Circulation · 1974 · 172 citations · 0 references
MedicineBiomedical EngineeringCardiologyDiagnostic ImagingUltrasonographyUltrasoundCardiac ImagingCardiac UltrasonographyCardiac UltrasoundDiagnostic UltrasonographyMedical ImagingUltrasound ImagingCardiac Spatial RelationshipsEchocardiographic Image AcquisitionIntracardiac EchocardiographyPulse-echo ImagingPulse-echo InstrumentationTransducer SensitivityTwo-dimensional Echocardiography
One‑dimensional pulse‑echo ultrasound has been valuable for cardiac diagnosis, but it only visualizes structures along a single line, making spatial relationships difficult to define compared to two‑dimensional systems that display the heart as a plane image composed of many lines. The authors aimed to develop a sector‑scanning system that produces real‑time two‑dimensional echocardiograms using ultrasonic pulse‑echo techniques. The system generates images by rapidly angling a single transducer through a 30‑degree sector from a fixed chest spot, producing 30 complete sectors per second. Using a large‑diameter, highly sensitive transducer, the system yields diagnostic‑quality 2D images of cardiac structures, including the endocardium, in over 100 patients, often in less time than conventional one‑dimensional echocardiography.
During the past several years one-dimensional pulse-echo ultrasound techniques have proven extremely useful in cardiac diagnosis. A one-dimensional system, however, only visualizes structures lying along a single straight line. The spatial relationships of the various cardiac structures are therefore not so easily defined as with two-dimensional systems which display the heart by constructing a plane image composed of many straight lines. We have developed a sector scanning system for obtaining two-dimensional echocardiograms in real time using ultrasonic pulse-echo techniques. Images are produced by angling rapidly a single transducer through a 30-degree sector from a fixed spot (between ribs) on the patient's chest. Thirty complete sectors (or frames) are produced per second. The use of a large diameter transducer ensures that signal strength is good and cardiac structures, including endocardium, can be visualized. Other advantages include high transducer sensitivity, real time imaging and easy visualization of various regions of the heart. Experience with more than 100 patients indicates that diagnostic quality two-dimensional echocardiograms can be readily obtained in essentially the same patients from whom one-dimensional echocardiograms are recorded and can usually be performed in less time.