Sodium Alginate Ultrasound Phantom for Medical Education

2021 ◽  
pp. 016173462110186
Author(s):  
Minoru Aoyagi

The ultrasound phantoms used to educate medical students should not only closely mimic the ultrasound characteristics of human soft tissues but also be inexpensive and easy to manufacture. I have been studying handmade ultrasound phantoms and proposed an ultrasound phantom comprising calcium alginate hydrogel that met these requirements but caused a speckle pattern similar to that observed in ultrasound images of liver. In this study, I show that adding ethanol to the precursors used to fabricate the phantom reduces the speckle pattern. The ultrasound propagation velocity and attenuation coefficient of the phantom were 1561 ± 8 m/s and 0.54 ± 0.18 dB/cm/MHz, respectively (mean ± standard deviation), which are within the ranges of those in human soft tissues (1530-1600 m/s and 0.3-1.0 dB/cm/MHz, respectively). This phantom is easy to fabricate without special equipment, is inexpensive, and is suitable for elementary training on ultrasound diagnosis, operation of ultrasound-guided needles, and blind catheter insertion.

Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 264
Author(s):  
Ben-Yi Liau ◽  
Fu-Lien Wu ◽  
Keying Zhang ◽  
Chi-Wen Lung ◽  
Chunmei Cao ◽  
...  

Walking performance is usually assessed by linear analysis of walking outcome measures. However, human movements consist of both linear and nonlinear complexity components. The purpose of this study was to use bidimensional multiscale entropy analysis of ultrasound images to evaluate the effects of various walking intensities on plantar soft tissues. Twelve participants were recruited to perform six walking protocols, consisting of three speeds (slow at 1.8 mph, moderate at 3.6 mph, and fast at 5.4 mph) for two durations (10 and 20 min). A B-mode ultrasound was used to assess plantar soft tissues before and after six walking protocols. Bidimensional multiscale entropy (MSE2D) and the Complexity Index (CI) were used to quantify the changes in irregularity of the ultrasound images of the plantar soft tissues. The results showed that the CI of ultrasound images after 20 min walking increased when compared to before walking (CI4: 0.39 vs. 0.35; CI5: 0.48 vs. 0.43, p < 0.05). When comparing 20 and 10 min walking protocols at 3.6 mph, the CI was higher after 20 min walking than after 10 min walking (CI4: 0.39 vs. 0.36, p < 0.05; and CI5: 0.48 vs. 0.44, p < 0.05). This is the first study to use bidimensional multiscale entropy analysis of ultrasound images to assess plantar soft tissues after various walking intensities.


2016 ◽  
Vol 133 (36) ◽  
Author(s):  
Jiangquan Liu ◽  
Xiaoguang Ying ◽  
Hongxun Wang ◽  
Xiao Li ◽  
Weiying Zhang

Author(s):  
Konstantinos Kourelis ◽  
Konstantinos Mourtzouchos ◽  
Vasileios Haronis ◽  
Anastasios Goulioumis ◽  
Athanasios Asimakopoulos

2020 ◽  
Vol 143 ◽  
pp. 235-242 ◽  
Author(s):  
Minghao Zhang ◽  
Shiyan Chen ◽  
Li Zhong ◽  
Baoxiu Wang ◽  
Huaping Wang ◽  
...  

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Xinyue Zhu ◽  
Yifeng Shen ◽  
Zixiang Liu ◽  
Peiliang Gu ◽  
Shiliang Li ◽  
...  

Objective. This study aims to determine the methods of percutaneous release procedures in the lumbar ligamentum flavum (LF) under ultrasound guidance by acupotomy and provide an anatomical basis for intrusive treatment of lumbar disc herniation and lumbar spinal canal stenosis. Methods. Twelve cadavers including 4 females and 8 males aged 60 to 90 years (73.42 ± 14.57 years), without formalin fixation, were selected. Guided by an ultrasound transducer, we punctured acupotomy to release lumbar LF in L3/L4, L4/L5, and L5/S1 segments. In the transverse-axis approach, the probe was placed transversely, while in the longitudinal-axis approach, the probe was placed longitudinally. The depth of needle penetration (A), the distance between the puncture point and spinous process (B), and the distance between the puncture point and sacral cornu (C) were measured on cadavers, and the depth of needle penetration (U-A), the distance between the puncture point and spinous process (U-B), and the angle for acupotomy (D) on ultrasound images were also measured. Statistical analyses were carried out using SPSS. Paired sample t-tests and homogeneity of variance tests and one-way analysis of variance (ANOVA) were performed. The Pearson correlation coefficients and linear correlation coefficients were calculated for the data obtained from ultrasound and cadaver measurements. Results. No obvious blood vessels and nerves were observed in the puncture path, and the spinal dura was intact. There was no statistical difference between the left and right side measurements obtained from the ultrasound images and the cadavers. The penetration depth in the transverse-axis approach was less than that in the longitudinal-axis approach, and the angle of the needle in the transverse-axis approach was greater than that in the longitudinal-axis approach. The measured data for the transverse-axis approach for L3/L4, L4/L5, and L5/S1 segments showed that there were no differences in the needle angle, the depth of needle penetration, and the distance from the spinous process to the puncture point among the three segments. There was a strong correlation between the depth of needle penetration and the distance from the spinous process to the puncture point on the ultrasonic images and the cadavers on the path of acupotomy. Linear equation A = 2.02 + 0.83 ∗ U-A, R2 = 0.352; B = 1.37 + 0.71 ∗ U-B, R2 = 0.252, where A/B refers to the data measured on the cadavers and U-A/U-B refers to the data measured on the ultrasound images. Conclusion. In this study, ultrasound guidance was applied, which better guaranteed the safety and feasibility of acupotomy therapy. Before performing the treatment, the depth of needle penetration in the human body can be determined by measuring the distance between the needle point and the target position on the ultrasound image. Under ultrasound guidance, the transverse-axis approach has a smaller puncture depth and greater puncture angle than the longitudinal-axis approach. Hence, this study believes that the transverse-axis approach is safer for the clinical application of ultrasound-guided LF acupotomy lysis.


2017 ◽  
Vol 18 (5) ◽  
pp. 989 ◽  
Author(s):  
Luyuan Chen ◽  
Renze Shen ◽  
Satoshi Komasa ◽  
Yanxiang Xue ◽  
Bingyu Jin ◽  
...  

2011 ◽  
Vol 68 (9) ◽  
pp. 767-773 ◽  
Author(s):  
Zoran Andjelkovic ◽  
Snezana Kuzmic-Jankovic ◽  
Dragan Pucar ◽  
Ivan Tavcar ◽  
Tamara Dragovic

Background/Aim. According to the current principles, autonomous functional thyroid nodules are treated by surgery or by radioiodin therapy. Ultrasound guided percutaneous ethanol injection into solid tumors of the soft tissues was a starting point in attempts to treat the thyroid nodules by the same method. The aim of the study was to assess the efficiency of percutaneous injection in treating solitary, nontoxic, autonomous thyroid nodules of up to 15 mL volume. Methods. In 25 patients with solitary nontoxic autonomous thyroid nodules diagnosed by tehnetium-99m scanning as an intensive area having a complete supremacy in the paranodal tissue, an ultrasound guided percutaneous ethanol injection was applied. The procedure was carried out repeatedly once a week until the reduction in nodule size to 50% of the initial size was achieved. Results. An average size of the nodule before curing was 9.68 ? 5.01 mL. An average quantity of the injected ethanol was 9.52 ? 5.08 mL, ie 1.06 ? 0.48 mL/mg of the tissue. The regression of the nodule size in the successfully (?vol% u = - 57.09 ? 13.75%, p < 0.001) and partly successfully cured (?vol du = -48.45 ? 14.35%, p < 0.05) was statistically significant compared to the size before the treatment. After ceasing ethanol injection, 18 months later, a further size regression (?vol% = -79.20 ? 9.89%) compared to the initial one (p < 0.001) was noticed. Soon, after the procedure was finished, a statistically significant concentration increase of Thyroid Stimulating Hormone (TSH) was noticed compared to the initial values (0.18 ? 0.16 vs 0.34 ? 0.31 mU/L, p < 0.01). According to the given criteria, in two female patients satisfactory results were not achieved, but, a year later, in one of them the nodule was not seen by repeated scintigram. The number and frequency of side effects were insignificant. Conclusion. Repeated percutaneous ethanol injections into nontoxic solitary autonomous thyroid nodules result in disappearing of authonomy. The regression of the nodule size of more than 50% compared to its initial volume, as well as the increase in concentration of TSH for more than 50% are the signs of a successful treatment.


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