Ultrasonic Instrumentation for Recording Lateral Pharyngeal Wall Motion

Superior lateral pharyngeal wall movements in speech.

Medial movements of the lateral pharyngeal wall at the level of the velopharyngeal port were examined by using a computerized ultrasound system. Subjects produced CVNVC sequences involving all combinations of the vowels /a/ and /u/ and the nasal consonants /n/ and /m/. The effects of both vowels on the CVN and NVC gestures (opening and closing of the velopharyngeal port, respectively) were asse...

Ultrasonic Instrumentation

Instrumentation Design for Ultrasonic Imaging

The purpose of this chapter is to show how piezoelectric transduction, sound wave propagation, and interaction with scattering targets are taken advantage of in image formation with an ultrasound instrument. These instruments have evolved over the last 40 years from relatively simple handmoved scanners built around an off-the-shelf oscilloscope to rather sophisticated imaging computers. Much te...

Distribution of lateral active earth pressure on a rigid retaining wall under various motion modes

The design of retaining walls depends on the magnitude of active pressure exerted from the backfill. Therefore, estimating the scale of this pressure is a fundamental factor in the design. In this study, to assess the active earth pressure, a rigid retaining wall was built capable of translating and/or rotating with adjustable speed. Further, several physical tests were conducte...

Posterior Pharyngeal Wall Schwannoma

Case report of a posterior pharyngeal wall schwannoma in a 23-year-old female. Hypopharyngeal schwannoma is rare entities and at the time of writing we could find only 10 other cases reported worldwide and this is the eleventh. Complete excision was done intraorally and there is no recurrence after 1 year.