Osseous External Auditory Canal Research Articles

External ear carcinoma: evaluation of surgical and reconstructive management with postauricular island flap.

Cancers of the auricle and the external auditory canal (EAC) remain a relevant oncological problem. Presentation of the results after resections of conchal bowl and EAC carcinoma (with or without radical mastoid surgery) and after reconstructions (postauricular island flap - PIF). We analysed results of 37 patients with cancers of the auricular conchal bowl and EAC after tumour resection and reconstruction (2000-2017). The cancers were completely excised in all patients, with no recurrences within at least 5 years after surgery. We noted venous congestion in 22 (59.4%) cases, pinning of the operated ear in 18 (48.6%), prominent earlobe in 14 (37.8%), and EAC constriction in 6 (16.2%) cases treated without radical mastoid surgery. Retroauricular approach in cancer of the auricular concha and EAC allowed for accurate evaluation of the tumour extent and proper surgical access, which facilitated complete removal of the tumour. Use of radical mastoid operation with conchal bowl resection and PIF reconstruction in patients with aquamous cell carcinoma or infiltrating basal cell carcinoma of auricular concha and osseous EAC resulted in cancer extirpation and good aesthetic outcomes, despite minor functional consequences. In these cancers mastoidectomy offered a wider access to determine the radicality of oncological resection.

Measurement of the Pediatric and Adult Osseous External Auditory Canal: Implications for Transcanal Endoscopic Ear Surgery.

To develop a method for measuring the diameter of the osseous external auditory canal (OEAC) in pediatric and adult patients. Retrospective analysis of imaging data from patients with a cholesteatoma who underwent transcanal endoscopic ear surgery (TEES) to remove the cholesteatoma by analyzing preoperative sagittal cone beam computed tomography (CBCT) images using ImageJ. Pediatric and adult patients were included who underwent TEES for a cholesteatoma between December 2011 and March 2015 and had available preoperative CBCT scans. Sagittal CT imaging data were analyzed by ImageJ to measure the maximum and minimum Feret diameters along the OEAC. The output data were then analyzed to determine the smallest maximum and smallest minimum Feret diameters for each patient. Fifty-one patients ranging in age from 3 to 83 years old were included in this study. The smallest maximum Feret diameter ranged from 6.5 to 10.1 mm (mean: 8.0 mm) for pediatric patients (<16 years of age) and 6.9 to 15.0 mm (mean: 8.9 mm) for adult patients, while the smallest minimum Feret diameter ranged from 3.6 to 5.9 mm (mean: 5.1 mm) for pediatric patients and 3.4 to 6.4 mm (mean: 5.4 mm) for adult patients. Moreover, the smallest maximum Feret diameters of children were significantly smaller than those of adults. We have developed a novel method for measuring the diameter along the OEAC and determining its narrowest site. This method can be incorporated into the preoperative evaluation of patients who are candidates for TEES.

Morphological Characteristics of Osseous External Auditory Canal and Its Relationship With External Auditory Canal Cholesteatoma in Patients With Congenital Aural Stenosis.

To investigate the characteristics of stenotic external auditory canal (EAC) (e.g., shape, length, orientation, and curvature) and to compare them with those of the cholesteatoma and no cholesteatoma groups, which may help to explain cholesteatoma formation to a certain degree. Computed tomography scans of two groups of patients (with and without EAC cholesteatoma) were analyzed. We determined the degree of microtia, the stenosis of EAC, radius and curvature of osseous EAC bending (abbreviated as OEB-r and OEB-c, respectively), and other anatomic parameters of EAC by using Mimics and Matlab. There was no significant difference in the degree of microtia between the cholesteatoma and no cholesteatoma groups using the Marx grading system. Additionally, no significant difference was found in the stenosis of EAC between the two groups. The OEB-r was smaller in the cholesteatoma group (4.62 ± 0.62 mm) than in the no cholesteatoma group (7.41 ± 0.50 mm), and the OEB-c was found to be larger in the cholesteatoma group (1.55 ± 0.05 × 10 mm) than in the no cholesteatoma group (1.10 ± 0.10 × 10 mm). Moreover, the OEB-c (OR, 8.60; 95% CI, 2.67-27.75) was associated with EAC cholesteatoma formation. The curvature of osseous EAC in the cholesteatoma group was significantly larger than that in the no cholesteatoma group. It is suggested that the curvature of osseous EAC was a risk factor for EAC cholesteatoma formation.

Morphometric Analysis of the External Auditory Canal by Computed Tomography in Indian Population.

Various studies have shown variations in size and shape of different anthropometric measurements of external auditory canal. We conducted an anthropometric study of the three-dimensional anatomy of the osseous external auditory canal (OEAC) using high-resolution computed tomography the temporal bone to identify the variations in subset of Indian population from North India. A retrospective review of high-resolution computed tomography images of the temporal bones of 125 patients (250 external auditory canals) of different ages (mean 28.43years) acquired from September 2014 to February of 2015 was performed. Using a method, as proposed by Mahboubio et al. (Otol Neurotol 33:715-720, 2012), six defined dimensions of the OEAC in the parasagittal planes were recorded at the level of annulus, midcanal and the outermost point of osseous external auditory canal at bony-cartilaginous junction. The length and shape of the OEAC were also studied and the frequency rate of each was recorded. The most prevalent shape of the OEAC was found to be conical (64%) and the mean osseous external auditory canal length was 9.61mm. The length of the OEAC was significantly different between ages above and below 12years while the 6 defined cross sectional dimensions were statistically significant between ages above and below 8years. The history of chronic suppurative otitis media had a significant bearing on the inferior mid-anteroposterior dimension at the level of bony-cartilaginous junction. There was statistically significant difference in supero-inferior diameter in the posterior half at the level of mid-canal and outer bony-cartilaginous junction between males and females. The comprehensive set of standardized measurements collected in this study provides three-dimensional information on osseous external auditory canal geometry. These measurements and the methodology will contribute to the development of element models of the osseous canal for computational modeling purposes and also provide important measurements for design of in-the-canal hearing aids, specialized earplugs and for defining average sizes for canalplasty procedures, in pre- and postoperative surgical planning and assessment of canal atresia and stenosis in Indian population. No such previous study has been done in North Indian population.

Morphological characteristics of external auditory canal in congenital aural stenosis patients

ObjectiveTo investigate characteristics of congenital aural stenosis (CAS) patients' external auditory canal (EAC) (position, length, orientation, etc.) and compare them with normal EAC. MethodsCT images of normal people and CAS patient were utilized. We obtained coordinates of EAC landmarks. Then the Matlab program could calculate some anatomic parameters about EAC, including distances from central point of tympanic annulus (CA), central point of osseous EAC opening (CO), central point of cartilaginous EAC inside opening (CCi), central point of cartilaginous EAC outside opening (CCo) to the Frankfurt horizontal plane (Pfrkt), the median sagittal plane (Psag), the coronal plane (Pcor); orientations of EAC bendings; straight and arc lengths of EAC. ResultsDistances from CA, CO, CCi and CCo to Pfrkt were all shorter in CAS group than control group (p<0.05). The straight and arc lengths of cartilaginous EAC in CAS group were shorter than control group (p<0.05). Straight and arc lengths of EAC in CAS group were shorter than those in control group (p<0.05). The proportion of one bending in cartilaginous EAC in control group was significantly lower than CAS group (p<0.05). Orientations of EAC bendings in CAS group differed from those in control group (p<0.05). ConclusionIn addition to smaller diameters, compared with normal EAC, the position of CAS patients' osseous EAC was higher compared with the normal. The majority of CAS patients have a bending and downward slanting cartilaginous EAC. Orientations of EAC bending in CAS patients were different from normal. Besides, the length of CAS patients' cartilaginous EAC was shorter. However, there were no significant differences between CAS patients and normal people in length of osseous EAC. These differences in anatomic parameters could provide the basis for optimizing the meatoplasty.

The effects of alterations in the osseous external auditory canal on perceived sound quality.

To evaluate the perceptual effect of the altered shape of the osseous external auditory canal (OEAC) on sound quality. Prospective study. Twenty subjects with normal hearing were presented with six simulated sound conditions representing the acoustic properties of six different ear canals (three normal ears and three cavities). The six different real ear unaided responses of these ear canals were used to filter Dutch sentences, resulting in six simulated sound conditions. A seventh unfiltered reference condition was used for comparison. Sound quality was evaluated using paired comparison ratings and a visual analog scale (VAS). Significant differences in sound quality were found between the normal and cavity conditions (all P < .001) using both the seven-point paired comparison rating and the VAS. No significant differences were found between the reference and normal conditions. Sound quality deteriorates when the OEAC is altered into a cavity. This proof of concept study shows that the altered acoustic quality of the OEAC after radical cavity surgery may lead to a clearly perceived deterioration in sound quality. Nevertheless, some questions remain about the extent to which these changes are affected by habituation and by other changes in middle ear anatomy and functionality. 4

Canalplasty in Revision Radical Cavity Surgery Using A Meatal T- Skin Flap Technique

Background: In literature no technique of canalplasty in revision radical cavity surgery has been reported. Yet, inadequate canalplasty is a known contributing factor in troublesome cavities and should be addressed when necessary. Methods: Retrospective cohort analysis of patients undergoing revision radical cavity surgery in which a canalplasty was indicated. All received a canalplasty using a skin flap technique which enables maximal preservation of the delicate epithelial lining of the osseous external auditory canal (OEAC). Results: The described canalplasty technique resulted in quick re-epithelialization (median 8.9 weeks) and dry ears. Only one minor complication was seen. Conclusions: We describe a canalplasty technique that can be used in revision radical cavity surgery and show it is safe and effective. This technique can easily be combined with radical cavity obliteration.

The Shape of the Osseous External Auditory Canal and Its Relationship to Chronic External Otitis

In literature and based on clinical observations, the shape of the osseous external auditory canal (OEAC) has often been suggested to be an etiologic factor in chronic otitis externa (COE). However, to date, no evidence has been presented to confirm this correlation. The aim of this study was to see whether evidence of such a correlation exists, and if so, what shape of the OEAC is related to COE. Using CT scans of 2 groups of patients (with and without COE), a novel and easy to use method was introduced to measure 2 dimensions of the OEAC: the pretympanic recess (the depth (DPTR) and anterior curvature (ACPTR)). In addition, a descriptive classification of the entire OAEC was introduced. The proposed method was demonstrated to be useful as excellent interobserver agreements were found (r = 0.89). No significant differences in the descriptive classifications of the OEAC were observed between COE and the non-COE patients. The DPTR was significantly deeper in COE patients. For the ACPTR, no significant differences were observed. Based on a new method of determining the DPTR, we demonstrate that the DPTR is significantly deeper in COE patients and that the shape of the OEAC is thus of importance in the pathogenesis of COE.

A Novel Method to Determine Standardized Anatomic Dimensions of the Osseous External Auditory Canal

To introduce a novel method for measuring the dimensions of the osseous external auditory canal (OEAC) on computed tomographic images of the temporal bone. Radiology case series. Tertiary care medical center. A retrospective review of high-resolution computed tomographic images of the temporal bones of 69 patients (120 ears) between the ages of 5 and 85 years (mean, 29.1 yr) was performed. Using a novel method to measure dimensions of the OEAC in the parasagittal planes, 6 defined dimensions as well as length and shape of the OEAC were studied at the annulus, midcanal, and the border of the bony cartilaginous junction. There was no statistically significant difference in OEAC dimensions between the male and female subjects or patients with and without a history of chronic otitis media within similar age groups. The length of the OEAC was significantly different between age groups of 5 to 12 and older than 13 years. The 6 defined dimensions were statistically different between the age groups of 5 to 8 years and older. These dimensions were not statistically different between the age groups of 9 to 12, 13 to 18, and older than 18 years. The most prevalent shape of the OEAC was conical (64%). Standardized anatomic dimensions of the OEAC provide important measurements for design of novel in-the-canal hearing aids and specialized earplugs and assist in defining average sizes for canalplasty procedures.

Cavernous hemangioma of the bony external auditory canal

72-year-old female patient was referred to our depart-ment for a left external auditory canal (EAC) tumorincidentally found during her health examination. Otoscopicexamination revealed a reddish mass arising from the roofof the medial end of the osseous EAC (Fig 1), whichmeasured about 5 mm in diameter. There was no history ofotorrhea or pulsatile tinnitus. The tympanic membraneseemed to be uninvolved. She was healthy except for hy-pertension, which was under good medical control. Pure-tone audiometry showed mild-to-moderate sensorineuralhearing loss of both ears, and the tympanograms were bothtype A. A high-resolution CT scan of the temporal boneshowed a small soft-tissue mass occupying the left EACwithout involvement of the epitympanum and adjacent bonywall. Under general anesthesia, this lesion was smoothlyexcised under an otomicroscope via a transcanal approach.The postoperative course was uneventful. The pathologicreport was a cavernous hemangioma (Fig 2). 10 lesions were cavernous hemangiomas, 1 was a capillaryThere was norecurrence 3 months after the operation.

External Auditory Canal Translocation for Cochlear Implantation

The LaryngoscopeVolume 115, Issue 3 p. 555-556 Article External Auditory Canal Translocation for Cochlear Implantation Brian W. Downs MD, Brian W. Downs MD Department of Otolaryngology—Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, U.S.A.Search for more papers by this authorCraig A. Buchman MD, Corresponding Author Craig A. Buchman MD [email protected] Department of Otolaryngology—Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, U.S.A.Craig A. Buchman, MD, G0412 Neurosciences Hospital, CB 7600, Department of Otolaryngology—Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599–7600, U.S.A.Search for more papers by this author Brian W. Downs MD, Brian W. Downs MD Department of Otolaryngology—Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, U.S.A.Search for more papers by this authorCraig A. Buchman MD, Corresponding Author Craig A. Buchman MD [email protected] Department of Otolaryngology—Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, U.S.A.Craig A. Buchman, MD, G0412 Neurosciences Hospital, CB 7600, Department of Otolaryngology—Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599–7600, U.S.A.Search for more papers by this author First published: 03 January 2009 https://doi.org/10.1097/01.mlg.0000157833.31003.b5Citations: 2Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article.Citing Literature Volume115, Issue3March 2005Pages 555-556 RelatedInformation

Modern Perspectives in Otology,

This 252-page volume contains selected papers presented at the Harold F. Schuknecht Society in Boston, June 21-22, 1982, coincident the 200th anniversary of the Harvard Medical School, the 21st anniversary of Dr Schuknecht as LeComte professor of otology and professor of laryngology at the Harvard Medical School, chief of otolaryngology at the Massachusetts Eye and Ear Infirmary, and his retirement from the chairmanship. This volume is dedicated to Dr Schuknecht with affection and admiration by his present and former research fellows. The 24 chapters are written by international authorities in their fields, and include anatomic, physiological, and clinical observations on animals and humans. This material should have a wide appeal to both the clinical and the research scholar. Topics of interest to the chronic ear surgeon include the fate of the osseous external auditory canal and canal skin when detached from its blood supply; the fate of autogenous cancellous

High resolution computed tomography of the osseous external auditory canal: 1. Normal anatomy.

This study of 34 normal ears was conducted in order to define more precisely the normal computed tomographic (CT) anatomy of the osseous external auditory canal. Great variability was found in canal configuration and its relationship to the temporal squama. The understanding of normal CT appearance of the various fissures along the anterior wall of the external canal is important to avoid mistaking fissures for fractures.

Preservation of the posterior canal wall. The wide external auditory canal technique.

The exact line of demarcation between metaplastic and normal tissues in aural cholesteatoma is most difficult to determine even with adequate exposure. Accessibility is a primary factor in removal of cholesteatoma, but there is some doubt that all metaplastic tissues are ever removed completely. By widening osseous external auditory canal as first step in mastoid surgery, middle ear can be examined first, permitting evaluation of disease process and extent of cholesteatoma. If disease is limited to middle ear, adequate access is present for removal of cholesteatoma and subsequent tympanoplastic repair. Through this approach, surgery is extended step-by-step following ramifications of cholesteatoma with least sacrifice of normal tissues. In this technique, the posterior canal wall can be preserved, in most cases, without sacrificing access to any region of middle ear.