Jessica M. Cassidy

Primed low-frequency repetitive transcranial magnetic stimulation and constraint-induced movement therapy in pediatric hemiparesis: a randomized controlled trial.

The aim of this study was to determine the feasibility and efficacy of five treatments of 6 Hz primed, low‐frequency, repetitive transcranial magnetic stimulation (rTMS) combined with constraint‐induced movement therapy (CIMT) to promote recovery of the paretic hand in children with congenital hemiparesis.

Spontaneous and Therapeutic-Induced Mechanisms of Functional Recovery After Stroke

With increasing rates of survival throughout the past several years, stroke remains one of the leading causes of adult disability. Following the onset of stroke, spontaneous mechanisms of recovery at the cellular, molecular, and systems levels ensue. The degree of spontaneous recovery is generally incomplete and variable among individuals. Typically, the best recovery outcomes entail the restitution of function in injured but surviving neural matter. An assortment of restorative therapies exists or is under development with the goal of potentiating restitution of function in damaged areas or in nearby ipsilesional regions by fostering neuroplastic changes, which often rely on mechanisms similar to those observed during spontaneous recovery. Advancements in stroke rehabilitation depend on the elucidation of both spontaneous and therapeutic-driven mechanisms of recovery. Further, the implementation of neural biomarkers in research and clinical settings will enable a multimodal approach to probing brain state and predicting the extent of post-stroke functional recovery. This review will discuss spontaneous and therapeutic-induced mechanisms driving post-stroke functional recovery while underscoring several potential restorative therapies and biomarkers.

Serial treatments of primed low-frequency rTMS in stroke: characteristics of responders vs. nonresponders.

PURPOSE This study analyzed the characteristics of responders vs. nonresponders in people with stroke receiving a novel form of repetitive transcranial magnetic stimulation (rTMS) to improve hand function. METHODS Twelve people with stroke received five treatments of 6-Hz primed low-frequency rTMS to the contralesional primary motor area. We compared demographic factors, clinical features, and the ipsilesional/contralesional volume ratio of selected brain regions in those who improved hand performance (N = 7) on the single-hand component of the Test Évaluant la performance des Membres supérieurs des Personnes Âgées (TEMPA) and those who showed no improvement (N = 5). RESULTS Responders showed significantly greater baseline paretic hand function on the TEMPA, greater preservation volume of the ipsilesional posterior limb of the internal capsule (PLIC), and lower scores (i.e., less depression) on the Beck Depression Inventory than nonresponders. There were no differences in age, sex, stroke duration, paretic side, stroke hemisphere, baseline resting motor threshold for ipsilesional primary motor area (M1), NIH Stroke Scale, Upper Extremity Fugl-Meyer, Mini-Mental State Examination, or preservation volume of M1, primary somatosensory area, premotor cortex, or supplementary motor area. CONCLUSION Our results support that preserved PLIC volume is an important influential factor affecting responsiveness to rTMS.

Priming the Brain to Capitalize on Metaplasticity in Stroke Rehabilitation

Repetitive transcranial magnetic stimulation (rTMS) is emerging as a potentially valuable intervention to augment the effects of behavioral therapy for stroke. When used in conjunction with other therapies, rTMS embraces the concept of metaplasticity. Due to homeostatic mechanisms inherent to metaplasticity, interventions known to be in isolation to enhance excitability can interact when applied successively under certain timing conditions and produce enhanced or opposite effects. Similar to “muscular wisdom,” with its self-protective mechanisms, there also appears to be “synaptic wisdom” in neural networks with homeostatic processes that prevent over- and under-excitability. These processes have implications for both enhancing and suppressing the excitability effects from behavioral therapy. The purpose of this article is to relate the concept of metaplasticity, as derived from studies in humans who are healthy, to stroke rehabilitation and consider how it can be leveraged to maximize stroke outcomes.

Safety of Primed Repetitive Transcranial Magnetic Stimulation and Modified Constraint-Induced Movement Therapy in a Randomized Controlled Trial in Pediatric Hemiparesis

OBJECTIVE To investigate the safety of combining a 6-Hz primed low-frequency repetitive transcranial magnetic stimulation (rTMS) intervention in the contralesional hemisphere with a modified constraint-induced movement therapy (mCIMT) program in children with congenital hemiparesis. DESIGN Phase 1 randomized, double-blinded, placebo-controlled pretest/posttest trial. SETTING University academic facility and pediatric specialty hospital. PARTICIPANTS Subjects (N = 19; age range, 8-17 y) with congenital hemiparesis caused by ischemic stroke or periventricular leukomalacia. No subject withdrew because of adverse events. All subjects included completed the study. INTERVENTIONS Subjects were randomized to 1 of 2 groups: either real rTMS plus mCIMT (n = 10) or sham rTMS plus mCIMT (n = 9). MAIN OUTCOME MEASURES Adverse events, physician assessment, ipsilateral hand function, stereognosis, cognitive function, subject report of symptoms assessment, and subject questionnaire. RESULTS No major adverse events occurred. Minor adverse events were found in both groups. The most common events were headaches (real: 50%, sham: 89%; P = .14) and cast irritation (real: 30%, sham: 44%; P = .65). No differences between groups in secondary cognitive and unaffected hand motor measures were found. CONCLUSIONS Primed rTMS can be used safely with mCIMT in congenital hemiparesis. We provide new information on the use of rTMS in combination with mCIMT in children. These findings could be useful in research and future clinical applications in advancing function in congenital hemiparesis.

Interhemispheric Inhibition Measurement Reliability in Stroke: A Pilot Study

Reliable transcranial magnetic stimulation (TMS) measures for probing corticomotor excitability are important when assessing the physiological effects of noninvasive brain stimulation. The primary objective of this study was to examine test‐retest reliability of an interhemispheric inhibition (IHI) index measurement in stroke.

Ipsilesional motor-evoked potential absence in pediatric hemiparesis impacts tracking accuracy of the less affected hand.

This study analyzed the relationship between electrophysiological responses to transcranial magnetic stimulation (TMS), finger tracking accuracy, and volume of neural substrate in children with congenital hemiparesis. Nineteen participants demonstrating an ipsilesional motor-evoked potential (MEP) were compared with eleven participants showing an absent ipsilesional MEP response. Comparisons of finger tracking accuracy from the affected and less affected hands and ipsilesional/contralesional (I/C) volume ratio for the primary motor cortex (M1) and posterior limb of internal capsule (PLIC) were done using two-sample t-tests. Participants showing an ipsilesional MEP response demonstrated superior tracking performance from the less affected hand (p=0.016) and significantly higher I/C volume ratios for M1 (p=0.028) and PLIC (p=0.005) compared to participants without an ipsilesional MEP response. Group differences in finger tracking accuracy from the affected hand were not significant. These results highlight differentiating factors amongst children with congenital hemiparesis showing contrasting MEP responses: less affected hand performance and preserved M1 and PLIC volume. Along with MEP status, these factors pose important clinical implications in pediatric stroke rehabilitation. These findings may also reflect competitive developmental processes associated with the preservation of affected hand function at the expense of some function in the less affected hand.

Neuroimaging Identifies Patients Most Likely to Respond to a Restorative Stroke Therapy

Background and Purpose— Patient heterogeneity reduces statistical power in clinical trials of restorative therapies. Valid predictors of treatment responsiveness are needed, and several have been studied with a focus on corticospinal tract (CST) injury. We studied performance of 4 such measures for predicting behavioral gains in response to motor training therapy. Methods— Patients with subacute-chronic hemiparetic stroke (n=47) received standardized arm motor therapy, and change in arm Fugl-Meyer score was calculated from baseline to 1 month post-therapy. Injury measures calculated from baseline magnetic resonance imaging included (1) percent CST overlap with stroke, (2) CST-related atrophy (cerebral peduncle area), (3) CST integrity (fractional anisotropy) in the cerebral peduncle, and (4) CST integrity in the posterior limb of internal capsule. Results— Percent CST overlap with stroke, CST-related atrophy, and CST integrity did not correlate with one another, indicating that these 3 measures captured independent features of CST injury. Percent injury to CST significantly predicted treatment-related behavioral gains (r=−0.41; P=0.004). The other CST injury measures did not, neither did total infarct volume nor baseline behavioral deficits. When directly comparing patients with mild versus severe injury using the percent CST injury measure, the odds ratio was 15.0 (95% confidence interval, 1.54–147; P<0.005) for deriving clinically important treatment-related gains. Conclusions— Percent CST injury is useful for predicting motor gains in response to therapy in the setting of subacute-chronic stroke. This measure can be used as an entry criterion or a stratifying variable in restorative stroke trials to increase statistical power, reduce sample size, and reduce the cost of such trials.

Other health professions

Children and adults with intellectual and developmental disabilities (IDD) should live healthy, safe and fully integrated lives in communities of their choice. Many professionals are involved in support and services to cater to individual needs and what is most important, support their family and the members of their support network. People who have IDD also often have co-occurring disorders that result in complex needs and support. Primary health care providers need to understand the professions, educational backgrounds and roles of the many other professionals that are a part of an individual’s health, allied health and broad support team. This chapter is designed to provide this important information about the most common professions that deliver services and support to people with IDD.

Primed low-frequency repetitive transcranial magnetic stimulation and constraint-induced movement therapy in pediatric hemiparesis: a randomized trial

The aim of this study was to determine the feasibility and efficacy of five treatments of 6 Hz primed, low‐frequency, repetitive transcranial magnetic stimulation (rTMS) combined with constraint‐induced movement therapy (CIMT) to promote recovery of the paretic hand in children with congenital hemiparesis.