scholarly journals Output intensity measurement on a diagnostic ultrasound machine using a calibrated thermoacoustic sensor

2004 ◽  
Vol 1 ◽  
pp. 140-145 ◽  
Author(s):  
Volker Wilkens ◽  
Hans-Peter Reimann
Keyword(s):  
Diagnostic Ultrasound ◽  
Intensity Measurement ◽  
Output Intensity ◽  
Ultrasound Machine

scholarly journals Diagnostic Ultrasound Safety

2014 ◽  
Vol 8 (2) ◽  
pp. 178-183 ◽  
Author(s):  
Kazuo Maeda
Keyword(s):  
Obstet Gynecol ◽  
Physical Property ◽  
Diagnostic Ultrasound ◽  
Mechanical Effect ◽  
Mechanical Index ◽  
Pulsed Doppler ◽  
Output Intensity ◽  
Thermal Index ◽  
4D Ultrasound ◽  
Pulsed Doppler Ultrasound

ABSTRACT Ultrasound bioeffect is discussed from its physical property, i.e. thermal effect by thermal index, mechanical effect by mechanical index, and by the output intensity of ultrasound. Generally, thermal and mechanical indices should be lower than 1 in obstetrical setting, and threshold output intensity of no bioeffect is lower than SPTA 240 mW/cm2 in pulse wave. Pulsed Doppler ultrasound thermal and mechanical indices should be also lower than 1, and should be carefully used it in 11 to 13+6 weeks of pregnancy. Real-time B-mode, transvaginal scan, pulsed Doppler, 3D and 4D ultrasound were separately discussed in the ultrasound safety. Generally diagnostic ultrasound is safe for the fetus and embryo, if thermal and mechanical indices are lower than 1, and ultrasound devices are safe, if it is used under official limitation, e.g. the output intensity is less than SPTA 10 mW/cm2 in Japan. The ultrasound user is responsible ultrasound safety, e.g. higher thermal and mechanical indices than 1 should be lowered to be lower than 1, controlling the device output intensity. The user should learn bioeffects of ultrasound and prudent use of ultrasound under the ALARA principle. How to cite this article Maeda K, Kurjak A. Diagnostic Ultrasound Safety. Donald School J Ultrasound Obstet Gynecol 2014;8(2):178-183.

The early development of diagnostic ultrasound in Denmark

2011 ◽  
Author(s):  
Jørgen Jørgensen
Keyword(s):  
Diagnostic Ultrasound ◽  
County Hospital ◽  
Interventional Ultrasound ◽  
Senior Registrar ◽  
Ultrasound Machine ◽  
Ultrasound Studies ◽  
Surgical Department ◽  
Staff Members ◽  
Young Surgeon ◽  
The University

The development of diagnostic ultrasound in medicine began in Denmark in November 1965 at the Surgical Department H at Gentofte County Hospital in Copenhagen, and a prosperous time for diagnostic ultrasound began. It was the young surgeon Hans Henrik Holm who took the initiative, strongly supported by the head of the department Professor P.A. Gammelgaard. Hans Henrik Holm had for years studied ultrasound and earlier in 1965 he had visited Helmuth Hertz in Lund in Sweden to discuss the prospects of ultrasound. A grant from a national scientific foundation of 60 000 Danish kroner (approximately $10 000) made it possible to buy the American Physionic A-mode ultrasound machine. It was installed in a spare room at the Surgical Department H at Gentofte County Hospital in Copenhagen. An ultrasound laboratory was hereby established, and it was increasingly involved in a variety of clinical ultrasound studies and in the development and testing of new ultrasound equipment. The expenses were met by both the hospital and the University of Copenhagen, and a great deal of the research was financed by foundations. Hans Henrik Holm became the day-to-day head of the laboratory and he kept this position for many years. The Surgical Department and the ultrasound laboratory, designated the Ultrasound Department, were relocated to the new Herlev County Hospital in 1976 where Hans Henrik Holm became consultant at the Urology Department and Professor in Ultrasound and Interventional Ultrasound affiliated with the Surgical Department. The Ultrasound Department at Herlev had an increasing number of rooms and staff members. A senior registrar (Jø rgen Kvist Kristensen) was associated to the department in 1975 and Søren Torp-Pedersen was appointed consultant at the department in 1989. In 1966, 250 patients were examined annually. Thirty years later the Ultrasound Department at Herlev Hospital examined 17 000 patients annually, and ultrasound departments had been established at other hospitals in the Copenhagen area. By 1966 two papers in Danish were published and two papers in English were published in 1967 and 1968 . The number of staff rapidly increased, and a group of enthusiastic doctors and technicians was formed, working with patients and on scientific projects.

The right diagnostic ultrasound machine for you?

In Practice ◽  
1992 ◽  
Vol 14 (3) ◽  
pp. 142-144
Author(s):  
Frances Barr
Keyword(s):  
Diagnostic Ultrasound ◽  
Ultrasound Machine ◽  
The Right

scholarly journals Safety of Transvaginal Scan Estimated from Ultrasonic Bioeffects

2017 ◽  
Vol 11 (1) ◽  
pp. 1-6
Author(s):  
Kazuo Maeda
Keyword(s):  
Cell Growth ◽  
Negative Pressure ◽  
Fetal Tissue ◽  
Biological Tissues ◽  
Diagnostic Ultrasound ◽  
Ultrasound Wave ◽  
Mechanical Index ◽  
Output Intensity ◽  
Thermal Status ◽  
Excess Heating

ABSTRACT The embryo and fetus are generally studied using ultrasound imaging in pregnancy; however, ultrasound wave is absorbed by biological tissues to elevate the temperature. The growing embryonic and fetal tissue tends to be damaged by heating; thus, excess heating that damages young sensitive growing tissue should be prevented in ultrasound diagnosis. Hence, the thermal status of diagnostic ultrasound should be known with thermal index (TI), of which the determination and application are discussed in this chapter. Peculiar problem to transvaginal scan and thermal problem in febrile patient are discussed. Additionally, the cavitation, which is related with negative pressure, develops high pressure, high temperature, and free radicals that damage embryonic and fetal tissues. Therefore, the mechanical index (MI) has to be determined, measuring negative pressure of ultrasound. The MI is determined for the safety of diagnostic ultrasound. The ultrasound device output intensity that suppresses fetal amniotic JTC-3 cultured cell growth was determined, where 240 mW/cm2 or less output intensity did not suppress the cell growth, namely, the diagnostic ultrasound has no bioeffect when the output is lower than 240 mW/cm3. The as low as reasonably achievable principle in the Doppler method of 0.1 TI will be discussed. Three experimental reports of hazardous effects of ultrasound are discussed. How to cite this article Maeda K. Safety of Transvaginal Scan Estimated from Ultrasonic Bioeffects. Donald School J Ultrasound Obstet Gynecol 2017;11(1):1-6.

Maximum Output Intensity of the Audiokinetron

1996 ◽  
Vol 5 (2) ◽  
pp. 68-72 ◽  
Author(s):  
Christine M. Rankovic ◽  
William M. Rabinowitz ◽  
Gregory L. Lof
Keyword(s):  
Developmental Disabilities ◽  
Maximum Output ◽  
Output Intensity ◽  
Safety Studies ◽  
Auditory Integration Training ◽  
Auditory Integration

The Audiokinetron is a device that processes music for earphone presentation to patients undergoing auditory integration training, a treatment for individuals with autism and other developmental disabilities. Intensity levels produced by the Audiokinetron were measured under realistic listening conditions with a KEMAR manikin substituted for a patient. Average levels at the eardrum were 110 dB SPL when the device was adjusted to the highest setting employed by a local, trained AIT practitioner and 118 dB SPL at the maximum setting of the device. These levels are potentially harmful to hearing and warrant further safety studies of AIT instruments and protocols.

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