Anatomy Of Ear Research Articles

Discovering Middle Ear Anatomy by Transcanal Endoscopic Ear Surgery: A Dissection Manual

The middle ear is located in the center of the temporal bone and bears a highly complex anatomy. The recently introduced exclusively endoscopic transcanal approach to the middle ear is a minimally invasive technique sparing the bone and mucosa of the mastoid bone, since the middle ear is accessed through the external auditory canal. This emerging method has several advantages over the traditional (microscopic) approaches to the middle ear such as the panoramic wide-angle views of the anatomy, the possibility to approach and magnify tiny structures, and the possibility of looking around the corner using angled endoscopes. The cadaveric dissection method presented here consists of an overview on the technical requirements and a precise description of a step-by-step protocol to discover the anatomy of the middle ear. Each step and anatomical structure is carefully described in order to provide a comprehensive guide to endoscopic ear anatomy. In our opinion, this is particularly important to any novice in endoscopic ear surgery as it provides thorough anatomical knowledge and may improve surgical skills.

Educational Benefits for Local Healthcare Providers Participating in a Short-Term International Humanitarian Medical Training Program

Objective: To determine educational benefits for physicians abroad who participated in a United States-based medical mission training program in otologic pathology and surgery. Methods: The sample population included physicians from Peru and Paraguay who participated as trainees in a humanitarian program through the Global ENT Outreach organization. A written survey was distributed to 12 Peruvian participants after a temporal bone course in which surgical anatomy and operative procedures of the ear were taught. The survey was also emailed to 164 physicians who participated in the same temporal bone course in Peru and Paraguay in years past. The Kirkpatrick model for evaluating a training program was used as a guide for survey development. Participants rated their satisfaction with the training as well as knowledge, technical skill, and confidence in performing certain surgical procedures before versus after the training course. Descriptive statistics, the Wilcoxon rank-sum test, and the Wilcoxon- Mann-Whitney test were used for data analysis. Results: Overall, participants were highly satisfied with the quality of the training, with mean satisfaction rating of 4.2 ± 0.77 and would like the organization to return for further training (4.7 ± 0.57). Participants also agreed that they have changed or will change how they perform surgery after taking the course (4.2 ± 0.83). There was a statistically significant increase in self-rated knowledge of mastoid anatomy, middle ear anatomy, chronic otitis media, otosclerosis, and cholesteatoma (p<0.0001). There was also improved selfrated technical skill and confidence in performing tympanoplasty, mastoidectomy, stapedectomy, and ossiculoplasty procedures (p<0.0001). Conclusions: This study highlights positive opinions of communities abroad regarding a visiting humanitarian medical training program, and also suggests achievement of the program’s initial goals of improving knowledge of otologic pathology and increasing technical skill and confidence in performing various surgical procedures

Lend Me Your Ears … for a Review of Anatomy, Development, and Pathology of the External Ear

Lend Me Your Ears … for a Review of Anatomy, Development, and Pathology of the External Ear

Use of narrow band imaging and 4K technology in otology and neuro-otology: preliminary experience and feasibility study.

The advent of the endoscope has facilitated otological surgery in recent years. Advances in optical technology have led to the development of high definition visualisation, such as 4K magnification. Narrow band imaging (NBI) has been shown to improve visualisation of tissue based on varying degrees of vascularity. This is a feasibility study, the first of its kind, aiming to investigate the appearances of middle ear anatomy and pathology (tympanic membrane, tympanosclerosis, cholesteatoma, granulation, endolymphatic sac hydrops, otosclerosis) under the NBI filter, using a high definition 4K endoscope. Qualitative analysis of image detail and operating time in minutes were recorded. The study demonstrates that these two technologies can be implemented with ease into practice, and show a clear differentiation between pathology and normal anatomy. NBI and 4K magnification prove to be useful adjuncts to the surgeon during endoscopic ear surgery.

The Modified Rambo Transcanal Approach for Cochlear Implantation in CHARGE Syndrome.

CHARGE syndrome is associated with a variety of temporal bone anomalies and deafness. The lack of surgical landmarks and facial nerve irregularities make cochlear implantation in this population a challenging endeavor. This study aims to describe a safe and efficacious transcanal approach for cochlear implantation that obviates the need to perform a mastoidectomy and facial recess. Three children with profound hearing loss secondary to CHARGE syndrome. Transcanal cochlear implantation with closure of the ear canal via a modified Rambo meatoplasty. Retrospective chart review of temporal bone anomalies associated with CHARGE syndrome, technical nuances of this transcanal approach, and cochlear implant outcomes. The mean patient age was 2.5 years (range 1.5-3.8 yr). Two were male and two were left ears. All patients had a hypoplastic mastoid, semicircular canal aplasia, and had some degree of cochlear dysplasia. A full cochlear implant insertion was achieved in all cases, even in the presence of grossly abnormal middle ear and facial nerve anatomy. There were no intraoperative or postoperative complications. The mean follow-up was 12.4 months (range, 3.9-25.2 mo). All three patients use their device daily. Their guardians report improved vocalization and environmental awareness. The modified Rambo transcanal approach provides a safe corridor for cochlear implantation in patients with CHARGE syndrome. This approach minimizes the anatomical variations associated with the syndrome and may reduce the risk of electrode extrusion. Implant outcomes in this patient population remain highly variable based on the patient's global cognitive capacity.

Three-dimensional hard and soft tissue imaging of the human cochlea by scanning laser optical tomography (SLOT)

The present study focuses on the application of scanning laser optical tomography (SLOT) for visualization of anatomical structures inside the human cochlea ex vivo. SLOT is a laser-based highly efficient microscopy technique which allows for tomographic imaging of the internal structure of transparent specimens. Thus, in the field of otology this technique is best convenient for an ex vivo study of the inner ear anatomy. For this purpose, the preparation before imaging comprises decalcification, dehydration as well as optical clearing of the cochlea samples in toto. Here, we demonstrate results of SLOT imaging visualizing hard and soft tissue structures with an optical resolution of down to 15 μm using extinction and autofluorescence as contrast mechanisms. Furthermore, the internal structure can be analyzed nondestructively and quantitatively in detail by sectioning of the three-dimensional datasets. The method of X-ray Micro Computed Tomography (μCT) has been previously applied to explanted cochlea and is solely based on absorption contrast. An advantage of SLOT is that it uses visible light for image formation and thus provides a variety of contrast mechanisms known from other light microscopy techniques, such as fluorescence or scattering. We show that SLOT data is consistent with μCT anatomical data and provides additional information by using fluorescence. We demonstrate that SLOT is applicable for cochlea with metallic cochlear implants (CI) that would lead to significant artifacts in μCT imaging. In conclusion, the present study demonstrates the capability of SLOT for resolution visualization of cleared human cochleae ex vivo using multiple contrast mechanisms and lays the foundation for a broad variety of additional studies.

Speculations on Spectacles: Jane Austen’s Eyeglasses, Mrs. Bates’s Spectacles, and John Saunders in Emma

Speculations on Spectacles: Jane Austen’s Eyeglasses, Mrs. Bates’s Spectacles, and John Saunders in <i>Emma</i>

Inner ear malformations: A practical diagnostic approach

Pediatric sensorineural hearing loss is a major cause of disability; although inner ear malformations account for only 20–40% of all cases, recognition and characterization will be vital for the proper management of these patients. In this article relevant anatomy and development of inner ear are surveyed. The role of neuroimaging in pediatric sensorineural hearing loss and cochlear preimplantation study are assessed. The need for a universal system of classification of inner ear malformations with therapeutic and prognostic implications is highlighted. And finally, the radiological findings of each type of malformation are concisely described and depicted. Computed tomography and magnetic resonance imaging play a crucial role in the characterization of inner ear malformations and allow the assessment of the anatomical structures that enable the selection of appropriate treatment and surgical approach.

A comparative study of MED-EL FMT attachment to the long process of the incus in intact middle ears and its attachment to disarticulated stapes head

The Vibrant Soundbridge© (VSB) active middle-ear implant provides an effective treatment for mild-to-severe sensorineural hearing loss in the case of normal middle ear anatomy and mixed hearing loss in middle ear malformation. The VSB floating mass transducer (FMT), with proper couplers, can be installed on various structures of the ossicular chain, e.g., the short and long process of the incus, the stapes head, and the stapes footplate. A long process (LP) coupler is most commonly used for FMT attachment to the long process of the incus with intact ossicular chain, while CliP and Bell couplers are two standardized and reliable methods for FMT attachment to the stapes head with missing incus and malleus. However, the difference and relationship of the vibration properties among these three FMT couplers remain unclear.In the present study, the stapes footplate velocity responses of the LP, CliP, and Bell couplers have been investigated in eight fresh temporal bones (TBs) to evaluate the vibration properties of these three couplers. Normal and reconstructed middle ear transfer functions (METFs) were determined from laser Doppler vibrometer (LDV) measurements. A mastoidectomy and a posterior tympanotomy were performed to expose the ossicular chain. The METFs of the normal middle ear and middle ear with LP-FMT-coupler were compared under acoustic stimulation, thus the mass effect of the FMT with LP coupler was evaluated. Additional comparisons were made between the stapes footplate vibrations of the LP-FMT-coupler (with the intact ossicular chain at the long process of the incus), CliP-FMT-coupler and Bell-FMT-coupler on the stapes head (after incus and malleus removed) under active electromechanical stimulation. After the installation of CliP-FMT-coupler and Bell-FMT-coupler to the middle ear, the average velocity amplitude of the stapes footplate, comparing to the LP-FMT-coupler, was about 15 dB higher between 1 and 6 kHz, and 10 dB lower at about 0.5 kHz. Quantitatively, there was no significant difference between the CliP-FMT-coupler and Bell-FMT-coupler.According to our study, installation of CliP-FMT-coupler or Bell-FMT-coupler on the stapes head provides considerable improvement of the middle ear mechanical and functional responses, comparing with the LP-FMT-coupler in the temporal bone experiments. Moreover, the installation of the Bell-FMT-coupler to the stapes head produces essentially the same footplate velocity responses in comparison to the CliP-FMT-coupler.

Crowd control: Effectively utilizing unscreened crowd workers for biomedical data annotation

Annotating unstructured texts in Electronic Health Records data is usually a necessary step for conducting machine learning research on such datasets. Manual annotation by domain experts provides data of the best quality, but has become increasingly impractical given the rapid increase in the volume of EHR data. In this article, we examine the effectiveness of crowdsourcing with unscreened online workers as an alternative for transforming unstructured texts in EHRs into annotated data that are directly usable in supervised learning models. We find the crowdsourced annotation data to be just as effective as expert data in training a sentence classification model to detect the mentioning of abnormal ear anatomy in radiology reports of audiology. Furthermore, we have discovered that enabling workers to self-report a confidence level associated with each annotation can help researchers pinpoint less-accurate annotations requiring expert scrutiny. Our findings suggest that even crowd workers without specific domain knowledge can contribute effectively to the task of annotating unstructured EHR datasets.

Design and Validation of a Three-Dimensional Printed Flexible Canine Otoscopy Teaching Model.

IntroductionA teaching model was sought to improve canine otoscopy skill and reduce use of teaching dogs.MethodsAn otoscopy teaching model was printed in a flexible medium on a desktop three-dimensional printer from a magnetic resonance image of a canine external ear canal. The model was mounted in a polyvinyl dog mannequin. Validation of the teaching model was sought from student, faculty, and dog perspective. Student perception of prelaboratory training was assessed using a survey regarding their experience. Otoscopy skill was assessed by faculty grading the ear anatomy visualized as well as the time required to prepare for and perform otoscopy and the time to the dog's first sign of aversion. The time data were used to assess whether there was a reduction in use of teaching dogs. Data from students exposed to the otoscopy model as part of their prelaboratory training (n = 20) were compared with those that were not exposed to the model (n = 19).ResultsThe students found prelaboratory training with the model significantly more helpful than prelaboratory training without the model in all aspects of otoscopy (P < 0.05). Use of the model did not alter otoscopy skill (structures seen or time taken) or decrease dog use.ConclusionsThe students found the model helpful, but the best that can be said is the model did not negatively impact their otoscopy skill acquisition. Although the outcome of the study did not indicate a reduction in teaching dog use, the model has replaced live dog otoscopy in the institute's teaching program for initial canine otoscopy exposure.

Merits and demerits of endoscopic tympanoplasty

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;Aim of the study was to evaluate the merits and demerits of endoscopic tympanoplasty compared to conventional microscopic tympanoplasty. &lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;This prospective comparative study was carried out between October 2015 to September 2016 in our otolaryngology department, for a period of 12 months. Total of 40 patients who fit into inclusion criteria, underwent endoscopic tympanoplasty under local anaesthesia with sedation. All laboratory preoperative testing was done; hearing evaluation was done with audiometry. Postoperative follow up was done at 2&lt;sup&gt;nd&lt;/sup&gt; and 3&lt;sup&gt;rd&lt;/sup&gt; month’s period, graft status and hearing evaluation with PTA for all four frequencies 500, 1000, 2000 and 4000 Hz with air conduction and bone conduction thresholds were recorded. &lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;Out of 40 patients, 16 (40%) were males, and 24 (60%) were females, there were 21 (52.5%) cases had moderate perforation, 15 (37.5%) cases had large perforation and 4 (10%) cases had subtotal perforation. Average time taken was of around 1hour and 30minutes, range was (70-140min.). All patients were evaluated for graft status, hearing gain and cosmetic results. Out of 40 patients, 35 (87.5%) patients had successful graft uptake, 2 (5%) patients had graft infection and 3 (7.5%) patients had residual perforation seen postoperatively. &lt;/span&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; &lt;span lang="EN-IN"&gt;Use of endoscope not only serves as a great teaching tool, but also helps to visualize the middle ear anatomy and pathology intraoperatively with minimal soft tissue manipulation better cosmesis and reduced postoperative morbidity. In our study, we found that endoscopic tympanoplasty had better graft uptake rate.&lt;/span&gt;&lt;/p&gt;

Infectious complications of pediatric cochlear implants are highly influenced by otitis media

ObjectiveDetermine the incidence of ear infections in cochlear implant patients, evaluate the contribution of otitis media to complications, describe the bacteriology of otitis media in the cochlear implant population, the treatment provided at our center, and the long term outcome. MethodsData collected included age at implantation, history of otitis media or ear tubes, etiology of hearing loss, inner ear anatomy, postoperative infections, time to infection, route of antibiotic administration, and interventions for infections. Categories of infection were acute otitis media, otitis media with effusion, tube otorrhea, meningitis, scalp cellulitis, and infection at the implant site. ResultsMiddle ear infections were diagnosed in 37% of implanted ears. Extension of middle ear infections into the implant site occurred in 2.8% of all implants (n = 16). Of the 16 infected devices, 10 were successfully treated with antibiotic therapy and did not require explantation. The retained implant group and explanted group both included some middle ear microbes such as Haemophilus influenzae and Streptococcus pneumoniae, as well as skin flora such as Staphylococcus aureus. ConclusionOtitis media in pediatric cochlear implant patients is a common event and usually does not lead to complications of the cochlear implant. However, when the ear infection spreads to the scalp and the implant site, it is still possible to eliminate the infection using antibiotic therapy, particularly when treatment is directed to the specific organism that is recovered from the infected space and the duration and route of antibiotic treatment is carefully considered.

Imaging of the temporal bone in children using low-dose 320-row area detector computed tomography.

The aim of this study was to compare the image quality obtained using low-dose and standard-dose 320-row temporal bone computed tomography (CT) in paediatric patients. Thirteen low-dose CT (120kV/50mAs) and nine standard-dose CT (120kV/100mAs) images from children up to 5years of age were compared for their image quality. The noise and signal-to-noise ratio for bone, fat and air were measured. Two observers assessed the overall image quality and ability to visualize 14 small anatomic structures using a 5-point scale, with a score of 3-5 indicating imaging of diagnostic quality. Noise was significantly higher and the signal-to-noise ratio was significantly lower with low-dose CT. Although the overall image quality and visibility of several structures on low-dose CT were significantly reduced when compared with standard-dose CT, all the image quality scores were 3 or >3. The dose-length products for low-dose CT and standard-dose CT were 59.6mGy·cm and 119.3mGy·cm, respectively. Low-dose CT of the temporal bone using 320-row CT provides images of diagnostic quality for assessment of middle and inner ear anatomy, similar to that provided by the standard-dose protocol, in spite of increased image noise.

Basic principles of endoscopic ear surgery

The wide-angle and high-resolution image afforded by endoscopes allows for improved visualization of ear anatomy compared to the operative microscope. Incorporating the endoscope into otologic practice, however, is challenging. A graduated and stepwise introduction of endoscopic ear surgery (EES) into an established otologic practice is recommended to ensure safe and successful implementation. In this article, we discuss (1) rationale for use of the endoscope in ear surgery, (2) indications, (3) surgical ergonomics, (4) relevant instrumentation for EES, and (5) pearls and pitfalls of transcanal EES approaches.

Transcanal endoscopic tympanotomy

In this article, we describe surgical steps and approaches for transcanal endoscopic tympanotomy. Endoscopic ear surgery can be safely and effectively used for transcanal access to most routine and complex middle ear pathology in children and adults. The superior image detail and wide-angle view of the endoscope greatly enhances its diagnostic and therapeutic value. In the following report, we will review endoscopic middle ear anatomy, basic surgical techniques, and discuss pearls and pitfalls associated with transcanal endoscopic tympanotomy.

Cochlear implantation improves hearing and vertigo in patients after removal of vestibular schwannoma.

With rising quality of speech perception in cochlear implant users, the indication widens. Nowadays, cochlear implantation is reasonable even in vestibular schwannoma patients. Speech perception with a cochlear implant is in these patients as promising as in patients with sensorineural hearing loss. However, the impact of cochlear implantation on vertigo and tinnitus after removal of vestibular schwannoma has not been investigated yet. In a retrospective study, we analysed 12 patients treated with a cochlear implant after removal of vestibular schwannoma. In addition to a promising hearing perception - all patients reported improvement of vertigo. This improvement was also demonstrated by postural analysis. Improvement of tinnitus was achieved in 50% of the patients. Cochlear implantation seems a promising treatment for hearing loss, vertigo and even tinnitus in patients after removal of vestibular schwannoma. However, for successful cochlear implantation with adequate speech perception and improvement of vertigo and tinnitus, functional hearing nerve and intact inner ear anatomy is necessary.

Experimental Visualization of Labyrinthine Structure with Optical Coherence Tomography.

Visualization of inner ear structures is a valuable strategy for researchers and clinicians working on hearing pathologies. Optical coherence tomography (OCT) is a high-resolution imaging technology which may be used for the visualization of tissues. In this experimental study we aimed to evaluate inner ear anatomy in well-prepared human labyrinthine bones. Three fresh human explanted temporal bones were trimmed, chemically decalcified with ethylenediaminetetraacetic acid (EDTA), and mechanically drilled under visual control using OCT in order to reveal the remaining bone shell. After confirming decalcification with a computed tomography (CT) scan, the samples were scanned with OCT in different views. The oval window, round window, and remnant part of internal auditory canal and cochlear turn were investigated. Preparation of the labyrinthine bone and visualization under OCT guidance was successfully performed to a remaining bony layer of 300µm thickness. OCT images of the specimen allowed a detailed view of the intra-cochlear anatomy. OCT is applicable in the well-prepared human inner ear and allows visualization of soft tissue parts.

The endoscopic anatomy of the middle ear (a dissection study)

The objective of the present work was to study the specific endoscopic anatomical features of the middle ear using the dissected temporal bones with the intact tympanic membrane. The 18 cm long endoscopes 4 mm in diameter with a visual angle from 0 to 45 degrees in the combination with some other microinstruments, such as ear pincers, needles, curettes, elevators, and suction tubes, were used during the examination. It was shown that endomeato-transtympanic endosopy provides a panoramic view of almost all structures of the middle ear. After the resection of the posterior bone edge of 'annulus tympanicus', the use of the 45o endoscope ensured the panoramic view not only of certain structures of the middle ear (e.g. the tympanic chord, the stapedius muscle tendon, the entire pyramidal process) but also of the structures of the retrotympanic and anterior epitympanic spaces.

Malformaciones del oído interno: una aproximación diagnóstica práctica

Pediatric sensorineural hearing loss is a major cause of disability; although inner ear malformations account for only 20-40% of all cases, recognition and characterization will be vital for the proper management of these patients. In this article relevant anatomy and development of inner ear are surveyed. The role of neuroimaging in pediatric sensorineural hearing loss and cochlear preimplantation study are assessed. The need for a universal system of classification of inner ear malformations with therapeutic and prognostic implications is highlighted. And finally, the radiological findings of each type of malformation are concisely described and depicted. Computed tomography and magnetic resonance imaging play a crucial role in the characterization of inner ear malformations and allow the assessment of the anatomical structures that enable the selection of appropriate treatment and surgical approach.