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31.
《Journal of vascular and interventional radiology : JVIR》2020,31(4):635-643
PurposeThis study evaluated the factors affecting contralateral and ipsilateral recurrent deep vein thrombosis (DVT) after iliac vein stent placement in patients with iliac vein compression syndrome (IVCS).Materials and MethodsData from 130 patients (95 female patients) who underwent catheter-directed thrombolysis and stent placement for IVCS with left lower leg thrombosis at a single institution were retrospectively analyzed. Mean patient age was 69.0 ± 14.0 years old. Median follow-up was 14 months (range, 3–164 months). Anticoagulation therapy was prescribed for 6 months, followed by lifelong antiplatelet therapy. Multivariate logistic regression analysis was performed to evaluate the factors affecting the development of contralateral and ipsilateral recurrent DVT.ResultsSeven patients (5.4%) developed contralateral DVT (median, 26 months; range, 2–61 months), and 11 patients (8.5%) developed ipsilateral DVT (median, 1 month; range, 0–53 months). Stent location (odds ratio [OR], 11.564; 95% confidence interval [CI], 1.159–115.417) and in-stent thrombosis during follow-up (OR, 15.142; 95% CI, 1.406–163.119) were predictors of recurrent contralateral DVT. Thrombophilia (OR, 47.560; 95% CI, 2.369–954.711), remaining inferior vena cava filter (OR, 30.552; 95% CI, 3.495–267.122), and in-stent thrombosis during follow-up (OR, 82.057; 95% CI, 2.915–2309.848) were predictors of ipsilateral DVT.ConclusionsContralateral DVT occurs late and is associated with extension of the iliac vein stent to the inferior vena cava and in-stent thrombosis. Ipsilateral DVT occurs relatively early and is associated with thrombophilia, remaining inferior vena cava filter, and in-stent thrombosis. 相似文献
32.
《Brain stimulation》2020,13(2):499-506
BackgroundCurrent implementations of direct brain stimulation for epilepsy in patients involve high-frequency (HFS) electrical current and targeting of grey matter. Studies have shown that low-frequency (LFS) fiber-tract stimulation may also prove effective. To compare the efficacy of high-frequency grey matter stimulation to the low-frequency fiber tract stimulation technique a well-controlled set of experiments using a single animal model of epilepsy is needed.ObjectiveThe goal of this study was to determine the relative efficacy of different direct brain stimulation techniques for suppressing seizures using an acute rat model of focal cortical seizures.Methods4-AP was injected into the S1 region of cortex in rodents over 3 h. LFPs were recorded from the seizure focus and mirror focus to monitor seizure frequency during the experiments. CC-LFS, HFS-ANT, Focal-HFS, or a transection of the CC was applied.ResultsStimulation of the CC yielded a 65% ±14% (p = 0.0014) reduction of seizures in the focus and a 97% ±15% (p = 0.0026) reduction in the mirror focus (n = 7). By comparison transection of the CC produced a 65% ±18% reduction in the focus and a non-statistically significant reduction of 57% ±18% (p = 0.1381) in the mirror focus (n = 5). All other methods of stimulation failed to have a statistically significant effect on seizure suppression.ConclusionsLFS of the CC is the only method of stimulation to significantly reduce seizure frequency in this model of focal cortical seizures. These results support the hypothesis that LFSof fiber tracts has significant potential for seizure control. 相似文献
33.
Measuring conduction velocity distributions in peripheral nerves using neurophysiological techniques
《Clinical neurophysiology》2020,131(7):1581-1588
ObjectiveTo determine how long it takes for neural impulses to travel along peripheral nerve fibers in living humans.MethodsA collision test was performed to measure the conduction velocity distribution of the ulnar nerve. Two stimuli at the distal and proximal sites were used to produce the collision. Compound muscle or nerve action potentials were recorded to perform the measurements on the motor or mixed nerve, respectively. Interstimulus interval was set at 1–5 ms. A quadri-pulse technique was used to measure the refractory period and calibrate the conduction time.ResultsCompound muscle action potential produced by the proximal stimulation started to emerge at the interstimulus interval of about 1.5 ms and increased with the increment in interstimulus interval. Two groups of motor nerve fibers with different conduction velocities were identified. The mixed nerve showed a wider conduction velocity distribution with identification of more subgroups of nerve fibers than the motor nerve.ConclusionsThe conduction velocity distributions in high resolution on a peripheral motor and mixed nerve are different and this can be measured with the collision test.SignificanceWe provided ground truth data to verify the neuroimaging pipelines for the measurements of latency connectome in the peripheral nervous system. 相似文献
34.
目的:探讨冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证的疗效。方法:选择冠心病合并2型糖尿病患者98例,按随机数字表法分为对照组47例和观察组51例。对照组给予西医常规治疗措施; 观察组在对照组治疗基础上加用冠心康方加减治疗,1剂/次,2 次/d。连续治疗6个月后,比较两组血糖血脂水平、中医证候评分、脉搏波传导速度(PWV)以及临床疗效。结果:治疗后,观察组的空腹血糖(6.71±1.04)mmol/L、餐后2 h血糖为(10.63±1.94)mmol/L、HbA1c(7.13±0.97)%、TG(2.50±0.40)mmol/L,TC(3.94±0.55)mmol/L均低于对照组[(6.89±1.13)mmol/L、(10.93±2.03)mmol/L、(7.22±1.25)%、(2.53±0.36)mmol/L、(4.01±0.53)mmol/L],两组间比较差异有统计学意义(P<0.05)。治疗后观察组HDL-C(1.23±0.22)mmol/L 与对照组(1.19±0.21)mmol/L比较上升,而观察组LDL-C(2.61±0.34)mmol/L比对照组(2.67±0.37)mmol/L下降,组间比较差异无统计学意义(P>0.05)。治疗后,观察组患者中医证候评分(1.76±0.27)分及BS-PWV(5.90±0.64)m/s、ES-PWV(7.59±0.94)m/s均明显低于对照组的[(2.13±0.31)分、(6.41±0.77)m/s、(8.43±1.31)m/s](P<0.05)。观察组和对照组的总有效率分别为70.59%和59.57%,两组比较差异有统计学意义(P<0.05)。结论:冠心康方加减联合西药治疗冠心病合并2型糖尿病气虚痰瘀证可有效改善患者的血糖、血脂、中医证候以及动脉硬化,提高临床疗效。 相似文献
35.
Samo Lasi
Filip Szczepankiewicz Erica Dall'Armellina Arka Das Christopher Kelly Sven Plein Jürgen E. Schneider Markus Nilsson Irvin Teh 《NMR in biomedicine》2020,33(2)
Motion is a major confound in diffusion‐weighted imaging (DWI) in the body, and it is a common cause of image artefacts. The effects are particularly severe in cardiac applications, due to the nonrigid cyclical deformation of the myocardium. Spin echo‐based DWI commonly employs gradient moment‐nulling techniques to desensitise the acquisition to velocity and acceleration, ie, nulling gradient moments up to the 2nd order (M2‐nulled). However, current M2‐nulled DWI scans are limited to encode diffusion along a single direction at a time. We propose a method for designing b‐tensors of arbitrary shapes, including planar, spherical, prolate and oblate tensors, while nulling gradient moments up to the 2nd order and beyond. The design strategy comprises initialising the diffusion encoding gradients in two encoding blocks about the refocusing pulse, followed by appropriate scaling and rotation, which further enables nulling undesired effects of concomitant gradients. Proof‐of‐concept assessment of in vivo mean diffusivity (MD) was performed using linear and spherical tensor encoding (LTE and STE, respectively) in the hearts of five healthy volunteers. The results of the M2‐nulled STE showed that (a) the sequence was robust to cardiac motion, and (b) MD was higher than that acquired using standard M2‐nulled LTE, where diffusion‐weighting was applied in three orthogonal directions, which may be attributed to the presence of restricted diffusion and microscopic diffusion anisotropy. Provided adequate signal‐to‐noise ratio, STE could significantly shorten estimation of MD compared with the conventional LTE approach. Importantly, our theoretical analysis and the proposed gradient waveform design may be useful in microstructure imaging beyond diffusion tensor imaging where the effects of motion must be suppressed. 相似文献
36.
37.
《Clinical breast cancer》2020,20(6):e786-e793
IntroductionThe purpose of this study was to evaluate the diagnostic performance of superb microvascular imaging (SMI) in breast lesions.Materials and MethodsEighty-five solid breast lesions were studied with color Doppler flow imaging (CDFI), power Doppler imaging (PDI), monochromatic SMI (mSMI), and contrast-enhanced ultrasonography (CEUS). The penetrating vessels (PVs) and microvascular morphologic and distribution features of the breast tumors were evaluated for each modality.ResultsThe diagnostic accuracies of CDFI, PDI, mSMI, and CEUS were calculated and compared. Surgical pathologic analysis showed 47 benign and 38 malignant lesions. Compared with CDFI and PDI, mSMI and CEUS detected more PVs in breast lesions. The microvascular architecture showed significant differences between benign and malignant lesions. Benign lesions mainly displayed avascular, line-like, and branch-like patterns, and malignant lesions tended to display root hair-like and crab claw-like patterns. mSMI and CEUS identified more root hair-like and crab claw-like patterns in malignant lesions than CDFI and PDI. The sensitivity, negative predictive value, and accuracy of mSMI findings in diagnosing malignancy based on PVs and vascular patterns were both higher than those of CDFI and PDI.ConclusionsmSMI is equal to CEUS and superior to CDFI and PDI in identifying microvascular and discriminating malignant and benign breast masses. 相似文献
38.
39.
《Radiologia》2022,64(1):17-25
Vascular compression syndromes arise when a vessel in a tight anatomic space is entrapped by another structure, resulting in diverse symptoms for which different imaging tests are used to diagnose. Radiologists need to be familiar with vascular compression syndromes and to be able to identify their most representative findings. This paper aims to review the principal symptoms of vascular compression, describing and illustrating the key findings on Doppler ultrasonography that enable accurate diagnosis and guide further workup, avoiding unnecessary invasive tests and pointing to the appropriate treatment. 相似文献
40.
《Taiwanese journal of obstetrics & gynecology》2020,59(6):842-847
ObjectiveThis study aimed to evaluate whether state and trait anxiety among pregnant women were associated with fetoplacental Doppler findings, abnormal placental pathology, and placental angiogenic factors.Materials and methodsA total of 102 pregnant women at 32–35 gestational weeks were recruited and examined prospectively. State and trait anxiety were measured using the State-Trait Anxiety Inventory. Using Doppler ultrasound, pulsatility index (PI) of the umbilical artery (UA), middle cerebral artery (MCA), and uterine artery (UtA) and cerebroplacental ratio (CPR) were determined. Doppler parameters were converted into multiples of the median (MoM). Abnormal placental pathology was classified into 2 groups: vascular underperfusion (VU) and histological chorioamnionitis (HCA). Immunohistochemical analysis was performed to examine placental cells staining positive for placental growth factor (PLGF) and hypoxia-inducible factor-1-α (HIF-1α), which are markers for angiogenesis and hypoxic status, respectively.ResultsWomen with high state anxiety scores had low MCA-PI MoM and CPR MoM, while those with high trait anxiety scores had low MCA-PI MoM. VU was associated with a higher incidence of high trait anxiety scores, and HCA was associated with a higher incidence of high state and trait anxiety scores. Regression analysis showed a relationship between maternal state anxiety on MCA-PI MoM and HCA after controlling for covariates. Maternal trait anxiety exhibited relationships with VU and HCA after adjustment.ConclusionOur results demonstrated that maternal anxiety is associated with altered fetal cerebral blood flow and abnormal placental pathology but is not associated with uteroplacental insufficiency and placental angiogenic factors. 相似文献