I am jibin.i need the a ppt of impedence glottography for presenting the seminar.i have studied at stmarys .and Ipls help me..

Pls send the ppt as soon as possible for the purpose of seminar presentation

A high frequency electrical current of small voltage and amperage (physiologically safe) passes
between two electrodes situated on the surface of the throat at the level of the thyroid cartilage. The basic
configuration of the device is depicted in Fig.1. The electrodes are made of copper, silver or gold. They
have the form of rings or rectangles covering an area ranging from 3 cm
2
to 9 cm
2
. A third electrode is
often used as a reference for impedance measurements. It may be designed as a separate electrode or as a
ring electrode encircling each of the two other electrodes. The electrodes are usually mounted on a
flexible band whose length may be adjusted to hold the electrodes in a steady position and to still allow
the subject to comfortably speak and breathe naturally. Sometimes the electrodes are mounted on a small
holder which is pressed against the throat by hand. A signal generator supplies the electrodes with an AC
sinusoidal current of an alternating frequency usually ranging from 300 kHz to 5 MHz. This frequency is
sufficiently high, so that the current capacitancively bypasses the less conductive skin layer without the
use of additional conductive paste. The generator may produce constant voltage or constitute a constant
current source. The supplied current is different for each particular device, but is not stronger than several
milliamperes. The voltage between the electrodes depends on the tissue impedance but the typical value is
about 0.5 V . In accordance a power dissipation of only several microwatts occurs at the level the
subject's vocal folds