Spontaneous regression of lymphovascular invasion and metastasis of malignant melanoma: ultrasound findings.

This report presents a case of malignant melanoma in a 40-year-old male who underwent resection of the tumor in his right ankle. Eleven months after the resection, a subcutaneous mass was observed on his right femur. Ultrasound examination revealed a hypoechoic tubular structure in the right thigh, with a small amount of blood flow in the lesion. Using ultrasound and fine-needle aspiration, the patient was diagnosed with metastasis and lymphovascular invasion of malignant melanoma. Treatment with an immune checkpoint inhibitor was originally scheduled, but the lesion disappeared spontaneously after the fine-needle aspiration.

Assessment of the risk of disease transmission during fine-needle aspiration cytology under ultrasound guidance by visualization of droplet and aerosol formation.

PURPOSE: Fine-needle aspiration cytology (FNAC) under ultrasound guidance is clinically useful, but there is a risk of spreading infection by generating droplets of contaminated fluids during the procedure. Risk assessment to better control infection remains to be established. The aim of this study was to estimate infection risks during FNAC by visualization of droplet production and deposition using a simulation model. METHODS: The simulation comprised a puncture needle, a device for holding the needle, and a fluid specimen containing fluorescent particles as a model. Simulating each step of FNAC (removal of the inner and outer cylinder and transferring the specimen onto a glass slide), the generation and deposition of droplets were visualized using a laser. RESULTS: After removal of the inner cylinder, an aerosol of droplets in the air surrounding the needle was observed. After removal of the outer cylinder, several large droplets precipitating onto the circumjacent surface were observed. From the beginning of transferring the specimen, a large amount of sizeable droplets first moving away and then precipitating was observed, followed by the production of a cluster of fine droplets drifting and spreading through the air. CONCLUSIONS: Here, the generation of droplets at each step of FNAC, precipitation of large droplets onto the circumjacent surface, and drifting and spreading through the air of fine droplets was visualized. These results emphasize the need for precautions to prevent the transmission of infectious agents during FNAC.

Self-learning followed by telepresence instruction of focused cardiac ultrasound with a handheld device for medical students: a preliminary study.

PURPOSE: This study aimed to assess the feasibility and efficiency of self-learning with or without self-training (subjects performed scans on themselves) and telepresence instruction in focused cardiac ultrasound (FOCUS) education for medical students. METHODS: This study included 24 medical students. The participants initially completed a written pre-test and were randomized into a video lecture (participants watched a video lecture) or self-training (participants watched a video lecture and self-performed FOCUS) group. After finishing self-learning, they completed a written post-test. Then they undertook a skill pre-test and a first perception survey. Telepresence instruction was then provided. Finally, they undertook a skill post-test and a second perception survey. RESULTS: The written post-test total scores were significantly higher than the pre-test total scores (P < 0.001). In the skill pre-test, the scores for the video lecture and self-training groups were not significantly different (P = 0.542). The skill post-test total scores were significantly higher than the skill pre-test total scores (P = 0.008). Forty-two percent of the video lecture group participants agreed that the video lecture was effective preparation for the skill pre-test, while all participants in the same group agreed that the combination of the video lecture and telepresence instruction was effective preparation for the skill post-test. CONCLUSION: This study demonstrated the feasibility and efficiency of self-learning followed by telepresence instruction on FOCUS for medical students.

Ultrasonography in undergraduate medical education: a comprehensive review and the education program implemented at Jichi Medical University.

The concept of point-of-care ultrasound has been widely accepted owing to the development of portable ultrasound systems and growing body of evidence concerning its extensive utility. Thus, it is reasonable to suggest that training to use this modality be included in undergraduate medical education. Training in ultrasonography helps medical students learn basic subjects such as anatomy and physiology, improve their physical examination skills, and acquire diagnostic and procedural skills. Technological advances such as simulators, affordable handheld devices, and tele-ultrasound systems can facilitate undergraduate ultrasound education. Several reports have indicated that some medical schools have integrated ultrasound training into their undergraduate medical curricula. Jichi Medical University in Japan has been providing medical students with ultrasound education to fulfill part of its mission to provide medical care to rural areas. Vertical integration of ultrasound education into a curriculum seems reasonable to ensure skill retention and improvement. However, several issues have hampered the integration of ultrasound into medical education, including a lack of trained faculty, the need to recruit human models, requisition of ultrasound machines for training, and limited curricular space; proposed solutions include peer teaching, students as trained simulated patients, the development of more affordable handheld devices, and a flipped classroom approach with access to an e-learning platform, respectively. A curriculum should be developed through multidisciplinary and bottom-up student-initiated approaches. Formulating national and international consensuses concerning the milestones and curricula can promote the incorporation of ultrasound training into undergraduate medical education at the national level.

Inhibitory effects of ultrasound irradiation on Staphylococcus epidermidis biofilm.

PURPOSE: We aimed to investigate whether low-intensity continuous and pulsed wave ultrasound (US) irradiation can inhibit the formation of Staphylococcus epidermidis biofilms, for potential application in the treatment of catheter-related bloodstream infections (CRBSI). METHODS: S. epidermidis biofilms that formed on the bottom surfaces of 6-well plates were irradiated on the bottom surface using the sound cell incubator system for different intervals of time. RESULTS: US irradiation with continuous waves for 24 h notably inhibited biofilm formation (p < 0.01), but the same US irradiation for 12 h had no remarkable effect. Further, double US irradiation with pulsed waves for 20 min inhibited biofilm formation by 33.6%, nearly two-fold more than single US irradiation, which reduced it by 17.9%. CONCLUSION: US irradiation of a lower intensity (ISATA = 6-29 mW/cm2) than used in a previous study and lower than recommended by the Food and Drug Administration shows potential for preventing CRBSI caused by bacterial biofilms.

Effect of ultrasonic irradiation on bacterial biofilms.

PURPOSE: The purpose of this study was to clarify the effect of ultrasonic irradiation on biofilm produced by Staphylococcus epidermidis (S. epidermidis), which causes central venous catheter-related infections. MATERIALS AND METHODS: Staphylococcus epidermidis (S. epidermidis, ATCC 35984 RP 62A) was used in this study. First, biofilm was prepared from S. epidermidis on the bottom of the upper left well of a 6-well plate. Next, the biofilm was irradiated for 24 h with 1-MHz ultrasound (US) in the continuous wave mode to serve as the US irradiation group. The acoustic power irradiated below the bottom of the well was 3.8 mW. As a control (non-US irradiation group), non-irradiated biofilm on the bottom of a 6-well plate was incubated at 37 °C in an atmosphere of 5.0% CO2. After US irradiation, the bottoms of the wells were stained with 0.1% crystal violet for 60 s. To extract the crystal violet, 99.5% ethanol was added to the wells, and the extracted solutions were measured at an absorbance of 595 nm. RESULT: The absorbance of the US irradiation group was significantly less than that of the non-US irradiation group (p < 0.01). CONCLUSION: US irradiation can decrease the amount of S. epidermidis biofilm when the duration of US irradiation is sufficiently long even if the acoustic intensity is low.

Incidence of human papillomavirus contamination of transvaginal probes in Japan and possible contamination prevention strategy.

PURPOSE: To clarify the present status of human papillomavirus (HPV) contamination of transvaginal probes in Japan and propose a preventive method. METHODS: This study was performed at three institutes: a tertiary center, secondary hospital, and primary facility. To identify contamination rates, probes were disinfected and covered with probe covers and condoms; the cover was changed for each patient. The probes were tested for HPV, and those with HPV detected were analyzed to identify the type of HPV. Next, nurses put on new gloves before covering the probe for each patient, and the probes were similarly tested for HPV. RESULTS: A total of 120 probes were tested, and HPV was detected from a total of five probes, a contamination rate of 4.2 % (5/120). HPV was detected in all three institutes. Importantly, high-risk HPV, i.e., HPV-52, 56, and 59, was detected. After the "glove change strategy" was implemented, HPV was not detected on any of 150 probes tested at any of the three institutions. CONCLUSIONS: In Japan, the HPV contamination rate of vaginal probes in routine practice was 4.2 %. There was no HPV contamination of probes after changing the gloves for cover exchange for each patient. This strategy may prevent HPV probe contamination.

Endothelial dysfunction by flow-mediated dilation assessed ultrasonically in patients with Kawasaki Disease.

Kawasaki Disease (KD) is a febrile disorder seen in infants and young children. One of the most serious complications of the disease is coronary aneurysm. Endothelial dysfunction is considered to underlie the etiopathology of coronary aneurysm. Flow-mediated dilation (FMD), as assessed ultrasonically, is used to observe the endothelial function. The current paper summarizes, by providing a systematic review, the clinical studies that have examined endothelial dysfunction by determining the FMD ultrasonically in patients with KD. A PubMed-based search found eight articles published until 2013. Six studies reported the FMD level to be significantly lower in the patients with KD compared to controls, while two studies reported no significant difference in the FMD level between those with and without KD. Although patients with KD appeared to have endothelial dysfunction in the current summary, most reports have been associated with limitations, such as a small size and no prospective design for vascular outcomes. Further studies are therefore needed to draw definite conclusions regarding whether patients with KD suffer from endothelial dysfunction as determined by the FMD and/or whether this determination can be useful for understanding and managing vascular complications in these patients.

[The Accurate Quantification of Monoclonal Immunoglobulin by A Capillary Electrophoresis System].

The amount of monoclonal immunoglobulin (M protein) distinguishes multiple myeloma (M) from mono- clonal gammopathy of undetermined significance (MGUS) and indicates the effectiveness of treatment for MM. It should be calculated by serum total protein (g/dL) and M peak ratio (%) on the densitometry of se- rum electrophoresis. However, the ordinary method possibly overestimates the amount of M protein, be- cause this method utilizes the area from the baseline of the M peak (baseline method). For the more accu- rate measurement of M protein, in this study, we evaluated a capillary electrophoresis system that enables to extract the proper area of M peak by manual operation (peak method). Three serum samples with positive M protein were mixed with M protein negative serum at various ratio, and the measured values of M protein were compared with the theoretical values for both baseline and peak methods. All the results showed that the peak method gave the values close to the theoretical values compared with the baseline method. Espe- cially, the less M protein positive serum was mixed, the further the values by the baseline method parted from the theoretical one. In conclusion, the peak method using a capillary electrophoresis system should be introduced for the accurate quantification of M protein. [Original].

Coexistence of papillary thyroid cancer and Hashimoto thyroiditis in children: report of 3 cases.

This report documents 3 pediatric papillary thyroid carcinoma cases with associated Hashimoto thyroiditis. In all 3 cases, hypoechoic nodules accompanied by multiple echogenic spots were noted on sonography of the thyroid. Hashimoto thyroiditis was suspected on the basis of positive thyroid autoantibody test results and pathologic examinations of thyroidectomy specimens, which revealed chronic thyroiditis with lymphocytic infiltration as the background of papillary thyroid carcinoma development. The potential for papillary carcinoma development warrants close follow-up, and meticulous sonographic examinations must be performed in children with Hashimoto thyroiditis.

Ultrasound probes as a possible vector of bacterial transmission.

Ultrasound probes are usually in a direct contact with the skin when used for detecting pathologic abnormalities. The probe could be a vector of bacterial transmission, but there have been few studies on this topic.We have made such studies, briefly reviewing 1)the conditions governing a possible bacterial transmission by probe, 2) the deterioration of an ultrasound probe by alcohol disinfection, 3) a suitable method for evaluating bacterial contamination of an ultrasound probe, and 4) the best procedure for decontaminating such probes. This paper ,may lead to a formal consideration of the relationship between ultrasound probes and their roles in bacterial transmission in clinical practice.

The effectiveness of "Protex" for disinfection of the ultrasound probe.

The aim of this study was to evaluate the effectiveness of "Protex" (Parker; Fairfield, NJ, USA) for disinfection of ultrasound probes. We examined bacterial contamination on ultrasound probes that were wiped with a plain paper towel, with a plain and an ethanol-soaked paper towel, or with a plain and Protex-soaked paper towel. The plain paper towel was used to remove the gel, and was contaminated by large numbers of bacteria, but the use of ethanol-soaked paper towels and that of paper towels soaked in Protex™ broad-spectrum disinfectant (Parker: Fairfield, NJ, USA) reduced those numbers markedly.

Evaluation of procedures for decontaminating ultrasound probes.

PURPOSE: To determine suitable procedures for decontaminating ultrasound probes. METHODS: We investigated bacterial transmission via ultrasound probes that were not wiped, wiped with a plain paper towel, or wiped with an ethanol-soaked paper towel. RESULTS: The unwiped probes transmitted large numbers of bacteria, which were markedly reduced by wiping the probes with a plain paper towel, and almost completely eliminated by wiping with an ethanol-soaked paper towel. CONCLUSION: Improperly decontaminated ultrasound probes can transmit bacteria among patients. Ultrasound probes should be decontaminated by wiping with a paper towel after examinations to prevent bacterial transmission. Plain or ethanol-soaked paper towels should be used depending on the situation.

Sonographic findings of Sister Mary Joseph's nodule from ovarian cancer.

Sister Mary Joseph's nodule (SMJN), which is known as a malignant tumor metastasized to the umbilicus, is a rare condition. We report ultrasonic findings of SMJN secondary to ovarian cancer in a 66-year-old woman. The umbilical tumor was observed as a hypoechoic mass with punctate hyperechoic foci. A pathological specimen obtained by needle biopsy confirmed adenocarcinoma with psammoma bodies. A comparison of the ultrasonographic findings with the pathological findings of the resected specimen suggested that the hyperechoic foci corresponded to psammoma bodies. When hyperechoic foci are observed inside SMJN by ultrasonography, adenocarcinoma from ovarian cancer should be included in the differential diagnosis.

Degradation of ultrasound probes caused by disinfection with alcohol.

The aim of this study was to clarify the degree of degradation of ultrasonic probes that results from their disinfection with alcohol. No defect in the ultrasound beams was found in any of the probes, but a significant decrease of the brightness was found after a certain period of use of the linear-type probe. Disinfection with alcohol may degrade ultrasound probes despite its high degree of effectiveness in preventing iatrogenic bacterial transmission.