ObjectiveTo analyze the feasibility and effectiveness of elastic intramedullary nail fixation for the fifth metacarpal neck fracture under the guidance of high frequency ultrasound.MethodsThe clinical data of 30 patients with the fifth metacarpal neck fractures who were treated with elastic intramedullary nails fixation under the guidance of high frequency ultrasound and met the selection criteria between May 2013 and September 2017 were retrospectively analysed. There were 24 males and 6 females, the age ranged from 18 to 58 years, with an average of 31.4 years. The head-shaft angle of the fifth metacarpal was (55.6±11.3)°. The time from injury to operation was 12 hours to 8 days, with an average of 2.4 days. The operation time, number of intraoperative fluoroscopy, fracture reduction, complications, and fracture healing time were recorded. The head-shaft angle of the fifth metacarpal on the affected side after fracture healing were measured and compared with the healthy side. At last follow-up, the active range of motion of the fifth metacarpophalangeal joint of both sides were measured, and the function was evaluated by using the total active movement (TAM) evaluation standard of the Hand Surgery Association of Chinese Medical Association.ResultsThe operation time was 22-40 minutes, with an average of 32.4 minutes; the intraoperative fluoroscopy was performed once; ultrasound images and X-ray fluoroscopy showed that the fracture was well reduced and no adjustment was required. The incisions healed well after operation, without tendon adhesion or local numbness. All 30 patients were followed up 8-16 months, with an average of 11.7 months. The fracture healing time was 4-8 weeks, with an average of 5.6 weeks. The head-shaft angle of the fifth metacarpal was (13.2±1.4)°, which was significantly improved when compared with preoperative value (t=?20.02, P=0.00); and there was no significant difference (t=1.94, P=0.06) when compared with the healthy side [(12.6±1.0)°]. At last follow-up, the active range of motion of the fifth metacarpophalangeal joint on the affected side was (89.4±2.4)°, showing no significant difference (t=?1.58, P=0.13) when compared with the healthy side [(90.3±2.0)°]. According to the TAM evaluation standard of the Hand Surgery Association of Chinese Medical Association, all patients were considered to be excellent.ConclusionThe effectiveness of elastic intramedullary nail fixation for the fifth metacarpal neck fracture under the guidance of high frequency ultrasound is definite. It can dynamically observe the fracture reduction from different angles, reduce ionizing radiation and postoperative complications.
Objective To investigate the impact of injection of acetic acid hypertonic saline solution (AHS) in dog liver during radiofrequency ablation (RFA) on its destructive zone. Methods RFAs were performed in dog livers by using LDRF-120S mutiple probe ablation system combining 50% acetic acid 5% hypertonic saline solution injection. Thirty healthy adult hybrid dogs were randomly divided into 5 groups (n=6). Group A: RFA was performed immediately after injection of 2 ml AHS; Group B: RFA was performed 5 min after injection of 2 ml AHS; Group C: RFA was performed immediately after injection of 4 ml AHS; Group D: RFA was performed 5 min after injection of 4 ml AHS; Group E: RFA was performed immediately after injection of 6 ml AHS. Results There were no significant differences in the mean initial impedance within 5 groups. The mean ablation times were different significantly among 5 groups (F=83.831, P＜0.001). The mean ablation time was different significantly between any two groups by LSD-t analysis (P＜0.001). The mean coagulation diameters were different significantly among 5 groups （F=53.488, P＜0.001）. The mean coagulation diameter of group E was the largest among 5 groups. Besides mean coagulation diameter was no significant difference between group D and E (Pgt;0.05), the mean coagulation diameter was different significantly between any two groups by LSD-t analysis (P＜0.001). Obviously thrombus were shown in coagulation necrosis zone and nearly normal tissue with gordon amp; sweet. AHS spillage from the injection site occurred in group E. Four dogs died in group E within 14 d but no dog died in the other groups. Conclusion RFA is performed 5 min after injection of 4 ml AHS in dog liver produces the ideal ablation destructive zone.
Objective To report the preliminary results of intraoperative saline-irrigated radiofrequency modified maze procedure for chronic atrial fibrillation (AF) in mitral valve diseases. Methods From May 2003 to April 2004 forty-one patients underwent intraoperative saline-irrigated modified maze procedure. The patients included 13 male and 28 female. Their age ranged from 27-65 years (46±10 years). The duration of AF varied from 5 months to 15 years (4.5±3.6 years).The left atrial diameter varied from 37-93 mm (54±11mm). There were mitral stenosis 20, mitral regurgitation 1 and mitral stenosis with regurgitation 20 cases. Cardiopulmonary bypass (CPB) was established as usual. Ablation lines were made with Cardioblate (Medtronic, 25-30 W, 180-240ml/h). Having finished right-sided maze procedure, the aorta was cross-clamped and cold crystalloid or blood cardioplegia were used for myocardial protection. Left atrial incision was performed through the interatrial groove. The ablation lines were created to encircle the orifices of the left and right pulmonary veins respectively. The ablation lines were also performed from the left encircling line to the posterior mitral valvular annulus and to the orifice of left atrial appendage respectively. A ablation line was used to connect left and right pulmonary veins circumferential line. Concomitant procedures were performed (there were double valve replacement 10 cases, mitral valve replacement 31 cases, tricuspid annuloplasty 6 cases, removing the left atrial thrombi 6 cases). Results CPB time varied from 71-160 min (105±24 min) and cross-clamping time varied from 32-106 min (62±20 min). The ablation time varied from 4-22 min (11±4 min). One patient died during hospitalization and the death was caused by acute mechanic valve obstruction. During follow-up at discharge and 3 months 35% patients (14/40) were free of AF and the others were not. But at 6 months 67% patients (10/15) were free of AF. Conclusion The intraoperative saline-irrigated radiofrequency modified maze procedure is comparatively simpler and its efficacy is satisfactory.
ObjectiveTo analyze the clinical presentations and radiological characteristics of pulmonary vein stenosis after radiofrequency ablation.
MethodsClinical and radiological data of 2 patients with pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation were retrospectively analyzed and literatures were reviewed.
ResultsBoth patients had undergone circumferential pulmonary vein isolation. The symptoms appeared approximately 2 months after the operation. The major symptoms were cough, hemoptysis, exacerbation of dyspnea and chest pain. Both patients were misdiagnosed as other diseases such as pneumonia in other hospitals, and the anti-infection therapy was invalid. Both CT scans showed parenchymal exudative consolidation with varying degrees of interstitial septal thickening and small nodules. Both patients were confirmed as pulmonary vein stenosis by CT angiography. Literature review identified 21 cases of pulmonary vein stenosis after radiofrequency ablation for atrial fibrillation. The main clinical features are hemoptysis, chest pain, shortness of breath and cough. The most common features of thoracic radiological imaging are consolidation, groud-glass attenuation, pleural effusion and interstitial septal thickening.
ConclusionsIf a patient presents with hemoptysis, dyspnea, chest pain or other clinical manifestations after ablation therapy and image findings show parenchymal exudative consolidation with interstitial septal thickening and multiple small nodules, the possibility of pulmonary vein stenosis should be considered. Contrast-enhanced CT combined with pulmonary vein imaging technology can clearly show the opening diameter of each pulmonary vein and its branches, so it is an important non-invasive examination method for the evaluation and diagnosis of pulmonary vein stenosis.
摘要:目的:探討三維電解剖標測系統(CARTO)指導下進行房性心動過速射頻消融的方法及效果。方法:對40例房性心動過速患者應用CARTO標測心房, 構建三維電解剖圖,分析房性心動過速的電生理機制。局灶性房速消融最早激動點,大折返性房速消融折返環的關鍵性峽部。選擇利用常規方法行消融的28 例患者作為對照組。比較兩組消融的成功率、X線曝光時間。結果:38例患者CARTO三維標測系統標測提示為局灶性房性心動過速, 最早激動點位于右心房35例,其中冠狀靜脈竇口8例(20%)、間隔部10例(25%)、側壁8例(20%)、上腔靜脈口附近4例(10%)、后壁4例(10 %),1例患者(2.5%)有3種類型房速(分別為間隔部、上腔靜脈口的局灶房速和三尖瓣峽部依賴的大折返房速)。位于左心房的局灶房速3例,分別位于右上肺靜脈口(2.5%)、左上肺靜脈口(2.5%)及左心耳(2.5%)。2例患者為大折返房速(5%),1例為三尖瓣峽部依賴性,1例為圍繞界嵴的大折返房速。均消融成功(100%),隨訪4~16個月,均無復發。常規消融組成功率為89.3%(Plt;0.05)。CARTO組X線曝光時間比常規組明顯縮短,分別為(13.8±5.5 ) min 和( 30.4±12.9 ) min,差異有統計學意義（Plt;0.05）。結論:應用CARTO標測房性心動過速, 對分析房性心動過速的機制準確快速, 能有效指導射頻消融。Abstract: Objective: To evaluate the methods and effects of radiofrequency ablation of atrial tachycardia guided by CARTO. Methods: The atria of 40 cases were mapped by three dimensional electroanatomic mapping system. In order to analyse the mechanism of atrial tachycardia and perform the ablation of the earliest excited point in focal atrial tachycardia and isthmus in macroreentry atrial tachycardia. 28 cases ablated by conventional procedure were selected as controlled group. The success rate and fluoroscopic time were compared between the two groups. Results: Focal atrial tachycardia was seen in 38 patients. The sites of origin from right atrium were at the coronary sinus ostium in 8 cases (20%), septal in 10 cases (25%), lateral wall in 8 cases (20%), superior vena cava ostium in 4 cases (10%), posterior wall in 4 cases (10%). One case had 3 types of atrial tachycardia (2.5%). The sites of origin from left atrium were at right pulmonary vein ostium in 1 case (2.5%), left pulmonary vein ostium in 1 case (2.5%), left auricular appendage in 1 case (2.5%). 2 cases were macroreentry atrial tachycardia (5%). Ablation was performed successfully (100%) without any complication. No recurrence was found during a followup of 416 months. Success rate in conventional group was 89.3%(Plt;0.05)。Comparing the CARTO group and conventional group, the fluoroscopic time was shorter, ( 13.8±5.5 ) min vs ( 30.4±12.9 ) min （Plt;0.05).Conclusion: The mechanism of atrial tachycardia can be evaluated quickly and accurately. Ablation can be performed safely and effectively guided by CARTO.
The possible influence of electromagnetic field (EMF) on the function of neural systems has been widely concerned. In this article, we intend to investigate the effects of long term power frequency EMF exposure on brain cognitive functions and it’s mechanism. The Sprague-Dawley (SD) rats were randomly divided into 3 groups: the rats in EMF Ⅰ group were placed in the 2 mT power frequency EMF for 24 days. The rats in EMF Ⅱ group were placed in the 2 mT power frequency EMF for 48 days. The rats in control group were not exposed to the EMF. Then, the 16 channel local field potentials (LFPs) were recorded from rats’ prefrontal cortex (PFC) in each group during the working memory (WM) tasks. The causal networks of LFPs were also established by applying the directed transfer function (DTF). Based on that, the differences of behavior and the LFPs network connection patterns between different groups were compared in order to investigate the influence of long term power frequency EMF exposure on working memory. The results showed the rats in the EMF Ⅱ group needed more training to reach the task correction criterion (over 80%). Moreover, the causal network connection strength and the global efficiency of the rats in EMF Ⅰ and EMF Ⅱ groups were significantly lower than the corresponding values of the control group. Meanwhile, significant differences of causal density values were found between EMF Ⅱ group and the other two groups. These results indicate that long term exposure to 2 mT power frequency EMF will reduce the connection strength and the information transfer efficiency of the LFPs causal network in the PFC, as well as the behavior performance of the rats. These results may explain the effect of EMF exposure on working memory from the view of neural network connectivity and provide a support for further studies on the mechanism of the effect of EMF on cognition.
ObjectiveTo observe the accuracy of location and operation of traditional blind acupotomy lysis in the treatment of scapulohumeral periarthritis by using the high-frequency ultrasound.MethodsForty-two patients with scapulohumeral periarthritis diagnosed in the First Affiliated Hospital of Xinjiang Medical University and Urumqi Hospital of Traditional Chinese Medicine from February to April 2018 were selected. Four common sites of needle knife in the treatment of scapulohumeral periarthritis were operated blindly, and the process of the needle insertion points location and needle perform were both observed by high-frequency ultrasound.ResultsUsing high-frequency ultrasound to observe and confirm the bare-handed positioning point and needle-knife operating point, we found that the accuracy rate of bare-handed positioning needle-point was 100.0% (42/42). In the process of needling, the accuracies of needle insertion at the point of small tubercle of humerus and the point of bursa of deltoid muscle were high, which was 95.2% (40/42) and 100.0% (42/42), respectively. However, because of the deviation of the needle depth and direction, the accuracies of needle insertion at the coracoid point and the sulcus point between the humeral tubercles were low, which was 45.2% (19/42) and 4.8% (2/42), respectively.ConclusionsTraditional acupotomy lysis is a commonly used method of needle knife treatment. Using high-frequency ultrasound, it is found that even by experienced needle knife doctors, there may still be positioning deviation when using blind method to insert needles. Because the visualization of clinical needle knife is difficult to be carried out universally due to the limitations of time and technology, it is suggested that high-frequency ultrasound could be used as a visualization teaching tool in the training of needle knife operation to assist the training of blind needle knife operation technology, which may improve the accuracy of blind needle knife operation.
Critical flicker fusion frequency (CFF) is a dynamic visual function test that measures the minimum frequency at which a flicker source is perceived by the visual system as continuous light. The measurement method is convenient, the inspection time is short, and it can be effectively evaluated in the case of refractive interstitial opacity. Although CFF has many advantages, its application in the field of ophthalmology has not received sufficient attention. The pathway of CFF involves the pathway from the retina to the lateral geniculate body to the primary visual cortex, where the macrocellular pathway is sensitive to temporal resolution and responsible for transmitting rapidly changing information. Its measurements typically use red, green, or yellow light as a flashing light source to detect the functional integrity of the macular region. As a subjective test, the results of CFF can be affected by a variety of factors, such as drug use, fatigue, and luminous intensity. In order to improve the repeatability of the measurement, it is necessary to follow standardized measurement steps. CFF has important application value in the diagnosis of optic nerve diseases. It can assist in diagnosing the presence of optic neuropathy, evaluating the conduction function of the optic nerve, and monitoring the progression of the disease and the effect of treatment. As a convenient and efficient visual function evaluation tool, CFF has great potential in the diagnosis of optic nerve diseases and visual function monitoring. In view of its application prospects in the field of ophthalmology, this study calls for more attention and support from ophthalmologists, and carry out related basic and clinical research to further explore the application value of CFF in different disease conditions.
Trying to provide ultrasonic image-aid measures for quantitative diagnosis and dynamic monitoring of liver fibrosis, we propose two scoring methods for liver fibrosis tissue in vivo, based on ultrasound radio frequency (RF) time series in this paper. Firstly, RF echo signals of human liver were recorded in this study. Then one of the recorded frame RF data was demodulated to be B model image. After that, a region of interest (ROI) in the B model image was selected. For each point in the ROI, its all frame data were acquired so that RF time series were formed. An SMR (size measure relationship) fractal dimension and six spectral features were extracted from RF time series in the ROI. With relative deviation and Fisher's discriminant ratio, seven features were weighted and summed so that the liver tissues' scores were obtained, Score-rd and Score-fisher, respectively. Area under ROC curve (AUC) and a support vector machine (SVM) were used to evaluate whether these scoring methods would be useful in distinguishing normal and cirrhosis tissues. Experimental results are shown as follows: Score-rd's AUC was 0.843, while Score-fisher was 0.816, SVM classification accuracies were both up to 87.5%. This proved that our proposed scoring methods were effective in distinguishing normal and cirrhosis tissues. Score-rd and Score-fisher have potential for clinical applications. They can also provide quantitative references for liver fibrosis diagnosis.
Traditionally, adequate tidal volume is considered to be a necessary condition to support respiratory patient breathing. But the high frequency ventilation (HFV) with a small tidal volume can still support the respiratory patient breathing well. In order to further explore the mechanisms of HFV, the pendelluft ventilation between left and right lungs was proposed in this paper. And a test platform by using two fresh sheep lungs was developed for investigating the pendelluft ventilation between the left and right lungs. Furthermore, considering the viscous resistance (R), inertance (I) and lung compliance (C) in the lung, a second-order lung ventilation model was designed to inspect and evaluate the pendelluft ventilation between left lung and right lungs. On referring to both results of experiments in practice and simulation in MATLAB Simulink, between the left and right lungs, the phase difference in their airflow happens during HFV at some frequencies. And the pendelluft ventilation between the left and right lungs is resulted by the phase difference, even if the total airflow entering a whole lung is 0. Under HFV, the pendelluft ventilation between left and right lungs will benefit the lungs being more adequately ventilated, and will be improve the utilization rate of oxygen in the lungs.
