Showing 4 results for Peyvandi
Peyvandi H, Talebpoor M, Begam Orang Z, Ahmadi Amoli H, Motalebi N, Hallaj Mofrad H.r, Molavi B, Asheri H,
Volume 64, Issue 9 (1 2006)
Abstract
Background: Performing traditional autopsy mostly seems to be unpleasant in dead persons' relatives' opinion. This study aimed to determine the accuracy of laparoscopic examination of intra abdominal organs in comparison to the traditional autopsy in trauma victims.
Methods: From December 2004 to September 2005, 50 fresh cadavers of blunt trauma victims were studied in less than 24 hours from death time. Intraperitoneal and retroperitoneal organs were first evaluated by laparoscope and then the traditional autopsy was performed as gold standard. The organs were assessed regarding impairment and its grade in both ways. Diagnostic accuracy of laparoscope was determined for each case with 95% confidence interval using Fisher's exact test.
Results: The values of overall and distinct accuracy of laparoscopic examination for intraperitoneal and retroperitoneal organs were significantly comparable with traditional autopsy. The accuracy of laparoscopic evaluation of intraperitoneal and retroperitoneal organs were 90% (95% CI of 81.7% to 94.8%) and 92% (95% CI of 84.7% to 96%) respectively in comparison to open autopsy. The overall accuracy of laparoscopic examination was 84% (95% CI of 74.3% to 90.5%).
Conclusion: The sensitivity and specificity of laparoscopic examination for intraperitoneal but not retroperitoneal organs were acceptable in comparison to open autopsy. Laparoscopic examination seems to be an eligible substitute for the traditional autopsy in assessment of intraperitonel organs.
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.
Somayeh Niknazar , Leila Simani , Hassan Peyvandi , Ali Asghar Peyvandi ,
Volume 77, Issue 8 (November 2019)
Abstract
The mammalian cochlea is a highly complex structure which contains several cells, including sensory receptor or hair cells. The main function of the cochlear hair cells is to convert the mechanical vibrations of the sound into electrical signals, then these signals travel to the brain along the auditory nerve. Auditory hair cells in some amphibians, reptiles, fish, and birds can regenerate or replace by new cells, but irreversible damage to the mammalian hair cells are not being replaced through differentiation of the internal epithelial cells in the inner ear. Indeed, mammalian auditory hair cells do not spontaneously repair or regenerate after development. Sometimes, functions of damaged hair cells may be restored, but in most cases, there is no such possibility and permanent hearing loss occurs. Several factors such as chronic ear infections, genetic disorders, drug abuse, acoustic trauma and aging can damage the cochlea, resulting in permanent hearing loss. More than 250 million people in the world have disabling hearing impairment. Deafness is caused by damage to sensory hair cells or spiral ganglion neurons. Although hearing aids and cochlear implants were used for improvement of hearing loss, but they do not restore normal hearing. In addition, application of new biological approaches to induce auditory hair cell regeneration provides more comprehensive treatment for hearing loss. Cell therapy is considered a promising way in the treatment of several diseases such as Parkinson, diabetes and cardiac diseases. According to recent research, cell therapy can be useful in hair cell regeneration. Cell therapy is effective in hearing loss when stem cell differentiates into hair cells with appropriate morphology, electrical activity and capacity for suitable innervations with inner ear tissues. In fact, stem cell-derived neurons need to project neural processes toward the sensory hair cells and the cochlear nucleus neurons. In this regard, studies focus on methods in which hair cells can be provided from exogenous and endogenous stem cells. Here, we review cell therapy approaches in repair damaged cochlear hair cells, as well as imitations and problems of its clinical application.