Mahdavi M E, Peyvandi A A,
Volume 65, Issue 3 (2 2007)
Abstract
Background: Cortical Evoked Response Audiometry (CERA) refers to prediction of behavioral pure-tone thresholds (500-4000 Hz) obtained by recording the N1-P2 complex of auditory long latency responses. CERA is the preferred method for frequency–specific estimation of audiogram in conscious adults and older children. CERA has an increased accuracy of determination of the hearing thresholds of alert patients with elevated hearing thresholds with sensory hearing loss however few publications report studies regarding the use of CERA for estimating normal hearing thresholds. The purpose of this research was to further study the accuracy of CERA in predicting hearing thresholds when there is no hearing loss.
Methods: Behavioral hearing thresholds of 40 alert normal hearing young adult male (40 ears) screened at 20 dB HL in 500-8000Hz, predicted by recording N1-P2 complex of auditory evoked long latency responses to 10-30-10 ms tone bursts. After CERA, pure tone audiometry performed by other audiologist. All judgments about presence of responses performed visually. Stimulus rate variation and temporary interruption of stimulus presentation was used for preventing amplitude reduction of the responses. 200-250 responses were averaged near threshold.
Results: In 95% of the hearing threshold predictions, N1-P2 thresholds were within 0-15 dB SL of true hearing thresholds. In the other 5%, the difference between the CERA threshold and true hearing threshold was 20-25 dB. The mean threshold obtained for tone bursts of 0.5, 1, 2 and 4 kHz were 12.6 ± 4.5, 10.9 ± 5.8, 10.8 ± 6.5 and 11.2 ± 4.1 dB, respectively, above the mean behavioral hearing thresholds for air-conducted pure tone stimuli.
Conclusion: On average, CERA has a relatively high accuracy for the prediction of normal hearing sensitivity, comparable to that of previous studies performed on CERA in hearing-impaired populations.
Bazyari Delavar H, Fatahi Bafghi A, Fathol Olomi M R, Peyvandi A A,
Volume 66, Issue 3 (2 2008)
Abstract
Background: Total laryngectomy is the mainstay of treatment for laryngeal cancer. Fistula is one of the most common complications after total laryngectomy. In patients without risk factors such as prior radiotherapy, diabetes mellitus or chronic renal disease, the incidence of pharyngocutaneous fistula is related to wound healing and duration of operation. We have developed a new method that is both simple and without the complication of pharangocutaneous fistula. Herein, we report the efficacy of this innovative method for the closure of total laryngectomy compared to the conventional method for closure.
Methods: In this clinical trial, we included 40 patients with grade T3 or T4 squamous cell carcinoma of the larynx. The total laryngectomy of all patients was performed by the standard method. Twenty patients (case group) were repaired by the new method for closure and 20 patients (control group) were repaired by the standard method. Duration of surgery and hospital stay, bleeding, hematoma, seroma and fistula formation were characterized for every patient and statistically analyzed.
Results: The mean age was 59.8 ±7.8 years for the control group and 61.3 ±6.4 years for the case group. Duration of surgery was 150 ±23.2 minutes and 130 ±18.7 minutes for the control and case groups, respectively (p<0.001). Duration of hospital stay was 10.5 ±1.6 and 3.1 ±0.2 days in the control and case groups, respectively (p<0.002). Bleeding, hematoma or seroma were not seen in either group. Pharyngocutaneous fistula occurred in three patients in control group and was not observed in case group.
Conclusion: This new method for closure shortens the duration of surgery and hospital stay. Furthermore, the patients in the case group avoided the psychological and traumatic side effects of tube feeding associated with fistula. In addition, no other complications were observed with this method. We recommend the use of this simple and efficient method for wound closure after total laryngectomy.