Clinical Significance of Körner’s Septum in Relation to Occurrence of Squamous Chronic Otitis Media

Abstract

The Körner's septum (KS), persistent petrosquamosal lamina, is a bony lamina (developmental remnant) that extends from the articular fossa to the mastoid apex, above the middle ear, and runs inferiorly and laterally to the facial nerve canal. The petrous and squamous bones meet at this septum. The anatomical structure of KS, which most frequently occurs at the level of the head of the malleus and/or the anterior semicircular canal, is described in depth in this work. The embryological elements of the temporal bone development that result in the formation of KS are taken into consideration. Clinically KS is considered an important anatomical variation, in the development of chronic diseases of the ear like chronic otitis media, especially attic retraction pockets, and cholesteatoma as it can contribute to attic blockage. Also, studies have found a significant association between tympanosclerosis and KS. High-resolution computed tomography (HRCT) and cone-beam computed tomography are the two imaging methods most commonly used to identify KS. It is observed that KS was associated with an increased risk for chronic otitis media, and residual cholesteatoma. The purpose of this review article is to provide a general overview of the KS and its clinical implication, as well as to summarize and discuss the latest clinical data regarding this entity.

Critical Steps and Common Mistakes during Temporal Bone Dissection: A Survey among Residents and a Step-by-Step Guide Analysis

“…According to the participants and their tutors during the dissection courses, it is likely that the inability to correctly identify the lateral semicircular canal was due to the fact that participants often thought they had reached it. Still, it was the Koerner septum, a non-pneumatized structure that contributes to attic blockage and the development of middle ear pathology [21][22][23]. This structure is by definition more superficial than the compact bone of the lateral semicircular canal [21][22][23].…”

“…Still, it was the Koerner septum, a non-pneumatized structure that contributes to attic blockage and the development of middle ear pathology [21][22][23]. This structure is by definition more superficial than the compact bone of the lateral semicircular canal [21][22][23]. Being a non-pneumatized structure, it is easily understandable why this identification is even more difficult in the case of poorly pneumatized mastoids.…”

“…Being a non-pneumatized structure, it is easily understandable why this identification is even more difficult in the case of poorly pneumatized mastoids. [21][22][23]. Therefore, the mastoid antrum should be identified by first locating the Koerner septum, when present, and then perforating it in the anterosuperior quadrant of the dissection.…”

“…To improve the training of young oto-surgeons, all participants agreed on the implementation of a preoperative CT scan of the temporal bone in these dissection courses. This would be very useful and appropriate because it can help young surgeons learn how to interpret radiological findings before an operation and raise awareness on how to identify surgical pitfalls such as high and dehiscent jugular bulb, exposed carotid artery in the tympanic cavity, low middle cranial fossa dura, dehiscences in the tegmen tympani, hypo-pneumatized mastoid, FN course, Koerner septum, and other anomalies [15,[21][22][23][24]28].…”