Department of Oto-rhino-laryngology, Head and Neck Surgery, Copenhagen University Hospital Gentofte, Hellerup, Denmark.
Otol Neurotol. 2010 Sep;31(7):1109-14. doi: 10.1097/MAO.0b013e3181e9becb.
A number of middle ear diseases are associated with pathologic bone modeling, either formative or resorptive. As such, the pathogenesis of a sclerotic mastoid has been controversial for decades. Experimental studies on acute middle ear infection have shown progressive osteoneogenesis in the bone structures surrounding the middle ear cavity, and a few studies have reported acute changes of the ossicular chain. However, detailed qualitative and quantitative information on ossicular bone modeling dynamics has not been accounted for and is thus the purpose of this study.
The histopathology of the middle ear bone tissue structures was studied longitudinally in a rat model of acute pneumococcal otitis media, from Days 1 to 28 postinoculation. Resorptive and formative activity was semiquantitated for the ossicles and the bone tissue structures surrounding the middle ear cavity.
Qualitative and semiquantitative histopathology revealed initial osteoresorption, followed by increasing apposition of new bone in the middle ear cavity. Equivalently, the ossicular chain and joints were subject to initial resorption and subsequent new bone formation, but the changes occurred were delayed and to a far lesser extent.
A single incident of acute otitis media changes the osseous structures of the middle ear, which may alter properties of ossicular chain conduction. Modeling of ossicular bone is postponed compared with the bone tissue surrounding the middle ear cavity, and to a much lesser extent. The differentiated modeling pattern suggests that ossicular bone tissue possesses biologic properties resistant to morphologic changes.
一些中耳疾病与病理性骨重塑有关，包括形成性或吸收性。因此，数十年来，硬化性乳突的发病机制一直存在争议。急性中耳感染的实验研究表明，中耳腔周围的骨结构中存在进行性成骨作用，少数研究报告了听小骨链的急性变化。然而，尚未详细说明听小骨骨重塑动力学的定性和定量信息，这就是本研究的目的。
在急性肺炎球菌性中耳炎的大鼠模型中，从接种后第 1 天到第 28 天，对中耳骨组织结构进行了纵向组织病理学研究。对听小骨和中耳腔周围的骨组织结构的吸收和形成活性进行了半定量分析。
定性和半定量组织病理学显示，首先出现骨吸收，随后中耳腔内出现新骨的不断形成。同样，听小骨链和关节首先发生吸收，随后发生新骨形成，但发生的变化延迟且程度较轻。
单次急性中耳炎事件会改变中耳的骨骼结构，这可能会改变听小骨链传导的特性。与中耳腔周围的骨组织相比，听小骨的重塑发生延迟且程度较轻。这种分化的重塑模式表明，听小骨组织具有抵抗形态变化的生物学特性。
