Hypertension is the primary disease that endangers human health. A convenient and accurate blood pressure measurement method can help to prevent the hypertension. This paper proposed a continuous blood pressure measurement method based on facial video signal. Firstly, color distortion filtering and independent component analysis were used to extract the video pulse wave of the region of interest in the facial video signal, and the multi-dimensional feature extraction of the pulse wave was preformed based on the time-frequency domain and physiological principles; Secondly, an integrated feature selection method was designed to extract the universal optimal feature subset; After that, we compared the single person blood pressure measurement models established by Elman neural network based on particle swarm optimization, support vector machine (SVM) and deep belief network; Finally, we used SVM algorithm to build a general blood pressure prediction model, which was compared and evaluated with the real blood pressure value. The experimental results showed that the blood pressure measurement results based on facial video were in good agreement with the standard blood pressure values. Comparing the estimated blood pressure from the video with standard blood pressure value, the mean absolute error (MAE) of systolic blood pressure was 4.9 mm Hg with a standard deviation (STD) of 5.9 mm Hg, and the MAE of diastolic blood pressure was 4.6 mm Hg with a STD of 5.0 mm Hg, which met the AAMI standards. The non-contact blood pressure measurement method based on video stream proposed in this paper can be used for blood pressure measurement.
目的：比较脑内血肿体积不同测量方法，为损伤程度鉴定提供更适用的依据。方法:将已知体积的模拟血肿经过CT扫描，用不同的测量方法测量其体积然后进行比较。结果：经统计学处理，CT 定量、体视学法、尺量法测得的体积与模拟血肿体积无显著差异，多田法测出的体积与模拟血肿体积有显著差异。结论：在司法实践中，体视法为测定脑内血肿的最简便适用方法。
ObjectiveTo evaluate the changes of the flow parameters before and after the anastomotic port exploration and dredging during coronary artery bypass grafting by using the transit time flow measurement (TTFM).MethodsA total of 167 patients who underwent continuous coronary artery bypass grafting and anastomotic port exploration and dredging surgery in Beijing Anzhen Hospital from 2018 to 2019 were enrolled in this study. There were 136 male and 31 female patients aged 41-82 (58.35±17.26) years. If the probe entered and exited the anastomotic port smoothly, it was recorded as a non-resistance group; if the resistance existed but the probe could pass and exit, it was recorded as a resistance group; if the probe could not pass the anastomotic port for obvious resistance, it was recorded as the stenosis group. In the stenosis group, the grafts were re-anastomosed and the flow parameters were re-measured by TTFM.ResultsA total of 202 anastomotic ports were carried out by exploration and dredging. Among them, 87 anastomosis (43.1%) were in the non-resistance group, and there was no significant change in the blood flow volume (BFV) and pulsatility index (PI) before and after exploration and dredging (6.16±3.41 mL/min vs. 6.18±3.44 mL/min, P=0.90; 7.06±2.84 vs. 6.96±2.49, P=0.50). Sixty-four anastomosis (31.7%) were in the resistance group, the BFV was higher after exploration and dredging than that before exploration and dredging (17.11±7.52 mL/min vs. 4.96±3.32 mL/min, P<0.01), while the PI was significantly smaller (3.78±2.20 vs. 8.58±2.97, P<0.01). Fifty-one anastomosis (25.2%) were in the stenosis group, and there was no significant change in the BFV and PI before and after exploration and dredging (3.44±1.95 mL/min vs. 3.48±2.11 mL/min, P=0.84; 10.74±4.12 vs. 10.54±4.11, P=0.36). After re-anastomosis, the BFV was higher (16.48±7.67 mL/min, P<0.01) and the PI deceased (3.43±1.39, P<0.01) than that before exploration and dredging.ConclusionThe application of anastomotic exploration and dredging can reduce the occurrence of re-anastomosis, and promptly find and solve the stenosis of the distal coronary artery, improve the poor perfusion of distal coronary, and thus improves the prognosis of patients.
The experiment performed on domestic pig, was designed to investigate the architecture of the stretching skin and the effect of tension traction on the wound closure. An 7 cm x 3.5 cm was drawn at a standard position. Drawing horizontal and vertical lines on the traction area, points of 1 cm apart were tattooed on the lines. A traction force measuring device was used to draw the wound edges together. Measurements of the distances between the points were made. An 7 cm x 10 cm wound was made on identical sites of each hind leg. In the experiment the traction tension was applied on the edges of wound immediately after the wound debridement. The results showed the stretched distance in the two areas was 5-7 times the width of the wound. The gain of skin from traction was 61-89 percent in the width of the wound. The wounds from traction five days could be closed 5 days after traction. It was concluded that the skin which could be used for traction was abundant. Wound closure with the skin traction technique had many advantages, such as rapid decreasing the size of wound and early closing of wound.
目的:探讨上颌单颌拔牙矫治的的临床效果、适应症。方法:选择18例安氏II类1分类错牙合患者采用上颌单颌拔牙模式矫治,对矫治前后X线头影测量数据进行对比分析。结果:① U1-SN增加4.84°,L1-MP增加2.78°,前牙覆盖减少4.06 mm,覆牙合减少3.39 mm,上唇突度减小1.39 mm、鼻唇角增大3.06°,Z角增大3.22°。② 18例患者矫治后侧貌明显改善,前牙覆牙合覆盖关系正常,磨牙呈完全远中关系,尖牙为中性关系。结论:上颌单颌拔牙模式适用于下唇突度小的轻度拥挤的轻度骨性和牙源性的Ⅱ类1分类错牙合。
To realize the accurate positioning and quantitative volume measurement of tumor in head and neck tumor CT images, we proposed a level set method based on augmented gradient. With the introduction of gradient information in the edge indicator function, our proposed level set model is adaptive to different intensity variation, and achieves accurate tumor segmentation. The segmentation result has been used to calculate tumor volume. In large volume tumor segmentation, the proposed level set method can reduce manual intervention and enhance the segmentation accuracy. Tumor volume calculation results are close to the gold standard. From the experiment results, the augmented gradient based level set method has achieved accurate head and neck tumor segmentation. It can provide useful information to computer aided diagnosis.
Dyspnea is the most common symptom in patients with acute heart failure syndrome (AHFS), and relieving dyspnea is an important goal in clinical practice, clinical trials and new drug regulatory approval. However, in clinical and scientific research, there is still no consensus on how to evaluate dyspnea, and there is still a lack of unified measurement methods. This article introduces the pathophysiological mechanism of dyspnea in acute heart failure, the measuring time of dyspnea, the posture of patients during measurement, the measuring conditions, and the common measurement methods of dyspnea in clinical trials and their advantages and disadvantages, so as to provide references for the selection of measurement methods of dyspnea in clinical trials of acute heart failure.
The anterior cruciate ligament (ACL) reconstruction mostly relies on the experience of surgeons. To improve the effectiveness and adaptability of the tension after ACL reconstruction in knee joint rehabilitation, this paper establishes a lateral force measurement model with relaxation characteristics and designs an on-line stiffness measurement system of ACL. In this paper, we selected 20 sheep knee joints as experimental material for the knee joint stability test before the ACL reconstruction operation, which were divided into two groups for a comparative test of single-bundle ACL reconstruction through the anterolateral approach. The first group of surgeons carried out intraoperative detection with routine procedures. The second group used ACL on-line stiffness measurement system for intraoperative detection. After that, the above two groups were tested for postoperative stability. The study results show that the tension accuracy is (− 2.3 ± 0.04)%, and the displacement error is (1.5 ± 1.8)%. The forward stability, internal rotation stability, and external rotation stability of the two groups were better than those before operation (P < 0.05). But the data of the group using the system were closer to the preoperative knee joint measurement index, and there was no significant difference between them (P > 0.05). The system established in this paper is expected to help clinicians judge the ACL reconstruction tension in the operation process and effectively improve the surgical effect.