Page 61 - Prosthetic voice rehabilitation-5th edition

61 23456 3. Hilgers FJM, Schouwenburg PF. A new low-resistance, self-retaining prosthesis (Provox) for voice rehabilitation after total laryngectomy. Laryngoscope 1990; 100:1202-1207. 4.2.3 Provox 2 and Provox ActiValve The anterograde replacement of the Provox28 and ActiValve27 voice prostheses is carried out with a disposable insertion tool for insertion of the voice prosthesis directly through the stoma into an established TEP tract. The 'second generation' Provox2 has been adapted for anterograde insertion by having softer flanges (the esophageal flange being the more rigid one), and more curved junctions between the flanges and the shaft. This allows easier insertion in the loading tube and facilitates removal out of the TEP tract with a hemostat. The diameter of the shaft is similar to that of the original Provox prosthesis, but the thickness of the esophageal flange is decreased from 1.6 mm to 1.5 mm, and of the tracheal flange from 1.6 mm to 1.3 mm. The size of the prosthesis (the spacing between the flanges) is marked on the tracheal flange, to facilitate identification of the length of the prosthesis in situ. The available sizes are 4.5, 6, 8, 10, 12.5 and 15 mm. The Provox ActiValve, the special problem solving voice prosthesis, has the same dimensions and sizes, but the valve seat of this prosthesis is slightly longer/bulkier than that of the Provox2. Loading of the Provox2 and ActiValve voice prosthesis into the insertion tool (see also the video at end of this section): the insertion tool consists of a loading tube and an inserter pin. This inserter pin has 2 mark-lines: number 1 is the line indicating the correct position of the prosthesis in the loading tube; number 2 is the line indicating that the esophageal flange is unfolded just outside the tip of the loading tube. The safety string of the voice prosthesis is guided through the center of the opening of the inserter pin, and locked in the top slit of the opening. Thereafter, the prosthesis is placed on top of the inserter (figure below left). Next, the esophageal flange of the voice prosthesis is squeezed between thumb and index finger and hooked into the loading tube ensuring that the esophageal flange is folded forward (figure below middle). The thumb of the other hand should push down and forward