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1.
Front Bioeng Biotechnol ; 12: 1360560, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511128

RESUMO

Introduction: This study employed surgical robot to perform anatomic single-bundle reconstruction using the modified transtibial (TT) technique and anteromedial (AM) portal technique. The purpose was to directly compare tunnel and graft characteristics of the two techniques. Methods: Eight cadaveric knees without ligament injury were used in the study. The modified TT and AM portal technique were both conducted under surgical robotic system. Postoperative data acquisition of the tunnel and graft characteristics included tibial tunnel position, tunnel angle, tunnel length and femoral tunnel-graft angle. Results: The mean tibial tunnel length of the modified TT technique was significantly shorter than in the AM portal technique (p < 0.001). The mean length of the femoral tunnel was significantly longer for the modified TT technique than for the AM portal technique (p < 0.001). The mean coronal angle of the tibial tunnel was significantly lower for the modified TT technique than for the AM portal technique (p < 0.001). The mean coronal angle of the femoral tunnel was significantly lower for the AM portal technique than for the modified TT technique (p < 0.001). The AM portal technique resulted in a graft bending angle that was significantly more angulated in the coronal (p < 0.001) and the sagittal planes (p < 0.001) compared with the modified TT technique. Discussion: Comparison of the preoperative planning and postoperative femoral tunnel positions showed that the mean difference of the tunnel position was 1.8 ± 0.4 mm. It suggested that the surgical navigation robot could make predictable tunnel position with high accuracy. The findings may support that the modified TT technique has benefits on femoral tunnel length and obliquity compared with AM portal technique. The modified TT technique showed a larger femoral tunnel angle in the coronal plane than the AM portal technique. Compared with the modified TT technique, the more horizontal trajectory of the femoral tunnel in the AM portal technique creates a shorter femoral tunnel length and a more acute graft bending angle.

2.
Front Neurol ; 14: 1090808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006479

RESUMO

Background: Constraint-induced movement therapy (CIMT) targeting the lower limb function uses various methods. The influence of CIMT methods on lower limb outcomes after stroke has rarely been examined. Objectives: This study aimed to examine CIMT effects on lower limb outcomes and explore the influence of CIMT methods on treatment effects after stroke, with other potential factors considered as covariates. Methods: PubMed, Web of Science, Cochrane Library, Academic Search Premier via EBSCOHost, and PEDro databases were searched until September 2022. We included randomized control trials with CIMT targeting the lower limb function and dosage-matched active control. The Cochrane risk-of-bias tool was used to evaluate the methodological quality of each study. Hedges' g was used to quantify the effect size of CIMT on outcomes compared to the active control. Meta-analyses were conducted across all studies. A mixed-variable meta-regression analysis was used to investigate the influence of CIMT methods on treatment effects after stroke, with other potential factors considered as covariates. Results: Twelve eligible randomized controlled trials with CIMT were included in the meta-analysis, where 10 trials were with a low risk of bias. A total of 341 participants with stroke were involved. For the treatment effects on the lower limb function, CIMT showed a moderate short-term effect size [Hedges' g = 0.567; P > 0.05; 95% confidence interval (CI): 0.203-0.931], but a small and insignificant long-term effect size (Hedges' g = 0.470; P > 0.05; 95%CI: -0.173 to 1.112), compared with conventional treatment. The CIMT method of using a weight strapped around the non-paretic leg and the ICF outcome category of the movement function were identified as significant factors contributing to the heterogeneity of short-term effect sizes across studies (ß = -0.854 and 1.064, respectively, R 2 = 98%, P > 0.05). Additionally, using a weight strapped around the non-paretic leg had a significant contribution to the heterogeneity of long-term effect sizes across studies as well (ß = -1.000, R 2 = 77%, P > 0.05). Conclusion: Constraint-induced movement therapy is superior to conventional treatment for improvement of lower limb function in the short-term but not in the long-term. The CIMT method of using a weight strapped around a non-paretic leg contributed negatively to the treatment effect, and therefore might not be recommended. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, identifier: CRD42021268681.

3.
Front Aging Neurosci ; 15: 1068943, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36967824

RESUMO

Background: Freezing of gait (FoG) is a severely disabling symptom in Parkinson's disease (PD). The cortical mechanisms underlying FoG during locomotion tasks have rarely been investigated. Objectives: We aimed to compare the cerebral haemodynamic response during FoG-prone locomotion tasks in patients with PD and FoG (PD-FoG), patients with PD but without FoG (PD-nFoG), and healthy controls (HCs). Methods: Twelve PD-FoG patients, 10 PD-nFoG patients, and 12 HCs were included in the study. Locomotion tasks included normal stepping, normal turning and fast turning ranked as three difficulty levels based on kinematic requirements and probability of provoking FoG. During each task, we used functional near-infrared spectroscopy to capture concentration changes of oxygenated haemoglobin (ΔHBO2) and deoxygenated haemoglobin (ΔHHB) that reflected cortical activation, and recorded task performance time. The cortical regions of interest (ROIs) were prefrontal cortex (PFC), supplementary motor area (SMA), premotor cortex (PMC), and sensorimotor cortex (SMC). Intra-cortical functional connectivity during each task was estimated based on correlation of ΔHBO2 between ROIs. Two-way multivariate ANOVA with task performance time as a covariate was conducted to investigate task and group effects on cerebral haemodynamic responses of ROIs. Z statistics of z-scored connectivity between ROIs were used to determine task and group effects on functional connectivity. Results: PD-FoG patients spent a nearly significant longer time completing locomotion tasks than PD-nFoG patients. Compared with PD-nFoG patients, they showed weaker activation (less ΔHBO2) in the PFC and PMC. Compared with HCs, they had comparable ΔHBO2 in all ROIs but more negative ΔHHB in the SMC, whereas PD-nFoG showed SMA and PMC hyperactivity but more negative ΔHHB in the SMC. With increased task difficulty, ΔHBO2 increased in each ROI except in the PFC. Regarding functional connectivity during normal stepping, PD-FoG patients showed positive and strong PFC-PMC connectivity, in contrast to the negative PFC-PMC connectivity observed in HCs. They also had greater PFC-SMC connectivity than the other groups. However, they exhibited decreased SMA-SMC connectivity when task difficulty increased and had lower SMA-PMC connectivity than HCs during fast turning. Conclusion: Insufficient compensatory cortical activation and depletion of functional connectivity during complex locomotion in PD-FoG patients could be potential mechanisms underlying FoG. Clinical trial registration: Chinese clinical trial registry (URL: http://www.chictr.org.cn, registration number: ChiCTR2100042813).

4.
J Clin Med ; 11(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36143105

RESUMO

Specific knee kinematic alterations have been theorized to correlate with the progression of cartilage degeneration, and therefore, post-traumatic osteoarthritis in patients with anterior cruciate ligament reconstruction (ACLR). However, how specific knee kinematic alterations contribute to knee joint cartilage degenerations remains to be unclear. To solve this problem, we hypothesized that there are specific cartilage-degenerating kinematic gait patterns that could be supported by the specific areas of cartilage lesions in ACLR knees. Thirty patients with unilateral ACLR knees and 30 healthy controls were recruited for the study. The kinematic differences between the ACLR knees and the healthy control knees during the stance phase were calculated to identify the kinematic patterns. Cartilage lesion distribution characteristics were acquired for patients with ACLR knees to validate the kinematic patterns using magnetic resonance images. Two kinematic patterns were modeled, i.e., sagittal (increased flexion angle and posterior tibial translation) and coronal (increased lateral tibial translation and abduction angle) kinematic patterns. For the sagittal pattern, the cartilage lesion distributions showed that there were more cartilage lesions (CLs) in the superoposterior regions than the posterior regions in the femoral condyles (p = 0.001), and more CLs in the posterior regions than the middle regions in the tibial plateau (p < 0.001). For the coronal pattern, the cartilage lesion distributions showed that there were more CLs in the lateral compartments near the tibial spine than the medial compartments near the tibial spine (tibial sides, p = 0.005 and femoral sides, p = 0.290). To conclude, the cartilage degeneration distribution evidence largely supports that the two kinematic patterns may contribute to cartilage degeneration in ACLR knees. These findings may provide a potential strategy of delaying early cartilage degeneration in ACLR knees by using motion (kinematic) pattern modification or training. However, investigations should be conducted on the actual effects of this potential strategy.

5.
Gait Posture ; 97: 8-12, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35843009

RESUMO

BACKGROUND: Accurate measurements of in-vivo knee joint kinematics are essential to elucidate healthy knee motion and the changes that accompany injury and repair. Although numerous experimental measurements have been reported, the accurate non-invasive analysis of in-vivo knee kinematics remains a challenge in biomechanics. RESEARCH QUESTION: The study objective was to investigate in-vivo knee kinematics before, at, and after contact during walking and running using a combined high-speed dual fluoroscopic imaging system (DFIS) and magnetic resonance (MR) imaging technique. METHODS: Three-dimensional (3D) knee models of ten participants were created using MR images. Knee kinematics during walking and running were determined using high-speed DFIS. The 3D knee models were then related to fluoroscopic images to obtain in-vivo six-degrees-of-freedom knee kinematics. RESULTS: Before contact knee flexion, external femoral rotation, and proximal-distal distance were 11.9°, 3.4°, and 1.0 mm greater during running compared to walking, respectively. Similar differences were observed at initial contact (9.9°, 7.9°, and 0.9 mm, respectively) and after contact (6.4°, 2.2°, and 0.8 mm, respectively). Posterior femoral translation at initial contact was also increased during running compared to walking. SIGNIFICANCE: This study demonstrated accurate instantaneous in-vivo knee kinematic characteristics that may further the understanding of the intrinsic biomechanics of the knee during gait.


Assuntos
Articulação do Joelho , Corrida , Fenômenos Biomecânicos , Humanos , Joelho , Amplitude de Movimento Articular , Caminhada
6.
Sci Rep ; 11(1): 24266, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930931

RESUMO

To validate the accuracy of Cone beam computed tomography (CBCT) cervical spine modeling with three dimensional (3D)-3D registration for in vivo measurements of cervical spine kinematics. CBCT model accuracy was validated by superimposition with computed tomography (CT) models in 10 healthy young adults, and then cervical vertebrae were registered in six end positions of functional movements, versus a neutral position, in 5 healthy young adults. Registration errors and six degrees of freedom (6-DOF) kinematics were calculated and reported. Relative to CT models, mean deviations of the CBCT models were < 0.6 mm. Mean registration errors between end positions and the reference neutral position were < 0.7 mm. During flexion-extension (F-E), the translation in the three directions was small, mostly < 1 mm, with coupled LB and AR both < 1°. During lateral bending (LB), the bending was distributed roughly evenly, with coupled axial rotation (AR) opposite to the LB at C1-C2, and minimal coupled F-E. During AR, most of the rotation occurred in the C1-C2 segment (29.93 ± 7.19° in left twist and 31.38 ± 8.49° in right twist) and coupled LB was observed in the direction opposite to that of the AR. Model matching demonstrated submillimeter accuracy in cervical spine kinematics data. The presently evaluated low-radiation-dose CBCT technique can be used to measure 3D spine kinematics in vivo across functional F-E, AR, and LB positions, which has been especially challenging for the upper cervical spine.


Assuntos
Fenômenos Biomecânicos , Vértebras Cervicais/fisiologia , Movimento , Rotação , Adulto , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pescoço , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
7.
Sensors (Basel) ; 21(2)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435444

RESUMO

With the rapid development of artificial intelligence and fifth-generation mobile network technologies, automatic instrument reading has become an increasingly important topic for intelligent sensors in smart cities. We propose a full pipeline to automatically read watermeters based on a single image, using deep learning methods to provide new technical support for an intelligent water meter reading. To handle the various challenging environments where watermeters reside, our pipeline disentangled the task into individual subtasks based on the structures of typical watermeters. These subtasks include component localization, orientation alignment, spatial layout guidance reading, and regression-based pointer reading. The devised algorithms for orientation alignment and spatial layout guidance are tailored to improve the robustness of our neural network. We also collect images of watermeters in real scenes and build a dataset for training and evaluation. Experimental results demonstrate the effectiveness of the proposed method even under challenging environments with varying lighting, occlusions, and different orientations. Thanks to the lightweight algorithms adopted in our pipeline, the system can be easily deployed and fully automated.

8.
Neurology ; 95(10): e1392-e1403, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32631922

RESUMO

OBJECTIVE: To develop and validate a nomogram to predict epilepsy in patients with radiation-induced brain necrosis (RN). METHODS: The nomogram was based on a retrospective analysis of 302 patients who were diagnosed with symptomatic RN from January 2005 to January 2016 in Sun Yat-sen Memorial Hospital using the Cox proportional hazards model. Discrimination of the nomogram was assessed by the concordance index (C index) and the calibration curve. The results were internally validated using bootstrap resampling and externally validated using 128 patients with RN from 2 additional hospitals. RESULTS: A total of 302 patients with RN with a median follow-up of 3.43 years (interquartile range 2.54-5.45) were included in the training cohort; 65 (21.5%) developed symptomatic epilepsy during follow-up. Seven variables remained significant predictors of epilepsy after multivariable analyses: MRI lesion volume, creatine phosphokinase, the maximum radiation dose to the temporal lobe, RN treatment, history of hypertension and/or diabetes, sex, and total cholesterol level. In the validation cohort, 28 out of 128 (21.9%) patients had epilepsy after RN within a median follow-up of 3.2 years. The nomogram showed comparable discrimination between the training and validation cohort (corrected C index 0.76 [training] vs 0.72 [95% confidence interval 0.62-0.81; validation]). CONCLUSION: Our study developed an easily applied nomogram for the prediction of RN-related epilepsy in a large RN cohort. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that a nomogram predicts post-RN epilepsy.


Assuntos
Irradiação Craniana/efeitos adversos , Epilepsia/diagnóstico , Epilepsia/etiologia , Nomogramas , Lesões por Radiação/complicações , Encéfalo/patologia , Encéfalo/efeitos da radiação , Feminino , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/etiologia , Necrose/patologia , Lesões por Radiação/diagnóstico , Lesões por Radiação/patologia , Estudos Retrospectivos , Fatores de Risco
9.
Brain Behav ; 10(3): e01554, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32017458

RESUMO

INTRODUCTION: The apolipoprotein B/apolipoprotein A1 (ApoB/ApoA1) ratio is recognized as a clinical indicator of cardiovascular disease and ischemic cerebral disease. Cerebrovascular dysfunction is also involved in head and neck radiotherapy. The aim of this study was to investigate the correlation between ApoB/ApoA1 ratio and the severity of radiation-induced brain necrosis (RN) in patients who underwent radiotherapy after nasopharyngeal carcinoma (NPC). METHODS: In this retrospective study, 191 NPC patients diagnosed with RN were evaluated. Clinical characteristics, serum lipid, apolipoproteins, and brain magnetic resonance imaging findings were collected. Serum lipid and apolipoproteins were quantified using standard diagnostic assays, and the quality of life (QOL) was assessed by the World Health Organization quality of life abbreviated instrument (WHOQOL-BREF). RESULTS: ApoB/ApoA1 ratio was positively correlated with lesion volume (r = .18, p = .03) and negatively correlated with WHOQOL-BREF scores (r = -.28, p < .01). The ApoB/ApoA1 ratio and intensity-modulated radiation therapy (IMRT) were independent risk factor of RN volume. Moreover, ApoB/ApoA1 ratio was significantly negatively correlated with physical health (r = -.29, p < .01), psychological (r = -.27, p < .01), social relationships (r = -.17, p = .02), and environment (r = -.27, p < .01) domains of WHOQOL-BREF. CONCLUSIONS: Serum ApoB/ApoA1 ratio is positively correlated with RN volume, which indicated serum ApoB/ApoA1 ratio as an independent risk factor for lesion volume in patients with RN after radiotherapy for NPC, suggesting a bright intervention target in RN treatment.


Assuntos
Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Encéfalo/patologia , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Qualidade de Vida , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/sangue , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/radioterapia , Necrose/patologia , Estudos Retrospectivos , Fatores de Risco
10.
Radiother Oncol ; 137: 16-23, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31048233

RESUMO

BACKGROUND: Radiotherapy is the standard radical treatment for nasopharyngeal carcinoma (NPC) and may cause radiation-induced brain necrosis (RN). Intravenous steroids have been considered as an effective treatment for RN. However, evidence concerning the efficacy of different doses of intravenous steroid therapy remains insufficient to establish the optimal regimen for NPC patients with RN. METHODS: We retrospectively reviewed charts of 169 patients who were diagnosed with RN after radiotherapy for NPC, treated with low-dose or high-dose intravenous methylprednisolone (IVMP) and followed up for 12 months. We collected the clinical data, including the Late Effects of Normal Tissue (LENT)/Subjective, Objective, Management, Analytic (SOMA) scales score and Montreal Cognitive Assessment (MoCA) score. Magnetic resonance imaging (MRI) was performed pre- and post-treatment to define the radiographic response. RESULTS: There were no significant differences in the treatment response based on MRI, or changes in clinical symptoms and cognitive function between low and high-dose groups. Thirty of 93 low-dose patients (32.3%) and 21 of 76 high-dose patients (27.6%) presented effective response in MRI, with no significant differences between groups (P = 0.515). Neither group showed a significant difference in the effective rate based on the MoCA total score and LENT/SOMA score. The most commonly reported grade 3 adverse events in the high-dose group (n = 76) were infections and infestations (3 [3.9%] vs. none for low-dose group). CONCLUSIONS: We found low-dose IVMP was not inferior to high-dose IVMP for NPC patients with RN. In addition, treatment-related infections and infestations were likewise more common with high-dose steroid than low-dose steroid.


Assuntos
Encéfalo/efeitos da radiação , Metilprednisolona/administração & dosagem , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/tratamento farmacológico , Adulto , Idoso , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/patologia , Necrose , Estudos Retrospectivos
11.
Support Care Cancer ; 27(11): 4213-4219, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30834973

RESUMO

Radiation-induced optic neuropathy (RION) is a severe visual complication resulting from radiotherapy of the head and neck, which mostly occurs in patients with nasopharyngeal carcinoma (NPC) in the southern part of China. The mechanism of RION is unclear. Therefore, identifying risk factors for RION is an important step towards enhancing our understanding. In the current study, we retrospectively reviewed patients with NPC who were admitted to Sun Yat-Sen Memorial Hospital for visual loss between 2006 and 2017. The study included 38 participants (68 eyes) in the corticosteroid-effective group and 35 participants (64 eyes) in the corticosteroids-ineffective group. We analyzed potential risk factors for RION and developed a prediction model for the therapeutic effect of corticosteroid effect based on a random forests method. The prediction model showed a high accuracy with an area under the receiver operating characteristic curve of 0.932 (95% confidence interval = 0.889-0.975). Our results revealed that blood urea nitrogen (BUN) was significantly associated with RION and that RION patients with higher BUN levels responded better to corticosteroid treatment. Altogether, these results suggest that a prediction model, based on clinical factors, could be applied to estimate the therapeutic effect of corticosteroids on RION. Further investigation, however, is needed to confirm the study conclusion.


Assuntos
Corticosteroides/uso terapêutico , Carcinoma Nasofaríngeo/radioterapia , Doenças do Nervo Óptico/tratamento farmacológico , Nervo Óptico/efeitos da radiação , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Lesões por Radiação/tratamento farmacológico , Adulto , Nitrogênio da Ureia Sanguínea , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
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