RESUMO
Background and Purpose: Diffusion weighted magnetic resonance imaging (DW-MRI) can be prognostic for response to neoadjuvant chemotherapy (nCRT) in patients with esophageal cancer. However, manual tumor delineation is labor intensive and subjective. Furthermore, noise in DW-MRI images will propagate into the corresponding apparent diffusion coefficient (ADC) signal. In this study a workflow is investigated that combines a denoising algorithm with semi-automatic segmentation for quantifying ADC changes. Materials and Methods: Twenty patients with esophageal cancer who underwent nCRT before esophagectomy were included. One baseline and five weekly DW-MRI scans were acquired for every patient during nCRT. A self-supervised learning denoising algorithm, Patch2Self, was used to denoise the DWI-MRI images. A semi-automatic delineation workflow (SADW) was next developed and compared with a manually adjusted workflow (MAW). The agreement between workflows was determined using the Dice coefficients and Brand Altman plots. The prognostic value of ADCmean increases (%/week) for pathologic complete response (pCR) was assessed using c-statistics. Results: The median Dice coefficient between the SADW and MAW was 0.64 (interquartile range 0.20). For the MAW, the c-statistic for predicting pCR was 0.80 (95% confidence interval (CI):0.56-1.00). The SADW showed a c-statistic of 0.84 (95%CI:0.63-1.00) after denoising. No statistically significant differences in c-statistics were observed between the workflows or after applying denoising. Conclusions: The SADW resulted in non-inferior prognostic value for pCR compared to the more laborious MAW, allowing broad scale applications. The effect of denoising on the prognostic value for pCR needs to be investigated in larger cohorts.
RESUMO
BACKGROUND: Effective and sustainable exercise training methods for improving balance poststroke are needed. OBJECTIVE: To evaluate the effect of Baduanjin Qigong for improving balance after stroke. METHODS: This was a single-blinded randomized controlled study in which only the assessor was blinded. Fifty-eight people with chronic stroke (mean age: 62.5 ± 11.8 years) were randomly assigned to the experimental (n = 29) or control group (n = 29). The experimental group underwent 8 weeks of supervised Baduanjin training (3 sessions per week). This was followed by home-based practice of the same exercises 3 days a week for another 8 weeks. The control group underwent 2 sessions of supervised conventional fitness training in the first week, followed by home-based exercise practice 3 days a week until the end of week 16. All outcomes were measured at baseline, week 8, and week 16. RESULTS: Significantly greater improvements in the Mini-Balance Evaluation Systems Test (Mini-BESTest), composite equilibrium score (Sensory Organization Test), 5 Times Sit to Stand, and Timed Up and Go test were detected at week 8 in the experimental group than in the control group (P < .017). Further improvement in the Mini-BESTest was observed from week 8 to 16 in the experimental group (P < .001). Other outcomes (Limit of Stability, Fall-Efficacy Scale, Modified Barthel Index, Stroke-Specific Quality of Life) showed no significant results. CONCLUSION: Baduanjin is effective in improving balance, leg strength, and mobility and is a safe and sustainable form of home-based exercise for people with chronic stroke.