Wael A Alzamil*

Otorhinolaryngology, Hearing and Speech Institute, Cairo, Egypt

*Corresponding Author: Wael A Alzamil, Otorhinolaryngology, Hearing and Speech Institute, Cairo, Egypt.

Received: July 10, 2021; Published: July 22, 2021

Abstract

Background: Congenital aural atresia is common birth defects and is often associated with au­ricular and middle ear deformities. The external auditory canal anomaly varies from slightly narrow to complete atresia. Congenital external auditory canal steno­sis is defined by Jahrsdoerfer., et al. as an EAC with a diameter of less than 4 mm [1]. The surgical management for canal atresia and stenosis is aimed to improve hearing and establish an appropriate auditory canal status for possible application of hearing aids. In clinical practice, we found that patients with canal stenosis and partial atresia have a better postoperative hearing improvement and few­er postoperative complications than those with complete canal atresia [2]. By analyzing the temporal CT images and intraoperative findings in patients with canal atresia and comparing those with images and intraoperative findings from normal canals, we further understand ex­ternal and middle ear development to improve surgical candida­cy selection and avoid unnecessary complications [3]. In addition to the status of the ossicu­lar chain, the degree of development and pneumatization of the tympanic cavity and mastoid, and the course of the facial nerve, the most important information taken from CT and intraoperative findings are the dimensions of the proposed future canal. There are main three dimensions which are the lateral and medial canal diameters and the depth of the canal. Each diameter has two main diagonals, the antero posterior dimension and the supero inferior dimension. This study will focus on the dimensions of the created canal or cavity and whether it is correctable or uncorrectable.

Aim of the Study: To match the C.T. scan and intraoperative findings with the surgical outcome for patients with congenital canal atresia and illustrate the operated uncorrectable dimensions with unfavorable outcome for later proper patient selection and surgical candidacy considerations.

Patients and Methods: A prospective, study conducted from September 2017 to December 2020 on 50 patients suffering congenital canal atresia. Patients have been subjected to preoperative audiological assessment and high resolution C.T. scanning. All patients addressing the study have been scored according to the Jahrsdoerfer Grading Scale selecting patients with scores above 6 (50 patients). All patients have undergone surgical meatocanaloplasty via anterior approach or posterior approach according to the C.T. findings. Intraoperative data collection was done to be matched with preoperative C.T. data and correlated later on with the final outcome. Postoperative regular follow up visits were done obligatory every two to three weeks for at least six months and for regular packing.

Results: Data collection was done involving intraoperative anatomical findings, difficulties or complications, immediate and late postoperative results including the final outcome. Intraoperative measurements have showed marked reduction of the depth of the cavity or the created canal ranging from 1 to 1.5 cm in 47 operated ears having complete atresia and more favorable depth ranging from 1.75 to 2.25 cm in the last three patients with C.T. evidence of partial atresia and less affected tympanic ring. Regarding the antero-posterior distance of the cavity, it was doubled and tripled after radical mastoidectomy in the 47 patients of complete atresia whoever in the three partial atresia patients who have operated via the anterior approach the dimension was equal to the normal auditory canal (0.7 - 1 cm). The supero-inferior dimension was markedly less even after Atticotomy in the 47 patients undergoing radical mastoidectomy with a range of 1 - 1.5 cm. It measured 0.7 - 1 cm in the three patients of partial atresia. No major intraoperative complications were recorded except one 4 years old female who suffered ipsilateral immediate postoperative complete facial paralysis who recovered completely after 4 months. Follow up of all patients recorded progressive circumferential narrowing of their canals and progressive reduction their depth. The final outcome showed shallow canals in 48 patients of depth not more than 1.2 cm and less shallow canals in two patients with their depth 2 cm.

Conclusion: Strict analysis of the C.T. data and intraoperative findings in patients of congenital canal atresia proves their inoperability due to the uncorrectable dimensions even for those patients with the highest Jahrsdoerfer score due to lack of full dimension consideration.

Keywords: Uncorrectable Canal Dimensions; Congenital Canal Atresia

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Citation

Citation: Wael A Alzamil. “Uncorrectable Dimensions in Congenital Canal Atresia Making Us to Revise Operative Candidacy and Patient Selection".Acta Scientific Otolaryngology 3.9 (2021): 104-113.

Copyright

Copyright: © 2021 Wael A Alzamil. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.