Safety and Efficacy of Chitosan-Dextran Hydrogel in the Middle Ear in an Animal Model

2016 ◽  
Vol 21 (4) ◽  
pp. 254-260
Author(s):  
Selin Ünsaler ◽  
Bora Başaran ◽  
Şule Öztürk Sarı ◽  
Eyüp Kara ◽  
Kemal Değer ◽  
...  

Objectives: To investigate the efficacy of chitosan-dextran hydrogel (CDH) in preventing postoperative adhesions between the tympanic membrane (TM) and intratympanic structures, and to evaluate its ototoxicity in an animal study. Methods: In the first step, ototoxicity was evaluated with 7 male albino guinea pigs (GPs) via auditory brainstem responses (ABR) before and 4 weeks after unilateral intratympanic injection of CDH and saline solution contralaterally. In the second step, 12 GPs underwent bilateral ear surgery. The middle ear (ME) mucosa was abraded, and the cavity was filled with CDH on one side and packed with Gelfoam on the contralateral side. A control group of 6 GPs underwent the same procedure except that no material was applied in the ME. The animals were euthanized at the end of the 7th week, and otomicroscopic findings were noted and the temporal bones harvested for the histologic examination. The findings were scored and compared. Results: There was no statistically significant difference between the pre- and postoperative ABR thresholds. In the otomicroscopic findings, the most prominent difference between the two groups was the presence of retraction of the TM in the Gelfoam group. The histopathologic findings revealed a higher degree of inflammation in the Gelfoam group compared with the CDH group. Conclusion: This study demonstrated that CDH has no ototoxic effects in GPs. Its use as an ME packing material revealed significantly less TM retraction and inflammatory reaction compared with Gelfoam.

2019 ◽  
Vol 133 (12) ◽  
pp. 1033-1037 ◽  
Author(s):  
A Das ◽  
S Mitra ◽  
D Ghosh ◽  
S Kumar ◽  
A Sengupta

AbstractObjectiveTo assess the effect of tranexamic acid on intra-operative bleeding and surgical field visualisation.MethodsFifty patients undergoing various endoscopic ear surgical procedures, including endoscopic tympanoplasty, endoscopic atticotomy or mastoidectomy, endoscopic ossiculoplasty, and endoscopic stapedotomy, were randomly assigned to: a study group that received tranexamic acid or a control group which received normal saline. The intra-operative bleeding and operative field visualisation was graded using the Das and Mitra endoscopic ear surgery bleeding and field visibility score, which was separately analysed for the external auditory canal and the middle ear.ResultsThe Das and Mitra score was better (p < 0.05) in the group that received tranexamic acid as a haemostat when working in the external auditory canal; with respect to the middle ear, no statistically significant difference was found between the two agents. Mean values for mean arterial pressure, heart rate and surgical time were comparable in both groups, with no statistically significant differences.ConclusionTranexamic acid appears to be an effective haemostat in endoscopic ear surgery, thus improving surgical field visualisation, especially during manipulation of the external auditory canal soft tissues.


1983 ◽  
Vol 92 (3) ◽  
pp. 249-253 ◽  
Author(s):  
Richard C. Folsom ◽  
Bruce A. Weber ◽  
Gary Thompson

Auditory brainstem responses were recorded from an experimental group of 15 children with early histories of recurrent middle ear disease for the purpose of examining the effects of reduced auditory input on auditory brainstem function. The responses from these children were analyzed in terms of absolute latencies, interwave latencies and latency shifts across sensation level. Comparisons were made to a control group of children with no history of middle ear disease. Results indicated significant differences between the groups. The experimental group demonstrated greater absolute latencies for waves III and V as well as greater interwave latencies. These findings support the interpretation of an association between early recurrent middle ear disease and brainstem function.


2012 ◽  
Vol 127 (2) ◽  
pp. 148-152 ◽  
Author(s):  
E Sozen ◽  
S B Erol ◽  
O Yildirim ◽  
B U Coskun ◽  
T Basak ◽  
...  

AbstractObjective:To evaluate the safety of low-dose transtympanic methotrexate in a rat model.Design:Experimental animal study.Setting:Tertiary training and research hospital.Methods:Twenty-four rats were randomly divided into three study groups. Diluted methotrexate solution was administered transtympanically to fill the middle-ear cavity, twice a week in group one and three times a week in group two. Ringer lactate solution was administered transtympanically three times a week in the control group.Main outcome measures: Local and systemic effects of low-dose transtympanic methotrexate.Results:In the methotrexate groups, middle-ear mucosal oedema was present in all animals. Auditory brainstem response thresholds indicated no inner-ear dysfunction in any group. Liver function and serum haemoglobin levels showed no statistically significant difference in any group. However, liver biopsies from groups one and two showed mild portal hyperaemia.Conclusion:These findings are encouraging, and support further investigation of the topical application of methotrexate in autoimmune hearing diseases, as an alternative or adjunct to transtympanic steroids.


2011 ◽  
Vol 125 (7) ◽  
pp. 668-672 ◽  
Author(s):  
S Singh ◽  
S K Munjal ◽  
N K Panda

AbstractIntroduction:Tinnitus is a disturbing symptom and is often the main reason for otology referral. It is usually associated with hearing loss of varying aetiology, and is thought to begin in the cochlea, with later abnormal central activity. We hypothesise that tinnitus without hearing loss may be caused by central and subcortical abnormalities and altered outer hair cell function.Aim:To compare the auditory brainstem responses, middle latency responses and otoacoustic emissions in normal-hearing individuals with and without tinnitus.Methodology:The audiological test results of 25 normal hearing subjects with tinnitus (age 18–45 years) were determined, and compared with those of a control group.Results:A statistically significant difference was found between study group tinnitus ears vs control group ears, as regards wave I latency prolongation, shortening of wave V and absolute I–III and I–V interpeak latency, enlargement of wave Na and Pa amplitude, and distortion product and transient evoked otoacoustic emission signal-to-noise ratios. There was no statistically significant difference between unilateral vs bilateral tinnitus ears.Conclusion:The pathogenesis and optimum management of tinnitus are still unclear. It often occurs with primary ear disease, usually associated with hearing loss, but may occur in patients with normal hearing. Observed changes in auditory brainstem and middle latency responses indicate central auditory alterations. Tinnitus involves both peripheral and central activity, and complete audiological and neurophysiological investigation is required. Management should be based on both audiological and neurophysiological findings.


1997 ◽  
Vol 111 (3) ◽  
pp. 218-222 ◽  
Author(s):  
William W. Qiu ◽  
Shengguang S. Yin ◽  
Fred J. Stucker ◽  
Mardjohan Hardjasudarma

AbstractGlomus tumours involving the middle ear and the cerebellopontine angle are reported with emphasis on audiological findings. Magnetic resonance imaging (MRI), angiographic and pathological results are presented. Audiological tests, including impedance audiometry, evoked otoacoustic emissions and auditory brainstem responses, are valuable in evaluation of the effect of glomus tumours on the auditory system as well as their pathological extent.


2018 ◽  
Vol 41 (4) ◽  
pp. 390-396 ◽  
Author(s):  
Paweł Plakwicz ◽  
Joanna Abramczyk ◽  
Julita Wojtaszek-Lis ◽  
Jolanta Sajkowska ◽  
Barbara Warych ◽  
...  

Summary Objectives The aim of this study was to evaluate characteristics of patients with unilateral transmigration of a mandibular canine in the largest study group presented until now. Materials and methods The study group consisted of 93 patients with unilateral transmigration of mandibular canine; the control group included 85 non-affected patients. Type of transmigration, status of deciduous and permanent canines, prevalence of missing teeth, class of occlusion, and space conditions were assessed to draw comparisons between groups. Results In this study, 64.5 per cent patients presented type 1 of transmigration; types 2, 3, 4, and 5 were present in, respectively, 23.7, 5.4, 4.3, and 2.1 per cent patients. There was a clear, statistically significant difference (P < 0.0001) between the mean crown and apex migration and angulation for the three groups of canines (transmigrated, contralateral, and control), whereas no differences were observed for the total number of permanent teeth present. In the study group, 73.1 per cent patients retained their primary canine on the affected side and 18.3 per cent on the contralateral side; in the control group, 22.3 per cent subjects had at least one primary canine. There was a statistically significant difference in the distribution of types of malocclusion between the study and the control groups. Conclusions Transmigration of mandibular canine was associated with the presence of retained primary canine on the affected side, higher mesial tilting of contralateral mandibular canine when compared to the canines in the control group. Additionally, higher prevalence of Angle’s Class I occlusion in patients with canine transmigration was recorded.


PEDIATRICS ◽  
1994 ◽  
Vol 93 (1) ◽  
pp. 50-53 ◽  
Author(s):  
Masahisa Funato ◽  
Hiroshi Tamai ◽  
Seiichi Shimada ◽  
Hajime Nakamura

Objective. The management of nonhemolytic hyperbilirubinemia in term newborns is controversial. To evaluate the usefulness of serum unbound bilirubin concentrations (UBCs) in the management of hyperbilirubinemia, we compared the concentrations with abnormal auditory brainstem responses (ABRs). Methods. ABRs and serum UBCs in 37 hyperbilirubinemic term newborns (total bilirubin concentrations [TBCs] ≥20 mg/dL and direct bilirubin concentrations &lt;2 mg/dL) were measured before treatment with either phototherapy or exchange transfusions. Eight of these newborns had blood incompatibilities. These hyperbilirubinemic newborns were divided into three groups according to the findings of ABR: group A, normal ABR (n = 18); group B, prolonged latency of wave I only (n = 8); and group C, prolonged interpeak latency of wave I-III/I-V and/or poor amplitude (n = 11). Results. The peak TBC was significantly different between groups A and C (22.8 ± 2.2 mg/dL and 25.4 ± 2.5 mg/dL, respectively; P &lt; .05), though there were no differences between groups A and B and between groups B and C. The peak UBCs in groups B (1.27 ± 0.7 µg/dL) and C (1.34 ± 0.37 µg/dL) were significantly higher than in group A (0.78 ± 0.26 µg/dL) (P &lt; .05 and P &lt; .01, respectively), though there was no significant difference in the peak UBC between groups B and C. Abnormal ABR findings were more clearly associated with the level of UBC at 1.0 µg/dL than that of TBC at 23 mg/dL by multiple logistic regression analysis (odds ratio 16.6, P = .0026, vs 4.2, P = .1272). Conclusions. These results suggest that measuring UBC may help in evaluating the possible risk of bilirubin encephalopathy in full-term newborns when there is vigintiphobia (fear of 20).


2019 ◽  
pp. 014556131987431
Author(s):  
Burak Mustafa Taş ◽  
Gökçe Şimşek ◽  
Musa Azman ◽  
Rahmi Kılıç

Ototoxicity is the general name of cochlear and vestibular organ injury resulting from encountering various therapeutic agents and chemical substances. Cisplatin is commonly used in the treatment of many cancers. In this study, the efficacy of intratympanic steroids was compared for preventing cisplatin ototoxicity. In this study, 32 (64 ears) rats were used by separating into 4 groups. Cisplatin was administered intraperitoneally to the first group (n = 8). Methylprednisolone and then cisplatin were administered intratympanically to the second group (n = 8). On the third group (n = 8), dexamethasone and then cisplatin were administered intratympanically. To the fourth group (n = 8), 0.9% NaCl and then cisplatin were given intratympanically. Otoacoustic emission (OAE) measurements and auditory brainstem responses (ABRs) tests were performed on all groups before and 72 hours after the procedure. Pretreatment of ABR-IV values were 4.29 ± 0.19 milliseconds in group 2 and 4.27 ± 0.16 milliseconds in group 3, whereas posttreatment ABR-IV values were 4.95 ± 0.35 milliseconds in group 2 and 4.65 ± 0.26 milliseconds in group 3. The ABR-IV values were measured significantly shorter in the rats given dexamethasone and methylprednisolone, according to control and cisplatin groups ( P < .001). Pretreatment of ABR I-IV interval values were 2.98 ± 0.34 milliseconds and 3.03 ± 0.42 milliseconds in group 1 and group 4, respectively, and ABR I-IV interval values in group 1 and group 4 posttreatment were 3.49 ± 0.39 milliseconds and 3.5 ± 0.39 milliseconds in group 1 and group 4, respectively. Auditory brainstem responses I-IV interval was significantly longer in the cisplatin and control group than in the rats given dexamethasone and methylprednisolone ( P < .001). After cisplatin treatment, OAE amplitudes decreased significantly in group 1 and group 4 for all frequencies, while OAE values were protected in methylprednisolone and dexamethasone group ( P < .001). In conclusion, it has been shown that both agents have protective effects on cisplatin ototoxicity, with dexamethasone slightly more than methylprednisolone.


2009 ◽  
Vol 123 (6) ◽  
pp. 603-608 ◽  
Author(s):  
T Just ◽  
E Lankenau ◽  
G Hüttmann ◽  
H W Pau

AbstractObjective:Optical coherence tomography was used to study the stapes footplate, both in cadaveric temporal bones and during middle-ear surgery.Materials and methods:Optical coherence tomography was conducted on five temporal bone preparations (from two children and three adults) and in eight patients during middle-ear surgery. A specially equipped operating microscope with integrated spectral domain optical coherence tomography apparatus was used for standard middle-ear surgical procedures.Results:This optical coherence tomography investigation enabled in vivo visualisation and documentation of the annular ligament, the different layers of the footplate and the inner-ear structures, both in non-fixed and fixed stapes footplates. In cases of otosclerosis and tympanosclerosis, an inhomogeneous and irregularly thickened footplate was found, in contrast to the appearance of non-fixed footplates. In both fixed and non-fixed footplates, there was a lack of visualisation of the border between the footplate and the otic capsule.Conclusions:Investigation of the relatively new technology of optical coherence tomography indicated that this imaging modality may assist the ear surgeon to assess the oval window niche intra-operatively.


2020 ◽  
Vol 10 (8) ◽  
pp. 559 ◽  
Author(s):  
Verena Scheper ◽  
Ira Seidel-Effenberg ◽  
Thomas Lenarz ◽  
Timo Stöver ◽  
Gerrit Paasche

Degeneration of neurons, such as the inner ear spiral ganglion neurons (SGN), may be decelerated or even stopped by neurotrophic factor treatment, such as brain-derived neurotrophic factor (BDNF), as well as electrical stimulation (ES). In a clinical setting, drug treatment of the SGN could start directly during implantation of a cochlear implant, whereas electrical stimulation begins days to weeks later. The present study was conducted to determine the effects of consecutive BDNF and ES treatments on SGN density and electrical responsiveness. An electrode drug delivery device was implanted in guinea pigs 3 weeks after deafening and five experimental groups were established: two groups received intracochlear infusion of artificial perilymph (AP) or BDNF; two groups were treated with AP respectively BDNF in addition to ES (AP + ES, BDNF + ES); and one group received BDNF from the day of implantation until day 34 followed by ES (BDNF ⇨ ES). Electrically evoked auditory brainstem responses were recorded. After one month of treatment, the tissue was harvested and the SGN density was assessed. The results show that consecutive treatment with BDNF and ES was as successful as the simultaneous combined treatment in terms of enhanced SGN density compared to the untreated contralateral side but not in regard to the numbers of protected cells.


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