The dose data produced by treatment plan system (TPS) in intensity-modulated radiation therapy (IMRT) has many gradient edge points. Considering this feature we proposed a new interpolation algorithm called treatment plan dose interpolation algorithm based on gradient feature in intensity-modulated radiation therapy (TDAGI), which improves the Canny algorithm to detect the gradient edge points and non-edge points by using the gradient information in the dose data plane. For each gradient edge point, the corresponding gradient profile was traced and the profile's sharpness was calculated, and for each non-edge point, the dispersion was calculated. With the sharpness or dispersion, the kernel coefficients of bi-cubic interpolation can be obtained and can be used as the central point to complete the bi-cubic interpolation calculation. Compared with bi-cubic interpolation and bilinear interpolation, the TDAGI algorithm is more accurate. Furthermore, the TDAGI algorithm has the advantage of gradient keeping. Therefore, TDAGI can be used as an alternative method in the dose interpolation of TPS in IMRT.
Low-intensity ultrasound stimulation of the retina has the ability to modulate neural activity in the primary visual cortex (V1), however, it is currently unclear how different intensities and durations of ultrasonic stimulation of the retina modulate neural activity in V1. In this paper, we recorded local field potential (LFP) signals in the V1 brain region of mice under different ultrasound intensities and different stimulation times. The amplitude of LFP corresponding to 1 s before ultrasound stimulation to 2 s after stimulation (–1–2 s) was analyzed, including the power and sample entropy of delta, theta, alpha beta, and low gamma frequency bands. The experimental results showed that, as the stimulation intensity increased, the peak value of the LFP in the visual cortex showed a linear upward trend; the power in the delta and theta frequency bands showed a linear upward trend, and the sample entropy showed a linear downward trend. With increases of stimulation duration, the peak value of the LFP in the visual cortex showed an upward trend, and the upward trend gradually weakened; the power in the delta frequency band showed an upward trend, the sample entropy showed a linear upward trend, and the sample entropy in the theta frequency band showed a downward trend. The results show that low-intensity ultrasonic stimulation of the retina has a significant modulatory effect on neural activity in the visual cortex. The study provides insights into the mechanisms by which ultrasonic stimulation regulates visual system function. Furthermore, it clarifies the patterns of parameter selection, facilitating the development of personalized multi-parameter modulation for the treatment of visual neural degeneration, retinal disorders and related research areas.
In this paper, a method for dose calculation with pencil beam kernels constructed by point kernel superposition was proposed to accelerate the dose calculation during intensity optimization iteration. With this method, the direct aperture optimization method can be integrated in the planning system based on point kernel convolution/superposition model. The dose calculation time was also reduced during the iteration. From the result of the phantom and clinical patient data test, it was concluded that this method could be used for the intensity optimization of iteration dose calculation as the satisfied precision due to the optimization result coherence obtained. By implementing the method in the planning system product based on point kernel convolution/superposition model, a lot of additional research and development works for the pencil beam dose calculation model as well as the product maintenance cost can be avoided.
In order to get high-resolution glomerulus image with large field of view (FOV), stitching multiple small FOV images with high-resolution is necessary. Directly stitching images without properly correction is not acceptable and cannot afford any significant assistance in pathological diagnosis for intensity inhomogeneity and geometric distortion. Therefore we proposed a method of distortion correction and intensity inhomogeneity correction of glomerulus transmission electron microscope (TEM) image. In this paper, we firstly describe how these two distortions degrade images. Secondly, based on the TEM imaging system, image acquisition model and distortion correction model were proposed. Then according to these two models, distortions were greatly degraded and stitching results were improved by respectively applying two corrections, intensity inhomogeneity correction and geometric distortion correction. With the method proposed here, the result was improved significantly and stripes, fuzzy and artifacts were decreased dramatically. Our method has been proved to be valid to solve the problems of TEM glomerulus image distortion and at the same time to improve the result of multiple TEM glomerulus image stitching.
Objective To explore the effects of low-intensity pulsed ultrasound (LIPUS) on anabolism, apoptosis and intraflagellar transport 88 (IFT88) expression in mouse chondrocytes after interleukin (IL)-1β intervention, and the correlation of cartilage repairment by LIPUS with primary cilia. Methods IL-1β intervention, LIPUS intervention and lentiviral carrying IFT88-specifific short hairpin RNA (sh-IFT88) transfection were performed on mouse chondrocytes, respectively. The groups included: normal chondrocyte group (N group), chondrocyte after IL-1β intervention group (OA group), chondrocyte after IL-1β intervention+LIPUS group (OA+U group), sh-IFT88+IL-1β intervention chondrocyte group (KO+OA group), and sh-IFT88+LIPUS+IL-1β treated chondrocyte group (KO+OA+U group). Real-time polymerase chain reaction and immunofluorescence were used to determine the expression of collagen Ⅱ, aggrecan, and primary cilia, and apoptosis was measured by flow cytometry. All experimental data were statistically analyzed using the GraphPad Prism 9.5 software. Results The expression of collagen Ⅱ and aggrecan increased, the apoptosis decreased, and the incidence of primary cilia in chondrocytes of mice increased in the OA+U group compared with those in the OA group (P<0.05). The collagen Ⅱ and aggrecan expression decreased and the apoptosis increased in the KO+OA+U group compared with those in the OA+U group (P<0.05). Conclusion LIPUS can reduce the apoptosis of chondrocytes in C57 mice after IL-1β intervention, and increase the expression of collagen Ⅱ and aggrecan in chondrocyte matrix, and the effect is related to primary cilia.
ObjectiveTo explore the application value of high intensity focused ultrasound (HIFU) in the treatment of advanced pancreatic cancer.MethodThe domestic and foreign literatures about studies of HIFU treating advanced pancreatic cancer in recent years were retrieved and summarized.ResultsHIFU could prolong the survival time, control pain, and enhance the body’s immune function in patients with advanced pancreatic cancer. There were no obvious serious complications during the treatment process. The combined treatment with radiotherapy, chemotherapy, and traditional Chinese medicine could obviously prolong the survival time and improve the quality of life for the patients with advanced pancreatic cancer.ConclusionsHIFU is an important component in the comprehensive treatment of advanced pancreatic cancer. However, because there is no uniform standard for the dosage of HIFU treatment, the sample size of many related studies is small, so the research results have certain limitations, so more studies are needed to improve their understanding of advanced pancreatic cancer in order to better serve clinical workin future.
Objective To explore the differential diagnosis significance of 3.0T MRI united-sequences examination in the diagnosis of benign and malignant breast lesions. Methods A total of 67 breast lesions of 59 patients were collected prospectively, which be treated at the Sichuan Provincial People’s Hospital during July 2015 to January 2017. All patients were underwent bilateral breast 3.0T magnetic resonance plain scan, diffusion weighted imaging, and dynamic enhanced scan successively before surgical operation. Analysis of morphological features of the benign and malignant breast lesions, the time-signal intensity curve (TIC), the apparent diffusion coefficient (ADC), and the combination diagnosis of them were performed. Results Of all 59 patients, 67 lesions were confirmed by histopathology, including 18 benign lesions and 49 malignant lesions. The morphological features (including margin, shape, border, and evenness), the types of TIC of dynamic enhancement, and ADC value between the benign lesions and malignant lesions were statistically significant (P<0.05). The sensitivity and specificity of Fischer scoring system was 89.8% (44/49) and 61.1% (11/18) respectively. The sensitivity and specificity of TIC types was 83.7% (41/49) and 77.8% (14/18) respectively. The diagnostic threshold of ADC value was 1.012×10–3 mm2/s, with the sensitivity and specificity for the diagnosis was 91.8% (45/49) and 83.3% (15/18) respectively. The sensitivity and specificity of the combination of Fischer scoring system and TIC type for diagnosis between benign and malignant breast lesions was 95.9% (47/49) and 72.2% (13/18) respectively. The sensitivity and specificity of the combination of Fischer scoring system, TIC type, and ADC value for benign and malignant breast lesions was 98.0% (48/49) and 83.3% (15/18) respectively. Conclusion The combination of Fischer scoring system, TIC type, and diffusion-weighted imaging for the differential diagnosis between benign lesions and malignant lesions was more effective than single imaging method.
Aiming at the disadvantages of traditional direct aperture optimization (DAO) method, such as slow convergence rate, prone to stagnation and weak global searching ability, a gradient-based direct aperture optimization (GDAO) is proposed. In this work, two different optimization methods are used to optimize the shapes and the weights of the apertures. Firstly, in order to improve the validity of the aperture shapes optimization of each search, the traditional simulated annealing (SA) algorithm is improved, the gradient is introduced to the algorithm. The shapes of the apertures are optimized by the gradient based SA method. At the same time, the constraints between the leaves of multileaf collimator (MLC) have been fully considered, the optimized aperture shapes are meeting the requirements of clinical radiation therapy. After that, the weights of the apertures are optimized by the limited-memory BFGS for bound-constrained (L-BFGS-B) algorithm, which is simple in calculation, fast in convergence rate, and suitable for solving large scale constrained optimization. Compared with the traditional SA algorithm, the time cost of this program decreased by 15.90%; the minimum dose for the planning target volume was improved by 0.29%, the highest dose for the planning target volume was reduced by 0.45%; the highest dose for the bladder and rectum, which are the organs at risk, decreased by 0.25% and 0.09%, respectively. The results of experiment show that the new algorithm can produce highly efficient treatment planning a short time and can be used in clinical practice.
Objective To explore the effectiveness and appropriate energy parameters of high-intensity focused ultrasound (HIFU) in treating infant hemangiomas. Methods Between January 2009 and September 2010, 60 infants with hemangioma were treated. There were 23 boys and 37 girls, aged from 3 to 30 months with an average of 10 months. These hemangiomas were located at head and face (24 cases), trunk (15 cases), l imb (16 cases), buttocks (2 cases), perineum (1 case),and multiple lesions (cervix, abdomen, and upper l imbs, 2 cases). The size of hemangiomas ranged from 0.8 cm × 0.6 cm to 6.0 cm × 5.0 cm. The 60 infants were randomly divided into 3 groups: groups A, B, and C (n=20) based on different ultrasound energies used in treatment. The lesion surface was irradiated with 3-5 mm/second for 5 continuously by ultrasonic therapeutic apparatus at a frequency of 9 MHz, impulse of 1 000, and 10% of scanning overlap; the powers of 3.5, 4.0, and 4.5 W were used in groups A, B, and C, respectively, 3 times as a course of treatment with 1 month interval. The effect and ulcer and scar risk in irradiation region were observed after 6 months of treatment. Results All cases were treated for one course. After 6 months of treatment, no significant difference in the effect was found among 3 groups based on hemangioma treatment judging criterion (P gt; 0.05). Neither ulcer nor scar occurred in group A; ulcer occurred in 4 cases (20%) of group B with superficial scars, and in 7 cases (35%) of group C with obvious scars. The rates of ulcer and scar in groups B and C were significantly higher than that in group A (P lt; 0.05). Conclusion HIFU irradiating is one of effective methods for treating infant hemangioma, but the appropriate energy was below 3.5 W.
Objectives To systematically analyze the effect of high-intensity and low-intensity resistance training on glycosylated hemoglobin (HbA1c) in elderly patients with type 2 diabetes. Methods PubMed, EBSCO, Cochrane Library, Web of science, Wanfang, Chinese National Knowledge Infrastructure and Chongqing VIP were searched to collect randomized controlled trials of resistance training intervention in elderly patients with type 2 diabetes. The search time limit was from the establishment of the database to August 28, 2021, and the RevMan 5.3 and Stata 15.0 software were used for meta-analysis. Results A total of 415 patients in 8 articles were included in this study. A subgroup analysis based on control measures showed that compared with the resistance training group, the HbA1c level effect value of the non- training group was weighted mean difference (WMD) = ?0.54% [95% confidence interval (CI) (?1.06%, ?0.03%), P=0.04)], the HbA1c level effect value of the flexibility training group was WMD=?0.47% [95%CI (?1.05%, 0.12%), P=0.12], the HbA1c level effect value of the aerobic training group was WMD=?0.10% [95%CI (?0.71%, 0.51%), P=0.75]. Subgroup analysis of resistance strength showed that compared with the flexibility or non-resistance training group, both high-intensity [WMD=?0.99%, 95%CI (?1.16%, ?0.81%), P<0.00001] and low- and medium-intensity resistance training [WMD=?0.29%, 95%CI (?0.58%, ?0.01%), P=0.05] can reduce HbA1c. Compared with the high-intensity resistance training, the HbA1c level effect value of the low- and medium-intensity resistance training was WMD=0.03% [95%CI (?0.33%, 0.39%), P=0.88]. Compared with the low- and medium-intensity resistance training, the HbA1c level effect value of the low- and medium-intensity aerobic training was WMD=?0.10% [95%CI (?0.71%, 0.51%), P=0.75]. Among all the included studies, only the high-intensity resistance training group reported multiple adverse events.ConclusionsCurrent evidence suggests that elderly patients with type 2 diabetes are more suitable to choose low-to-medium-intensity resistance training to control HbA1c. It is recommended that elderly patients with type 2 diabetes take 60% to 75% of the maximum muscle strength of medium-intensity resistance training.