Ophthalmologic Ultrasound | 合法醫療器材資訊網

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Because the eye is a superficial fluid filled structure, ultrasound is an easy to use modality for visualization of ocular pathology and anatomy [1]. The principles of ocular ultrasound are the same as other applications of this technology. Sound waves are generated at a frequency greater than 20,000 Hz (20 kHz) and reflected back to the transducer by tissue in its path. When the sound wave returns, a piezo-electric crystal in the transducer vibrates, resulting in electrical impulses that are translated into an image or other data [2].

Higher frequency waves penetrate less into tissue but have better resolution. In contrast, lower frequency waves penetrate more deeply but have worse resolution. Ultrasound waves, like other waves, have predictive behaviors based on properties of the medium they travel through. For instance, sound waves have higher velocity when traveling through so...