See biometry of the eye axial length of the eye. The B-scan is especially useful in the examination of the posterior structures of the eye when opacities prevent ophthalmoscopic examination (e.g. 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. (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 A-scan is useful for the study of the biometric measurements, as well as measurements of intraocular tumour size (e.g. Created for people with ongoing healthcare needs but benefits everyone. 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. Adenomyosis: Inhomogenous myometrial echos on ultrasound can be a sign of adenomyosis, which is a growth of endometrium into the muscle of the uterus (used to be c. 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. This latter method eliminates the risk of indentation of the cornea and underestimation of the anterior chamber depth and axial length. In ultrasonography, pertaining to material that produces echoes of higher amplitude or density than the surrounding medium. 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. The reflected vibration is called an echo. The ultrasound wave is reflected back when it encounters a change in density (or elasticity) of the medium through which it is passing. 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 corner has been mentioned as a wonderful corner for echoes. Greek Mythology A nymph whose unrequited love for Narcissus caused her to pine away until only her voice remained. Eerie echo definition: An echo is a sound which is caused by a noise being reflected off a surface such as a. The silicone probe, which rests on the eye, is separated from the transducer by a water column to segregate the noise from the transducer. echo synonyms, echo pronunciation, echo translation, English dictionary definition of echo. A technique utilizing high frequency ultrasound waves (greater than 18 000 Hz) emitted by a transducer placed near the eye.
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