Restorative Neurology and Neuroscience - Volume 38, issue 2

Authors: Tatiyosyan, Sophia Anais | Rifai, Katharina | Wahl, Siegfried

Article Type: Research Article

Abstract: Background: In low vision patients, the assessment of contrast sensitivity is an essential tool to determine the stage of visual impairment. However, traditional contrast sensitivity tests rely on verbal feedback, and the expertise of the examiner. Objective: In the current study, a fast, OKN-based virtual diagnosis tool was developed estimating contrast sensitivity automatically without active cooperation of the patient as well as the practitioner within 3.5 minutes. Methods: In a HTC Vive headset with an SMI-eye tracker, a virtual rotating drum was implemented, and an algorithm was developed, evaluating the occurrence of an OKN. The tool …was evaluated in healthy subjects as well as under low vision simulation for two spatial frequencies and four contrasts. It was then compared to two contrast sensitivity estimates based on manual report on the orientation of static gratings as well as the movement direction of translating gratings. Results: An algorithm was developed, which matched ground truth ratings of occurrence of OKN with an accuracy of 88 %. Furthermore, known differences in contrast sensitivity between healthy and low vision conditions as well as a decrease in contrast sensitivity for lower spatial frequencies was successfully reproduced in the developed tool. Conclusions: The developed OKN-based sensitivity test represents a reliable proof of concept for technology readiness of virtual reality-based screening tools of visual function in practice, specifically in patients with difficulties to report perception verbally, or under conditions, where no experienced examiner is present. Show more

Keywords: Diagnostics, contrast sensitivity, eyetracking

DOI: 10.3233/RNN-190937

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 119-129, 2020

Authors: Zhang, Xiong | Tenerelli, Kevin | Wu, Suqian | Xia, Xin | Yokota, Satoshi | Sun, Catalina | Galvao, Joana | Venugopalan, Praseeda | Li, Chenyi | Madaan, Ankush | Goldberg, Jeffrey L. | Chang, Kun-Che

Article Type: Research Article

Abstract: Background: Glaucoma, the number one cause of irreversible blindness, is characterized by the loss of retinal ganglion cells (RGCs), which do not regenerate in humans or mammals after cell death. Cell transplantation provides an opportunity to restore vision in glaucoma, or other optic neuropathies. Since transplanting primary RGCs from deceased donor tissues may not be feasible, stem cell-derived RGCs could provide a plausible alternative source of donor cells for transplant. Objective: We define a robust chemically defined protocol to differentiate human embryonic stem cells (hESCs) into RGC-like neurons. Methods: Human embryonic stem cell lines (H7-A81 and …H9) and induced pluripotent stem cell (iPSC) were used for RGC differentiation. RGC immaturity was measured by calcium imaging against muscimol. Cell markers were detected by immunofluorescence staining and qRT-PCR. RGC-like cells were intravitreally injected to rat eye, and co-stained with RBPMS and human nuclei markers. All experiments were conducted at least three times independently. Data were analyzed by ANOVA with Tukey’s test with P value of <0.05 considered statistically significant. Results: We detected retinal progenitor markers Rx and Pax6 after 15 days of differentiation, and the expression of markers for RGC-specific differentiation (Brn3a and Brn3b), maturation (synaptophysin) and neurite growth (β-III-Tubulin) after an additional 15 days. We further examined the physiologic differentiation of these hESC-derived RGC-like progeny to those differentiated in vitro from primary rodent retinal progenitor cells (RPCs) with calcium imaging, and found that both populations demonstrate the immature RGC-like response to muscimol, a GABAA receptor agonist. By one week after transplant to the adult rat eye by intravitreal injection, the human RGC-like cells successfully migrated into the ganglion cell layer. Conclusions: Our protocol provides a novel, short, and cost-effective approach for RGC differentiation from hESCs, and may broaden the scope for cell replacement therapy in RGC-related optic neuropathies such as glaucoma. Show more

Keywords: Retinal ganglion cell, stem cell, cell transplant

DOI: 10.3233/RNN-190941

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 131-140, 2020

Authors: Shim, Jaehong | Hwang, Sujin | Ki, Kyongil | Woo, Youngkeun

Article Type: Research Article

Abstract: Background: EMG-triggered functional electrical stimulation (EMG-triggered FES) is one of the effective method for improving task performance and providing movement re-learning of central nervous system. Proprioceptive neuromuscular facilitation (PNF) is a traditional manual therapy that is used as a method to regain normal movement by providing specific training methods. Objective: The purpose of this study was to investigate the effect of EMG-triggered FES during trunk pattern in PNF on trunk control, balance, and gait of stroke patients. Methods: Forty participants were randomly allocated to EMG-triggered FES during PNF trunk pattern group (n  = 20) and PNF trunk …pattern group (n  = 20). This study was a pretest-posttest with a control group design for duration of 4weeks (30 min/5 times/1 week). Outcome measures involved trunk impairment scale (TIS), Berg balance scale (BBS), and dynamic gait index (DGI). Results: In the experimental group and control group, TIS, BBS, and DGI score was significantly increased after intervention. However, there was no significant difference between the two groups in the comparison of the experimental group and the control group according to the amount of change before and after the training. Conclusions: The results of this study showed that PNF trunk pattern affected the trunk control for stroke patients, and increased trunk control ability was effective in improving balance and walking. In addition, it was found that the EMG-triggered FES applied to the PNF trunk pattern affected the trunk control. Show more

Keywords: Balance, EMG-triggered functional electrical stimulation, proprioceptive neuromuscular facilitation, stroke, trunk

DOI: 10.3233/RNN-190944

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 141-150, 2020

Authors: Munari, Daniele | Fonte, Cristina | Varalta, Valentina | Battistuzzi, Elisa | Cassini, Silvia | Montagnoli, Anna Paola | Gandolfi, Marialuisa | Modenese, Angela | Filippetti, Mirko | Smania, Nicola | Picelli, Alessandro

Article Type: Research Article

Abstract: Background: Studies on robot-assisted gait training rehabilitation in multiple sclerosis have reported positive effects on mobility and quality of life. However, their effects on cognitive functions are difficult to determine because not all trials have included cognition assessments. Virtual reality-based training provides enhanced opportunity for stimulating cognitive abilities by repetitive practice, feedback information, and motivation for endurance practice. Objective: To compare the effects of innovative robot-assisted gait training combined with virtual reality versus standard robot-assisted gait training on information processing speed, sustained attention, working memory, and walking endurance in patients with multiple sclerosis. Methods: Seventeen outpatients …were randomly assigned to receive robot-assisted gait training either with or without virtual reality. The robot assisted gait training + virtual reality group underwent end-effector system training engendered by virtual reality. The standard training group underwent end-effector system training. A blinded rater evaluated patients before and after treatment and at one month follow-up. The outcome measures were the Paced Auditory Serial Addition Test, Phonemic Fluency Test, Novel Task, Digit Symbol, Multiple Sclerosis Quality of Life-54, 2-Minutes Walk Test, 10-Meter Walking Test, Berg Balance Scale, gait analysis, and stabilometric assessment. Results: Between-group comparisons showed a significant change on the 2-Minutes Walk Test (p = 0.023) after treatment in the robot-assisted gait training + virtual reality group. Significant improvement were obtained also in executive functions (p = 0.012). Both gains were maintained at the 1-month follow-up evaluation (p = 0.012, p = 0.012) in the robot-assisted gait training + virtual reality group. Both group improved quality of life after treatment (Multiple Sclerosis Quality of Life-54: Mental Health p = 0.018, Physical Health p = 0.017). Conclusions: Both training lead to positive influenced on executive functions. However larger positive effects on gait ability were noted after robot-assisted gait training engendered by virtual reality with multiple sclerosis. Robot-assisted gait training provides a therapeutic alternative and motivational of traditional motor rehabilitation. Show more

Keywords: Executive functions, quality of life, rehabilitation, robotics, walking

DOI: 10.3233/RNN-190974

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 151-164, 2020

Authors: Lee, Hye-Sun | Lim, Jae-Heon | Jeon, Byeong-Hyeon | Song, Chiang-Soon

Article Type: Research Article

Abstract: Background: Virtual reality (VR) training allows the creation of the most applicable practice environment incorporated into computer-generated multisensory imagery. Objectives: The purpose of this study was to investigate the effects of a virtual training program based on a RAPAEL smart glove on the upper extremity function and quality of life of community-dwelling individuals with chronic hemiparetic stroke. Methods: Thirty-six outpatients diagnosed as having a first stroke were selected to receive a therapeutic rehabilitation program at local rehabilitation units. Participants were allocated randomly into two groups: the non-immersive VR training (intervention) group and the recreational activity (control) …group. The intervention group received non-immersive VR training using a RAPAEL smart glove for 30 minutes per session, 3 days a week for 8 weeks. The control group performed recreational activities for the same period and also participated in a conventional rehabilitation program for 30 minutes per session, 3 days a week for 8 weeks as an additional therapy. To analyze the effects of the non-immersive VR intervention on upper extremity function, four clinical measures, namely the box and block test (BBT), the Wolf motor function test (WMFT), the Jebsen-Taylor hand function test (JTT), and a grip strength test, were used in this study. For the secondary clinical outcome, the trail-making test (TMT) was used to determine any improvement in cognitive function. Results: At week 8, upon completion of the non-immersive VR-training the intervention group demonstrated significantly greater WMFT scores (73.0±12.9 to 81.6±7.5), BBT scores (27.3±8.9 to 34.2±7.1), and grip strength (19.2±8.2 to 23.8±8.5) compared with WMFT scores (70.4±12.1 to 73.2±13.1), BBT scores (27.1±10.5 to 28.8±12.9), and grip strength (18.4±4.2 to 18.3±4.9) in the control group. Conclusions: This study suggests that virtual upper extremity training using the RAPAEL smart glove has reasonable and beneficial effects on upper extremity and cognitive function for chronic hemiparetic stroke survivors. Show more

Keywords: Stroke, Virtual reality, Upper extremity

DOI: 10.3233/RNN-190975

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 165-172, 2020

Authors: Byram, Susanna C. | Bialek, Samantha E. | Husak, Vicki A. | Balcarcel, Daniel | Park, James | Dang, Jacquelyn | Foecking, Eileen M.

Article Type: Research Article

Abstract: Background: Local anesthetic toxicity has been well-documented to cause neuronal injury, death, and dysfunction, particularly in a susceptible nerve. Objective: To determine whether select local anesthetics affect neuron survival and/or functional recovery of an injured nerve. Methods: This report describes 6 separate experiments that test immediate or delayed application of local anesthetics in 3 nerve injury models. Adult C57/black6 male mice underwent a facial nerve sham, transection, or crush injury. Local anesthetic or saline was applied to the facial nerve at the time of injury (immediate) or 1 day after injury (delayed). Average percent facial motoneuron …(FMN) survival was evaluated four-weeks after injury. Facial nerve regeneration was estimated by observing functional recovery of eye blink reflex and vibrissae movement after facial nerve crush injury. Results: FMN survival after: transection + immediate treatment with ropivacaine (54.8%), bupivacaine (63.2%), or tetracaine (66.9%) was lower than saline (85.5%) and liposomal bupivacaine (85.0%); crush + immediate treatment with bupivacaine (92.8%) was lower than saline (100.7%) and liposomal bupivacaine (99.3%); sham + delayed treatment with bupivacaine (89.9%) was lower than saline (96.6%) and lidocaine (99.5%); transection + delayed treatment with bupivacaine (67.3%) was lower than saline (78.4%) and liposomal bupivacaine (77.6%); crush + delayed treatment with bupivacaine (85.3%) was lower than saline (97.9%) and lidocaine (96.0%). The average post-operative time for mice to fully recover after: crush + immediate treatment with bupivacaine (12.83 days) was longer than saline (11.08 days) and lidocaine (10.92 days); crush + delayed treatment with bupivacaine (16.79 days) was longer than saline (12.73 days) and lidocaine (11.14 days). Conclusions: Our data demonstrate that some local anesthetics, but not all, exacerbate motoneuron death and delay functional recovery after a peripheral nerve injury. These and future results may lead to clinical strategies that decrease the risk of neural deficit following peripheral nerve blocks with local anesthetics. Show more

Keywords: Neurotoxicity, motoneuron survival, peripheral nerve block, local anesthetic toxicity, peripheral nerve injury, facial nerve injury, liposomal bupivacaine, regional anesthesia

DOI: 10.3233/RNN-190987

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 173-183, 2020

Authors: Digiacomo, Fabio | Tamburin, Stefano | Tebaldi, Stefano | Pezzani, Marco | Tagliafierro, Mario | Casale, Roberto | Bartolo, Michelangelo

Article Type: Correction

DOI: 10.3233/RNN-200001

Citation: Restorative Neurology and Neuroscience, vol. 38, no. 2, pp. 185-185, 2020