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释义 DictionarySeeultrasonographyMedicalSeeDOPPLER ULTRASONOGRAPHY: Doppler probe used on (A) dorsal pedis and (B) posterior tibial arteries

Doppler ultrasonography

The shift in frequency produced when an ultrasound wave is echoed from something in motion. The use of the Doppler effect permits measuring the velocity of that which is being studied, e.g., blood flow in a vessel. See: illustration

endobronchial ultrasonography

Abbreviation: EBUS
The fitting of a bronchoscope with an ultrasound transducer to identify masses adjacent to the bronchi. EBUS has been used to improve the diagnostic yield of transbronchial lung biopsies and needle aspiration in patients suspected of having lung cancer and sarcoidosis.

four-dimensional ultrasonography

An ultrasonic technique, often used during pregnancy, providing images of the fetus in three dimensions and in real time. Tthe technique is called four dimensional because there are three spatial variables plus time

gray-scale ultrasonography

Sonographic B-mode scanning that permits echoes to be displayed in shades of gray according to their amplitudes.

pelvic ultrasonography

Transvaginal ultrasonography.

three-dimensional ultrasonography

, three-dimensional ultrasound, 3D ultrasonography, 3D ultrasoundAn ultrasonic technique, often used during pregnancy, providing images of the fetus in three dimensions.

transrectal ultrasonography of the prostate

The use of an ultrasonic detection device placed in the rectum in order to guide biopsy of the prostate.

transvaginal ultrasonography

An ultrasonic examination of the uterus, fallopian tubes, endometrium, and, in pregnant patients, the fetus, by placing a transducer inside the vagina.

Patient care

It may be used to diagnose ectopic pregnancy, determine multiple pregnancies, locate the placenta, identify ovarian cysts and pelvic cancers, and visualize tubo-ovarian abscesses. The patient prepares for the ultrasound by removing her clothing from the waist down and dressing in a clean gown. She is helped into a supine position on an examination table, and her knees are placed in approx. 90° of flexion with her feet supported in stirrups. The ultrasound transducer is covered with a condom or sterile glove coated with a lubricant gel. The patient is told that the probe will be inserted into her vagina, and that the gel may feel cold and slippery. The probe is then directed toward the internal organs, from which sound wave (echo) images are obtained, usually painlessly and without ionizing radiation exposure.

Synonym: endovaginal ultrasound; pelvic ultrasonography

ultrasonography

The use of ultrasonic waves to image body structures for diagnostic purposes. See ULTRASOUND SCANNING.

Ultrasonography

A process that uses the reflection of high-frequency sound waves to make an image of structures deep within the body. Ultrasonography is routinely used to detect fetal abnormalities.Mentioned in: Ascites, Cholestasis, Eye Examination, Mental Retardation, Pelvic Ultrasound, Pyloric Stenosis, Splenic Trauma, Transient Ischemic Attack

ultrasonography 

A technique utilizing high frequency ultrasound waves (greater than 18 000 Hz) emitted by a transducer placed near the eye. The silicone probe, which rests on the eye, is separated from the transducer by a water column to segregate the noise from the transducer. The technique is used to make biometric measurements such as the axial length of the eye, the depth of the anterior chamber, the thickness of the lens, the distance between the back of the lens and the retina, the thickness of the cornea and detect ocular pathology. The ultrasound wave is reflected back when it encounters a change in density (or elasticity) of the medium through which it is passing. The reflected vibration is called an echo. Echoes from the interfaces between the various media of the eye are converted into an electrical potential by a piezoelectrical crystal and can be displayed as deflections or spikes on a cathode-ray oscilloscope.There are two basic techniques used for examination: a contact system (often referred to as applanation) described above in which the probe is in contact with cornea and an immersion system in which the transducer and the cornea are separated by a water bath. This latter method eliminates the risk of indentation of the cornea and underestimation of the anterior chamber depth and axial length. Two types of ultrasonographic measurements are used: (1) The time-amplitude or A-scan which measures the time or distance from the transducer to the interface and back. Thus echoes from surfaces deeper within the eye take longer to return to the transducer for conversion into electrical potential and so they appear further along the time base on the oscilloscope display. The A-scan is useful for the study of the biometric measurements, as well as measurements of intraocular tumour size (e.g. choroidal melanoma) (Fig. U1). (2) The intensity-modulated or B-scan in which various scans are taken through the pupillary area and any change in acoustic impedance is shown as a dot on the oscilloscope screen, and these join up as the transducer moves across a meridian. The B-scan is useful to indicate the position of a retinal or vitreous detachment, or of an intraocular foreign body or a tumour, and for the examination of the orbit. The B-scan is especially useful in the examination of the posterior structures of the eye when opacities prevent ophthalmoscopic examination (e.g. cataract, corneal oedema). Syn. echography. See biometry of the eye; axial length of the eye.enlarge picture" >Fig. U1 Histogram of ultrasound reflections (or echoes) in the eye. Echoes from the various boundaries are given against total time, i.e. the time interval from the cornea to the boundary and back to the cornea. The velocity of the ultrasound waves in the eye is approximately 1550 m/s (it is 1641 m/s in the lens and 1532 m/s in the humours). In the above diagram the total time between the cornea and the retina is 32 μs. The length is then equal to 32/2 ✕ 10 −6 ✕ 1550 ✕ 10 3 = 24enlarge pictureFig. U1 Histogram of ultrasound reflections (or echoes) in the eye. Echoes from the various boundaries are given against total time, i.e. the time interval from the cornea to the boundary and back to the cornea. The velocity of the ultrasound waves in the eye is approximately 1550 m/s (it is 1641 m/s in the lens and 1532 m/s in the humours). In the above diagram the total time between the cornea and the retina is 32 μs. The length is then equal to 32/2 ✕ 10−6 ✕ 1550 ✕ 103 = 24

ul·tra·so·nog·ra·phy

(ŭl'tră-sŏ-nog'ră-fē) The location, measurement, or delineation of deep structures by measuring the reflection or transmission of high-frequency or ultrasonic waves.
Synonym(s): echography, sonography.
[ultra- + L. sonus, sound, + G. graphō, to write]

Patient discussion about ultrasonography

Q. Do doctors normally do ultrasounds to prove you have mis carried?? 2 weeks ago i found out i was pregnant, i started spottion so we went to the hospital where they toldl me i miscarried, but they did not do any alternative tests to prove it not even check my Hcg levels. Im wandering if i should get a second opinion to make sure.A. Congratulations on the new pregnancy - that's wonderful news!

Q. what does it mean when an ultrasound shows an empty amniotic sac and no baby? A. This exact thing happened with my friend who is now 22 weeks with her first baby. She had 2 additional sacs - both empty - and the doctor said that the pregnancy had probably started out as triplets but that only one of the embryos had actually established and continued to grow.
Her doctor said it is very common for a woman to have more than one egg fertilize but that in most cases the pregnancy continues as a singleton only. She told my friend that the empty sacs would just disappear through time (which they did) and that they posed no danger to her baby.

Q. what kind of uses the medicine do with computers related to ultra sound? how does the computer helps the doctors in the ultra sound? what do the compuers use for? A. the computers help the doctors (in ultrasound cases) to interpret/convert the ultrasound waves into a specific imaging showed in the monitor. by that a doctor can find what is normal or not inside the patient's body.
for pregnancy purposes, it really helps patient in antenatal screening to find some abnormalities (if there's any) and to monitor the fetus' development along the 9-months pregnancy.
yesterday I wrote a short article about ultrasound update : http://doctoradhi.com/blog/?p=388

More discussions about ultrasonography
">ultrasonography posterior tibial arteries" href="javascript:eml2('davisTab', 'u04.jpg')">DOPPLER ULTRASONOGRAPHY: Doppler probe used on (A) dorsal pedis and (B) posterior tibial arteries

Doppler ultrasonography

The shift in frequency produced when an ultrasound wave is echoed from something in motion. The use of the Doppler effect permits measuring the velocity of that which is being studied, e.g., blood flow in a vessel. See: illustration

endobronchial ultrasonography

Abbreviation: EBUS
The fitting of a bronchoscope with an ultrasound transducer to identify masses adjacent to the bronchi. EBUS has been used to improve the diagnostic yield of transbronchial lung biopsies and needle aspiration in patients suspected of having lung cancer and sarcoidosis.

four-dimensional ultrasonography

An ultrasonic technique, often used during pregnancy, providing images of the fetus in three dimensions and in real time. Tthe technique is called four dimensional because there are three spatial variables plus time

gray-scale ultrasonography

Sonographic B-mode scanning that permits echoes to be displayed in shades of gray according to their amplitudes.

pelvic ultrasonography

Transvaginal ultrasonography.

three-dimensional ultrasonography

, three-dimensional ultrasound, 3D ultrasonography, 3D ultrasoundAn ultrasonic technique, often used during pregnancy, providing images of the fetus in three dimensions.

transrectal ultrasonography of the prostate

The use of an ultrasonic detection device placed in the rectum in order to guide biopsy of the prostate.

transvaginal ultrasonography

An ultrasonic examination of the uterus, fallopian tubes, endometrium, and, in pregnant patients, the fetus, by placing a transducer inside the vagina.

Patient care

It may be used to diagnose ectopic pregnancy, determine multiple pregnancies, locate the placenta, identify ovarian cysts and pelvic cancers, and visualize tubo-ovarian abscesses. The patient prepares for the ultrasound by removing her clothing from the waist down and dressing in a clean gown. She is helped into a supine position on an examination table, and her knees are placed in approx. 90° of flexion with her feet supported in stirrups. The ultrasound transducer is covered with a condom or sterile glove coated with a lubricant gel. The patient is told that the probe will be inserted into her vagina, and that the gel may feel cold and slippery. The probe is then directed toward the internal organs, from which sound wave (echo) images are obtained, usually painlessly and without ionizing radiation exposure.

Synonym: endovaginal ultrasound; pelvic ultrasonography

ultrasonography

The use of ultrasonic waves to image body structures for diagnostic purposes. See ULTRASOUND SCANNING.

Ultrasonography

A process that uses the reflection of high-frequency sound waves to make an image of structures deep within the body. Ultrasonography is routinely used to detect fetal abnormalities.Mentioned in: Ascites, Cholestasis, Eye Examination, Mental Retardation, Pelvic Ultrasound, Pyloric Stenosis, Splenic Trauma, Transient Ischemic Attack

ultrasonography 

A technique utilizing high frequency ultrasound waves (greater than 18 000 Hz) emitted by a transducer placed near the eye. The silicone probe, which rests on the eye, is separated from the transducer by a water column to segregate the noise from the transducer. The technique is used to make biometric measurements such as the axial length of the eye, the depth of the anterior chamber, the thickness of the lens, the distance between the back of the lens and the retina, the thickness of the cornea and detect ocular pathology. The ultrasound wave is reflected back when it encounters a change in density (or elasticity) of the medium through which it is passing. The reflected vibration is called an echo. Echoes from the interfaces between the various media of the eye are converted into an electrical potential by a piezoelectrical crystal and can be displayed as deflections or spikes on a cathode-ray oscilloscope.There are two basic techniques used for examination: a contact system (often referred to as applanation) described above in which the probe is in contact with cornea and an immersion system in which the transducer and the cornea are separated by a water bath. This latter method eliminates the risk of indentation of the cornea and underestimation of the anterior chamber depth and axial length. Two types of ultrasonographic measurements are used: (1) The time-amplitude or A-scan which measures the time or distance from the transducer to the interface and back. Thus echoes from surfaces deeper within the eye take longer to return to the transducer for conversion into electrical potential and so they appear further along the time base on the oscilloscope display. The A-scan is useful for the study of the biometric measurements, as well as measurements of intraocular tumour size (e.g. choroidal melanoma) (Fig. U1). (2) The intensity-modulated or B-scan in which various scans are taken through the pupillary area and any change in acoustic impedance is shown as a dot on the oscilloscope screen, and these join up as the transducer moves across a meridian. The B-scan is useful to indicate the position of a retinal or vitreous detachment, or of an intraocular foreign body or a tumour, and for the examination of the orbit. The B-scan is especially useful in the examination of the posterior structures of the eye when opacities prevent ophthalmoscopic examination (e.g. cataract, corneal oedema). Syn. echography. See biometry of the eye; axial length of the eye.enlarge picture" >Fig. U1 Histogram of ultrasound reflections (or echoes) in the eye. Echoes from the various boundaries are given against total time, i.e. the time interval from the cornea to the boundary and back to the cornea. The velocity of the ultrasound waves in the eye is approximately 1550 m/s (it is 1641 m/s in the lens and 1532 m/s in the humours). In the above diagram the total time between the cornea and the retina is 32 μs. The length is then equal to 32/2 ✕ 10 −6 ✕ 1550 ✕ 10 3 = 24enlarge pictureFig. U1 Histogram of ultrasound reflections (or echoes) in the eye. Echoes from the various boundaries are given against total time, i.e. the time interval from the cornea to the boundary and back to the cornea. The velocity of the ultrasound waves in the eye is approximately 1550 m/s (it is 1641 m/s in the lens and 1532 m/s in the humours). In the above diagram the total time between the cornea and the retina is 32 μs. The length is then equal to 32/2 ✕ 10−6 ✕ 1550 ✕ 103 = 24

ul·tra·so·nog·ra·phy

(ŭl'tră-sŏ-nog'ră-fē) The location, measurement, or delineation of deep structures by measuring the reflection or transmission of high-frequency or ultrasonic waves.
Synonym(s): echography, sonography.
[ultra- + L. sonus, sound, + G. graphō, to write]

Patient discussion about ultrasonography

Q. Do doctors normally do ultrasounds to prove you have mis carried?? 2 weeks ago i found out i was pregnant, i started spottion so we went to the hospital where they toldl me i miscarried, but they did not do any alternative tests to prove it not even check my Hcg levels. Im wandering if i should get a second opinion to make sure.A. Congratulations on the new pregnancy - that's wonderful news!

Q. what does it mean when an ultrasound shows an empty amniotic sac and no baby? A. This exact thing happened with my friend who is now 22 weeks with her first baby. She had 2 additional sacs - both empty - and the doctor said that the pregnancy had probably started out as triplets but that only one of the embryos had actually established and continued to grow.
Her doctor said it is very common for a woman to have more than one egg fertilize but that in most cases the pregnancy continues as a singleton only. She told my friend that the empty sacs would just disappear through time (which they did) and that they posed no danger to her baby.

Q. what kind of uses the medicine do with computers related to ultra sound? how does the computer helps the doctors in the ultra sound? what do the compuers use for? A. the computers help the doctors (in ultrasound cases) to interpret/convert the ultrasound waves into a specific imaging showed in the monitor. by that a doctor can find what is normal or not inside the patient's body.
for pregnancy purposes, it really helps patient in antenatal screening to find some abnormalities (if there's any) and to monitor the fetus' development along the 9-months pregnancy.
yesterday I wrote a short article about ultrasound update : http://doctoradhi.com/blog/?p=388

More discussions about ultrasonography
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