Aerodynamic study of the low-resistance Groningen button in voice prosthesis / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To study the aerodynamic characteristics of low-resistance Groningen voice prosthesis for total laryngectomees and the related clinical significance.</p><p><b>METHODS</b>Three aerodynamic parameters were measured in 24 laryngectomees implanted with low-resistance Groningen voice prosthesis: the sound pressure level (SPL), intratracheal pressure (pressure) and airflow rate (flowrate). Among them, 6 cases were initially implanted with other prosthesis which was replaced by the Groningen buttons later. The parameters were measured for both old and new prosthesis. The relationship between the variables were computed with means of Pearson' s product-moment correlations.</p><p><b>RESULTS</b>The parameters were measured repeatedly among all cases, 180 group data were collected. Screening test showed that the median of sound pressure level, intratracheal pressure and airflow rate are respectively 88.0 dB, 73.6 cm H2O (1 cm H2O = 0.098 kPa) and 123.2 ml/s. Thirty times measurement of patients phonation showed that the correlation between SPL and pressure was not significant (r = -0.058, P > 0.05). The relationship between flow rate and SPL was not significant(r = -0.119, P > 0.05). The correlation between pressure and flow rate was significant(r = 0.699, P < 0.05). CONCLUSIONS When pseudoglottis vibration is produced by sub pseudoglottis air flow, pseudoglottis vibration and voice loudness can not be increased by continuous air flow.</p>

Diagnosis and treatment and prevention of iatrogenic functional aphonia / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To discuss the diagnosis, treatment and prevention of iatrogenic functional aphonia.</p><p><b>METHODS</b>Twenty three patients who either lost their voice or only could whisper after surgery in other hospitals were included in this study as the first group, history was well collected and laryngostroboscopy performed. All cases were confirmed as iatrogenic functional aphonia patients and received phonation therapy. In another group of patients who received vocal cord surgery in our hospital from 2003 to 2005, speaking was restricted while not prohibited after surgery, voice quality was closely observed, and 1028 cases were included.</p><p><b>RESULTS</b>All 23 cases of functional aphonia were cured with phonation therapy. No iatrogenic functional aphonia occurred in the second group of patients.</p><p><b>CONCLUSIONS</b>The iatrogenic functional aphonia can be caused by post operative mistreatment and could be cured with phonation therapy, and it is preventable if speaking is not strictly prohibited after surgery.</p>