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目的 探讨改良单图像法手工测量髌骨不稳患者胫骨结节-股骨滑车沟(tibial tuberosity-trochlear groove,TT-TG)间距的可行性。
方法 选取髌骨不稳患者30例。高年资手术医师A、B,使用改良单图像法手工测量髌骨不稳患者TT-TG间距,对比高资年影像学医师C,使用双图法测量髌骨不稳患者TT-TG间距。应用Cronbach′s alpha系数评价结果的可信度。应用组内相关系数(intraclass correlation coefficient,ICC)评价结果的可重复性。使用Bland-Altman分析图评价结果的一致性。
结果 高年资手术医师A、B使用改良单图像法手工测量髌骨不稳患者TT-TG间距分别和高年资影像学医师C使用双图法测量髌骨不稳患者TT-TG间距比较,Cronbach′s alpha系数分别为0.913和0.959,组内相关系数分别为0.913和0.958。Bland-Altman分析图显示,TT-TG间距差值(mm)的均值为-0.276(95%CI:-3.526~2.974)和0.143(95%CI:-3.110~3.397)。A、B医师之间使用改良单图像法手工测量髌骨不稳患者TT-TG间距比较,Cronbach′s alpha系数为0.891,组内相关系数为0.891。Bland-Altman分析图显示TT-TG间距差值(mm)的均值为-0.276(95%CI:-3.526~2.974)。
结论 改良单图像法手工测量髌骨不稳患者TT-TG间距操作简单,可以准确测量出髌骨不稳患者的TT-TG间距,该方法和双图法可以相互替换使用。 相似文献
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《The journal of sexual medicine》2020,17(1):48-59
IntroductionPremature ejaculation (PE) is a highly prevalent male sexual dysfunction. Previous studies have found abnormal activity in the sympathetic nervous system and penile sensory pathway of PE. Few studies have investigated the neural mechanisms underlying PE.AimThe aim of this study was to examine whether the altered cortico-subcortical network topological properties of the brain white matter structural network could be used to differentiate patients with PE from healthy control (HC) subjects.MethodsDiffusion tensor images data were collected from 32 patients with PE and 35 HC participants. Then, brain white matter structural networks were reconstructed from image acquisition.Main Outcome MeasureFurthermore, nodal measures were calculated and hub regions were identified using the graph-theoretical methods.ResultsFor cortical brain regions, increased strength, global efficiency, and decreased shortest path length were found in the right superior frontal gyrus (medial), and superior frontal gyrus (medial orbital) were found in patients with PE. In addition, patients with PE also showed decreased strength in the right rolandic operculum and decreased shortest path length, and increased global efficiency in the right inferior frontal gyrus (triangular part). For subcortical brain structures, patients with PE were associated with decreased shortest path length and increased global efficiency in the left insula and right caudate nucleus. Finally, the results showed that 9 PE-specific hub regions were identified in patients compared with HCs, including 7 cortical regions and 2 subcortical regions.Clinical ImplicationsOur results provide new understanding about the pathology of PE and enhances the understanding of PE pathology.Strength & LimitationsOur results offer biological markers for understanding the physiopathology of PE. However, our study is a cross-sectional design, longitudinal design studies need to explore the causal relationships between aberrant topological characteristics and PE.ConclusionOur results provide new insights into the neural mechanism of PE involving cortico-subcortical network changes, which could serve as a potential biomarker to differentiate individuals with PE from HCs.Chen J, Yang J, Huang X, et al. Variation in Brain Subcortical Network Topology Between Men With and Without PE: A Diffusion Tensor Imaging Study. J Sex Med 2020;17:48–59. 相似文献
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《Journal of the American College of Radiology》2020,17(4):504-510
ObjectiveDetermine radiologist ability to accurately select the probability of recommendation of additional imaging (RAI) for themselves and colleagues when arrayed in a feedback report.MethodsIn this institutional review board–approved study, we analyzed 318,366 diagnostic imaging reports from examinations performed in the radiology department of a large quaternary teaching hospital during calendar year 2016. A validated machine learning algorithm identified reports containing RAI. A multivariable logistic regression model was then used to determine the probability of RAI. In 2018, an e-mailed survey asked radiologists to identify their own RAI probability and that of their colleagues from a report arrayed lowest to highest. Radiologists were grouped into quartiles based on their RAI probability. χ2 Analysis compared self-assessment and assessment of colleagues between quartiles.ResultsForty-eight of 57 radiologists completed the survey (84.2%). Fourteen (29.2%) accurately self-identified their RAI probability (chose the correct quartile); 34 (70.8%) did not. There was no statistically significant difference between quartiles of radiologists and their ability to self-identify their RAI probability (ie, radiologists in the bottom or top quartile of RAI probabilities did not correctly predict their RAI probability). However, radiologists were better able to identify the RAI probability of their colleagues who were in the top and bottom quartiles.DiscussionRadiologists were unable to estimate their own RAI probability but were better at predicting the RAI probability of colleagues. Given that radiologists, and physicians in general, may be poor evaluators of their own performance, objective assessment tools are likely needed to help reduce unwarranted variation. 相似文献
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《Brain stimulation》2020,13(3):916-927
BackgroundDeep brain stimulation (DBS) is an effective treatment for movement disorders, yet its mechanisms of action remain unclear. One method used to study its circuit-wide neuromodulatory effects is functional magnetic resonance imaging (fMRI) which measures hemodynamics as a proxy of neural activity. To interpret functional imaging data, we must understand the relationship between neural and vascular responses, which has never been studied with the high frequencies used for DBS.ObjectiveTo measure neurovascular coupling in the rat motor cortex during thalamic DBS.MethodSimultaneous intrinsic optical imaging and extracellular electrophysiology was performed in the motor cortex of urethane-anesthetized rats during thalamic DBS at 7 different frequencies. We related Maximum Change in Reflectance (MCR) from the imaging data to Integrated Evoked Potential (IEP) and change in broadband power of multi-unit (MU) activity, computing Spearman’s correlation to determine the strength of these relationships. To determine the source of these effects, we studied the contributions of antidromic versus orthodromic activation in motor cortex perfusion using synaptic blockers.ResultsMCR, IEP and change in MU power increased linearly to 60 Hz and saturated at higher frequencies of stimulation. Blocking orthodromic transmission only reduced the DBS-induced change in optical signal by ∼25%, suggesting that activation of corticofugal fibers have a major contribution in thalamic-induced cortical activation.ConclusionDBS-evoked vascular response is related to both evoked field potentials as well as multi-unit activity. 相似文献
99.
《Foot and Ankle Surgery》2022,28(7):950-955
BackgroundLength change pattern of the ankle deltoid ligament during physiological ankle motion is still confused currently and had not been studied in vivo.MethodsThe deltoid ligaments from 7 cadaveric specimens were dissected. Lengths of each band during 30° plantarflexion to 20° dorsiflexion were measured. A dual fluoroscopy imaging system was utilized to capture the images of hindfoot joint of 7 healthy subjects during the stance phase of walking. 3D bone models were reconstructed from CT images. Lengths of each band were calculated after model-image registration utilizing a solid modeling software. Percentage of length variation and poses when the bands were in maximum extension were documented among each band.ResultsThe anterior border of tibiocalcaneal ligament (TCL) had only 1.7% length variation in vitro and 5.7% length variation in vivo. The tibionavicular ligament, tibiospring ligament, and deep anterior tibiotalar ligament were in maximum extension at 30° plantarflexion, however, superficial posterior tibiotalar ligament, deep posterior tibiotalar ligament, and the posterior border of TCL were in maximum extension at 20° dorsiflexion. The tibionavicular ligament, tibiospring ligament, and deep anterior tibiotalar ligament were in maximum extension during foot flat. The TCL was in maximum extension during midstance. The superficial posterior tibiotalar ligament and deep posterior tibiotalar ligament were in maximum extension during heel off and toe off.ConclusionThe length of TCL did not change during ankle dorsiflexion and plantarflexion. The bands anterior to and posterior to the TCL showed different length change pattern during physiological ankle dorsiflexion and plantarflexion. 相似文献
100.