ABSTRACT
In optical tomography, it is challenging to obtain high-quality results for complex-structured objects which induce multiple scattering. Nonlinear reconstruction methods outperform linear ones in these situations. A promising nonlinear method is the approach based on beam propagation method, but its accuracy may decrease for complicated structures. In this paper, we describe a novel tomographic reconstruction method using multi-slice wave propagation method (WPM) as the forward model, which simulates the scattering process more precisely but has not been introduced in tomographic reconstruction before. The computational model of WPM is presented. To tackle the computational complexity, we propose an efficient scheme to compute the transmitted field and its derivative. We then use an iterative optimization method to recover the quantitative refraction index distribution. We also discuss the influences of the parameters in the method and how to determine their values. The experimental results demonstrate that this method can address multiple scattering problems and provide high accuracy for complex-structured objects.
ABSTRACT
OBJECTIVES: To evaluate the effectiveness of repetitive transcranial magnetic stimulation (rTMS) and sensory cueing (SC) for improving hemi-spatial attention deficits related to unilateral neglect, upper limb function and independence of stroke patients. METHODS: An assessor-blinded randomized controlled trial (RCT) was conducted. Eligible stroke patients were treated with rTMS (n =17) or rTMS combined with SC (n =16) in addition to conventional rehabilitation measures. rTMS was applied with low frequency (1 Hz) over the posterior parietal cortex (P5) of the lefthemisphere, 90% resting motor threshold, 900 pulses each session, one session per day, and 5 d per week for 2 weeks. SC was emitted using a wristwatch device attached to the hemiplegic arm for 2 weeks with a cumulative wear time of 3 h per day. The severity of unilateral neglect [behavioral inattention test conventional subtests (BITC), Catherine Bergego scale (CBS)], activity of daily living [modified Barthel index (MBI)], and upper limb function [Fugl-Meyer assessment (FMA), action research arm test (ARAT)] of the patients were measured pre- and post-interventions (immediately after 2 weeks' treatment) by an occupational therapist. RESULTS: BIT-C was relieved significantly over time in both groups. But rTMS+SC had greater improvement than rTMS alone (P <0.05). No significant differences was found between the two groups in other outcomes (CBS, FMA, ARAT). CONCLUSION: rTMS combined with SC is better than rTMS alone for treating unilateral neglect in stroke patients.
Subject(s)
Stroke Rehabilitation , Stroke/therapy , Transcranial Magnetic Stimulation , Humans , Parietal Lobe , Treatment OutcomeABSTRACT
INTRODUCTION: Vascular cognitive impairment (VCI) has an increasing prevalence worldwide, accounting for at least 20%-40% of all diagnoses of dementia. The decline in cognitive function seriously impairs patients' activities of daily living and social participation and reduces their quality of life. However, there is still a lack of advanced, definitive rehabilitation programmes for VCI. Hyperbaric oxygen therapy (HBOT) and repetitive transcranial magnetic stimulation (rTMS) are recognised treatments for improving cognitive impairment. The former can restore oxygen supply in the brain by increasing oxygen partial pressure in brain tissue, while the latter can enhance neuronal excitability and promote synaptic plasticity. However, no studies have explored the effect of HBO combined with rTMS on VCI. METHODS AND ANALYSIS: This study is designed as a single-centre, assessor-blind, randomised controlled clinical trial with four parallel arms. A total of 72 participants will be recruited and randomly assigned to the control group, HBOT group, rTMS group and HBOT combined with rTMS group at a ratio of 1:1:1:1. All enrolled participants will receive conventional treatment. The entire intervention period is 4 weeks, with a 3-week follow-up. Outcomes will be measured at baseline (T0), after a 4-week intervention (T1) and after an additional 3-week follow-up period (T2). The primary endpoint is the Montreal Cognitive Assessment score. The secondary endpoints are Mini-Mental State Examination score, Modified Barthel Index score, latency and amplitude of P300, cerebral cortical oxygenated haemoglobin (HbO2) and deoxygenated haemoglobin (HbR) concentrations as measured by task-state functional near-infrared spectroscopy. ETHICS AND DISSEMINATION: Ethics approval was obtained from the West China Hospital Clinical Trials and Biomedical Ethics Committee of Sichuan University (ethics reference: 2022 (1972)). The findings will be published in peer-reviewed journals and disseminated through scientific conferences and seminars. TRIAL REGISTRATION NUMBER: ChiCTR2300068242.
Subject(s)
Cognitive Dysfunction , Hyperbaric Oxygenation , Humans , Transcranial Magnetic Stimulation , Activities of Daily Living , Quality of Life , Cognitive Dysfunction/rehabilitation , Hemoglobins , Oxygen , Randomized Controlled Trials as TopicABSTRACT
OBJECTIVE: To systematically evaluate the diagnostic accuracy of monofilament tests for detecting diabetic peripheral neuropathy. METHODS: We searched EMBASE (OvidSP), MEDLINE (OvidSP), the Cochrane Library, and Web of Science to identify diagnostic accuracy trials of monofilament tests for detecting diabetic peripheral neuropathy. We used a hierarchical summary receiver operating characteristics (HSROC) model to conduct the meta-analysis of diagnostic accuracy of monofilament tests for detecting diabetic peripheral neuropathy. RESULTS: A total of 19 comparative trials met the inclusion criteria and were part of the qualitative synthesis. Eight trials using nerve conduction studies as the reference standard were selected for the meta-analysis. The pooled sensitivity and specificity of monofilament tests for detecting diabetic peripheral neuropathy were 0.53 (95% confidence interval (CI) 0.32 to 0.74) and 0.88 (95% CI 0.78 to 0.94), respectively. The pooled positive likelihood ratio and negative likelihood ratio were 4.56 (95% CI 2.93 to 7.10) and 0.53 (95% CI 0.35 to 0.81), respectively. CONCLUSIONS: Our review indicated that monofilament tests had limited sensitivity for screening diabetic peripheral neuropathy. The clinical use of the monofilament test in the evaluation of diabetic peripheral neuropathy cannot be encouraged based on currently available evidence.