Promoting physical activity in hospitalized patients with mild ischemic stroke: a pilot study

Background: Patients with acute stroke spend most of their hospital day inactive. However, a method to promote physical activity (PA) in stroke has not been established.

Objective: To evaluate the effectiveness of promoting PA by enhancing self-efficacy in hospitalized patients with mild ischemic stroke.

Design: Pre–post interventional study.

Methods: Hospitalized patients with mild ischemic stroke who could walk without assistance were recruited. We measured the daily number of steps taken as the index of daily hospitalized PA using an accelerometer. At the baseline measurement, patients did not receive accelerometer-based feedback. To promote hospitalized PA, a physical therapist provided instruction on the self-monitoring approach and discussed PA targets, encouraged the patients to walk more, and instructed them on the importance of PA after stroke. We also measured self-efficacy for PA using an assessment tool at the baseline and during the intervention.

Results: Twenty-two patients (62.5 years old, 68.2% men) were included. PA during the intervention was higher than that at the baseline measurement (5709.4 ± 2236.1 vs. 2813.9 ± 1511.9 steps/day, p < 0.001). Self-efficacy for PA during the intervention was also higher than that at the baseline measurement (76.4 ± 18.8 vs. 58.9 ± 29.0 points, p < 0.001).

Conclusions: Promoting PA by enhancing self-efficacy may increase PA and self-efficacy for PA in hospitalized patients with mild ischemic stroke. The present results might provide new strategies of PA promotion in these hospitalized patients.     

Effects of constraint-induced movement therapy for lower limbs on measurements of functional mobility and postural balance in subjects with stroke: a randomized controlled trial*

Background: Constraint-induced movement therapy (CIMT) is suggested to reduce functional asymmetry between the upper limbs after stroke. However, there are few studies about CIMT for lower limbs.

Objective: To examine the effects of CIMT for lower limbs on functional mobility and postural balance in subjects with stroke.

Methods: A 40-day follow-up, single-blind randomized controlled trial was performed with 38 subacute stroke patients (mean of 4.5 months post-stroke). Participants were randomized into: treadmill training with load to restraint the non-paretic ankle (experimental group) or treadmill training without load (control group). Both groups performing daily training for two consecutive weeks (nine sessions) and performed home-based exercises during this period. As outcome measures, postural balance (Berg Balance Scale – BBS) and functional mobility (Timed Up and Go test – TUG and kinematic parameters of turning – Qualisys System of movement analysis) were obtained at baseline, mid-training, post-training and follow-up.

Results: Repeated-measures ANOVA showed improvements after training in postural balance (BBS: F = 39.39, P < .001) and functional mobility, showed by TUG (F = 18.33, P < .001) and by kinematic turning parameters (turn speed: F = 35.13, P < .001; stride length: F = 29.71, P < .001; stride time: F = 13.42, P < .001). All these improvements were observed in both groups and maintained in follow-up.

Conclusions: These results suggest that two weeks of treadmill gait training associated to home-based exercises can be effective to improve postural balance and functional mobility in subacute stroke patients. However, the load addition was not a differential factor in intervention.     

The vascularization pattern of acellular nerve allografts after nerve repair in Sprague-Dawley rats

Objective: We have demonstrated that angiogenesis in acellular nerve allografts (ANAs) can promote neuroregeneration. The present study aimed to investigate the microvascular regeneration pattern of ANAs in Sprague-Dawley (SD) rats.

Methods: Sixty male SD rats were randomly divided into an autologous group and a rat acellular nerve allograft group (rANA), and 10-mm sciatic nerve defects were induced in these rats. On the 7th, 14th and 21st days after surgery, systemic perfusion with Evans Blue (EB) or lead oxide was performed on the rats through carotid intubation. Samples were then collected for gross observation, and the microvessels in the nerves were reconstructed through microscopic CT scans using MIMICS software. The vascular volume fraction (VF, %) and microvessel growth rate (V, mm/d) in both groups were then measured, and 1 month after surgery, NF-200 staining was performed to observe and compare the growth condition of the axons.

Results: Early post-operative perfusion with gelatin/EB showed EB permeation around the acellular nerve. Perfusion with gelatin/lead oxide showed that the blood vessels had grown into the allograft from both ends 7 days after the operation. Fourteen days after the operation, the microvessel growth rate of the autologous group was faster than that of the rANA group (0.39 ± 0.17 mm/d vs. 0.26 ± 0.14 mm/d, p < 0.05), and the vascular VF was also higher than that of the rANA group (8.92% ± 1.54% vs. 6.31% ± 1.21%, p < 0.05). Twenty-one days after the operation, the blood vessels at both ends of the allograft had connected to form a microvessel network. The growth rate was not significantly different between the two groups; however, the vascular VF of the autologous group was higher than that of the rANA group (12.18% ± 2.27% vs. 9.92% ± 0.84%, p < 0.05). One month after the operation, the NF-200 fluorescence (IOD) in the autologous group significantly increased compared with that of the rANA group (540,278 ± 17,424 vs. 473,310 ± 14,636, respectively, p < 0.05), suggesting that the results of the repair after nerve injury were significantly better in the autologous group than in the rANA group.

Conclusion: Both the autologous nerve and ANAs rely on the permeation of tissue fluids to supply nutrients during the early stage, and microvessel growth mainly starts at both ends of the graft and enters the graft along the long axis. Compared to ANAs, the growth speed of revascularization in autologous nerve grafts was faster, leading to a better outcome in the autologous nerve group.     

Intraluminal spindle-shaped-head suture induced occlusion of middle cerebral artery in the rats

Objective: This study aimed to introduce a modified animal model of middle cerebral arterial occlusion (MCAO) through placement of intraluminal spindle-shaped head suture by comparing the traditional MCAO model.

Methods: A total of 60 male Spraque-Dawley (SD) rats were divided into two groups and MCAO was induced using spindle-shaped head suture or round head suture. The mortality, infarct volume, neurological function, success rate of the surgery, and stability of modeling were examined to evaluate the effectiveness of this model.

Results: Our results showed the success rate was 90.0% in spindle-shaped head group and 83.3% in round head group showing no significant difference; spindle-shaped head achieved a better establishment of MCAO model as shown in neurological examination. The infarct volume was 31.99 ± 5.44% in spindle-shaped head group and was significantly higher than in round head group (24.59 ± 7.17%; p < 0.05), and the coefficient of variation of infarct volume in spindle-shaped head group was lower than in round head group.

Conclusion: Our findings indicate that the modified suture induces a more reproducible and stable ischemic stroke following MCAO in SD rats.     

The use of virtual reality for balance among individuals with chronic stroke: a systematic review and meta-analysis

Background: Virtual reality (VR) is becoming a popular alternative to traditional upper and lower limb rehabilitation following a stroke.

Objective: To conduct a systematic review and meta-analysis on the effectiveness of VR interventions for improving balance in a chronic stroke (≥6 months) population.

Data sources: A literature search of Pubmed, Scopus, CINAHL, Embase, Psycinfo, and Web of Science databases was conducted.

Study selection: English randomized controlled trials published up to September 2015 assessing balance with VR in chronic stroke participants.

Data extraction: Mean and standard deviations from outcome measures were extracted. Pooled standard mean differences ± standard error were calculated for the Berg Balance Scale (BBS) and the Timed Up and Go test (TUG).

Results: In total, 20 studies were selected which assessed the Nintendo^® Wii Fit balance board (n = 7), treadmill training and VR (n = 7), and postural training using VR (n = 6). Significant improvements were found for VR interventions evaluating the BBS (n = 12; MD = 2.94 ± 0.57; p < 0.001) and TUG (n = 13; MD = 2.49 ± 0.57; p < 0.001). Sub-analyses revealed postural VR interventions had a significant effect on BBS (n = 5) and TUG (n = 3) scores (BBS: MD = 3.82 ± 0.79; p < 0.001 and TUG: MD = 3.74 ± 0.97; p < 0.001). VR and treadmill training (n = 5) had a significant effect on TUG scores (MD = 2.15 ± 0.89, p = 0.016).

Conclusion: Overall, VR interventions compared to conventional rehabilitation had significant improvements. The meta-analyses also suggest that the Nintendo^® Wii Fit balance board may not be effective, although further confirmatory studies are necessary. Results should be interpreted with caution due to differences in therapy intensities and effect sizes within the included studies.     

Neuroprotective effect of G14-humanin on global cerebral ischemia/reperfusion by activation of SOCS3 – STAT3 – MCL–1 signal transduction pathway in rats

Objective: Humanin (HN) has been identified to suppress neuron death. Gly¹⁴-HN (HNG), as a variant of HN, can decrease infarct volume after ischemia/reperfusion (I/R) injury. This study aimed to investigate the neuroprotective mechanism of HNG on global cerebral I/R (GI) in rats.

Methods: Rats were randomly divided into 13 groups: Sham group, GI groups and HNG groups. Both GI group and HNG groups included six time points (1, 3, 6, 12, 24, and 72 h). At 24 h after reperfusion, Nissl staining was used to observe positive neurons, and p-STAT3, MCL-1, SOCS3, Bax and Caspase-3 in different groups were detected by immunohistochemistry. qRT-PCR and western blot were used to evaluate the expression of STAT3, p-STAT3, MCL–1, and SOCS3.

Results: The immunohistochemistry also showed a significant increase in Bax (0.29 ± 0.007 vs. 0.22 ± 0.007, P < 0.01) and Caspase-3 (0.24 ± 0.02 vs. 0.18 ± 0.006, P < 0.01) in GI group compared with Sham group, while Bax (0.26 ± 0.01 vs. 0.29 ± 0.008, P < 0.01) and Caspase-3 (0.20 ± 0.008 vs. 0.24 ± 0.02, P < 0.01) were significantly decreased by HNG-treatment compared with GI group. Along with immunohistochemistry, western blot and qRT-PCR indicated that the protein and mRNA levels of STAT3, MCL-1, and SOCS3 were up-regulated after administration of HNG at six time points after global cerebral I/R in rat.

Conclusion: HNG might exert neuroprotective effects through alleviating apoptosis and activating of SOCS3 – STAT3 – MCL-1 signal transduction pathway.

Highlights

(1) Cerebral ischemia led to neuronal loss in hippocampal CA1 region of rats.

(2) HNG had neuroprotective effects on ischemia/reperfusion rats.

(3) The protective effect of HNG might be related to the SOCS3 – STAT3 – MCL-1 pathway.

     

Blood pressure evolution in young patients with acute ischemic stroke: a new model for understanding the natural course of spontaneous hypertension?

Background: Approximately 80% of patients suffering an acute ischemic stroke develop transient hypertension. The physiopathological mechanism remains unclear. Due to the lack of vascular risk factors, young adults could be a useful model for understanding blood pressure (BP) evolution in this setting.

Methods: Patients between 18 and 55 years old admitted with an acute ischemic stroke were included. BP was evaluated during the following 48 h. Hypertension was defined as: systolic blood pressure (SBP) ≥140 mmHg or diastolic blood pressure (DBP) ≥90 mmHg. Patients were divided into two groups: RF group included those who had a previous vascular risk factor and/or other medical condition known to affect the autonomic function; noRF group included patients without any of the previously stated conditions.

Results: Thirty-nine patients were included: mean age: 44.26 years old, 21 were males (53.8%). Mean SBP and DBP at admission were 139.77 ± 5.35 mmHg (range: 90–243) and 84.44 ± 3.02 mmHg (range: 60–128), respectively; 43.58% patients were hypertensive at admission. SBP decreased significantly during the first 48 h (p = 0.044) for the entire population. RF group has higher SBP (p = 0.009) and DBP (p = 0.011) at admission than the noRF group.

Conclusion: Most patients were normotensive at admission and BP fell spontaneously despite BP at admission. Young patients without medical conditions that could alter the autonomic system function could be a useful model for understanding acute hypertension in ischemic stroke.     

The association between high on-treatment platelet reactivity and early recurrence of ischemic events after minor stroke or TIA

Objectives: To evaluate the role of HTPR in predicting early recurrence of ischemic events in patients with minor ischemic stroke or high-risk TIA.

Methods: From January 2014 to September 2014, a single center continuously enrolled patients with minor ischemic stroke or high-risk TIA and gave them antiplatelet therapy consisting of aspirin with clopidogrel. HTPR was assessed by TEG after 7 days of antiplatelet therapy and detected CYP2C19 genotype. The incidence of recurrent ischemic events was assessed 3 months after onset. The incidence of recurrent ischemic events was compared between the HTPR and NTPR groups with the Kaplan-Meier method, and multivariate Cox proportional hazards models were used to determine the risk factors associated with recurrent ischemic events.

Results: We enrolled 278 eligible patients with minor ischemic stroke or high-risk TIA. Through TEG testing, patients with HTPR were 22.7%, and carriers were not associated with HTPR to ADP by TEG-ADP(%) (p = 0.193). A total of 265 patients completed 3 months of follow-up, and Kaplan-Meier analysis showed that patients with HTPR had a higher percentage of recurrent ischemic events compared with patients with NTPR (p = 0.002). In multivariate Cox proportional hazards models, history of ischemic stroke or TIA (HR 4.45, 95% CI 1.77–11.16, p = 0.001) and HTPR (HR 3.34, 95% CI 1.41–7.91, p = 0.006) was independently associated with recurrent ischemic events.

Discussion: In patients with minor stroke or TIA, the prevalence of HTPR was 22.7%, and HTPR was independently associated with recurrent ischemic events.     

Structural and functional alterations of the heart in Parkinson’s disease

Parkinson’s disease (PD) patients have most frequently heart failure. The cause of this increased prevalence is not known. We designed a study to assess the cardiac function and cardiac structure in patients with PD compared to a control group.

Methods: Cross-sectional study with 50 PD patients and 50 healthy matched controls. We performed electro and echocardiograms to all patients and controls. The measurements were blind. In addition, we performed a neurological assessment.

Results: PD patients had higher left ventricular mass index (114.2 ± 38.4 vs. 94.1 ± 26.4 g/m²; P = 0.003) and higher left atrial volume (30.1 ± 7.9 vs. 26.7 ± 6.2 ml/m²; P = 0.01). PD was an independent risk factor for elevated left ventricular filling pressures (OR = 2.7, CI 95% 2.2–6.3; P = 0.004). Concentric remodeling and left ventricular hypertrophy were associated with more advanced Hoehn and Yahr stages. Moreover, patients with more dysautonomia symptoms showed more left ventricular hypertrophy. Finally, PD group had longer QT interval than control group regardless of the drugs.

Conclusions: PD is significantly associated with increased concentric left ventricular hypertrophy and diastolic dysfunction. Advanced stages of PD are associated with a more severe cardiac affection. These findings can explain the increase of heart failure in PD patients. Cardiomyopathy could be a non-motor parkinsonian symptom.     

Atherosclerotic plaque burden of middle cerebral artery and extracranial carotid artery characterized by MRI in patients with acute ischemic stroke in China: association and clinical relevance

Objectives: This study sought to compare the atherosclerotic plaque burden between middle cerebral artery (MCA) and extracranial carotid artery (ECA) in ischemic stroke patients using high-resolution, black-blood (HR BB) MRI and to investigate the relationship between plaque burden found in both arteries and stroke severity.

Methods: All subjects with recent ischemic stroke underwent MCA and ECA HR BB MRI at 3.0 Tesla. For each artery segment, the thickness, area and signal intensities of plaques were recorded. Plaque burden, as measured by normalized wall index (NWI = wall area/total vessel area × 100%) were calculated. All patients received a clinical stroke severity score as measured by the National Institutes of Health Stroke Scale (NIHSS) scores at the time of admission.

Results: A total of 65 stroke subjects were included in the final analysis. MCA exhibited significantly greater NWI than the ipsilateral ECA (symptomatic MCA vs. ECA: 58.04 ± 8.19 vs. 37.53 ± 10.25, p < 0.001; asymptomatic MCA vs. ECA: 53.80 ± 4.49 vs. 34.85 ± 4.27, p < 0.001, respectively). NWI in symptomatic MCA and ECA were significantly associated with NIHSS scores (r = 0.779 vs. 0.645; p < 0.001 respectively). Moreover, stronger statistical correlations between NIHSS scores and NWI were found in MCA, as compared with ECA during multivariate linear regression analysis.

Conclusion: Greater atherosclerotic plaque burden and a closer association with stroke severity were found for the MCA as compared to the ipsilateral ECA. Identification of MCA plaque lesions by MRI may be helpful for developing more aggressive strategies for stroke prevention.     

Effect of whole body vibration on spasticity in hemiplegic legs of patients with stroke

Background: Several reports have focused on the effects of whole body vibration (WBV) on spasticity with differing results. Most studies used modified Ashworth scale (MAS) for qualitative measurements, but the effect was small.

Objective: To investigate the effect of WBV on spasticity in hemiplegic legs of patients with stroke using F-wave parameters.

Methods: Sixteen patients with stroke (mean age, 54.7 ± 13.5 years: time after stroke, 28.0 ± 26.3 months) were enrolled in a comparative before-and-after intervention trial. WBV was applied at 30 Hz (4–8 mm amplitude) for 5 min on the hamstrings, gastrocnemius, and soleus muscles in a sitting position. Spasticity was assessed according to the F-wave parameters, MAS, and active and passive range of motion (A-ROM and P-ROM, respectively). These assessments were obtained before, immediately after, and 20 min after each intervention.

Results: The F-wave parameters, MAS score, and P-ROM improved significantly after the WBV and remained below the baseline level, even after 20 min; no such change was noted in the unaffected limb via the F-wave parameters. The WBV also improved volitional movement immediately after intervention, as indicated by the A-ROM.

Conclusions: These results confirmed a significant reduction of motor neuron excitability until 20 min after the WBV, as indicated by F-wave parameters.     

Boosting the traditional physiotherapist approach for stroke spasticity using a sensorized ankle foot orthosis: a pilot study

Background: Spasticity is a motor disorder that is commonly treated manually by a physical therapist (PhT) stretching the muscles. Recent data on learning have demonstrated the importance of human-to-human interaction in improving rehabilitation: cooperative motor behavior engages specific areas of the motor system compared with execution of a task alone.

Objectives: We hypothesize that PhT-guided therapy that involves active collaboration with the patient (Pt) through shared biomechanical visual biofeedback (vBFB) positively impacts learning and performance by the Pt during ankle spasticity treatment. A sensorized ankle foot orthosis (AFO) was developed to provide online quantitative data of joint range of motion (ROM), angular velocity, and electromyographic activity to the PhT and Pt during the treatment of ankle spasticity.

Methods: Randomized controlled clinical trial. Ten subacute stroke inpatients, randomized into experimental (EXP) and control (CTRL) groups, underwent six weeks of daily treatment. The EXP group was treated with an active AFO, and the CTRL group was given an inactive AFO. Spasticity, ankle ROM, ankle active and passive joint speed, and coactivation index (CI) were assessed at enrollment and after 15–30 sessions.

Results: Spasticity and CI (p < 0.005) decreased significantly after training only in the EXP group, in association with a significant rise in active joint speed and active ROM (p < 0.05). Improvements in spasticity (p < 0.05), active joint speed (p < 0.001), and CI (p < 0.001) after treatment differed between the EXP and CTRL groups.

Conclusions: PhT–Pt sharing of exercise information, provided by joint sensorization and vBFB, improved the efficacy of the conventional approach for treating ankle spasticity in subacute stroke Pts.     

Neurological outcome and frequency of overdrainage in normal pressure hydrocephalus directly correlates with implanted ventriculo-peritoneal shunt valve type

Background: The correlation between neurological outcome and frequency of overdrainage in the management of idiopathic normal pressure hydrocephalus (iNPH) using different ventriculoperitoneal shunt valve types is under investigation. Thus, we retrospectively compared one group of iNPH patients implanted with a programmable differential pressure valve (DPV) with another group treated by implantation of a DPV in combination with a flow-regulated anti-siphon device valve (ASD).

Methods: A retrospective evaluation of clinical outcome and frequency of overdrainage of 40 consecutive iNPH patients following surgical management between 08/2010 and 08/2014 was performed. Within the first 2 years of the study, a programmable DPV was implanted in 21 patients (DPV-group, 14 males, 7 females, mean age 74.0 ± 6.0 years). In the following two years, a programmable DPV with a flow-regulated ASD was implanted in 19 patients (ASD- group, 12 males, 7 females, mean age 73.3 ± 4.2 years). Neurological outcome was assessed by employing the NPH recovery rate (comparison of pre- and postoperative Kiefer-score). Mean follow-up period was 12.4 ± 9.8 months.

Results: In the DPV-group, three patients (14.3%) experienced severe overdrainage needing surgical intervention despite initial higher valve opening pressures (175 ± 11 mmH₂O), compared to one non surgical overdrainage in the ASD-group despite significant lower valve opening pressure (144 ± 22 mmH₂O). Excellent/good clinical outcome was found in 78.9% of the patients implanted with ASD compared to 44.4% of patients in the DPV group (p < 0.05).

Conclusion: Our results clearly demonstrate reduction in surgical over-drainage frequency and resulting complications in iNPH patients, with significantly better clinical outcome following insertion of a flow regulated ASD VP shunt compared to a DPV VP shunt, despite both systems comprised a programmable opening pressure mechanism.     

Pilot randomized controlled trial to assess a physical therapy program on upper extremity function to counteract inactivity in chronic stroke

Background: In chronic stroke, feasible physical therapy (PT) programs are needed to promote function throughout life.

Objective: This randomized controlled pilot trial investigated the feasibility and effect of a PT program composed of strengthening exercises with elastic bands and bimanual functional training, with clearly defined doses based on the rate of perceived exertion (Borg scale), to counteract inactivity in chronic stroke.

Methods: Fifteen subjects > 6 month post-stroke were randomized to three-month of UE function training (UE group), or to lower extremity function training (LE group). At baseline (T0), post-intervention (T1) and three-month follow-up (T2) assessment included the Fugl-Meyer Assessment scale (FMA), Wolf Motor Function test (WMFT), grip strength, and muscle tone. Feasibility was also evaluated.

Results: The mixed-model ANOVAs revealed a significant interaction between the time and group factors for FMA (p < .001) and WMFT (p = .009). The UE group improved upper extremity function and motor recovery significantly more than the LE group. There was no significant interaction between treatment group and change in grip strength over time (p = .217). No between-group differences (p > .05) were found in muscle tone. In the UE group, the attendance rate was ≥85% for 71.4% of subjects and 85.7% showed high satisfaction. No adverse events were recorded. After treatment, adherence to the program was higher in the UE group.

Conclusions: The suggested PT program may be useful to improve the paretic UE function and motor recovery in chronic stroke. Moreover, it may be helpful to facilitate lifelong active involvement of stroke subjects in exercise.     

Comparison of the Mini-Balance Evaluations Systems Test with the Berg Balance Scale in relationship to walking speed and motor recovery post stroke*

Background: The Mini-BESTest is a recently developed balance assessment tool that incorporates challenging dynamic balance tasks. Few studies have compared the psychometric properties of the Mini-BESTest to the commonly used Berg Balance Scale (BBS). However, the utility of these scales in relationship to post stroke walking speeds has not been explored.

Objectives: The purpose of this study was to compare the sensitivity and specificity of the Mini-BESTest and BBS to evaluate walking speeds in individuals with stroke.

Design: A retrospective exploratory design.

Methods: Forty-one individuals with chronic stroke were evaluated with the Mini-BESTest, BBS, and 10-meter self-selected walk test (10MWT). Based on their self-selected gait speeds (below or above 0.8 m/s), participants were classified as slow and fast walkers.

Results: Significant linear correlations were observed between the Mini-BESTest vs. BBS (r = 0.72, p ≤ 0.001), Mini-BESTest vs. 10MWT (r = 0.58, p ≤ 0.001), and BBS vs. 10MWT (r = 0.30, p = 0.05). Independent t-tests comparing the balance scores for the slow and fast walkers revealed significant group differences for the Mini-BESTest (p = 0.003), but not for the BBS (p = 0.09). The Mini-BESTest demonstrated higher sensitivity (93%) and specificity (64%) compared to the BBS (sensitivity 81%, specificity 56%) for discriminating participants into slow and fast walkers.

Conclusions: The Mini-BESTest has a greater discriminative ability than the BBS to categorize individuals with stroke into slow and fast walkers.     

The improvement in respiratory function by inspiratory muscle training is due to structural muscle changes in patients with stroke: a randomized controlled pilot trial

Background: The changes effected by the inspiratory muscle training (IMT) on the structure of inspiratory muscles such as on the diaphragm, in patients with stroke, is unclear.

Objective: To investigate the effect of IMT on inspiratory function, diaphragm thickness, walking endurance, and fatigue in patients with stroke.

Methods: A total of 30 patients with stroke were randomized to either the experimental group or the control group. The experimental group (n = 15) underwent inspiratory muscle training with resistance adjusted to 30% of maximal inspiratory pressure, 90 breaths a day, 5 times a week for 6 weeks. Both groups received regular physical therapy for the same amount of time. The primary outcome measure was the diaphragm thickness ratio. The secondary outcomes were inspiratory function; maximal inspiratory pressure and inspiratory muscle endurance; and gait endurance and fatigue.

Results: There were significant differences between the two groups in the thickness ratio on the affected diaphragm thickness (medium effect size), maximal inspiratory pressure (medium effect size), and inspiratory muscle endurance (large effect size; Bonferroni correction p < 0.005). The gait endurance (medium effect size) and fatigue (small effect size) showed no significant differences in the between group comparison.

Conclusion: Inspiratory muscle training was effective in improving respiratory function and inducing structural changes, especially in the affected diaphragm.     

Investigation of subdural electrode displacement in invasive epilepsy surgery workup using neuronavigation and intraoperative MRI

Objectives: One of the main obstacles of electrode implantation in epilepsy surgery is the electrode shift between implantation and the day of explantation. We evaluated this possible electrode displacement using intraoperative MRI (iopMRI) data and CT/MRI reconstruction.

Methods: Thirteen patients (nine female, four male, median age 26 ± 9.4 years) suffering from drug-resistant epilepsy were examined. After implantation, the position of subdural electrodes was evaluated by 3.0 T-MRI and thin-slice CCT for 3D reconstruction. Localization of electrodes was performed with the volume-rendering technique. Post-implantation and pre-explantation 1.5 T-iopMRI scans were coregistered with the 3D reconstructions to determine the extent of electrode dislocation.

Results: Intraoperative MRI at the time of explantation revealed a relevant electrode shift in one patient (8%) of 10 mm. Median electrode displacement was 1.7 ± 2.6 mm with a coregistration error of 1.9 ± 0.7 mm. The median accuracy of the neuronavigation system was 2.2 ± 0.9 mm. Six of twelve patients undergoing resective surgery were seizure free (Engel class 1A, median follow-up 37.5 ± 11.8 months).

Conclusion: Comparison of pre-explantation and post-implantation iopMRI scans with CT/MRI data using the volume-rendering technique resulted in an accurate placement of electrodes. In one patient with a considerable electrode dislocation, the surgical approach and extent was changed due to the detected electrode shift.

Abbreviations: ECoG: electrocorticography; EZ: epileptogenic zone; iEEG: invasive EEG; iopMRI: intraoperative MRI; MEG: magnetoencephalography; PET: positron emission tomography; SPECT: single photon emission computed tomography; 3D: three-dimensional.     

Cognitive function and insulin resistance in elderly patients with type 2 diabetes

Purpose: To explore the relationship between cognitive impairment and insulin resistance (IR) in elderly patients with type-2 diabetes mellitus.

Materials and methods: Two hundred and twelve elderly patients with type-2 diabetes were enrolled in this study and assigned into either the cognitive impairment group (n = 100) or the normal cognitive group (n = 112). Gender, age, education, body mass index (BMI), total cholesterol, triglyceride, low-density lipoprotein cholesterol, creatinine (Cr), fasting plasma glucose, fasting insulin (FINS) and homeostasis model of assessment for IR index (HOMA-IR) were compared between the two groups. Multifactorial logistic regression analysis was performed.

Results: In cognitive impairment group, education level (33.00 vs 53.57%, p < 0.01) was lower, the level of BMI [(28.7 ± 4.5) kg/m² vs (23.9 ± 3.7) kg/m², p < 0.01], FINS [(21.8 ± 5.3) mU/L vs (12.9 ± 3.9) mU/L, p < 0.01], HOMA-IR [(6.9 ± 1.7) vs (3.9 ± 0.9), p < 0.01] were higher than the control group. In the logistic regression, education level (B = –0.996, p = 0.03), FINS (B = 1.120, p < 0.01) and HOMA-IR (B = 1.301, p < 0.01) were independent factors.

Conclusions: Our study demonstrates that the education level, FINS and HOMA-IR were independent factors of cognitive impairment in elderly patients with type-2 diabetes. IR is an important risk factor and higher education level in a protective factor for the cognitive impairment in elderly patients with type-2 diabetes.     

Prognosis of dolichoectasia in non-cardioembolic transient ischemic attack and minor stroke

Objectives This study aimed to estimate the prognosis of dolichoectasia in non-cardioembolic transient ischemic attack (TIA) and minor stroke patients.

Methods Data were derived from the imaging subgroup of patients in the Clopidogrel in High-risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE) trial. Dolichoectasia was defined as ectasia (basilar artery diameter >4.5 mm) and dolichosis (either basilar artery bifurcation above the suprasellar cistern or lateral to the margin of the clivus or dorsum sellae). The prognosis included ischemic stroke recurrence and poor functional outcome (modified Rankin scale 2–6) at 12-month follow-up. The association of dolichoectasia with risk factors and prognosis of patients were assessed using multivariable Cox regression models.

Results Overall, 1089 patients with magnetic resonance images in the CHANCE trial were included in this subanalysis. A total of 98 (9.0%) patients were detected with dolichoectasia, and 106 (9.7%) patients had a recurrent ischemic stroke at 12 months. Small artery occlusion (SAO) was more prevalent in patients with dolichoectasia compared with those without dolichoectasia (29.6% vs. 22.7%, hazard ratio [HR] 2.87, 95% confidence interval [CI] 1.59–5.17, p < 0.001). However, multivariate analysis showed no association of dolichoectasia with 12-month recurrent stroke (9.2% vs. 9.8%, HR, 1.15; 95%CI, 0.32–4.12; p = 0.83) and poor functional outcome (7.6% vs. 8.4%, odds ratio, 1.22; 95%CI, 0.24–6.08; p = 0.81) in the current subgroup analysis.

Conclusions Dolichoectasia was significantly associated with SAO. There was no relationship between dolichoectasia and 12-month prognosis of patients with non-cardioembolic TIA or minor stroke.