An overview of endoscopic ear surgery in 2018

Abstract

Objective: To provide an overview of Endoscopic Ear Surgery, its development, principles, and penetration in otology practice in 2018.

Data source: PubMed review of literature and cross-sectional email survey of otologists.

Methods: We reviewed all PubMed published articles on use of endoscopy in practice of otology over the last 50 years. Articles were categorized based on date of publication and pattern of utilizing the endoscope. We also conducted two identical email surveys in 2010 and 2018 of otologists on the use of endoscope and tabulated and compared results.

Results: The number of publications on use of endoscope has increased from 6 in 1990 to an accumulated total of 451 in 2018. There has been a clear shift in the area of interest away from diagnostic endoscopy, to endoscope-assisted surgery, and lately, to transcanal endoscopic ear surgery (TEES). Survey results further documented the increased awareness of the value of the endoscope and its increased use in clinical practice.

Conclusion: TEES has gained traction as a subject of research interest and in clinical practice and has lately dominated the discussion on the use of endoscope in otology.

Level of evidence: NA.

Keywords: Endoscopic ear surgery; cholesteatoma; myringoplasty; otoendoscopy; tympanoplasty.

Figure 1

“Survey of endoscopic skills in otology” questionnaire.

Figure 2

Number of publications categorized by the pattern of utilization of the endoscope in ear surgery per the last four decades.

Figure 3

Survey results in 2010 and 2018 of answers to the question “When using the endoscope, which technique do you apply?”

Figure 4

Survey results in 2010 and 2018 of answers to the question “Have you attended any educational program on endoscopic ear surgery?”

Figure 5

Survey results in 2010 and 2018 of answers to the question “Do you believe that there is a role for the endoscope in Cholesteatoma surgery?”

Figure 6

The view from the microscope during transcanal surgery is defined and limited by the narrowest segment of the ear canal. In contrast, the endoscope bypasses this narrow segment and provides a very wide view that allows the surgeon to “look around corners,” even when the zero‐degree scope is used.

Figure 7

The limited view provided by the microscope during transcanal procedures has forced surgeons to perform postauricular mastoidectomy, in which a port parallel to the attic is created after a considerable amount of healthy bone has been removed to enable anterior keyhole access to the attic and access to facial recess and posterior mesotympanum.

Figure 8

Left ear. Endoscopic view through a transcanal endoscopic access after minor removal of bone; the FR is very shallow and more of a flat depression, more or less at the same level as the PE and the vertical segment of FN. FN = facial nerve; FR = facial recess; PE = pyramidal eminence.

Figure 9

A coronal computed tomographic section of the temporal bone, which shows that an axis line drawn through the ear canal ends in the attic rather than the mesotympanum. This almost universal anatomic orientation enables a natural transcanal access to the attic.

Figure 10

Transcanal wide view of the tympanic cavity with the cochleariform process at the center of the visual field.

Figure 11

Multiplanar computerized tomography of a normal tympanic cavity with axial, sagittal, and coronal views demonstrates that the cochleariform process is the anatomic center of the cavity which is aligned with what we see endoscopically in Figure 10.

Figure 12

Three‐dimensional reconstruction of the air spaces within temporal bone, which was derived from a valsalva computerized tomography of a normal temporal bone. Note that microscopic access is misaligned with the most important areas of ventilation, the upstream part of the air cell system.

Figure 13

Left ear: The anterior attic is separated from the supratubal recess and the Eustachian tube by the tensor fold, so there is no direct communication or ventilation anteriorly between the attic and the Eustachian tube.

Figure 14

Left ear: Peaking through the isthmus with a 30° endoscope. CO = the COG; HM = handle of malleus; IS = incudostapedial joint; RE = the recess formed through the insertion of the fold anterior to the COG; TF = tensor fold; TT = tendon of the tensor tympani.

Figure 15

Axial histological section of the temporal bone with the cochlea and malleus simulated for orientation. The blue line is an arbitrary separation between protympanum and “bony Eustachian tube.” ET = Eustachian tube; FP = false passage.