scholarly journals Variations in Cochlear Size of Cochlear Implant Candidates

2018 ◽  
Vol 23 (02) ◽  
pp. 184-190 ◽  
Author(s):  
Devira Zahara ◽  
Rima Diana Dewi ◽  
Askaroellah Aboet ◽  
Fikri Mirza Putranto ◽  
Netty Delvrita Lubis ◽  
...  

Introduction The cochlear anatomy varies in each individual, and that has an impact on decisions regarding the insertion of electrodes. The measurement of the cochlear size is the routine examination required to choose the proper cochlear implant (CI) electrodes. Objective To acquire normative data on the size of the cochlea (length, width, height, scala timpani [ST] height, cochlear duct length [CDL]) of CI candidates in Medan, Indonesia. Methods This descriptive study was conducted based on high-resolution computed tomography (HRCT) temporal bone data and on HRCT temporal data manipulated to reconstruct three-dimensional (3D) multiplanar images with OsiriX MD DICOM Viewer version 9.5.1 (Pixmeo SARL, Bernex, Geneva, Switzerland) viewer of 18 patients (36 ears) who were CI candidates in Medan, Indonesia, in order to determine cochlear length (A), cochlear width, cochlear height, ST height and CDL, calculated through a simple mathematical function. Results The average cochlear length (A) was 8.75 mm (standard deviation [SD] = 0.31 mm); the average cochlear width was 6.53 mm (SD = 0.35 mm); the average cochlear height was 3.26 mm (SD = 0.24 mm) and the average ST height at the basal cochlea was 1.00 mm (SD = 0.1 mm); and 0.71 mm (SD = 0.1 mm) at the half turn of cochlea. The average total CDL was 32.45 mm (SD = 1.31 mm; range: 30.01–34.83 mm). Conclusion The cochlear size varies in each individual; therefore, the temporal bone measurement of CI candidates using HRCT is essential: for the selection of suitable implant electrodes; to minimize cochlear damages at the insertion of the electrode arrays; and to maximize the hearing improvements.

2021 ◽  
Vol 10 (25) ◽  
pp. 1862-1865
Author(s):  
Sanjana Pradeep ◽  
Swaroop Dev ◽  
Jyothi Swarup Raju ◽  
Shravya Pasunuti

BACKGROUND Chronic otitis media (COM) of squamosal type is associated with cholestatoma with potential complications. Clinical examination and high resolution computed tomography (HRCT) scans are necessary to assess the disease site and extension. The purpose of the study was to compare the preoperative HRCT findings with the intraoperative surgical findings in squamosal type of chronic otitis media as well as various parameters in HRCT temporal bone and intraoperative findings. METHODS A prospective study was conducted on 30 patients aged between 18 and 60 years of both the genders who presented with chronic otitis media squamosal type, for a period of 22 months who attended the outpatient department of ENT. RESULTS HRCT findings and intraoperative findings were compared and results were analysed. Facial canal erosion (P - 0.0031), tegmen plate erosion (P - 0.0001), sigmoid sinus plate erosion (P - 0.002) were found to be statistically significant. Lateral semicircular canal fistula (P - 0.36) and ossicular status malleus (P - 1.000), incus (P - 0.949), stapes suprastructure (P - 0.984), and stapes footplate erosion (P - 0.977) were found to be statistically insignificant. CONCLUSIONS In our study, HRCT imaging for COM squamosal type, accurately depicted the soft tissue mass, erosion of tegmen plate, sigmoid sinus plate, scutum, lateral semicircular canal fistula, incus and suprastructure of stapes erosion and the same were found intraoperatively as well. Our study showed good comparison between the preoperative HRCT scans and the surgical findings in cholesteatoma cases. HRCT is confirmed to be valuable in the diagnosis and in guiding the surgical management of cholesteatoma. KEY WORDS Chronic Otitis Media, Cholesteatoma, HRCT Temporal Bone, Modified Radical Mastoidectomy


2005 ◽  
Vol 119 (9) ◽  
pp. 693-698 ◽  
Author(s):  
Beom-Cho Jun ◽  
Sun-Wha Song ◽  
Ju-Eun Cho ◽  
Chan-Soon Park ◽  
Dong-Hee Lee ◽  
...  

The aim of this study was to investigate the usefulness of a three-dimensional (3D) reconstruction of computed tomography (CT) images in determining the anatomy and topographic relationship between various important structures. Using 40 ears from 20 patients with various otological diseases, a 3D reconstruction based on the image data from spiral high-resolution CT was performed by segmentation, volume-rendering and surface-rendering algorithms on a personal computer. The 3D display of the middle and inner ear structures was demonstrated in detail. Computer-assisted measurements, many of which could not be easily measured in vivo, of the reconstructed structures provided accurate anatomic details that improved the surgeon’s understanding of spatial relationships. A 3D reconstruction of temporal bone CT might be useful for education and increasing understanding of the anatomical structures of the temporal bone. However, it will be necessary to confirm the correlation between the 3D reconstructed images and histological sections through a validation study.


Author(s):  
Akanksha Dhiman ◽  
Ankur Gupta ◽  
Nishi Sharma ◽  
Akhilandeswari Prasad

<p class="abstract"><strong>Background:</strong> Chronic otitis media (COM) affects 0.5-30% of individuals in any community and over 20 million people are estimated to suffer from this condition worldwide. COM often evolves in a continuum. Squamosal disease is more commonly found in poorly pneumatized bones, but whether the sclerosis is relevant to the etiology of the disease or is caused by it, has not been fully resolved. Our study aimed at comparing the mastoid pneumatization patterns obtained using X-ray mastoid and high-resolution computed tomography (HRCT) temporal bone. It was an interventional study.</p><p class="abstract"><strong>Methods:</strong> Sixty patients of unilateral squamosal COM, aged more than 8 years, underwent X-ray mastoid Schuller’s view and HRCT temporal bone, using Philips extended brilliance 48 slice CT.  </p><p class="abstract"><strong>Results:</strong> Upon analysis, in diseased and healthy ears, the coincidence of X-ray and HRCT findings was 63.33% and 80% respectively.</p><p class="abstract"><strong>Conclusions:</strong> HRCT temporal bone should be done in all cases of squamosal COM to know the extent of the disease, pneumatization patterns and the presence of anatomical variations.  </p>


Author(s):  
Vipul V. Chemburkar ◽  
Gagandeep S. Saluja ◽  
Devdas S. Shetty ◽  
Ruchi R. Agrawal

Background: The current study was designed to assess the challenges that arise during cochlear implantation. Hence imaging based grading system, using a structured, 12-point scoring chart was developed with an aim to assess various anatomical factors of temporal bone helpful in contemplating complications involved in surgery and to assess various congenital and acquired abnormalities if detected during scan which can affect cochlear implant surgery.Methods: This was a descriptive study done on 60 patients with sensorineural hearing loss. They were evaluated preoperatively by using HRCT and MRI findings and subsequently underwent cochlear implantation. A 12-point scoring chart was developed based on imaging findings. Surgical times were noted in each case and each imaging point on the scoring chart was correlated with the surgical times.Results: Eleven out of 12 points in the scoring chart proved to be statistically significant in predicting the degree of difficulty of the surgical procedure. One point was not correlating with the surgical timings. Based on the grading system, in the present study, there were 37 patients (61.66%) classified as Grade 1, 16 patients (26.67%) classified as Grade 2 and 7 patients (11.67%) classified as Grade 3.Conclusions: These radiological image findings and its related grading system are relatively easy and quick to assess on readily available pre-operative temporal bone CT scan and MRI. They can form a pre-operative checklist that provides a formalized approach for the surgeons and, in particular surgical trainees, predict and, thus prepare for, potentially challenging cochlear implant cases.


2021 ◽  
Vol 10 (15) ◽  
pp. 3315
Author(s):  
Philippine Toulemonde ◽  
Michaël Risoud ◽  
Pierre Emmanuel Lemesre ◽  
Cyril Beck ◽  
Jean Wattelet ◽  
...  

Cochlear implant is the method of choice for the rehabilitation of severe to profound sensorineural hearing loss. The study of the tissue response to cochlear implantation and the prevention of post-cochlear-implant damages are areas of interest in hearing protection research. The objective was to assess the efficacy of dexamethasone-eluting electrode array on endo canal fibrosis formation by three-dimensional immunofluorescence analysis in implanted Mongolian gerbil cochlea. Two trials were conducted after surgery using Mongolian gerbil implanted with dexamethasone-eluting or non-eluting intracochlear electrode arrays. The animals were then euthanised 10 weeks after implantation. The cochleae were prepared (electrode array in place) according to a 29-day protocol with immunofluorescent labelling and tissue clearing. The acquisition was carried out using light-sheet microscopy. Imaris software was then used for three-dimensional analysis of the cochleae and quantification of the fibrotic volume. The analysis of 12 cochleae showed a significantly different mean volume of fibrosis (2.16 × 108 μm3 ± 0.15 in the dexamethasone eluting group versus 3.17 × 108 μm3 ± 0.54 in the non-eluting group) (p = 0.004). The cochlear implant used as a corticosteroid delivery system appears to be an encouraging device for the protection of the inner ear against fibrosis induced by implantation. Three-dimensional analysis of the cochlea by light-sheet microscopy was suitable for studying post-implantation tissue damage.


2003 ◽  
Vol 117 (8) ◽  
pp. 595-598 ◽  
Author(s):  
Ahmet Koç ◽  
Gazanfer Ekinci ◽  
A. Mert Bilgili ◽  
Ihsan N. Akpinar ◽  
Hamdi Yakut ◽  
...  

The mastoid air cell system is an important contributor to the pathophysiology of middle-ear inflammatory disease. The mastoid cavity is not only an air reservoir, but also an active space for gas exchange. Various methods of temporal bone imaging have been designed to investigate mastoid pneumatization. In this study, we examined 100 normal temporal bones for the evaluation of mastoid pneumatization. Mastoid air cell systems were measured by reconstructed axial and coronal high resolution computed tomography (HRCT) images. The reconstructions were made by a three-dimensional multiplanar volume rendering (3D MPVR) technique. The mean volume of the mastoid air cell pneumatization was 7.9 cm3 (4.0-14.0 cm3, SD = 2.3 cm3). The ears were allocated to the groups with respect to measured mastoid air cell pneumatization. Twenty-eight per cent of the ears have small pneumatization with an aircell system not exceeding 6 cm3. Fifty-two per cent had an air cell system between six and 10 cm3, and 20 per cent had an air cell system exceeding 10 cm3. With its excellent imaging quality and the ability to eliminate bone and soft tissue, HRCT is the best method for evaluating the mastoid air cell system. The 3D MPVR technique must be used tomeasure the temporal bone/mastoid pneumatization for the best results.


Author(s):  
Andrew Tan Kie Kion ◽  
Nik Adilah Nik Othman

Introduction: Acute otitis media (AOM) is an otological disease that is usually self-limit ing. However, certain AOM complicates with abscess development over the deep neck cavity (Bezold's abscess), occiptal abscess (Citelli's) or beneath the temporal muscle (Luc's abscess). Luc's abscess was described as a more benign form of AOM that seldom require extensive surgical drainage.Case report: We report a case of a subperiosteal temporal bone abscess in an immunocompromised patient, which resolved with local drainage of abscess and cultureoriented antimicrobial.Conclusion: Luc's abscess is a rare form of the complication of otitis media, associated with relatively lower morbidity, better prognosis, and requires a limited surgical intervention. High resolution computed tomography (HRCT) temporal bone is highly recommended to evaluate the extent of the disease and to decide for further treatment strategy. The choice of surgery should also be tailored to the patient's premorbid factor.International Journal of Human and Health Sciences Supplementary Issue: 2019 Page: 45


Author(s):  
HIREN DOSHI ◽  
KARNADEV SOLNAKI ◽  
MEETA BATHLA ◽  
ATUL KANSARA ◽  
NAVDEEP CHAVDA ◽  
...  

2019 ◽  
Vol 6 (2) ◽  
pp. 449
Author(s):  
Ponnam Bharath Kumar ◽  
Kiran Mai ◽  
Santosh Karpur

Background: Prior to surgery it is very important that the surgeon is fully aware, and he should have the clear picture as to the extent of the disease and the nature of the disease to give satisfactory surgical outcomes for the patient. HRCT (High resolution computed tomography) is one such guiding tool for the surgeon. The objective was to study usefulness of HRCT scan in attico-antral disease in depicting the status of the middle ear structures.Methods: A total of 30 patients were studied.  HRCT temporal bone was performed by using SIEMENS EMOTION 16 slice CT machine in axial plane and coronal images were reformatted. Findings of HRCT temporal bone were recorded.  Findings of mastoid exploration surgery were recorded. Report of HRCT of temporal bone was correlated with surgical findings and tabulated using percentages.Results: Surgery showed cholesteatoma in 26 (86.6%) patients. Epitympanum was involved in 29 (96.6%) patients in HRCT and 30 (100%) patients at surgery. Extension beyond middle ear cleft was seen in 4 (13.3%) patients in HRCT and 5 (16.6%) patients at surgery. Tympanic segment of facial canal was the most commonly involved, showing erosion in 10 (33.3%) patients in HRCT and 12 (40%) patients at surgery. Lateral SCC was the most commonly involved in bony labyrinth seen in 4 (13.3%) patients in both HRCT and surgery. Erosion of dural plate was seen in 6 (20%) patients in HRCT whereas 9 (30%) patients showed dural plate erosion at surgery.Conclusions: HRCT of temporal bone plays a promising role in pre-operative assessment of cholesteatoma as it depicts the extent of the disease and integrity of most of the middle ear structures.


Sign in / Sign up

Export Citation Format

Share Document