Titlebook: real time opthalmic ultrasonography; S. N. Hassani,R. L. Bard Book 1978 Springer-Verlag New York Inc. 1978 Augenheilkunde.Time.Ultraschall

戏法

978-1-4612-6297-8Springer-Verlag New York Inc. 1978

HILAR

fledged

传授知识

Principles of ultrasonography,o propagate. The highest frequency audible to the human ear is 20,000 cycles per second or 20 kilohertz (KHz). Sound waves above this frequency are described as ultrasound. Unlike electromagnetic waves, sound cannot travel across a vacuum.

Lipoma

Ophthalmic anatomy,ease states. Certain structures must be considered in great depth as they are significant in the comprehension of the sonographic anatomy and sonopathology. This chapter will fully outline the anatomic structures and relationships basic to ophthalmological disorders and emphasize areas that are of key importance to the sonographer and eye surgeon.

intercede

Ultrasonic patient history,of information, such as previous surgery, can cause tbe sonographer endless frustration with the confusing scan picture. Symptoms referring to the anterior chamber of the eye will modify the scan with the addition of either a water bath system or a gel stand-off set up to produce better imaging of the anterior structures.

CLEFT

勤劳

Artifacts,nographer or lead to serious misinterpretation of the study. Artifacts must be recognized, their source or sources identified and properly corrected in order to avoid gross errors in the scan interpretation. In this section, we shall only consider the artifacts pertinent to realtime contact B-scanning of the eye which will be discussed below.

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sacrum

Sonography of the lens, may be answered after careful ultrasonography of the vitreoretinal structures. Indeed, a dislocated lens may be discovered floating in the vitreous and cataractous changes in the normally situated lens may be studied.