Factors influencing the longevity and replacement frequency of Provox voice prostheses

<p><b>INTRODUCTION</b>This study aimed to assess the factors that influence the longevity and replacement frequency of Provox voice prostheses following their placement.</p><p><b>METHODS</b>The medical records of 27 patients who received Provox voice prostheses after total laryngectomy and attended follow-up regularly between 1998 and 2012 were retrospectively reviewed. The success rate of the Provox voice prostheses (i.e. whether speech was achieved), quality of speech achieved, number and type of complications encountered, frequency of prostheses replacement and reasons for prostheses replacements were evaluated.</p><p><b>RESULTS</b>All 27 patients were men and their mean age was 63.0 (range 43-78) years. The mean follow-up period was 60.3 (range 1-168) months. Fluent and understandable speech was achieved in 85.0% of the patients. The mean duration before prosthesis replacement had to be performed was 17.1 (range 1-36) months. The most frequent complication was fluid leakage through the prosthesis. There was a strong positive correlation of 77.1% between the longevity of prostheses and postoperative follow-up duration (r = 0.771; p < 0.01).</p><p><b>CONCLUSION</b>The voice prosthesis is a tool that can be delivered in a practical fashion and replaced easily with no serious complications. It is a means by which speech can be restored, with a high success rate, after total laryngectomy. In the present study, we found that postoperative follow-up duration was the most important factor influencing the longevity of the Provox voice prosthesis.</p>

An Evaluation of the Protective Effects of Thymoquinone on Amikacin-Induced Ototoxicity in Rats

OBJECTIVES: In this study we investigated the probable protective effects of thymoquinone on amikacin-induced ototoxicity in rats. METHODS: Thirty-two healthy rats were divided into four groups (amikacin, amikacin+thymoquinone, thymoquinone, and no treatment). Thymoquinone was fed to the rats via oral gavage in a dose of 40 mg/kg/day throughout the study period of 14 days. Amikacin was given by the intramuscular route in a dose of 600 mg/kg/day. Audiological assessment was conducted by the distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) tests, administered to all rats at the beginning of the study, and also on days 7 and 15. Biochemical parameters were calculated at the termination of the study to evaluate the oxidative status. RESULTS: There were significant decreases in DPOAE values and significant increases in ABR thresholds of the amikacin group on days 7 and 15, as compared to the amikacin+thymoquinone group. While ABR thresholds of the amikacin group increased significantly on days 7 and 15 as compared to their initial values, there were no significant differences between the initial and the 7th and 15th day values of ABR thresholds in the amikacin+thymoquinone group. Total oxidant status and oxidative stress index values of the amikacin+thymoquinone group were significantly lower than those of the amikacin group. Total antioxidant status values of the amikacin+thymoquinone group were significantly higher than those of the amikacin group. CONCLUSION: Our study has demonstrated that the ototoxic effect brought forth by amikacin could be overcome with the concurrent use of thymoquinone.