• 대한방사선기술학회지:방사선기술과학
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• 제14권2호
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• pp.37-44
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• 1991

The combined effect of radiation and ultrasound has been studied in mouse embryos. Radiation and/or ultrasound were adminstered to ICR mice on day 8 of gestation. Intrauterine death, gross malformation, and fetal body weight were selected as indicators of effects. Does of whole-body ${\gamma}-irradiation$ were 0.5 to 2.5 Gy and those of ultrasound were $0.5\;W/cm^2$ to $3\;W/cm^2$. Intrautrine mortality increased with increasing radiation dose ; this trend was more remarkable in combination with ultrasound. Gross malformations such as exencephaly and anophthalmia/microphthalmia appeared frequently in the fetuses treated with both radiation and ultrasound. Decreased fetal weight was observed even in mice treated with 1.5 Gy of radiation or $1\;W/cm^2$ of ultrasound. There was a linear relationship between dose and reduction of fetal weight. The fetal weight was sensitive, precise and easy-to-handle indicator for the effects of growth retardation. Intrauterine mortality and frequencies of exencephaly and anophthalmia/microphthalmia were higher than the sum of those induced by radiation and by ultrasound. The results indicatied that the combined action of radiation and ultrasound on intrauterine death and malformations was synergistic.

• The Journal of the Acoustical Society of Korea
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• 제28권1E호
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• pp.1-8
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• 2009

Primary radiation force on ultrasound contrast agents (UCA) in a propagating and standing acoustic field was explored. A specific ultrasound contrast agent $Albunex^{(R)}$ and $Optison^{(R)}$ were chosen for simulation. The model was developed based on a shelled bubble model proposed by Church. The numerical simulation suggests that bubble translational motion is more significant in therapeutic ultrasound due to higher intensity and long pulse duration. Even a single cycle of a propagating wave of 4 MPa at 1 MHz can cause a bubble translational motion of greater than $1{\mu}m$ which is approximately one tenth of capillary. Hence, UCA characteristics can be significantly changed in therapeutic ultrasound without rapid bubble collapses.

• 대한정형외과 초음파학회지
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• 제6권2호
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• pp.81-93
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• 2013

본 종설에서는 요추부 중재술에 있어서 초음파라는 장비가 영상 장치로서 얼마나 유용한가에 대해 기술하였다. 우선 요천추부의 표면 해부학과 초음파 해부학에 대하여 기술하였는데, 이는 초음파 유도하 중재술에서 영상의 판독과 술기의 수행에 있어 해부학의 자세한 이해가 반드시 필요하기 때문이다. 방사선 투시하에 척추 중재술을 하는 것이 보편화 되어 있지만 방사선을 피폭해야 하는 문제가 늘 존재한다. 초음파는 방사선이 없고 간편하며 높은 정확도로 실시간 영상을 제공하는 장점들이 있으며 어떠한 임상 환경적 조건에서도 시행할 수 있다. 초음파 유도하 요추부 중재술은 방사선 투시기나 컴퓨터 단층촬영 유도로 시행하였던 기존의 방식을 대신할 수 있으며 방사선 피폭 없이 안전하게 시행할 수 있는 방법이다.

• 대한의용생체공학회:의공학회지
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• 제32권3호
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• pp.264-269
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• 2011

To increase therapeutic efficiency and biological safety, it is important to precision control of acoustic output for therapeutic ultrasound equipment. In this paper, the electro-acoustic radiation conductance, one of electroacoustic characteristics of therapeutic ultrasound equipment, was measured by the radiation force balance method according to IEC 61161 standards and the acoustic output was estimated using the electro-acoustic radiation conductance. The estimation of acoustic output was conducted to continuous wave mode and pulse wave mode of duty cycle between 20% and 80%. The differences between prediction values and measurement results are within 5% of measurement uncertainty, which is a reasonably good agreement. The results show that acoustic output controlled by electro-acoustic radiation conductance was found to be an effective method.

• 한국음향학회지
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• 제38권4호
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• pp.467-475
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• 2019

고출력의 초음파는 매질을 진행하면 음향 흐름과 음향 방사힘을 만들어낸다. 공기를 매질로 하는 3차원 공간상에 음향 방사힘을 발생시키면 입체적인 촉감을 형성할 수 있으므로 공간적인 정보를 직접 피부에 촉각으로 전달할 수 있다. 본 논문은 40 kHz의 작은 초음파 송신자 154개를 묶어 오목한 형태로 배열시켜서 초음파를 송신하여 집속초점에서 음향 방사힘을 발생시켰다. 초음파 음장의 초점의 근처에서 음향 방사힘에 의한 촉각을 확인하였다. 촉각 감도를 올리기 위하여 송신 초음파를 60 Hz의 구형파로 진폭 변조를 하였다. 초음파 촉각의 응용으로 음향 방사힘이 형성되는 허공에 촉각이 감지되는 영역을 형성시켜서, 손의 위치를 지정하는 지시자로 사용하였다. 촉각이 감지되는 초점위치에 있는 손의 모양을 영상 입력으로 받아서 손가락의 개수를 기계에 피드백하는 시스템을 구현함으로써 초음파를 이용한 촉각의 유용성을 확인하였다.

• Radiation Oncology Journal
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• 제31권1호
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• pp.41-47
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• 2013

Purpose: To describe the early experience of analyzing variations and time trends in bladder volume of the rectal cancer patients who received bladder ultrasound scan. Materials and Methods: We identified 20 consecutive rectal cancer patients who received whole pelvic radiotherapy (RT) and bladder ultrasound scan between February and April 2012. Before simulation and during the entire course of treatment, patients were scanned with portable automated ultrasonic bladder scanner, 5 times consecutively, and the median value was reported. Then a radiation oncologist contoured the bladder inner wall shown on simulation computed tomography (CT) and calculated its volume. Results: Before simulation, the median bladder volume measured using simulation CT and bladder ultrasound scan was 427 mL (range, 74 to 1,172 mL) and 417 mL (range, 147 to 1,245 mL), respectively. There was strong linear correlation (R = 0.93, p < 0.001) between the two results. During the course of treatment, there were wide variations in the bladder volume and every time, measurements were below the baseline with statistical significance (12/16). At 6 weeks after RT, the median volume was reduced by 59.3% to 175 mL. Compared to the baseline, bladder volume was reduced by 38% or 161 mL on average every week for 6 weeks. Conclusion: To our knowledge, this study is the first to prove that there are bladder volume variations and a reduction in bladder volume in rectal cancer patients. Moreover, our results will serve as the basis for implementation of bladder training to patients receiving RT with full bladder.

• The Korean Journal of Pain
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• 제22권2호
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• pp.186-190
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• 2009

Sciatic nerve block is frequently used for anesthesia or analgesia during lower leg surgery or chronic lower leg pain syndrome. Recently, a lot of ultrasound-guided peripheral nerve block has been reported because there are several benefits compared to blind technique. We performed ultrasound-guided right sciatic nerve block successfully to the patient who has been suffering from right buttock pain after previous radiation therapy.

• Journal of Radiation Protection and Research
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• 제24권1호
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• pp.23-30
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• 1999

태생 8일째인 임신한 생쥐에 137-Cs 감마선과 초음파를 조사하였다. 복합조사의 경우 임신한 생쥐는 1.5 Gy 방사선과 $1.0W/cm^2$ 초음파로 -1, 0, 1, 3, 6 시간 간격으로 조사하였다. 사망과 외부 기형은 태생 18일에 검진하였다. 방사선에 의한 태생 8일의 사망 임계값은 0.5에서 1.0 Gy사이였으며, 초음파는 1.0에서 $1.5W/cm^2$ 사이였다. 태생 후반기의 사망은 방사선과 초음파의 복합 치료에 의해 상승적으로 증가되었다. 방사선에 의한 뇌탈출기형 및 무안구증의 임계값은 각각 0.5에서 1.0Gy사이와 1.0에서 1.5Gy 사이였다 초음파에 의한 뇌탈출기형과 무안구증의 임계값은 각각 1.0에서 $1.5W/cm^2$ 사이와 $1.5W/cm^2$ 이상이었다. 복합치료의 경우는 뇌 탈출기형과 무안구증의 빈도가 상승적으로 증가하였다. 한 시간 간격으로 두 가지 치료를 받은 생쥐에서 뇌 탈출기형과 무안구증의 빈도가 최고치에 도달하였다.

• Radiation Oncology Journal
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• 제6권1호
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• pp.75-80
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• 1988

Twenty seven lesions of 25 patients with locally advanced malignant tumors were treated with combined hyperthermia introduced by microwave and ultrasound and radiotherapy. Most of all patients were failed with previous conventional therapeutic trial. Hyperthermia had been done immediately after radiotherapy, twice a week, $43^{\circ}C$ for one hour and radiotherapy had been done 5 fractions per week with fraction size of 2Gy upto 30 to 60Gy. Conclusions are as follows. 1. Total response rate (PR+PR) to thermoradiotherapy with microwave and ultrasound was $81\%$. 2. Tumor depth, minimum temperature of tumor center, number of heat fraction and radiation dose were statistically significant factors affecting response. 3. Hyperthermia with microwave and ultrasound can be used efficiently to control locally advanced malignant disease whether previously received near tolerance dose of radiotherapy or not.

• Clinical Pain
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• 제20권2호
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• pp.93-98
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• 2021

The use of ultrasonography has recently been increasing in musculoskeletal diagnosis or intervention treatment. Ultrasound guided procedure offers a reliable alternative to fluoroscopy or computed tomography for lumbar medial branch block, facet joint block and peripheral nerves of lower extremity. Further, there is no exposure to radiation and additional equipment necessary for the protection against radiation is required. And ultrasound guided procedure needs smaller space than fluoroscopy guided procedure with real time images in the outpatient department. This article reviews ultrasound guided procedure at lumbar vertebra and peripheral nerves of lower extremity.