Is aspiration of middle ear effusions prior to ventilation tube insertion really necessary?

A prospective double blind randomized trial of 55 children undergoing myringotomy and insertion of ventilation tubes for bilateral middle ear effusions was undertaken. The aim of the study was to assess the need for clearance of the middle ear by aspiration prior to the insertion of ventilation tubes. The day before surgery the children were assessed by clinical examination, pure tone audiometry and impedance audiometry. At the time of surgery each child underwent bilateral myringotomy, with aspiration of the right or left ear only on a randomly allocated basis. Standard ventilation tubes were then inserted. Postoperative evaluation up to three months following surgery showed no significant differences between the aspirated and the non-aspirated middle ears. We conclude that routine evacuation of the middle ear prior to ventilation tube insertion is not necessary.     

Prospective study of tympanosclerosis developing after grommet insertion

Grommets have been used as a treatment for middle-ear effusions since their introduction by Armstrong in 1954. However, it is now accepted that the presence of a grommet in a tympanic membrane is associated with the development of tympanosclerosis in that membrane. Furthermore, it has been shown that this is a progressive phenomenon and that the incidence increases with time to as much as 65 per cent at 3 to 4 years after grommet insertion (Mawson and Fagan, 1972; Tos and Poulsen, 1976). Initially it was suggested that the development of tympanosclerosis might be due to the middle ear disease rather than to the grommet (McKinnon, 1971). However, most recent studies have found that, in bilateral cases of effusion, tympanosclerosis develops more frequently in ears with a grommet than in those without (Brown, Richards and Ambegaokar, 1978; Lildholt, 1979). This prospective study was designed to show the development of tympanosclerosis in the tympanic membrane of children treated for bilateral middle-ear effusions and to elicit any factors from the clinical history and operative technique which might be associated with the pathogenesis of the complication.     

Tumor necrosis factor in middle ear effusions

The presence of tumor necrosis factor (TNF) was determined in middle ear effusions from 27 ears of children with chronic otitis media with effusion. Cytotoxic activity was assessed by quantitation of target (HeLa) cell death after incubation with the aspirate. Moderate cytotoxic activity was found in 17 of 27 samples (mean cell death of 53% and 32% at 1:2 and 1:4 dilutions, respectively). In ten (37%) of the middle ear effusion aspirates no cytotoxic activity was detected. To confirm that cytotoxicity was due to TNF, 13 of the samples with cytotoxic activity were incubated with a monoclonal anti-TNF antibody and retested. Cytotoxicity was blocked by the anti-TNF antibodies in all cases. Tumor necrosis factor, derived most probably from macrophages or mast cells in the middle ear, may mediate various pathologic processes associated with otitis media, such as generation of mucoid effusion, fibroblast proliferation, and bone resorption.     

鼓膜置管治疗鼻咽癌放疗后分泌性中耳炎疗效观察

目的:探讨鼓膜置管对鼻咽癌(NPC)放疗后的分泌性中耳炎(SOM)的疗效。方法:对32例(51耳) NPC放疗后经鼓膜切开抽液冲洗治疗无效的SOM患者进行鼓膜置管和随访,对治疗耳的咽鼓管功能、听力及其 他症状的改变进行评估。结果:随访6个月～5年,治愈8耳,治愈率为15.7%,有效41耳,总有效率为96.1%。 7耳(13.7%)咽鼓管功能好转,所有重复置管耳的耳功能均得到不同程度的改善。置管后耳漏发生率为25.5%, 鼓膜穿孔发生率为9.8%。结论:鼓膜置管治疗SOM有利于咽鼓管功能的恢复,对于咽鼓管功能已经严重损害 的患耳,重复鼓膜置管是维持耳功能的可靠手段;鼓膜置管的并发症利大于弊。     

Collagenase activity in middle ear effusions

Collagenolytic enzyme activity has been demonstrated in middle ear effusions from patients suffering from otitis media with effusion. Collagenase activity was characterized using different biochemical techniques. Various chemical and physical parameters were titrated for optimal enzyme activity. Bivalent cations activated the enzyme with Ca2+ as the most potent activator. Chelators such as EDTA reduced the enzyme at low concentrations. The enzyme was found to have a higher specific activity in mucoid effusions than in serous and had characteristics similar to granulocyte derived collagenase from human leukocytes. Possible relationships between the presence of collagenase activity and tissue destruction in the middle ear after otitis media with effusion are discussed. The collagenase activity showed wide ranges within different categories of middle ear effusions.     

Prostaglandins in middle ear effusions.

Although otitis media with effusion is usually a self-limiting disease, there are certain cases in which there appears to be chronic progression of the disease with serious sequelae. It has been demonstrated that there are biological mediators of inflammation in the middle ear that are capable of producing mucous membrane pathologic features. Some of these mediators of inflammation may be the prostaglandins. These cyclic fatty acids have been found in ten consecutive middle ear fluids in concentrations that are usually higher than the corresponding serum or plasma. It is suggested that prostaglandins may play an active role in maintaining the inflammatory response in the middle ear in otitis media with effusion.     

Histamine levels in middle ear effusions

The presence of histamine in 131 middle ear effusions was determined by the fluorometric assay technique. This potent mediator of inflammation was found in significant amounts in most of the samples, suggesting that it may play an important role in the pathogenesis of otitis media with effusion. It is postulated that mast cells located in the lamina propria of the tympanic mucoperiosteum are triggered to degranulate and release histamine by anaphylatoxin derived from activation of the complement system.     

Lymphocyte subpopulations in middle ear effusions

The aim of this study was to identify lymphocytes subpopulations in 55 middle ear effusions and peripheral blood samples from 33 children undergoing myringotomy for otitis media with effusion. CD3+, CD4+, CD8+, CD19+ and NK cell populations were investigated using three-colour monoclonal antibody and flow cytometry to quantitative estimation. CD3+ cells were the predominant cell type in effusions (mean 63.3%). Percentage CD4+, CD8+ cells and CD4+/CD8+ ratio was significantly higher in middle ear effusions than in blood. Lymphocyte subset was compared between 22 pairs of effusions from each patient. Percentage of each cells did not differ significantly. The results of this study indicate local regulation of lymphocyte profile in middle ear effusions and the same stadium of immune response in two ears of the same patient.     

白细胞介素6和肿瘤坏死因子-α在分泌性中耳炎渗出液中表达及意义

为探讨细胞因子在分泌性中耳炎发生和转归中的作用，采用酶联免疫吸附试验法，对行鼓膜穿刺术的分泌性中耳炎患者中耳渗出液进行白细胞介素６（ＩＬ－６）和肿瘤坏死因子－α（ＴＮＦ－α）检测。结果示２２份中耳渗出液中ＩＬ－６阳性者为１９份（８６．３６％）；２７份中耳渗出液中ＴＮＦ－α阳性者为１９份（７０．３７％），平均浓度（ｘ±ｓ）分别为５０７．６８±８１３．１１ｎｇ／Ｌ和１８６．８６±１６６．９３ｎｇ／Ｌ。病程短者，ＩＬ－６浓度高（Ｐ＜０．０５）；病程长者，ＴＮＦ－α浓度高（Ｐ＜０．０５），提示ＩＬ－６在疾病早期参与了机体的防御反应；ＴＮＦ－α主要与疾病的持续状态相关，可引起过度炎症反应，导致损害效应。推测在分泌性中耳炎的发病过程中免疫机制可起重要作用。     

Tympanometric diagnosis of middle ear effusions

A review of medical records of unselected children in whom the otoscopic diagnosis of middle ear effusion was uncertain, showed that tympanometry resolved the diagnostic uncertainty with an accuracy of 88 per cent for the prediction of a dry middle ear and an accuracy of 85 per cent for predicting fluid in the middle ear. Tympanometry itself gave inconclusive findings in II per cent of cases. Tympanometry can greatly reduce the need for diagnostic aspiration of the middle ear.     

Quantification of bacteria in middle ear effusions

Quantification of bacteria in various effusion materials (serous, sticky glue, mucopurulent and purulent) collected from 128 middle ears (96 patients) was performed. After sampling, the effusion material was immediately flushed onto a glass slide, stained with acridine orange and examined under a fluorescence microscope. Quantification of bacteria was performed as described. 93% of the serous (n = 28) and 61% of the sticky glue (n = 46) effusion materials contained no bacteria whatsoever. The infectious sticky glue material (n = 18) contained 2.0 x 10(5) (median value), mucopurulent effusion material (n = 24) 2.6 x 10(7) (median value) and purulent effusion (n = 30) 10(9) (median value) bacteria per ml effusion material. Direct microscopic examination of middle ear effusion material, including quantification of the bacteria involved, provides much information about the pathophysiology of the middle ear inflammation.     

Prostaglandin content in human middle ear effusions

Summary The concentrations of prostaglandins (PGs) were measured by a radioimmunoassay in human middle ear effusions (MEEs) obtained from patients with otitis media with effusions. Each sample of MEE was divided into two groups: serous effusions and mucoid ones. The main PG in both the serous and mucoid effusions was TXB₂ (375 and 857pg/ml, respectively), followed by PGE₂ (173 and 459pg/ml, respectively). Smaller quantities of PGD₂ (35 and 64 pg/ml, respectively), PGF_2a (139 and 183 pg/ml, respectively), and 6keto PGF_1a (129 and 201 pg/ml, respectively) were also found in the MEEs. The amounts of each PG in the mucoid effusions were 2 or 3 times higher than those found in the serous effusions, while protein concentrations and the profile of these PGs in the MEEs were almost the same in the mucoid and serous groups. These results suggest that PGs may play an important role as a mediator of the inflammatory responses in the pathogenesis of MEEs.     

Prostaglandin content in human middle ear effusions

The concentrations of prostaglandins (PGs) were measured by a radioimmunoassay in human middle ear effusions (MEEs) obtained from patients with otitis media with effusions. Each sample of MEE was divided into two groups: serous effusions and mucoid ones. The main PG in both the serous and mucoid effusions was TXB2 (375 and 857 pg/ml, respectively), followed by PGE2 (173 and 459 pg/ml, respectively). Smaller quantities of PGD2 (35 and 64 pg/ml, respectively), PGF2 alpha (139 and 183 pg/ml, respectively), and 6ketoPGF1 alpha (129 and 201 pg/ml, respectively) were also found in the MEEs. The amounts of each PG in the mucoid effusions were 2 or 3 times higher than those found in the serous effusions, while protein concentrations and the profile of these PGs in the MEEs were almost the same in the mucoid and serous groups. These results suggest that PGs may play an important role as a mediator of the inflammatory responses in the pathogenesis of MEEs.     

Biochemical evidence of platelet-activating factor (paf) in human middle ear effusions

Platelet-activating factor (PAF) is one of the most potent biological lipid mediators. This is especially true in relation to inflammation. In order to characterize the biochemical features of otitis media with effusion, the authors characterized and determined the concentration of the PAF present in human middle ear effusions obtained from 23 patients with otitis media with effusion. Each sample of middle ear effusion was divided into two groups: serous (n = 12) and mucoid effusions (n = 11). The platelet-activating factor activity was found mainly in mucoid middle ear effusions, and the amounts of PAF were higher in mucoid type (3.55 ± 1.19 ng/g, mean ± standard deviation [SD]) than in the serous type (0.44 ± 0.19 ng/g). Phospholipids obtained from the middle ear effusions contained a large amount of lyso-platelet-activating factor, the biologically inactive precursor or breakdown product of platelet-activating factor. Based on these findings, it is suggested that platelet-activating factor may play an important role as a mediator of the inflammatory responses in the pathogenesis of otitis media with effusion.