Influence of Hypercalcemia in the Formation of Tympanosclerosis in Rats

CoCl2 -simulated hypoxia potentiates the osteogenic differentiation of fibroblasts derived from tympanosclerosis by upregulating the expression of BMP-2

Tympanosclerosis (TS) is a result of long-standing middle ear inflammation characterized by fibroblasts ossification. Fibrosis is the last revertible stage in the progress of middle ear inflammation to TS. It was hypothesized that chronic hypoxia could be modulating fibrosis, which in turn additionally further aggravated hypoxia via decreasing oxygen diffusion. However, the effects of hypoxia on osteoinductive activity of fibroblasts have not been explored. Herein, we purposed to explore the role of hypoxia in osteogenic differentiation of fibroblasts derived from TS. The expression of bone morphogenetic protein-2 (BMP-2), hypoxia-inducible factor-1α (HIF-1α), and Vimentin in the human surgical specimens of tympansclerosis was investigated by immunofluorescent staining. Furthermore, cultured fibroblasts were stratified into the following study groups: control, 25, 50, and 100 μM cobaltous chloride (CoCl₂ ) group. BMP-2, as well as HIF-1α levels of expression were detected via western blotting and immunofluorescence analysis. We found that the expression of BMP-2 and HIF-1α was significantly upregulated in TS tissues and these fibroblasts, which was vimentin positive surrounding sclerotic plaques, were also expressing HIF-1α positive. The results also demonstrated that CoCl₂ treatment increased nuclear HIF-1α protein level in the fibroblast. Furthermore, treatment with CoCl₂ significantly increased BMP-2 expression and remarkably elevated alkaline phosphatse activity and the mineralized nodules area. These data illustrate that hypoxia may play an osteogenic role in TS fibroblasts via the elevated expression of a possible osteogenic factor, BMP-2.

Does calcemia influence the onset of myringosclerosis after myringotomy with the insertion of ventilation tubes?

INTRODUCTION

Myringosclerosis is one of the most frequent late complications of the insertion of ventilation tubes, and its aetiopathogenesis remains unknown. The calcification that occurs in the formation of myringosclerosis plaque raises the hypothesis of the presence of a calcium metabolism disorder. The objective is to determine whether calcemia contributes to the development of myringoscelerosis after insertion of ventilation tubes.

MATERIAL AND METHODS

A longitudinal, prospective, analytical cohort study was conducted in patients undergoing myringotomy with the insertion of ventilation tubes due to otitis media with effusion. Calcemia was evaluated pre-operatively and in the follow-up the appearance of myringosclerosis and the percentage of the tympanum involved were evaluated.

RESULTS

The study included 156 patients (297 ears), with calcemia values ranging from 7.6 to 10.2mg/dl. Myringosclerosis was identified in 35.4% of the operated ears. No relationship was found between the appearance of myringosclerosis and calcemia (p=.596). It was found, however, that the greater the percentage of the tympanum affected by myringosclerosis, the lower the calcemia values (p=.014).

CONCLUSION

The population studied had calcemia values within the normal range, which allows us to infer that no changes in calcium metabolism are required for the development of myringosclerosis. Moreover, unlike in previous studies, higher calcium levels are not associated with more myringosclerosis. Calcemia did not influence the appearance of myringosclerosis after myringotomy with the insertion of ventilation tubes.

Predictive factors for the appearance of myringosclerosis after myringotomy with ventilation tube placement: randomized study

Myringotomy with the insertion of ventilation tubes is the most frequent surgical procedure performed in children, and the appearance of myringosclerosis is one of its most frequent long-term complications. The objective of this study is to identify clinical factors and technique variations that may have a relation with the appearance of myringosclerosis, after tube insertion. Patients submitted to myringotomy with transtympanic short-term tube insertion were studied in a longitudinal prospective and analytical cohort study with the prospective randomized open, blinded endpoint (PROBE) methodology, to study the influence of the location of myringotomy (anterior-inferior quadrant or posterior-inferior), directions of the incision (radial or non-radial) and aspiration or not of the middle ear. Our study included 156 patients (297 ears). Myringosclerosis was observed in 35.7 % of the operated ears. It appeared more often in patients with greater number of otitis (p = .001) and with greater number of otorrhea episodes (p = .029) and in patients in whom the tympanogram after the tube extraction was type A (according to Jerger´s classification) (p = 0.016). We identified myringosclerosis in less patients, if the tube was in the tympanic membrane for less than 12 months (p = .009). Myringosclerosis was present more extensively if the tympanic incision was located in the anterior-inferior quadrant, with tympanic involvement superior to 25 % (p = .015). The results observed prove that, underlying the appearance of myringosclerosis, there exists an early inflammatory or infectious process and a final cicatricial process. It was also found that when myringotomy is made in the anterior-inferior quadrant, myringosclerosis appears in a higher percentage of the tympanic membrane; therefore, it is not recommended to do the incision in this quadrant, because it may lead to a reduction of the tympanic membrane vibration.

Manubrio-stapedioplasty: new surgical technique for malleus and incus fixation due to tympanosclerosis

OBJECTIVE

This paper reports the authors' technique of manubrio-stapedioplasty using glass ionomer cement for malleus and incus fixation due to tympanosclerosis.

METHODS

A retrospective case review was conducted of five patients with conductive hearing loss (mean pre-operative air-bone gap of 42.75 dB) treated in a tertiary referral centre. The hearing results of a manubrio-stapedial bone cement ossiculoplasty technique, utilised on the five patients, were analysed. All cases were Wielinga and Kerr tympanosclerosis classification type 2 (attic fixation of the malleus-incus complex with a mobile stapes). The incus and head of the malleus were removed in all patients, and the manubrium was directly connected to the head of the mobile stapes using glass ionomer cement. Patients were evaluated in terms of pre- and post-operative audiometric results; hearing gain and post-operative air-bone gap were the main outcome measures.

RESULTS

Mean post-operative air-bone gap was 5.25 dB. Four patients had an air-bone gap of less than 10 dB; the remaining patient had an air-bone of 12.50 dB.

CONCLUSION

Manubrio-stapedioplasty is an effective method for ossicular reconstruction in cases of malleus and incus fixation due to tympanosclerosis.

[Assessment of Tumor Necrosis Factor alpha gene expression profile in selected structures of middle ear in patients with tympanosclerosis]

AIM OF THE STUDY

Tympanosclerosis is a middle ear disease located in submucous membrane. It leads to the tympanic membrane and ear ossicles fixation which results in severe conductive hearing impairment. The etiology of tympanosclerosis remains unclear. Cytokines play very important role in development of tympanosclerosis. The research aimed to assess gene expression level of pro inflammatory cytokine TNF-α in selected structures of middle ear in patients with chronic otitis media with tympanosclerosis.

METHODOLOGY

The research was performed on middle ear tissues with tympanosclerosis achieved from 30 patients operated on in the Otolaryngology Department of the Medical University of Gdańsk. The control group was formed by tympanic membranes sampled from 17 corpses of patients who died suddenly. Advancement of tympanosclerotic changes were grouped based on Tos classification. The TNF-α gene expression level was measured by real time PCR with specific hydrolysed probes (TaqMan). The gene expression level for TNF-α was correlated with clinical classification of tympanosclerosis.

RESULTS

The level of gene profile expression for TNF-α in selected structures of the middle ear with tympanosclerosis was statistically significant, higher in comparison with the control group. The highest level of expression was observed in group two which is relevant to more advanced tympanosclerosis.

CONCLUSION

Tympanosclerosis is a result of constant inflammatory process and it is modulated by cytokines including TNF-α. The positive correlation between gene expression level of TNF-α and tympanosclerosis could in the future contribute to antiinflammatory, medical treatment of tympanosclerosis.

Could Helicobacter pylori play a role in the aetiopathogenesis of tympanosclerosis?

AIM

The aetiology of tympanosclerosis is not yet clear. This prospective, controlled, clinical study investigated the relationship between Helicobacter pylori and tympanosclerosis aetiology.

MATERIALS AND METHODS

The study included 14 patients with tympanosclerosis and 26 with other forms of chronic otitis media. All patients underwent surgery for chronic otitis media. Mucosal biopsies were taken, and examined for H pylori using the Campylobacter-Like Organism (CLO) test.

RESULTS

Tympanoplasty was performed in 29 patients (72.5 per cent), radical mastoidectomy in eight (20 per cent) and myringoplasty in three (7.5 per cent). The presence of H pylori was tested in all tympanosclerosis biopsies, but in only 26.9 per cent of biopsies from other forms of chronic otitis media. A statistically significant difference in H pylori presence was found (p ≤ 0.01).

CONCLUSION

This study represents a preliminary investigation of the association between H pylori and tympanosclerosis development.