficacy can occur even in patients usually responsive to this therapy. The reasons for these episodes have not been clarified. In a retrospective, open trial, we investigated the effect toxin preparation (Botox or Dysport) and injection monitoring (electromyography or laryngoscopy) on the success rate of BT treatment. We studied 15 patients with adductor dysphonia usually responsive to BT therapy. BT was administered into the vocalis muscle in 112 and 36 injections under electromyographic or laryngoscopic guidance, respectively. Botox and Dysport were used in 106 and 42 sessions, respectively. In 29% of all injections, no subjective or objective changes, nor side effects were observed. Failure rate did not differ using electromyographic (28.6%) or laryngoscopic (30.5%) guidance. Failure rates with Botox and Dysport were 30.2% and 26.2%, respectively, but this difference was not statistically significant. These data suggest that treatment failure may occur regardless of the method of injection and of the drug preparation used, possibly due to mislocalisation of vocal folds.