The effect of topical sodium thiosulfate in experimentally induced myringosclerosis

The Effect of Curcumin on the Prevention of Myringosclerosis in Rats

OBJECTIVE

The aim of this study was to investigate the preventative effect of oral curcumin (CMN) on myringosclerosis (MS) in an experimental rat model.

METHODS

The study included 21 female Wistar albino rats randomly separated into three groups. Group 1 was given no treatment (control group). In Group 2 and Group 3, the tympanic membrane (TM) was perforated using a sterile ear pick. The rats in Group 3 were administered oral CMN 200 mg/kg/day. All rats were sacrificed after 16 days. Otomicroscopic and histopathologic examinations were performed on the tympanic membranes.

RESULTS

Histopathologic examinations revealed that there were statistically significant differences between Group 2 and Group 3 in terms of MS degrees (p<0.001) and mean thicknesses of TMs (p<0.001), but there were no differences between Group 1 and Group 3. In respect of MS detected by otomicroscopy, a statistically significant difference was determined between Groups 1 and 2 (p<0.001) and between Groups 2 and 3 (p<0.01), but there was no significant difference between Group 1 and Group 3 (p=0.575).

CONCLUSION

Orally administered CMN can prevent myringosclerosis formation in experimentally induced myringotomies.

Analysis of Risk Factors for Myringosclerosis Formation after Ventilation Tube Insertion

BACKGROUND

This study examined possible risk factors for myringosclerosis formation after ventilation tube insertion (VTI).

METHODS

A retrospective study was performed in a single tertiary referral center. A total of 582 patients who underwent VTI were enrolled in this study. Patients were divided into two groups based on the presence or absence of myringosclerosis: MS+ and MS-. Characteristics of patients were collected through medical chart review; these included age, gender, nature and duration of effusion, type of ventilation tube (VT), duration and frequency of VTI, incidence of post-VTI infection, incidence of intraoperative bleeding, and presence of postoperative perforation. Incidences of risk factors for myringosclerosis and the severity of myringosclerosis in association with possible risk factors were analyzed.

RESULTS

Myringosclerosis developed in 168 of 582 patients (28.9%) after VTI. Patients in the MS+ group had an older mean age than those in the MS- group. The rates of myringosclerosis were higher in patients with older age, serous otitis media, type 2 VT, post-VTI perforation, and frequent VTI. However, there were no differences in occurrence of myringosclerosis based on gender, duration of effusion, duration of VT placement, incidence of post-VTI infection, or incidence of intraoperative bleeding. The severity of myringosclerosis was associated with the duration of effusion and frequency of VTI.

CONCLUSION

Older age, serous effusion, type 2 VT, presence of post-VTI perforation, and frequent VTI may be risk factors for myringosclerosis after VTI; the severity of myringosclerosis may vary based on the duration of effusion and frequency of VTI.

Pharmacokinetics of sodium thiosulfate in Guinea pig perilymph following middle ear application

Hypothesis

To determine the pharmacokinetics of sodium thiosulfate in the inner ear perilymph following middle ear application in Guinea pigs.

Background

Cisplatin chemotherapy is often associated with a dose-dependent high frequency sensorineural hearing loss. Sodium thiosulfate has been shown to reduce cisplatin-induced ototoxicity when given intravenously, but this may limit the tumoricidal effects of the chemotherapy. Recent animal studies looking at middle ear application of sodium thiosulfate have shown prevention of outer hair cell and hearing loss, but the perilymph pharmacokinetics have not yet been established.

Methods

Twenty Guinea pig ears were split into two groups and administered sodium thiosulfate to the middle ear at either a concentration of 250 mg/mL or 50 mg/mL for 30 min. Perilymph samples were then obtained serially through the round window over 6 h. Sodium thiosulfate concentrations were obtained using high-pressure liquid chromatography.

Results

The 250 mg/mL group had a maximum perilymph concentration of 7.27 mg/mL (±0.83) that decreased to 0.94 mg/mL (±0.03) over 6 h. The 50 mg/mL group had an initial concentration of 1.63 mg/mL (±0.17) and was undetectable after 1 h. The half-life of sodium thiosulfate within perilymph was 0.74 h.

Conclusions

and Relevance: The results of this study show that sodium thiosulfate is capable of diffusing through round window and into the inner ear perilymph. Peak levels decline over several hours after exposure. This has a potential application as a localized therapy in the prevention of cisplatin induced ototoxicity.

An Analysis of Surgical Treatment Results of Patients With Tympanosclerosis

OBJECTIVE

The authors aimed to evaluate the intraoperative features and the results of postoperative hearing gain successes of patients with tympanosclerosis who were treated surgically in our clinic.

MATERIAL AND METHODS

A retrospective analysis was conducted on 151 ears with tympanosclerosis of 138 patients who operated because of chronic otitis media or only tympanosclerosis, between January 2007 and June 2014. They were evaluated by appealing complain, complain duration, accompanying systemic disorders, tympanic membrane condition, localization of sclerotic plaque, damage in ossicular chain, existence of cholesteatoma, operation procedure type, hearing reconstruction type, preoperative, and last postoperative audiometric findings in every frequency both bone and air way.

RESULTS

In the group of Wielinga-Kerr Group 3 (isolated stapes fixation), no statistically significant results were found in preoperative and last postoperative audiometric findings in every frequency both bone and air conduction (BC and AC) (P > 0.05). In the Wielinga-Kerr Group some results had significant (P < 0.05) and some results had highly significant (P < 0.001).

CONCLUSIONS

Patients with less impact on ossicular chain and limited localization of sclerotic plaques have better hearing gain. Although surgery is still controversial in tympanosclerosis; it is the most effective treatment till new effective medication is discovered.

Levels of reactive oxygen species in rat tympanic membranes after incisional versus radiofrequency myringotomy

OBJECTIVE

A close relationship between reactive oxygen species (ROS) and myringosclerosis, which is a common complication of myringotomy, was recently reported. The objective of this study was to measure ROS levels directly in rat tympanic membranes using luminol-aided chemiluminescence (CL) in order to compare the levels of ROS after incisional and radiofrequency (RF) myringotomy.

METHODS

Fifteen Sprague-Dawley rats were separated into three groups of five animals each. Bilateral myringotomies were made using an appropriate myringotomy lancet in Group 1 and RF in Group 2. Group 3 served as the control group with no myringotomy. Twenty-four hours after the procedure, all tympanic membranes were inspected with an otomicroscope and then excised for the measurement of ROS using luminol-aided CL.

RESULTS

The mean ROS level in Group 1 was significantly higher than that in Groups 2 and 3 (p<0.05 for both). The difference in mean ROS level between Groups 2 and 3 was not significant (p>0.05). Otomicroscopy revealed increased vascularity and vessel dilation in all tympanic membranes that underwent myringotomy. Vascular dilation was observed in the annular region in the vessels that passed along the long arm of the malleus, in addition to the vessels feeding the anterior and posterior tympanomalleolar folds.

CONCLUSIONS

Although the relationship between ROS and the development of myringosclerosis after myringotomy has been demonstrated, the present study is the first to compare incisional and RF myringotomy based on the measurement of ROS levels. Our results indicate that the increase in ROS due to myringotomy was greater following incisional myringotomy than RF myringotomy.

Panel 8

Background and Objectives

Although serious complications of otitis media (OM) such as brain abscess are rare, sequelae of OM such as tympanic membrane perforation and atelectatic tympanic membrane are quite common. Inner ear sequelae can cause hearing loss and speech and language problems. The objectives of this article are to provide a state-of-the-art review on recent articles on complications and sequelae of OM in different anatomic locations, from the tympanic membrane to intracranial sites, as well as hearing loss and speech and language development.

Data Sources

Primarily PubMed supplemented by Ovid MEDLINE and the Cochrane Database.

Review Methods

All types of articles related to OM complications and sequelae published in English between January 2007 and June 2011 were identified. A total of 127 relevant quality articles are summarized and included in this report.

Results

Key findings are summarized based on the following major anatomic locations and categories: tympanic membrane; cholesteatoma; ossicular problems; mucosal sequelae; inner ear sequelae; speech and language development; extracranial areas, including mastoiditis and facial nerve paralysis; intracranial complications; and future research goals. New information and insights were gained to prevent complications and sequelae.

Conclusion and Implications for Practice

Over the past 4 years, progress has been made in advancing the knowledge on the complications and sequelae of OM, which can be used to prevent and treat them effectively. Areas of potential future research have been identified and outlined.