|
More recently, a second generation Provox voice prosthesis, intended
for anterograde and retrograde use, Provox2, has been developed. This
adapted prosthesis can be inserted during primary puncture at the time
of laryngectomy, or during a secondary procedure at a later date, in the
same manner as the original Provox prosthesis, using the separately available
guide wire. Replacement in the outpatients office, however, can be carried
out now in an anterograde manner directly through the tracheostoma.
For this replacement a simple disposable tool, consisting
of a loading tube and an inserter, is available in the package (figure
right). The Provox2 is available not only in 4.5, 6, 8, and 10 mm shaft
lengths, but also in two additional length, i.e. 12.5 and 15 mm (figure
left). The dimensions of the Provox2 prosthesis are comparable with those
of the original Provox device, but the flanges have been adapted. The
flanges are thinner: the esophageal flange is 1.5 mm instead of 1.6 mm
to enable easier removal from the fistula tract, and the tracheal flange
is 1.3 mm instead of 1.6 mm, to make the resistance towards the esophagus
lower than that towards the trachea, to decrease the possibility of inadvertent
dislodgment into the trachea. Furthermore, the valve construction has
been improved and the tracheal flange contains the size number, allowing
in vivo identification of the length of the prosthesis. |


|