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Biomedical subjects

N L Gregory

Publications and source records attributed to N L Gregory.

11 recordsLinked to original sources

Echocardiographic identification of aorta and main pulmonary artery in complete transposition.

No completely reliable echocardiographic technique has been described for the separate identification of the aorta and main pulmonary artery in complete transposition of the great arteries. A mechanical wide-angle (60 degrees) sector scanner has been applied to this problem in 17 infants and young children, including 8 newborns before angiocardiography. In all patients a longitudinal scan (saggital section) identified the main pulmonary artery by its directly posterior course immediately beyond the pulmonary valve, and the aorta by its retrosternal course upwards before turning posteriorly above the main pulmonary artery. In addition, a high transverse scan showed the precise spatial relation of the great arteries, and, in 11 of the 17, tilting the scanning plane upwards showed branching of the main pulmonary artery. In 8 infants examined with M-mode echocardiography, an upward sweep from the pulmonary valve showed abrupt termination of the echo from the posterior wall coinciding with the posterior arching of the main pulmonary artery.

Aorta, Thoracic

Two-dimensional echocardiography with a wide angle (60 degrees) sector scanner.

A wide angle (60 degrees) sector scanner producing a real-time two-dimensional echocardiogram has been used to examine healthy infants, children, and adults. Its method of use is described and findings from longitudinal and transverse scans are presented. The points of difference between the various types of electronic and mechanical two-dimensional scanning systems are discussed. This equipment minimises problems of chest contact and rib and lung interference and, by providing echocardiograms of high line density from a wide angle, is a suitable real-time two-dimensional scanning system for examining patients of all ages.

Adult

A real time 2-dimensional ultrasonic scanner for clinical use.

The technical details of a real time 2-dimensional ultrasonic scanning system are described, with particular regard to the improved clinical performance over other 2-dimensional scanners. Our instrument is capable of being used with existing ultrasonic equipment extending certain standard ultrasonic machines for use as real time 2-dimensional scanners conveniently and at little cost. Initial results are given and future technical developments are discussed.

Echocardiography

A solid state delayed auditory feedback system for speech therapy.

A delayed auditory feedback system has been constructed using solid state integrated circuit components. The construction of the instrument is described and the advantages of such an electronic device over conventional electro-mechanical systems are discussed.

Analog-Digital Conversion