An open-label trial of bromocriptine in nonfluent aphasia: a qualitative analysis of word storage and retrieval

Better language through chemistry: Augmenting speech-language therapy with pharmacotherapy in the treatment of aphasia

Speech and language therapy is the standard treatment of aphasia. However, many individuals have barriers in seeking this measure of extensive rehabilitation treatment. Investigating ways to augment therapy is key to improving poststroke language outcomes for all patients with aphasia, and pharmacotherapies provide one such potential solution. Although no medications are currently approved for the treatment of aphasia by the United States Food and Drug Administration, numerous candidate mechanisms for pharmaceutical manipulation continue to be identified based on our evolving understanding of the neurometabolic experience of stroke recovery across molecular, cellular, and functional levels of inquiry. This chapter will review evidence for catecholaminergic, glutamatergic, cholinergic, and serotonergic drug therapies and discuss future directions for both candidate drug selection and pharmacotherapy practice in people with aphasia.

Diagnosing and managing post-stroke aphasia

Introduction: Aphasia is a debilitating language disorder and even mild forms of aphasia can negatively affect functional outcomes, mood, quality of life, social participation, and the ability to return to work. Language deficits after post-stroke aphasia are heterogeneous. Areas covered: The first part of this manuscript reviews the traditional syndrome-based classification approach as well as recent advances in aphasia classification that incorporate automatic speech recognition for aphasia classification. The second part of this manuscript reviews the behavioral approaches to aphasia treatment and recent advances such as noninvasive brain stimulation techniques and pharmacotherapy options to augment the effectiveness of behavioral therapy. Expert opinion: Aphasia diagnosis has largely evolved beyond the traditional approach of classifying patients into specific syndromes and instead focuses on individualized patient profiles. In the future, there is a great need for more large scale randomized, double-blind, placebo-controlled clinical trials of behavioral treatments, noninvasive brain stimulation, and medications to boost aphasia recovery.

Adjunctive Approaches to Aphasia Rehabilitation: A Review on Efficacy and Safety

Aphasia is one of the most socially disabling post-stroke deficits. Although traditional therapies have been shown to induce adequate clinical improvement, aphasic symptoms often persist. Therefore, unconventional rehabilitation techniques which act as a substitute or as an adjunct to traditional approaches are urgently needed. The present review provides an overview of the efficacy and safety of the principal approaches which have been proposed over the last twenty years. First, we examined the effectiveness of the pharmacological approach, principally used as an adjunct to language therapy, reporting the mechanism of action of each single drug for the recovery of aphasia. Results are conflicting but promising. Secondly, we discussed the application of Virtual Reality (VR) which has been proven to be useful since it potentiates the ecological validity of the language therapy by using virtual contexts which simulate real-life everyday contexts. Finally, we focused on the use of Transcranial Direct Current Stimulation (tDCS), both discussing its applications at the cortical level and highlighting a new perspective, which considers the possibility to extend the use of tDCS over the motor regions. Although the review reveals an extraordinary variability among the different studies, substantial agreement has been reached on some general principles, such as the necessity to consider tDCS only as an adjunct to traditional language therapy.

Efficacy of Levetiracetam in Treatment of Childhood Stuttering

Background:

Stuttering is a kind of speech disorder that affects about 1% of total population. As the origin of this disorder is not obviously diagnosed yet, various remedies have been practiced and among them different medicines have been studied, but unfortunately no significant effective drugs have been recognized yet. As stuttering imposes a great social and mental costs to the patients and their families, finding an effective medicine will help significantly. In this study we have focused on the effects of levetiracetam (LEV) treatment on children suffering from stuttering.

Methods:

In this clinical trial study, 30 children aged > 3 years (median 3.8 years) with stuttering and abnormal sleep electroencephalogram (EEG) were treated by LEV and followed-up for a minimum period of 6 weeks. The starting dose of 20 mg/kg/day was increased at an interval of 1 week by 20 mg/kg/day, if necessary, up to maximum dose of 60 mg/kg/day.

Results:

Overall LEV was effective in 70% of patients, decreasing stuttering to at least 50%. Three children (10%) became stuttering-free and only in one (3.3%) child an increase in stuttering was observed. There were statistically significant differences for efficacy in the presence of variables such as age groups, seizure, stuttering family history, and EEG data.

Conclusions:

LEV is an effective drug for treatment of childhood stuttering in those that have abnormal sleep EEG.

An update on medications and noninvasive brain stimulation to augment language rehabilitation in post-stroke aphasia

INTRODUCTION

Aphasia is among the most debilitating outcomes of stroke. Aphasia is a language disorder occurring in 10-30% of stroke survivors. Speech and Language Therapy (SLT) is the gold standard, mainstay treatment for aphasia, but gains from SLT may be incomplete. Pharmaceutical and noninvasive brain stimulation (NIBS) techniques may augment the effectiveness of SLT. Areas covered: Herein reviewed are studies of the safety and efficacy of these adjunctive interventions for aphasia, including randomized placebo-controlled and open-label trials, as well as case series from Pubmed, using search terms 'pharmacological,' 'tDCS' or 'TMS' combined with 'aphasia' and 'stroke.' Expert commentary: Relatively small studies have included participants with a range of aphasia types and severities, using inconsistent interventions and outcome measures. Results to-date have provided promising, but weak to moderate evidence that medications and/or NIBS can augment the effects of SLT for improving language outcomes. We end with recommendations for future approaches to studying these interventions, with multicenter, double-blind, randomized controlled trials.

Amphetamine and other pharmacological agents in human and animal studies of recovery from stroke

Neuromodulation with pharmacological agents, including drugs of abuse such as amphetamine, when paired with behavioral experience, has been shown to positively modify outcomes in animal models of stroke. A number of clinical studies have tested the efficacy of a variety of drugs to enhance recovery of language deficit post-stroke. The purpose of this paper is to: (1) present pertinent animal studies supporting the use of dextro-amphetamine sulfate (AMPH) to enhance recovery after experimental lesions with emphasis on the importance of learning dependent activity for lasting recovery; (2) briefly review neuropharmacological explorations in the treatment of aphasia; (3) present a pilot study in aphasia exploring a drug combination of AMPH and donepezil hydrochloride paired with behavioral treatment to facilitate recovery; and (4) conclude with comments regarding the role of adjunctive pharmacotherapy in the rehabilitation of aphasia, particularly AMPH.

Drug treatment of poststroke aphasia

Impairment of language function (aphasia) is one of the most common neurological symptoms after stroke. Approximately one in every three patients who have an acute stroke will suffer from aphasia. The estimated incidence and prevalence of stroke in Western Europe is 140 and 800 per 100,000 of the population. Aphasia often results in significant disability and handicap. It is a major obstacle for patients to live independently in the community. When recovery from aphasia occurs, it is usually incomplete and patients are rarely able to return to full employment and other social activities. Currently, the main treatment for aphasia is conventional speech and language therapy. However, the effectiveness of this intervention has not been conclusively demonstrated and empirical observations suggest that spontaneous biological recovery may explain most of the improvement in language function that occurs in aphasics. The generally poor prognosis of the severe forms of poststroke language impairment (Broca, Wernicke and global aphasia), coupled with the limited effectiveness of conventional speech and language therapy has stimulated the search for other treatments that may be used in conjunction with speech and language therapy, including the use of various drugs. Dopamine agonists, piracetam (Nootropil), amphetamines, and more recently donepezil (Aricept), have been used in the treatment of aphasia in both the acute and chronic phase. The justification for the use of drugs in the treatment of aphasia is based on two types of evidence. Some drugs, such as dextroamphetamine (Dexedrine), improve attention span and enhance learning and memory. Learning is an essential mechanism for the acquisition of new motor and cognitive skills, and hence, for recovery from aphasia. Second, laboratory and clinical data suggest that drug treatment may partially restore the metabolic function in the ischemic zone that surrounds the brain lesion and also has a neuroprotective effect following acute brain damage. An example of this is the nootropic agent piracetam. Extensive animal studies have demonstrated the beneficial effects of this and other drugs on neural plasticity, but data on humans are still sparse. This review provides a critical analysis of the current evidence of the effectiveness of these drugs in the treatment of acute and chronic aphasia.

Psycholinguistics of Aphasia Pharmacotherapy: Asking the Right Questions

BACKGROUND

Among the obstacles to demonstrating efficacy of pharmacological intervention for aphasia is quantifying patients' responses to treatment in a statistically valid and reliable manner. In many of the review papers on this topic (e.g., Berthier et al., 2011; de Boissezon, Peran, de Boysson, & Démonet, 2007; Small & Llano, 2009), detailed discussions of various methodological problems are highlighted, with some suggestions on how these shortcomings should be addressed. Given this deep understanding of caveats associated with the experimental design of aphasia pharmacotherapy studies (e.g., Berthier et al., 2011), investigations continue to produce inconsistent results.

AIM

In this review paper we suggest that inclusion of theory-driven linguistic measures in aphasia pharmacotherapy studies would add an important step toward elucidating precise patterns of improvement in language performance resulting from pharmacotherapeutic intervention.

MAIN CONTRIBUTION

We provide a brief review of the clinical approaches currently used in pharmacotherapy studies of aphasia, which often lack psycholinguistic grounding. We then present ways in which psycholinguistic models can complement this approach, offering a rationale for task selection, and as a result, lead to a better understanding of treatment effects. We then follow with an example of how such an integrative approach can be implemented in studies targeting stress reduction in people with aphasia, via beta-blocking agents, as a means to augment language performance, using the psycholinguistic framework of "linguistic anxiety" outlined in Cahana-Amitay et al, 2011 as our guideline.

CONCLUSION

We conclude that the incorporation of psycholinguistic models into aphasia pharmacotherapy studies can increase the resolution with which we can identify functional changes.

Escitalopram-induced word finding difficulty

Escitalopram is the most selective serotonin reuptake inhibitor used for treatment of major depressive disorder and generalized anxiety disorder. No available report indicating escitalopram may induce word finding difficulty. Here we are presenting a 50-year-old patient who suffered from escitalopram-induced word finding difficulty and the symptom resolved after replacing with bupropion. Carefully monitoring word finding difficulty and speech fluency during antidepressant treatment is important in clinical practice when using selective serotonin reuptake inhibitors, especially escitalopram.

Dopaminergic therapy in aphasia

BACKGROUND

The dopaminergic system is involved in a wide range of cognitive functions including motor control, reward, memory, attention, problem-solving and learning. This has stimulated interest in investigating the potential of dopaminergic drugs as cognitive enhancers in aphasic patients.

AIM

To discuss the evidence for the use of dopaminergic agents in patients with aphasia. Levodopa (L-dopa) and the dopamine agonist bromocriptine are the two drugs that have been trialled to date. We discuss, in some detail, the 15 studies that have been published on this topic from the first case report in 1988 to the present (2012), and assess the evidence from each.

MAIN CONTRIBUTION

In addition to summarising the effectiveness of the drugs that have been tried, we examine the possible cognitive mechanisms by which dopaminergic drugs may act on language function and aphasia recovery. Given the wide range of dopaminergic drugs, it is surprising that such a narrow range has been trialled in aphasic patients. Important lessons are to be learned from published studies and we discuss optimal trial designs to help guide future work.

CONCLUSIONS

The evidence for the efficacy of dopaminergic agents in aphasia therapy is mixed. Further trials with better tolerated agents are required. Optimal trial designs with appropriate control groups or blocks should be used. The mechanism of action is unclear, but at the cognitive level the evidence points towards either (re)learning of word-forms or their improved retrieval.

Crossover trial of subacute computerized aphasia therapy for anomia with the addition of either levodopa or placebo

BACKGROUND

The effect of levodopa on recovery from aphasia is controversial.

OBJECTIVE

To determine whether levodopa enhances the effect of intensive computer-assisted therapy (CAT) of anomia in the postacute stage of aphasia.

METHODS

Double-blind multiple case study with intrasubject crossover design comparing the effect of levodopa (100 mg) versus placebo, each given for 2 weeks.

SUBJECTS

Twelve patients with onset of aphasia from 2 to 9 weeks after stroke or traumatic brain injury were compared on naming performance on items trained and not trained with CAT. Subjects were randomized to either levodopa or placebo first, separated by a 1-week washout, and then switched to the other drug intervention for the second 2-week CAT intervention. The subjects also received routine aphasia therapies during these periods.

RESULTS

All patients improved their naming performance for items trained by CAT in both periods (P = .001). No significant difference was found between the placebo and levodopa phases.

CONCLUSION

Administration of levodopa for 2 weeks during the postacute stage of aphasia did not augment the positive effects of subacute intensive language treatment with CAT for a spoken naming task.

New approach to the rehabilitation of post-stroke focal cognitive syndrome: effect of levodopa combined with speech and language therapy on functional recovery from aphasia

OBJECTIVE

Few studies confirm that pharmacological treatments support post-stroke recovery. The purpose of this study was to determine whether the combination of levodopa with language therapy improves aphasia rehabilitation.

METHODS

We did a prospective, randomized, placebo-controlled, double-blind study in which twenty patients received levodopa before each language therapy session, and an additional 19 received a placebo. Language training was provided during a 3-week period. The efficacy variables were changes from baseline in Boston Diagnostic Aphasia Examination (BDAE) scores.

RESULTS

Patients receiving levodopa experienced greater language improvement in verbal fluency and repetition, compared to patients receiving placebo. Improvement was particularly distinct in patients with anterior lesions.

CONCLUSIONS

Supplementing language therapy with levodopa may improve recovery from aphasia in patients with frontal lesions.

Amantadine for adynamic speech: possible benefit for aphasia?

OBJECTIVE

Dopaminergic agents may stimulate behavior and verbal expression after frontal lobe dysfunction. Although amantadine is used in neurorehabilitation of motivational disorders and head injury, it is not commonly prescribed to improve aphasia. This pilot study examined verbal fluency on and off amantadine for nonfluent speech.

DESIGN

Four participants undergoing inpatient rehabilitation, meeting criteria for transcortical motor aphasia had stroke (2), stroke postaneurysm surgery (1), or brain tumor resection (1). We administered 100 mg of amantadine twice a day in an open-label, on-off protocol, with multiple assessments per on-off period.

RESULTS

Off medication, subjects generated a mean 12.62 of words (abnormally few) on the Controlled Oral Word Association test. On medication, word generation significantly improved to 17.71 words (P = 0.04), although scores remained psychometrically in the abnormal range.

CONCLUSIONS

Further research on amantadine, specifically for nonfluent speech and nonfluent aphasia, including effects on functional communication and control conditions, may be warranted.

Aphasia: Associated Disturbances in Affect, Behavior, and Cognition in the Setting of Speech and Language Difficulties

Patients with disturbances in affect, behavior, and cognition present a variety of challenges to healthcare providers; their evaluation and treatment becomes especially problematic in the setting of speech and language difficulties. The authors present the case of a man who sustained a left-side cerebrovascular accident with aphasia and discuss the approach to his diagnosis and treatment. Moreover, since a variety of speech and language problems can arise after stroke and since patients and their treaters can become frustrated by impaired communication and diagnostic uncertainties, authors review the clinical manifestations, timing, and treatment of such conditions so that treatment can be improved.

Disorders of speech and language: aphasia, apraxia and dysarthria

PURPOSE OF REVIEW

We review recent important papers pertaining to acquired aphasia, apraxia of speech and dysarthria with special attention to clinically significant work published in the last 12 months.

RECENT FINDINGS

The role of the contralateral inferior frontal gyrus in language recovery after stroke is controversial, but is an area of active research, particularly in functional imaging studies. Recent treatment studies in poststroke aphasia have shown that intensity of language therapy may be more important than the method of therapy. Some studies have indicated that amphetamines, piracetam and repetitive transcortical magnetic stimulation may be effective adjuncts to speech and language therapy. Treatment studies for poststroke dysarthria indicate that speech supplementation strategies may be effective and deserve further study.

SUMMARY

Recent studies of aphasia provide clues regarding language recovery poststroke, but further studies of the role of the ipsi and contralateral inferior frontal gyrus are necessary, and should be longitudinal. There are relatively few recent studies on the treatment of acquired disorders of speech and language, other than poststroke aphasia.

Disfluent speech in patients with partial epilepsy: beneficial effect of levetiracetam

PURPOSE

The aim of this study was to evaluate the clinical effects of levetiracetam (LEV) in patients with partial epilepsy and disfluent speech.

METHODS

Five consecutive patients with partial epilepsy and disfluent speech resulting from developmental or neurogenic stuttering were enrolled in a 9-week, open-label, prospective study. LEV was given in combination with carbamazepine (CBZ) or phenytoin (PHT) at dosages ranging from 500 to 1500mg twice daily. The severity of stuttering was assessed with the verbal fluency test (VFT), and with the patient global impression of improvement (PGI), at baseline and after 9weeks. Electroencephalography and serum monitoring of CBZ and PHT levels were done before and after the study. Seizure frequency was monitored.

RESULTS

After LEV therapy, verbal fluency for all patients, as measured by the VFT, improved from 25% at baseline to 64%, as did the speed of oral reading, from 5 to 23%. On the PGI, all patients rated themselves as better and as having less disfluent speech after LEV therapy. For four patients with incomplete control of their seizures, the seizure count decreased by more than 50% after LEV therapy. The beneficial effect of LEV on verbal disfluency demonstrated on the PGI persisted for the entire period of observation, which ranged from 7 to 11 months.

CONCLUSIONS

As an add-on therapy, LEV seems to improve verbal fluency in patients with partial epilepsy and disfluent speech. This effect seems unrelated to the antiepileptic activity of the drug. A placebo-controlled trial of LEV in patients with this kind of verbal disfluency is warranted.

Tonic dopaminergic stimulation impairs associative learning in healthy subjects

Endogenous dopamine plays a central role in salience coding during associative learning. Administration of the dopamine precursor levodopa enhances learning in healthy subjects and stroke patients. Because levodopa increases both phasic and tonic dopaminergic neurotransmission, the critical mechanism mediating the enhancement of learning is unresolved. We here probed how selective tonic dopaminergic stimulation affects associative learning. Forty healthy subjects were trained in a novel vocabulary of 45 concrete nouns over the course of 5 consecutive training days in a prospective, randomized, double-blind, placebo-controlled design. Subjects received the tonically stimulating dopamine-receptor agonist pergolide (0.1 mg) vs placebo 120 min before training on each training day. The dopamine agonist significantly impaired novel word learning compared to placebo. This learning decrement persisted up to the last follow-up 4 weeks post-training. Subjects treated with pergolide also showed restricted emotional responses compared to the PLACEBO group. The extent of 'flattened' affect with pergolide was related to the degree of learning inhibition. These findings suggest that tonic occupation of dopamine receptors impairs learning by competition with phasic dopamine signals. Thus, phasic signaling seems to be the critical mechanism by which dopamine enhances associative learning in healthy subjects and stroke patients.

Metacognition in stroke: bedside assessment and relation to location, size, and stroke severity

BACKGROUND

Frontal syndromes are poorly represented on stroke scales, yet may constitute an important component of the neurologic deficit impacting treatment and rehabilitation efforts.

AIMS

To validate an assessment of a frontal network syndrome score (FNSS) in stroke and to ascertain the relationship of the FNSS to lesion location, volume, and severity in young people with stroke.

METHODS

Accrual through a cognitive stroke registry of young, alert, nonaphasic, nonencephalopathic, nonsubstance abuse prone people who were tested with the 16 domain FNSS within 4 weeks of their stroke. Lesion location was determined by the Cerefy 3-dimensional, digital, coxial brain atlas identifying 6 regions of cerebral interest. Lesion severity was assessed by the National Institute of Health Stroke Score and infarct volume was measured in cubic centimeters.

RESULTS

From a sample of 456 cases in the registry after exclusions of encephalopathy, depression, and aphasia, cases with frontal network syndrome encompassed 132 of 341 persons (39%). Of these patients (n=80) with mean age 45.7 years [confidence interval (CI): 43.4, 48.1], educational level 13.1 years (CI:12.5, 13.6), mean National Institute of Health Stroke Score of 3.3 (CI: 2.6, 4.0), and mean lesion volume 30.3 mL (CI: 13.7, 46.9), had full testing with the FNSS battery yielding sensitivity (93%), specificity (74%), positive predictive value (79%), negative predictive value (90%), and a good interrater reliability (kappa=0.89, P=0.001). Construct validity testing with 15 frontal neuropsychologic tests revealed good to excellent significant Pearson r values in 14 of 15 of the tests. There was no correlation (Pearson's) for lesion volume (r=0.07, P=0.52) but significant correlation with stroke severity (r=0.23, P=0.03). Analysis of variance testing of the FNSS revealed significant differences for all 6 domains without intergroup significant differences for frontal network syndrome domains in the stroke group.

CONCLUSIONS

The FNSS is a valid, practical measure of frontal syndromes in stroke. Frontal syndromes are common in young people with stroke and may be present no matter where the lesion, are not dependent on size of stroke and have a low correlation with stroke severity.

Pharmakologische Zusatzbehandlung in der Aphasietherapie

Aphasia is one of the most frequent and disabling consequences of stroke. Poor spontaneous recovery and the limited success of conventional speech therapy bring up the question of how current treatment approaches can be improved. Besides increasing training frequency-with daily sessions lasting several hours and high repetition rates of language materials ("massed training")-adjuvant drug therapy may help to increase therapy efficacy. In this article, we illuminate the potential of monoaminergic (bromocriptine, levodopa, d-amphetamine) and cholinergic (donepezil) substances for treating aphasia. For a final evaluation of combined massed training and adjuvant pharmacotherapy, randomized, placebo-controlled (multicenter) clinical trials with sufficient numbers of patients are needed. Furthermore, results of experimental animal studies of functional recovery in brain damage raise hopes that neurotrophic factors or stem cells might find a place in recovery from aphasia in the intermediate future.

Poststroke Aphasia

Aphasia, the loss or impairment of language caused by brain damage, is one of the most devastating cognitive impairments of stroke. Aphasia is present in 21-38% of acute stroke patients and is associated with high short- and long-term morbidity, mortality and expenditure. Recovery from aphasia is possible even in severe cases. While speech-language therapy remains the mainstay treatment of aphasia, the effectiveness of conventional therapies has not been conclusively proved. This has motivated attempts to integrate knowledge from several domains in an effort to plan more rational therapies and to introduce other therapeutic strategies, including the use of intensive language therapy and pharmacological agents. Several placebo-controlled trials suggest that piracetam is effective in recovery from aphasia when started soon after the stroke, but its efficacy vanishes in patients with chronic aphasia. Drugs acting on catecholamine systems (bromocriptine, dexamfetamine) have shown varying degrees of efficacy in case series, open-label studies and placebo-controlled trials. Bromocriptine is useful in acute and chronic aphasias, but its beneficial action appears restricted to nonfluent aphasias with reduced initiation of spontaneous verbal messages. Dexamfetamine improves language function in subacute aphasia and the beneficial effect is maintained in the long term, but its use is restricted to highly selected samples. Pharmacological agents operating on the cholinergic system (e.g. donepezil) have shown promise. Data from single-case studies, case series and an open-label study suggest that donepezil may have beneficial effects on chronic poststroke aphasia. Preliminary evidence suggests that donepezil is well tolerated and its efficacy is maintained in the long term. Randomised controlled trials of donepezil and other cholinergic agents in poststroke aphasia are warranted.

Management of anomia

Anomia is a complex, commonly occurring symptom of aphasia with different underlying causes. A number of behavioral approaches to rehabilitation of anomia have been described. Some are restitutive in nature and attempt to reactivate lexical-semantic or phonological representations to improve word retrieval. Others are intended to reorganize language functions by engaging alternative cognitive systems to mediate word retrieval or by exploiting residual abilities to circumvent the impairment. A better appreciation of the characteristics of an individual's naming deficit may assist the clinician in selecting appropriate interventions for restitution or substitution of function in the management of this disorder.

Cognitive impairment in isolated subtentorial stroke

BACKGROUND

Recent case reports have implicated subtentorial lesions of the brainstem or cerebellum as part of the neurocognitive circuitry.

AIM

To determine whether cognitive impairment is part of the neurological deficit in isolated brainstem (IBSS) or cerebellar stroke (ICS), using bedside screening and formal neurocognitive assessment of higher cortical function.

METHODS

Accrual occurred through a hospital based stroke registry. Cognitive bedside tests and neuropsychological tests were employed for the detection of higher cortical function. Scores from each test were converted to age and education based z-scores. Scores at or below -1.5 SD were clinically defined 'impaired'. Scores were averaged across tests in each functional area.

RESULTS

Of the stroke patients (n = 1360), the infarct was isolated within the brainstem (IBSS) in (45 of 120 or 38%) and isolated within the cerebellum (ICI) in (37 of 79 or 46.8%). Comparison of the IBSS patients with cognitive impairment in one or more domains to those with brainstem (24 of 45 or 53%) and hemispheric cerebral infarcts: (43 of 72 or 58%) (Pearson Chi Square) was not significantly different (P = 0.49). The admission Canadian Neurological Score (mean 10.2, 95% CI: 9.7-10.2) and Rankin score at 1 month (mean 1.7, 95% CI: 2.1-1.4). Comparison of the number of ICI patients with cognitive impairment in one or more domains (13 of 37 or 35.1%) to those with cerebellar and hemispheric cerebral infarcts who had abnormal cognitive testing in one or more domains (16 of 36 or 44.4%) (Pearson Chi Square) was not significantly different (P = 0.41). The mean admission Canadian Neurological Scores for the ICI cases was 10.9 (95% CI: 10.5-11.2) on average. Their mean admission Rankin score was 1.7 (95% CI: 1.4-2.1). Neuropsychological testing for frontal/executive skills, immediate and delayed memory, and visuospatial abilities (n = 15), revealed that frontal abilities were most impacted by the isolated strokes in these patients (average frontal impairment index = -1.29 +/- 0.79) followed by delayed recall of verbal and visual information (mean = -1.18 +/- 1.17). Immediate memory (-0.51 +/- 0.75) and visuoconstructive skills (-0.06 +/- 0.88) were relatively spared. Overall, 47% of the patients showed impairment on frontal tasks while 40% had significant impairment in delayed recall. In contrast, only 13% had scores below the cutoff for immediate memory and none fell below the cutoff for visuoconstructive skills.

CONCLUSION

Cognitive impairment is a common sequel of isolated subtentorial stroke. The frequency of impairment is similar either because of isolated brainstem or isolated cerebellar infarct, and similar to cognitive impairment with cerebral hemispheric lesions. Frontal networks or metacognition is the most frequently involved domain.

New developments in stroke rehabilitation

There is increasing evidence that environmental and neuropharmacologic treatments enhance stroke recovery. Functional magnetic resonance imaging and transcranial magnetic stimulation have significantly broadened our understanding of the neuroanatomic relationships involved in recovery from brain injury due to stroke. These tools have also demonstrated the role for pharmacologic enhancement of cortical plasticity coupled with behavioral interventions. Robot-assisted therapy and partial body weight-supported treadmill gait training have demonstrated the role for technologic intervention in the modern neuro-rehabilitation setting. Current research using hemi-field ocular prisms and patching techniques suggest a role in the rehabilitation of hemianopsia and visual neglect. Finally, many advances have been made in the understanding of common stroke complications, such as depression, dysphagia, venous thromboembolic disease, incontinence, and spasticity.