UltrasoundUltrasound

History of UltrasoundHistory of Ultrasound

First introduced to medical world in First introduced to medical world in 1950s1950s

However, has its beginnings in the However, has its beginnings in the 1880s when Pierre Curie introduced 1880s when Pierre Curie introduced simple echo sounding methods.simple echo sounding methods.

This led to the discovery of SONAR -This led to the discovery of SONAR -(Sound Navigating and Ranging)(Sound Navigating and Ranging)

SONAR, the technique of sending SONAR, the technique of sending sound waves through the water and sound waves through the water and observing the returning echoes to observing the returning echoes to characterize submerged objects characterize submerged objects inspired early ultrasound inspired early ultrasound investigators.investigators.

Shortly after WWII, researchers in Shortly after WWII, researchers in Japan began to explore medical Japan began to explore medical diagnostic capabilities of ultrasound.diagnostic capabilities of ultrasound.

The US and Europe became aware of The US and Europe became aware of this new diagnostic technique in the this new diagnostic technique in the 1950s when Japan presented their 1950s when Japan presented their findings on the use of ultrasound to findings on the use of ultrasound to detect gallstones, breast masses, detect gallstones, breast masses, and tumors.and tumors.

US pioneers contributed many US pioneers contributed many innovations and important innovations and important discoveries to the field in the discoveries to the field in the following decades.following decades.

Early 1970sEarly 1970s Gray scale static images of internal Gray scale static images of internal

organsorgans

Mid 1970sMid 1970s Real-time imagingReal-time imaging

Early 1980sEarly 1980s Spectral DopplerSpectral Doppler Color DopplerColor Doppler

Also produced was a hand-held Also produced was a hand-held “contact” scanner for clinical use.“contact” scanner for clinical use.

In the 1980s, after all these In the 1980s, after all these innovations, ultrasound technique innovations, ultrasound technique was technologically more advanced was technologically more advanced than computers. Because of this, than computers. Because of this, Samuel H. Maslak developed the Samuel H. Maslak developed the 128-channel Computed Sonography 128-channel Computed Sonography platform. This allowed for black-and-platform. This allowed for black-and-white and color ultrasound images white and color ultrasound images with superior resolution and clarity.with superior resolution and clarity.

1996 – Acuson Corp. developed the 1996 – Acuson Corp. developed the Sequoia 512 system. Sequoia 512 system.

Although ultrasound is better known Although ultrasound is better known for its diagnostic capabilities, it was for its diagnostic capabilities, it was initially used for therapy rather than initially used for therapy rather than diagnosis.diagnosis.

In the 1940s, ultrasound was used to In the 1940s, ultrasound was used to perform services similar to that of perform services similar to that of radiation or chemotherapy now.radiation or chemotherapy now.

Ultrasonic waves emit heat that can Ultrasonic waves emit heat that can create disruptive effects on animal create disruptive effects on animal tissue and destroy malignant tissue.tissue and destroy malignant tissue.

Principles of Ultrasound:Principles of Ultrasound:

Its Its ComponentsComponents

OperationsOperations

ApplicationApplicationss

ComponentsComponents

Transducer ProbeTransducer Probe Transducer Pulse ControlsTransducer Pulse Controls CPUCPU DisplayDisplay Keyboard/CursorKeyboard/Cursor Disk Storage DeviceDisk Storage Device PrinterPrinter

Physics of UltrasoundPhysics of Ultrasound

Transducer ProbeTransducer Probe ‘‘Mouth and Ears’ of the machine.Mouth and Ears’ of the machine. Piezoelectric EffectPiezoelectric Effect

Discovered by Pierre and Jacques CurieDiscovered by Pierre and Jacques Curie Application of electric currents changes the Application of electric currents changes the

shape of the crystals, which in turn shape of the crystals, which in turn propagate sound waves. propagate sound waves.

Receipt of sound waves changes shape of Receipt of sound waves changes shape of crystals again, which emit electrical signals.crystals again, which emit electrical signals.

Uses of UltrasoundUses of Ultrasound

Detection of tumors (Oncology).Detection of tumors (Oncology). Assesment of the development of Assesment of the development of

fetus (OB/GYN).fetus (OB/GYN). Evaluation of blood flow (Cardiology).Evaluation of blood flow (Cardiology). Insertions.Insertions.

Ultrasound in Obstetrics Ultrasound in Obstetrics and Gynecologyand Gynecology

Ultrasound is extensively used in Ultrasound is extensively used in obstetrics and gynecology as a safe, obstetrics and gynecology as a safe, non-invasive, accurate, and cost non-invasive, accurate, and cost effective tool to look at the fetus. effective tool to look at the fetus.

No set number of scans, but No set number of scans, but recommended that normally the recommended that normally the woman have 2 to 3.woman have 2 to 3.

11stst scan at 7 weeks: confirm pregnancy, scan at 7 weeks: confirm pregnancy, exclude ectopic or molar pregnancies, exclude ectopic or molar pregnancies, confirm cardiac pulsation, and measure confirm cardiac pulsation, and measure the crown-rump length for datingthe crown-rump length for dating

22ndnd scan at 18-20 weeks: look for scan at 18-20 weeks: look for congenital malformations, exclude congenital malformations, exclude multiple pregnancies, verify dates and multiple pregnancies, verify dates and growth, placental position (growth, placental position (or at 13-14 weeks or at 13-14 weeks to diagnose Down Syndrome).to diagnose Down Syndrome).

33rdrd scan at 34 weeks: evaluate fetal scan at 34 weeks: evaluate fetal size and assess fetal growth, verify size and assess fetal growth, verify fetal positionfetal position

TechniqueTechnique

The womanThe woman’’s abdomen is covered with a gel so s abdomen is covered with a gel so that the transducer can see through the skin that the transducer can see through the skin

real- time scanners (frequency sound waves real- time scanners (frequency sound waves between 3.5 and 7.0 megahertz) can give a between 3.5 and 7.0 megahertz) can give a continuous picture of the moving fetus continuous picture of the moving fetus

The transducer is placed in contact with the The transducer is placed in contact with the abdomen and moved about to look at different abdomen and moved about to look at different parts of the uterus. Several ultrasound beams parts of the uterus. Several ultrasound beams scan the fetus in thin slices, which are scan the fetus in thin slices, which are recomposed into a picture on the monitor recomposed into a picture on the monitor screen screen

What ultrasound detectsWhat ultrasound detects

verify intrauterine implantation to verify intrauterine implantation to exclude ectopic pregnancy, to exclude ectopic pregnancy, to diagnose a missed abortion, to diagnose a missed abortion, to establish gestation age and due establish gestation age and due date, and determine if there are date, and determine if there are multiple embryos multiple embryos

First trimester markers for First trimester markers for chromosomal abnormalities are used chromosomal abnormalities are used to detect Down syndrome to detect Down syndrome

Hydrocephalus, anencephaly, Hydrocephalus, anencephaly, myelomeningocoele, dwarfism, spina myelomeningocoele, dwarfism, spina befida, exomphalos, gastroschisis, befida, exomphalos, gastroschisis, duodenal atresia, and fetal hydrops duodenal atresia, and fetal hydrops can be diagnosed before 20 weeks can be diagnosed before 20 weeks

four and a half weeks the gestational sac four and a half weeks the gestational sac can be visualized, by five weeks the yolk can be visualized, by five weeks the yolk sac, and by five and a half weeks the sac, and by five and a half weeks the embryo can be visualized and measured embryo can be visualized and measured

Doppler ultrasound can detect a visible Doppler ultrasound can detect a visible heart beat and blood flow in fetal blood heart beat and blood flow in fetal blood vessels by six to seven weeks vessels by six to seven weeks

crown-rump length measured 7 to 13 weeks crown-rump length measured 7 to 13 weeks and gives an accurate estimation of and gives an accurate estimation of gestational age, biparietal diameter, the gestational age, biparietal diameter, the diameter of the head, measured after 13 diameter of the head, measured after 13 weeks, femur length at 14 weeksweeks, femur length at 14 weeks

cleft lips/ palate, spina bifida, cleft lips/ palate, spina bifida, polydactyl, low-set ears, facial polydactyl, low-set ears, facial dysmorphia, and clubbing of feet dysmorphia, and clubbing of feet

Ultrasound ToolsUltrasound Tools

Traditional 2-DTraditional 2-D 3-D3-D 4-D 4-D or dynamic 3-D scanners or dynamic 3-D scanners Transvaginal scanning Transvaginal scanning

ImagesImages

http://www.obgyn.net/us/us.asp?http://www.obgyn.net/us/us.asp?page=gallery/gallerypage=gallery/gallery

http://3dultrasound.ucsd.edu/gallery.htmlhttp://3dultrasound.ucsd.edu/gallery.html

http://www.ob-ultrasound.net/http://www.ob-ultrasound.net/goodwork.htmlgoodwork.html

Safety and RisksSafety and Risks

Unlike X-rays, ultrasound involves Unlike X-rays, ultrasound involves only sound wavesonly sound waves No radiation dangerNo radiation danger

However, sound waves can increase However, sound waves can increase body temperaturebody temperature This is known as cavitationThis is known as cavitation Significant only for long exposure timeSignificant only for long exposure time

Many studies have been Many studies have been conducted to determine conducted to determine the physiological effects the physiological effects of ultrasound cavitationof ultrasound cavitation

No direct correlation has No direct correlation has been found between been found between ultrasound imaging and ultrasound imaging and cancer, low birth weight, cancer, low birth weight, dyslexia or delayed dyslexia or delayed speech developmentspeech development

Reliable data from Reliable data from ultrasound techniques is ultrasound techniques is hard to come byhard to come by

Additional studies are Additional studies are ongoingongoing

Biggest risk is Biggest risk is misdiagnosismisdiagnosis

Future of UltrasoundFuture of Ultrasound

Improved clarity for Improved clarity for use in cancer diagnosisuse in cancer diagnosis

Increased therapeutic Increased therapeutic use to correct blood use to correct blood clots and kidney clots and kidney stonesstones

Portability and Portability and veterinary useveterinary use

Joint and muscle Joint and muscle treatment through treatment through cavitationcavitation