Is upper limb ischemic conditioning acceptable and feasible in patients with chronic post-stroke aphasia?

Event Abstract Back to Event Perilesional perfusion in chronic stroke-induced aphasia before and after behavioral treatment interventions Matthew Walenski1*, Kaitlyn Litcofsky1, Yufen Chen1, David Caplan2, Swathi Kiran3, Brenda Rapp4, Todd Parrish1 and Cynthia K. Thompson1 1 Northwestern University, United States 2 Massachusetts General Hospital, Harvard Medical School, United States 3 Boston University, United States 4 Johns Hopkins University, United States Introduction. Stroke-induced alterations in cerebral blood flow (perfusion) persist into chronic stages of aphasia, with frequent reports of perilesional hypoperfusion (Brumm et al., 2010; Richardson et al., 2011; Thompson et al., 2010, 2017). However, the relation between chronically reduced perfusion and language (dis-)function and recovery remains unclear (see Kiran and Thompson, 2019, for review). We examined perfusion in chronic aphasia in left hemisphere perilesional and homologous right hemisphere regions in treatment and no-treatment participant groups. Method. Right-handed native-English speakers with chronic aphasia induced by left hemisphere ischemic stroke were recruited from Northwestern University (agrammatism; n=17), Boston University and Massachusetts General Hospital (anomia; n=31), and Johns Hopkins University (dysgraphia; n=24) and pseudorandomly assigned to treatment (n=45) and no-treatment (n=16) groups. Perfusion was measured twice for each participant at baseline and 3-months following. Between scans, treatment group participants received language domain-specific behavioral treatment. Resting perfusion maps were collected using arterial spin labeling MRI. Raw perfusion values from each voxel were averaged across three perilesional rings in the left hemisphere (LH) and their right hemisphere (RH) homologues, from 0–6mm, 6–12mm, and 12–18mm. Mean perfusion values within each ring were normalized to the mean perfusion values of each individual’s right occipital cortex (based on the Harvard-Oxford parcellation). Results. Across all participants (n=72), LH perfusion at baseline testing was significantly lower in the 0–6mm perilesional ring relative to the 6–12mm (FDR corrected q-value = .0002) and 12–18mm rings (q=.0002); the opposite pattern was found in the right hemisphere, with significantly greater perfusion in the 0–6mm ring relative to the 6–12mm and 12–18mm rings (respectively, q=.0006, q=.0002; Figure 1a). Perfusion in the 6–12mm ring did not differ from that in the 12–18mm ring in either hemisphere (qs>.11). Perfusion was also elevated in right hemisphere regions homologous to the lesion, and was not significantly different from the 0–6mm RH ring (t(71)=.12, p=.90; Figure 1b). The abnormal perfusion in the 0–6mm rings did not correlate with baseline measures of language ability in either hemisphere (LH: r(69)=.02, p=.86; RH: r(69)=-.09, p=.44), adjusting for lesion volume. Changes in perfusion over time were not observed in the treatment or no-treatment groups in either hemisphere (all qs>.79; Table 1), despite significant language gains in the treatment group. Moreover, there was no correlation between response to treatment and difference in perfusion for any of the LH perilesional rings or their RH homologues (all qs>.11). Conclusions. These findings indicate that perfusion remains abnormal in the chronic stage of aphasia, with perilesional hypoperfusion in the ipsilesional hemisphere and hyperperfusion in homologous regions of the contralesional hemisphere. Such patterns may reflect an autoregulatory change to altered LH vasculature (Thompson et al., 2017). Importantly however, the abnormal perfusion did not correlate with baseline language deficits, and we did not observe any change in perfusion in response to our behavioral treatment interventions, despite improvement in language performance. Thus, perfusion measures may be of limited utility as biomarkers of language recovery in chronic stage stroke aphasia. Figure 1 Figure 2 Acknowledgements This work was supported by the NIH-NIDCD, Clinical Research Center Grant, P50DC012283 (PI: C. K. Thompson). The authors wish to thank Xue Wang, Elena Barbieri, Sladjana Lukic, and Brianne Dougherty for assistance with data collection and analysis. References Brumm KP, Perthen JE, Liu TT, Haist F, Ayalon L, Love T. (2010). An arterial spin labeling investigation of cerebral blood flow deficits in chronic stroke survivors. Neuroimage, 51:995–1005. doi: 10.1016/j.neuroimage.2010.03.008 Kiran, S & Thompson, CK (2019). Neuroplasticity of language networks in aphasia: Advances, Updates, and Future Challenges. Frontiers in Neuroscience, 10, a295, 1-15. doi: 10.3389/fneur.2019.00295 Richardson JD, Baker JM, Morgan PS, Rorden C, Bonilha L, Fridriksson J. (2011). Cerebral perfusion in chronic stroke: implications for lesion-symptom mapping and functional MRI. Behavioral Neurology, 24:117–22. doi: 10.1155/2011/380810 Thompson CK, den Ouden DB, Bonakdarpour B, Garibaldi K, Parrish TB. (2010). Neural plasticity and treatment-induced recovery of sentence processing in agrammatism. Neuropsychologia, 48:3211–27. doi: 10.1016/j.neuropsychologia.2010.06.036 Thompson CK, Walenski M, Chen Y, Caplan D, Kiran S, Rapp B, et al. (2017). Intrahemispheric perfusion in chronic stroke-induced aphasia. Neural Plasticity, 2017:2361691. doi: 10.1155/2017/2361691 Keywords: chronic aphasia, Stroke, Perfusion, MRI, Treatment Conference: Academy of Aphasia 57th Annual Meeting, Macau, Macao, SAR China, 27 Oct - 29 Oct, 2019. Presentation Type: Poster presentation Topic: Not eligible for student award Citation: Walenski M, Litcofsky K, Chen Y, Caplan D, Kiran S, Rapp B, Parrish T and Thompson CK (2019). Perilesional perfusion in chronic stroke-induced aphasia before and after behavioral treatment interventions. Front. Hum. Neurosci. Conference Abstract: Academy of Aphasia 57th Annual Meeting. doi: 10.3389/conf.fnhum.2019.01.00064 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 06 May 2019; Published Online: 09 Oct 2019. * Correspondence: Mx. Matthew Walenski, Northwestern University, Evanston, United States, mwalenski@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson Google Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson Google Scholar Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson PubMed Matthew Walenski Kaitlyn Litcofsky Yufen Chen David Caplan Swathi Kiran Brenda Rapp Todd Parrish Cynthia K Thompson Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

FV 13 Electrophysiological correlates of language recovery – an MEG study of neuroplasticity in chronic post stroke aphasia

Sir, Endotracheal tube (ETT) cuff pressure management is an essential part of airway management in intubated and mechanically ventilated patients. Cuff pressures in the intubated patients in hospitals and Intensive Care Units are often too high. Acceptable cuff pressures are best achieved when a cuff pressure manometer has been used. Obstruction to mucosal blood flow occurs at pressures above 30 cm H2O, with total occlusion of flow at 50 cm H2O.[1] Commercially available cuff inflators are costly. The use of this crucial equipment is neglected and is often not available in many hospitals or hospital areas of economically poor countries. We have devised a cuff inflator and cuff pressure measuring device with readily available materials [Figure 1]. These include an airway low pressure manometer detached from an old unused Bird ventilator with a reading up to 100 cm H2O pressure. As an alternative, low cost commercially available low pressure monitor can also be made use of. Other spares include cuff inflating one-way valve cut from Foley's catheter, a 3-way connector and other easily available connectors. All the parts were bonded with the help of quick fix sealant and tested for air leak in a bowl of water. We tested the accuracy of the device by connecting it to mercury manometer and also commercially available Portex® cuff inflator which matched with the readings with an error as low as 2–3 cm H2O in the clinical range of 20–35 cm H2O. Keeping this small error into account we are practically using the device regularly both for ETT cuff and laryngeal mask airway (LMA) cuff. We have already used it in 80 cases to check the ETT cuff pressure and for inflating cuff of pro-seal LMA to the required pressure in 60 patients. Figure 1 The assembled cuff inflator and cuff pressure monitor connected to endotracheal tube (a) and its calibration (b) The incidence and severity of tracheal mucosal lesions increase with cuff pressure >30 cm H2O. It is revealed that the majority of cuff pressures exceeded safe pressure and required correction.[2] The pressure exerted on the trachea must be maintained within a range (25–30 cm H2O or 18–22 mmHg) to ensure perfusion to the tracheal capillaries without causing injury.[3] Only 27% of pressures were within 20–30 cm H2O; 27% exceeded 40 cm H2O. Hence, it is recommended that endotracheal cuff pressure be set and monitored with a manometer.[4] It is important to perform cuff pressure measurements at 6–12 hourly intervals and to use the correct method. At the time of periodic pressure check while connecting any cuff inflator to the ETT valve, loss of cuff pressure of about 6.6 cm H2O can occur on an average needing reinflation to adjust for pressure loss.[5] However, our device has the advantage that it can be pre-pressurized with the help of 3-way connector of the assembly before pressure check which can prevent cuff pressure loss and deflation. Our low cost cuff pressure inflator can be easily constructed and can be practically used. Innovative practice and translational research is an important aspect of higher education and postgraduate curriculum. It can be a useful as an aid in innovative teaching methodology to teach basic foundations in anaesthesiology by giving such projects to postgraduate students to imbibe spirit of creativity.

BackgroundTo investigate the influence of galantamine on linguistic function, any associated factors in patients with chronic post-stroke aphasia were analysed.Methods45 patients younger than 75 years with chronic aphasia (≥1 year...

Continuous theta burst stimulation over right pars triangularis facilitates naming abilities in chronic post-stroke aphasia by enhancing phonological access

Introduction: Previous studies indicate that anodal transcranial Direct Current Stimulation (A-tDCS) to left hemisphere or cathodal tDCS (C-tDCS) to right hemisphere might augment aphasia therapy to facilitate language recovery after chronic stroke and that cerebellar tDCS can augment verbal fluency and learning in healthy controls. Hypothesis: A-tDCS or C-tDCS) plus naming therapy results in improved naming performance for trained and untrained items from baseline to post-treatment compared to sham plus naming therapy in chronic aphasia. Methods: Six patients with large, chronic left middle cerebral artery (MCA) ischemic stroke and one patient with large bilateral MCA strokes participated in a randomized, double-blind, sham controlled, within-subject crossover trial (15 sessions of sham + naming therapy and 15 sessions of tDCS + naming therapy, in random order, separated by 2 months). 4 patients were randomly assigned to A-tDCS and 3 patients were assigned to C-tDCS. We used 2 mA for stimulation over right cerebellum for the first 20 minutes of computer-delivered naming therapy. Within-subjects within-treatments analysis using McNemar’s test for correlated responses to evaluate gains from each of the treatment conditions. An alpha level of p<0.05 was considered significant. Results: tDCS + naming treatment produced significant gains in naming of both trained and untrained items in 3/4 patients with anodal stimulation and 3/3 patients with cathodal treatment. Sham + naming treatment produced gains for only trained items, and only in 4/7 participants. Discussion: A-tDCS or C-tDCS improved generalization of improvements to untrained stimuli after naming therapy for most patients. Results indicate potential usefulness of right cerebellar tDCS to augment naming therapy after chronic post stroke aphasia with large left or bilateral lesions.

ObjectiveRecent evidence has fuelled the debate on the role of massed practice in the rehabilitation of chronic post-stroke aphasia. Here, we further determined the optimal daily dosage and total duration...

Background and aimAphasia as a common consequence of stroke, is an acquired neurologic communication disorder that can affect symbol language processing. Different types of intervention approaches have been introduced. Multimodal Communication Program (MCP) is a new augmentative alternative communication approach in chronic aphasia. The aim of this study was to investigate the effect of MCP on communication skills of patients with chronic aphasia.MethodsThis prospective, single subject, A-B-A design study was done during 2016 in Semnan, Iran. Participants were two patients with severe aphasia with a single left-hemisphere stroke. Three phases, including baseline, intervention and follow-up were administered. The patients received nine-hour intervention, over 10 working days.ResultsThree different scores were calculated for each patient: verbal efforts, the frequency of each modality and the accuracy of switching between modalities and the reaction time. The frequency of verbal modality increased for both patients. They could switch between modalities more successfully than before the intervention. The results for the reaction time, however were challenging. The onset reaction time decreased for patient 1, and increased during switching between modalities, and patient 2 showed the opposite.ConclusionThe MCP can improve the communication skills in patients with chronic post stroke aphasia. However, some factors, such as reduction of the patients’ reaction time is probably related to the amount of allocated resources during intervention.Trial registrationThe trial was registered at IRCT center with ID: IRCT2016032325194N3.FundingThe study was financed by Semnan University of Medical Sciences (Grant no.: A-10-333-3).

Purpose The influential relationship between executive functioning and aphasia rehabilitation outcomes has been addressed in a number of studies, but few have studied the effect of adding executive function training to linguistic therapies. The present study aimed to measure the effects of combining, within therapy sessions, executive function training and anomia therapy on naming and discourse abilities in people with chronic aphasia. Method A single-case experimental design with multiple baselines across participants was used. Four persons with chronic post-stroke aphasia received 12 sessions of a tailored treatment combining executive function training and semantic feature analysis (SFA) therapy. Naming accuracy of treated items was examined over the course of the treatment while control naming scores of untreated items and discourse measures were collected pre-treatment, immediately post-treatment, and 4 weeks post-treatment, in order to investigate the multidimensional effects of the treatment and their maintenance. Result Naming skills improved in all participants for treated and untreated items, were maintained over time, and were accompanied by improved discourse abilities. Visual and statistical analyses showed a significant treatment effect for naming skills in three out of the four participants. Conclusion A combination of executive function training and SFA treatment in people with chronic aphasia may improve both naming skills and discourse efficiency. Further studies are needed to substantiate these promising preliminary results.

The aim of this study was to investigate the effect of different mechanical behaviour of the brachial artery on blood pressure (BP) measurements during cuff inflation and deflation. BP measurements were taken from each of 40 participants, with three repeat sessions under three randomized cuff deflation/inflation conditions. Cuff pressure was linearly deflated and inflated at a standard rate of 2-3 mmHg/s and also linearly inflated at a fast rate of 5-6 mmHg/s. Manual auscultatory systolic and diastolic BPs, and pulse pressure (SBP, DBP, PP) were measured. Automated BPs were determined from digitally recorded cuff pressures by fitting a polynomial model to the oscillometric pulse amplitudes. The BPs from cuff deflation and inflation were then compared. Repeatable measurements between sessions and between the sequential order of inflation/deflation conditions (all P > 0.1) indicated stability of arterial mechanical behaviour with repeat measurements. Comparing BPs obtained by standard inflation with those from standard deflation, manual SBP was 2.6 mmHg lower (P < 0.01), manual DBP was 1.5 mmHg higher (P < 0.01), manual PP was 4.2 mmHg lower (P < 0.001), automated DBP was 6.7 mmHg higher (P < 0.001) and automatic PP was 7.5 mmHg lower (P < 0.001). There was no statistically significant difference for any automated BPs between fast and standard cuff inflation. The statistically significant BP differences between inflation and deflation suggest different arterial mechanical behaviour between arterial opening and closing during BP measurement. We have shown that the mechanical behaviour of the brachial artery during BP measurement differs between cuff deflation and cuff inflation.

Objective: We have previously demonstrated that recording onset and termination of Korotkoff sounds as markers of systolic (SBP) and diastolic (DBP) during brachial cuff deflation results in underestimation of true SBP. In this study we explore whether recording Korotkoff sounds during cuff inflation provides more accurate non-invasive estimates of intra-arterial blood pressure (IABP). Design and method: Experiments were carried out on 15 participants, (14 males, 64.3 ± 10.4 years; one female, 86 yo), undergoing coronary angiography. A conventional (oscillometric) BP cuff, with a microphone for Korotkoff sounds, was placed on the upper arm. The cuff was inflated at rate of approximately 2.5mm Hg/sec and deflated at the same rate. Inflation and deflation cycles were randomised and separated by 2 - 3 minutes. IABP was measured below the cuff with a fluid-filled catheter inserted via the radial artery and an external transducer. Korotkoff sounds were processed electronically, and custom algorithms identified the cuff pressure (CP) at which the first and last Korotkoff sounds were heard. Results: Systolic (SBP), and diastolic (DBP) pressure were 147.7.6 ± 12.7 and 70.7 ± 9.7mmHg. The CP at which the brachial artery closes during rapid (∼20mmHg/sec) cuff inflation (132.0 ± 17.1) was similar to that of slow (2.5mmHg/sec) inflation (132.0 ± 16.3 mmHg). However, peak Korotkoff sound energy was significantly reduced (P = 0.003) from 0.19 ± 0.1 to 0.15 ± 0.09 RMS volts and the Korotkoff sounds were often observed to disappear prematurely before brachial artery closure. Difference between intra-arterial SBP and CP at the last recorded Korotkoff sound (27.5 ± 9.3 mmHg) during cuff inflation was significantly higher (P = 0.0025) than during slow cuff deflation (18.9 ± 8.3 mmHg). In contrast, DBP recorded at first onset of the Korotkoff sounds (70.5 ± 11.1 mmHg) was consistently similar to intra-arterial DBP (70.7 ± 9.7 mmHg). Conclusions: SBP estimates derived from the last Korotkoff sound recorded as the cuff inflates generates greater errors than when Korotkoff sounds are first recorded as the cuff deflates. In contrast, the estimate of DBP derived from the first onset of the Korotkoff sound as the cuff inflates, appears to reflect accurately the true intra-arterial DBP.

Introduction: Brachial artery flow mediated dilation (FMD) is a well-established measure of vascular endothelial health and is pathologically low in chronic stroke survivors. Ischemic conditioning (IC) is a cardioprotective stimulus and has been shown to improve FMD and enhance motor function in healthy humans. We recently showed that IC can improve paretic muscle strength and increase self-selected walking speed in stroke survivors. These improvements could be, in part, mediated by improved peripheral vascular function and increased blood flow to the exercising muscle. The effects of IC on vascular endothelial function post-stroke have not been investigated. Hypothesis: Two weeks of IC on the paretic leg of chronic stroke survivors will improve FMD in the non-paretic brachial artery. Methods: This was a prospective, randomized, blinded and controlled pilot study. Twenty chronic stroke survivors (&gt;1-year post-stroke) received either IC (cuff inflation on the paretic leg for five minutes to 225 mmHg) or Sham IC (cuff inflation to 10 mmHg) every other day for two weeks (five on-off cycles per session). Brachial artery FMD was assessed using ultrasonography within 48 hours of the beginning and end of the intervention period. Results: Eight men and twelve women participated in this study. The mean age was 59 ± 16 years and the mean time post-stroke was 9 ± 9 years. Brachial artery FMD increased in the IC group from 6.2 ± 4.9% to 8.9 ± 3.9% (n=10; p=0.023, 2-way Repeated Measures ANOVA) while no change was observed in the Sham IC group (pre- vs. post = 3.8 ± 3.9% vs. 2.7 ± 3.1%, respectively; p=0.32, n=10). Expressed as the mean change in FMD, IC increased FMD by 2.8 ± 3.7% while no change was observed in the Sham IC group (delta FMD = -1.1 ± 3.4%; p=0.024 IC vs. IC Sham, unpaired t-test). Conclusions: Two weeks of IC increases brachial artery FMD in chronic stroke survivors. Taken together with our previous work that shows IC increases paretic muscle strength and walking speed in chronic stroke survivors, IC has the potential to improve both motor and cardiovascular function post-stroke. Future larger studies are needed to evaluate the efficacy of IC to improve stroke recovery and to identify the pathways involved which confer benefit to both the nervous and cardiovascular systems.

Objectives. In this study, we test the hypothesis that if, as demonstrated in a previous study, brachial arteries exhibit hysteresis as the occluding cuff is deflated and fail to open until cuff pressure (CP) is well below true intra-arterial blood pressure (IAPB), estimating systolic (SBP) and diastolic blood pressure (DBP) from the presence of Korotkoff sounds (KS) as CP increases may eliminate these errors and give more accurate estimates of SBP and DBP relative to IABP readings. Approach. In 62 subjects of varying ages (45.1 ± 19.8, range 20.6–75.8 years), including 44 men (45.3 ± 19.4, range 20.6–75.8 years) and 18 women (44.4 ± 21.4, range 20.9–75.3 years), we sequentially recorded SBP and DBP both during cuff inflation and cuff deflation using KS. Results. There was a significant (p < 0.0001) increase in SBP from 122.8 ± 13.2 to 127.6 ± 13.0 mmHg and a significant (p = 0.0001) increase in DBP from 70.0 ± 9.0 to 77.5 ± 9.7 mmHg. Of the 62 subjects, 51 showed a positive increase in SBP (0–14 mmHg) and 11 subjects showed a reduction (−0.3 to −7 mmHg). The average differences for SBP and DBP estimates derived as the cuff inflates and those derived as the cuff deflates were 4.8 ± 4.6 mmHg and 2.5 ± 4.6 mmHg, not dissimilar to the differences reported between IABP and non-invasive blood pressure measurements. Although we could not develop multiparameter linear or non-linear models to explain this phenomenon we have clearly demonstrated through ANOVA tests that both body mass index (BMI) and pulse wave velocity are implicated, supporting the hypothesis that the phenomenon is associated with age, higher BMI and stiffer arteries. Significance. The implications of this study are that brachial sphygmomanometry carried out during cuff inflation could be more accurate than measurements carried out as the cuff deflates. Further research is required to validate these results with IAPB measurements.

Haemostatic changes caused by i.v. regional anaesthesia with lignocaine

Associations among depression, demographic variables, and language impairments in chronic post-stroke aphasia