It is an important means to study the electrical activity of the brain's nerve cells by exploring physiological information of the EEGs from the frequency domain. The gravity frequency is one of the global parameters with using this method. We used the multitaper spectrum method (MTM) spectrum estimation method of good performance to calculate the EEG spectrum and its gravity frequency of subjects under vigilance and vigilance decrement state. The results showed that the gravity frequency of vigilance state was higher than that of vigilance decrement state, the gravity frequency became smaller along with the vigilance decrement, and the location of the gravity frequency shifted to the left in the spectrum. Finally, the monitoring curve of the gravity frequency was acquired by designing an algorithm, and it was used to online monitoring vigilance operators.
In this paper, a new probe is proposed for the in vivo dielectric measurement of anisotropic tissue in radio frequency band, which could accomplish the dielectric measurement in perpendicular directions by one operation. The simulative studies are performed in the frequency range from 1–1 000 MHz in order to investigate the influence of probe dimension on the energy coupling and sensitivity of measurement. The suitable probe is designed and validated for the actual measurement in this frequency band. According to the simulation results, the energy coupling of the probe could be kept below –12 dB in the frequency range from 200–400 MHz with high sensitivity of measurement for the dielectric properties of anisotropic tissue. That indicates the new type of probe has the potential to achieve the dielectric measurement of anisotropic tissue in radio frequency band and could avoid the measurement error by multi-operations in the conventional method. This new type of probe could provide a new method for the in vivo dielectric measurement of anisotropic tissue in radio frequency band.
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.
Radiofrequency ablation for hepatic hemangioma is safe and effective, and can obtain the same curative effect as traditional surgical resection. For hepatic hemangiomas with large volume, abundant arterial blood supply and long ablation time, systemic inflammatory response syndrome (SIRS) often occurs after radiofrequency ablation, which can lead to injury or dysfunction of important organs. This paper systematically summarizes the mechanism, prevention and treatment of SIRS after radiofrequency ablation of hepatic hemangioma, so as to provide reference for improving the safety of radiofrequency ablation of hepatic hemangioma.
Objective To overview the systematic reviews/meta-analyses of radiofrequency ablation combined with transcatheter arterial chemoembolization for primary liver cancer. Methods We searched China National Knowledge Infrastructure, Wanfang, Chongqing VIP, SinoMed, PubMed, Embase, and Web of Science databases using computers, with a search deadline of December 31, 2022 for systematic reviews/meta-analyses of radiofrequency ablation combined with transcatheter arterial chemoembolization for primary liver cancer. The AMSTAR 2 scale, PRISMA statement, and GRADE grading system were used to evaluate the reporting quality, methodological quality, and evidence level. Results A total of 13 systematic reviews/meta-analyses were included, published from 2011 to 2022. The evaluation results of the AMSTAR 2 scale showed that 4 systematic reviews/meta-analyses were of low quality, while the rest were of extremely low quality, without medium to high quality systematic reviews/meta-analyses. The evaluation results of PRISMA statement showed that the scores of 9 systematic reviews/meta-analyses were 15-21, with certain reporting defects, and only 4 were relatively complete. The GRADE system evaluation of 75 evidence bodies for 9 clinical outcome indicators showed that there was no high quality of evidence, with medium quality accounting for 29%, low quality accounting for 32%, and extremely low quality accounting for 39%. Conclusions Radiofrequency ablation combined with transcatheter arterial chemoembolization can improve the 1-year and 3-year overall survival rates of patients with primary liver cancer with medium quality of evidence. However, its impact on 5-year overall survival rate, recurrence-free survival rate, complications, and whether it is more effective for hepatocellular carcinoma with a diameter of 3-5 cm still require more high-quality clinical research and systematic evaluation to verify.
For speech detection in Parkinson’s patients, we proposed a method based on time-frequency domain gradient statistics to analyze speech disorders of Parkinson’s patients. In this method, speech signal was first converted to time-frequency domain (time-frequency representation). In the process, the speech signal was divided into frames. Through calculation, each frame was Fourier transformed to obtain the energy spectrum, which was mapped to the image space for visualization. Secondly, deviations values of each energy data on time axis and frequency axis was counted. According to deviations values, the gradient statistical features were used to show the abrupt changes of energy value in different time-domains and frequency-domains. Finally, KNN classifier was applied to classify the extracted gradient statistical features. In this paper, experiments on different speech datasets of Parkinson’s patients showed that the gradient statistical features extracted in this paper had stronger clustering in classification. Compared with the classification results based on traditional features and deep learning features, the gradient statistical features extracted in this paper were better in classification accuracy, specificity and sensitivity. The experimental results show that the gradient statistical features proposed in this paper are feasible in speech classification diagnosis of Parkinson’s patients.
ObjectiveTo study the therapeutic efficacy of stereoelectroencephalography (SEEG)-guided radiofrequency thermo-coagulation ablation (RF-TC) in the treatment of tuberous sclerosis (TSC) related epilepsy and to investigate the prediction of the therapeutic response to SEEG-guided RF-TC for the efficacy of the subsequent surgical treatment. MethodsWe retrospectively analyze TSC patients who underwent SEEG phase II evaluation from January 2014 to January 2023, and to select patients who underwent RF-TC after completion of SEEG monitoring, study the seizure control of patients after RF-TC, and classify patients into effective and ineffective groups for RF-TC treatment according to the results of RF-TC treatment, compare the surgical outcomes of patients in the two groups after SEEG, to explore the prediction of surgical outcome by RF-TC treatment. Results59 patients with TSC were enrolled, 53 patients (89.83%) were genetic detection, of which 28 (52.83%) were TSC1-positive, 21 (39.62%) were TSC2-positive, and 4 (7.54%) were negative, with 33 (67.34%) de novo mutations. The side of the SEEG electrode placement: left hemisphere in 9 cases, right hemisphere in 13 cases, and bilateral hemisphere in 37 cases. 37 patients (62.71%) were seizure-free at 3 months, 31 patients (52.54%) were seizure-free at 6 months, 29 patients (49.15%) were seizure-free at 12 months, and 20 patients (39.21%) were seizure-free at 24 months or more. 11 patients had a seizure reduction of more than 75% after RF-TC, and the remaining 11 patients showed no significant change after RF-TC. There were 48 patients (81.35%) in the effective group and 11 patients (18.65%) in the ineffective group. In the effective group, 22 patients were performed focal tuber resection laser ablation, 19 cases were seizure-free (86.36%). In the ineffective group, 10 patients were performed focal tuber resection laser ablation, only 5 cases were seizure-free (50%), which was a significant difference between the two groups (P<0.05). ConclusionsOur data suggest that SEEG guided RF-TC is a safe and effective both diagnostic and therapeutic treatment for TSC-related epilepsy, and can assist in guiding the development of future resective surgical strategies and determining prognosis.
ObjectiveTo compare the clinical therapeutic efficacy of radiofrequency ablation (RFA) and external beam radiation (XRT) in the treatment of early hepatocellular carcinoma (HCC). MethodsThe early HCC patients were collected in the SEER (Surveillance, Epidemiology, and End Results) database, from 2010 to 2015, according to the established inclusion and exclusion criteria. The patients were assigned into an XRT group and a RFA group according to according treatment plans. The propensity score matching (PSM) was performed at a ratio of 1∶4 based on age, gender, race, alpha-fetoprotein (AFP), cirrhosis, and tumor diameter. The overall survival of the patients of the two groups was compared, and the risk factors affecting the long-term prognosis for the early HCC patients were analyzed. ResultsA total of 2 861 early HCC patients were collected, including 2 513 in the RFA group and 348 in the XRT group. After PSM, a total of 1 582 patients were enrolled, including 343 in the XRT group and 1 239 in the RFA group. After PSM, the proportion of tumor with larger diameter (>5 cm) in the XRT group was still higher than that in the RFA group (P<0.001), but there were no statistically significant differences in the other clinical pathological characteristics between them (P>0.05). The Kaplan-Meier survival curves of the RFA group was better than that of the XRT group (HR=1.65, P<0.001); The stratified analysis based on the tumor diameter revealed that the survival curves of the RFA group were superior to those of the XRT group in the HCC patients with tumor diameters <3 cm, 3–5 cm, and >5 cm (<3 cm: HR=1.79, P<0.001; 3–5 cm: HR=1.50, P<0.001; >5 cm: HR=1.67, P=0.003). The results of the multivariate Cox regression model analysis showed that the older age (≥65 years), higher AFP level (≥400 μg/L), larger tumor diameter (≥3 cm), and later AJCC stage (stage Ⅱ) were the risk factors for overall survival in the early HCC patients (HR>1, P<0.05), while the XRT treatment was a risk factor for shortening overall survival in the HCC patients [HR(95%CI)=1.62(1.41, 1.86), P<0.001]. ConclusionThe data analysis results from the SEER database suggest that the long-term overall survival of RFA treatment is superior to XRT treatment for patients with AJCC stage Ⅰ or Ⅱ.
Functional imaging method of biological electrical characteristics based on magneto-acoustic effect gives valuable information of tissue in early tumor diagnosis, therein time and frequency characteristics analysis of magneto-acoustic signal is important in image reconstruction. This paper proposes wave summing method based on Green function solution for acoustic source of magneto-acoustic effect. Simulations and analysis under quasi 1D transmission condition are carried out to time and frequency characteristics of magneto-acoustic signal of models with different thickness. Simulation results of magneto-acoustic signal were verified through experiments. Results of the simulation with different thickness showed that time-frequency characteristics of magneto-acoustic signal reflected thickness of sample. Thin sample, which is less than one wavelength of pulse, and thick sample, which is larger than one wavelength, showed different summed waveform and frequency characteristics, due to difference of summing thickness. Experimental results verified theoretical analysis and simulation results. This research has laid a foundation for acoustic source and conductivity reconstruction to the medium with different thickness in magneto-acoustic imaging.
Objective To explore therapeutic effect of radiofrequency ablation (RFA) guided by contrast-enhanced ultrasound in patient with advanced primary liver cancer following transcatheter arterial chemoembolization (TACE). Methods The patients with advanced primary liver cancer treated with the TACE firstly from January to December 2014 in this hospital were prospectively collected, then were randomly divided into a conventional ultrasound guided RFA group (control group) and contrast-enhanced ultrasound guided RFA group (study group). The complete ablation rate, liver function, serum alpha-fetoprotein (AFP) level, and 1-, 2-, and 3-year survival rates were observed in the two groups. Results A total of 42 patients with advanced primary liver cancer treated with the TACE were enrolled in this study, there were 21 patients in each group. ① There were no significant differences in the baseline data such as the gender, age, BCLC stage, AFP level, and Child grade of liver function between the two groups (P>0.05). ② All the treatments were completed according to the plan, no serious complications or treatment-related death happened. The complete ablation rate of the study group was significantly higher than that of the control group (χ2=5.717, P=0.017), and the AFP level was significantly lower than that of the control group (t=2.618, P=0.012). There was no significant difference in the Child grade of liver function between the 2 groups (P>0.05). ③ The rate of repeat RFA in the study group was significantly lower than that in the control group (χ2=4.434, P=0.035), and there was no significant difference in the TACE treatment rate between the two groups (χ2=1.659, P=0.197). ④ The survival rate of the study group was significantly better than that of the control group by comparing the survival curves (χ2=3.999, P=0.046). Conclusion Contrast-enhanced ultrasound guided RFA is superior to conventional ultrasound guided RFA in treatment of advanced primary liver cancer following TACE.