Navigation-Guided Transmodiolar Approach for Auditory Nerve Implantation via the Middle Ear in Humans

2015 ◽  
Vol 20 (2) ◽  
pp. 128-135 ◽  
Author(s):  
Walid Farouk Sobhy Afifi ◽  
Caroline Guigou ◽  
Stéphane Mazalaigue ◽  
Jean-Paul Camuset ◽  
Frédéric Ricolfi ◽  
...  
Keyword(s):  
Middle Ear ◽  
Auditory Nerve ◽  
Interindividual Variation ◽  
Ct Scans ◽  
Anatomical Landmarks ◽  
Target Registration Error ◽  
Temporal Bone Ct ◽  
Temporal Bones ◽  
Anatomical Parameters ◽  
Nerve Implantation

The aim of this study was to assess the surgical feasibility of a transmodiolar approach via the middle ear cavity for an auditory nerve implantation in humans. In the first part of the study, 6 adult human temporal bones underwent a navigator-guided transmodiolar implantation via the middle ear space after a radical mastoidectomy. In the second part, 122 temporal bone CT scans were analyzed for anatomical parameters relevant to this approach. The nerve implantation was feasible in all temporal bones in laboratory conditions, with a mean target registration error of 0.065 ± 0.0583 mm (n = 6). Evaluation of anatomical parameters on CT scans also supported the feasibility. There was a significant interindividual variation of the modiolar axis and the entry point in relation to visible anatomical landmarks, highlighting the necessity for surgical preplanning.

The influence of race on the position of the jugular bulb

1995 ◽  
Vol 109 (7) ◽  
pp. 610-613 ◽  
Author(s):  
W. K. Low ◽  
J. E. Fenton ◽  
P. A. Fagan ◽  
W. P. R. Gibson
Keyword(s):  
Racial Differences ◽  
Clinical Significance ◽  
Middle Ear ◽  
Sagittal Plane ◽  
Jugular Bulb ◽  
Ct Scans ◽  
High Jugular Bulb ◽  
Chi Squared ◽  
Temporal Bones ◽  
Inferior Limit

AbstractThe position of the jugular bulb (JB) is of great clinical significance to the otologist. A high and laterally situated jugular bulb may pose difficulties when dealing with the middle ear while a high and medially sited jugular bulb can create problems in neuro-otological surgery. This paper aims to study possible racial differences in the position of the jugular bulb.Fine-cut computed tomogram (CT) scans of temporal bones (in the axial plane) of 34 Caucasians and 34 Chinese were studied. The position of the jugular bulb was determined with reference to the midpoint of the lumen at the inferior limit of the cochlea (mpC).Of the 60 Caucasian and 58 Chinese temporal bones with identifiable jugular bulbs, 33 jugular bulbs of the Caucasian (55 percent) and 34 jugular bulbs of the Chinese (58.6 percent) were at the same height or higher than the mpC (p = 0.2; chi-squared test). The midpoint of the jugular bulb was 8.67 ± 1.73 and 8.61 ± 2.49 mm posterior to the mpC for the Caucasian and Chinese respectively (p = 0.2; t-test). However, the midpoint of the jugular bulb of eight Caucasian (24.2 percent) and 22 Chinese (64.7 percent) were medial to the mpC (p<0.001; chi-squared test).Race does not influence the height of the jugular bulb nor its position in the sagittal plane but can influence whether a high jugular bulb is medially or laterally situated.

scholarly journals Laparoscopic augmented reality registration for oncological resection site repair

2021 ◽  
Author(s):  
Fabian Joeres ◽  
Tonia Mielke ◽  
Christian Hansen
Keyword(s):  
Augmented Reality ◽  
Time Pressure ◽  
Tumour Resection ◽  
Anatomical Landmarks ◽  
Proof Of Concept ◽  
Registration Accuracy ◽  
Target Registration Error ◽  
Concept Evaluation ◽  
Navigation Support ◽  
Challenges And Opportunities

Abstract Purpose Resection site repair during laparoscopic oncological surgery (e.g. laparoscopic partial nephrectomy) poses some unique challenges and opportunities for augmented reality (AR) navigation support. This work introduces an AR registration workflow that addresses the time pressure that is present during resection site repair. Methods We propose a two-step registration process: the AR content is registered as accurately as possible prior to the tumour resection (the primary registration). This accurate registration is used to apply artificial fiducials to the physical organ and the virtual model. After the resection, these fiducials can be used for rapid re-registration (the secondary registration). We tested this pipeline in a simulated-use study with $$N=18$$ N = 18 participants. We compared the registration accuracy and speed for our method and for landmark-based registration as a reference. Results Acquisition of and, thereby, registration with the artificial fiducials were significantly faster than the initial use of anatomical landmarks. Our method also had a trend to be more accurate in cases in which the primary registration was successful. The accuracy loss between the elaborate primary registration and the rapid secondary registration could be quantified with a mean target registration error increase of 2.35 mm. Conclusion This work introduces a registration pipeline for AR navigation support during laparoscopic resection site repair and provides a successful proof-of-concept evaluation thereof. Our results indicate that the concept is better suited than landmark-based registration during this phase, but further work is required to demonstrate clinical suitability and applicability.

Otopathologic Abnormalities in CHARGE Syndrome

2021 ◽  
pp. 019459982110089
Author(s):  
Rafael da Costa Monsanto ◽  
Renata Malimpensa Knoll ◽  
Norma de Oliveira Penido ◽  
Grace Song ◽  
Felipe Santos ◽  
...  
Keyword(s):  
Facial Nerve ◽  
Middle Ear ◽  
Spiral Ganglion ◽  
Internal Auditory Canal ◽  
Semicircular Canals ◽  
Charge Syndrome ◽  
University Of Minnesota ◽  
Bony Canal ◽  
Ganglion Neurons ◽  
Temporal Bones

Objective To perform an otopathologic analysis of temporal bones (TBs) with CHARGE syndrome. Study Design Otopathologic study of human TB specimens. Setting Otopathology laboratories. Methods From the otopathology laboratories at the University of Minnesota and Massachusetts Eye and Ear Infirmary, we selected TBs from donors with CHARGE syndrome. These TBs were serially sectioned at a thickness of 20 µm, and every 10th section was stained with hematoxylin and eosin. We performed otopathologic analyses of the external ear, middle ear (middle ear cleft, mucosal lining, ossicles, mastoid, and facial nerve), and inner ear (cochlea, vestibule, internal auditory canal, and cochlear and vestibular nerves). The gathered data were statistically analyzed. Results Our study included 12 TBs from 6 donors. We found a high prevalence of abnormalities affecting the ears. The most frequent findings were stapes malformation (100%), aberrant course of the facial nerve (100%) with narrow facial recess (50%), sclerotic and hypodeveloped mastoids (50%), cochlear (100%) and vestibular (83.3%) hypoplasia with aplasia of the semicircular canals, hypoplasia and aplasia of the cochlear (66.6%) and vestibular (91.6%) nerves, and narrowing of the bony canal of the cochlear nerve (66.6%). The number of spiral ganglion and Scarpa’s ganglion neurons were decreased in all specimens (versus normative data). Conclusions In our study, CHARGE syndrome was associated with multiple TB abnormalities that may severely affect audiovestibular function and rehabilitation.

scholarly journals Supratubal recess and sinus tympani: CT analysis of middle ear hidden areas

2019 ◽  
Vol 50 (1) ◽  
Author(s):  
Mohammad Waheed El-Anwar ◽  
Diaa Bakry Eldib ◽  
Ashraf Elmalt ◽  
Alaa Omar Khazbak
Keyword(s):  
Middle Ear ◽  
Preoperative Imaging ◽  
High Resolution Computed Tomography ◽  
Sinus Tympani ◽  
Ct Analysis ◽  
Length Width ◽  
Middle Ear Anatomy ◽  
Grade 3 ◽  
Temporal Bones ◽  
Ct Classification

Abstract Background High-resolution computed tomography (HRCT) magnifies the role of preoperative imaging for detailed middle ear anatomy particularly its hidden area. The purpose of the current study was to assess the sinus tympani (ST) and supratubal recess (STR) by HRCT, to create CT classification of the STR depth, and to study the relationship between ST types and the new STR grades. Results In HRCT of non-pathological temporal bones of 100 subjects (200 ears), measurements of the STR and ST were calculated, registered, and analyzed. The depth of the STR was classified into grade 1 with depth less than 3 mm, grade 2 with depth ranged between 3 and 5 mm, and grade 3 with depth more than 5 mm. The mean STR length, width, and height were 4.17 ± 0.86, 3.55 ± 0.65, and 3.64 ± 0.7 mm, respectively, while the ST mean length and width of were 2.52 ± 0.5 and 1.82 ± 0.78 mm, respectively, without significant differences between either sexes or sided. The ST types were found to be type A in 56 ears (28%), type B in 142 ears (71%), and type C in 2 ears (1%). The STR grading was grade 1 in 12 ears (6%), grade 2 in 160 ears (80%), and grade 3 in 28 ears (14%) without significant relationship between ST types and STR grading (P = 0.3). Conclusion The current study provided reliable and applicable methods of CT assessment of STR and ST that can help to predict the degree of surgical visibility of the ST and STR during ear surgery.

Tympanometry Revealing Middle Ear Pathology

1976 ◽  
Vol 85 (2_suppl) ◽  
pp. 209-215 ◽  
Author(s):  
Ulf Renvall ◽  
Jörgen Holmquist
Keyword(s):  
Middle Ear ◽  
Pure Tone ◽  
Screening Method ◽  
Initial Study ◽  
Predisposing Factor ◽  
Pilot Studies ◽  
Impedance Audiometry ◽  
Middle Ear Pressure ◽  
Stapedius Reflex ◽  
Temporal Bones

In order to evaluate the usefulness of impedance audiometry as a screening method for school children, two different pilot studies were performed. The results indicated that impedance audiometry (tympanometry and stapedius reflex test) was more efficient than otoscopy and pure tone screening in the detection of ears with secretory otitis media (SOM). In order to gain some more experience, an extended study of 800 7-year-olds was performed. The results from this investigation showed 6.5% pathological values with pure tone screening, 13.5% pathological values with tympanometry and 32% elevated or nonelicitable stapedius reflexes. Analysis of our observations indicates that the stapedius reflex may be too sensitive a test to be used as a screening method. Tympanometry, however, is recommended as a complement to pure tone screening in screening of children. A 6–12 months follow-up was also performed on 357 ears in which an initial study had shown a middle ear pressure of ≤ −100 mm H2O. At the repeated test 20% had pathological pure tone screening, 40% had a middle ear pressure of ≤ −100 mm H2O, 57% had elevated or nonelicitable stapedius reflexes, and 14% had middle ear effusion. The high frequency of persisting abnormal middle ear pressure and effusion in these 357 ears suggests that a middle ear pressure of ≤ −100 mm H2O can be a predisposing factor for SOM. In an experimental study on human temporal bones it was demonstrated that the tympanogram preserves its original appearance when the water level is low in the middle ear, while a higher level gives rise to a pathological tympanogram. It is also demonstrated that there is a discrepancy between the tympanometrically, indirectly recorded middle ear pressure and the middle ear pressure as measured manometrically, directly from the middle ear.

scholarly journals Transcanal Endoscopic Antrostomy Hole : Its Utility in Restoring Ventilation Pathway to Epitympanum and Mastoid Antrum During Tympanoplasty

2014 ◽  
Vol 2 (1) ◽  
pp. 9-14
Author(s):  
Sheikh Shawkat Kamal
Keyword(s):  
Middle Ear ◽  
Tertiary Care ◽  
Case Series ◽  
Care Hospital ◽  
Retrospective Case ◽  
Middle Ear Mucosa ◽  
Case Series Study ◽  
Temporal Bones ◽  
Mastoid Antrum

Aim: To evaluate the role of newly created transcanal endoscopic antrostomy hole as a passage in restoring the aeration of epitympanum and mastoid antrum.Materials & Methods: Study design: Retrospective case series study. Study duration: From January 2013 to January 2014. Study place: Private tertiary care hospital. Patients: 27  ears of 23 adult patients (age ranging from 15years to 54years) underwent transcanal endoscopic tympanoplasty for their chronic middle ear diseases in presence of inflamed middle ear mucosa along with radiological shadows of stagnant fluid in their epitympanum and mastoid antrum. Structured three months follow-up was ensured in every case. Intervention: A hole was created at a selected site of posterior meatal wall purely through transcanal endoscopic approach that established direct communication between mastoid antrum and external auditory canal. Thereafter this newly created passage was used for three purposes- assessment of the condition of mastoid antrum, performing the water test for checking epitympanic patency and in few cases placement of temporary tube for postoperative ventilation and drainage of middle ear. Main out come measures: The feasibility, performance and management of transcanal endoscopic antrostomy hole as passage for reestablishing the aeration of epitympanum and mastoid antrum.Results: The chosen site for antrostomy hole was found effective and safe in providing convenient entrance into the mastoid antrum in every case in this study with out facing technical complexity and failure. Postoperative healing of skin over antrostomy hole was found complete in all ears without any inward growth of skin in to mastoid antrum. Available post operative CT scan imaging of temporal bones showed improved aeration in their epitympanum and mastoid antrum.Conclusions: The role of transcanal antrostomy hole has been proved worthy in restoring ventilation pathway to epitympanum and mastoid antrum during tympanoplasty. This antrostomy hole has the potentiality to be considered in future for placement of long term mastoid ventilation tube in order to treat persistent atelectatic middle ear.

scholarly journals Comparative Characteristics of Bone-Plastic Materials for Mastoidoplasty

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Roman Reznikov
Keyword(s):  
Composite Materials ◽  
Bone Tissue ◽  
Middle Ear ◽  
Open Type ◽  
Plastic Materials ◽  
Temporal Bones ◽  
Tricalcium Phosphates

The paper presents the results of the comparative characteristics of the use of various bone-plastic materials for mastoidoplasty. The study included 30 patients who underwent an open-type sanitizing operation with mastoidoplasty with osteoplastic materials. When comparing drugs, the following criteria were used: 1) convenience of modeling the material; 2) the course of the wound process; 3) osseointegration - the process of formation of "new bone tissue (CT of the temporal bones 6 and 12 months). As a result, it was confirmed that the samples of the main groups of bone replacements studied by us. preparations (biositalls, composite materials and β- tricalcium phosphates) can be successfully used in mastoidoplasty after open types of sanitizing operations on the middle ear.

3D Finite Element Modeling of Blast Wave Transmission From the External Ear to a Spiral Cochlea

2021 ◽  
Author(s):  
Marcus Brown ◽  
John Bradshaw ◽  
Rong Z. Gan
Keyword(s):  
Finite Element ◽  
Middle Ear ◽  
Basilar Membrane ◽  
Transverse Motion ◽  
Fe Model ◽  
Ear Canal ◽  
Blast Overpressure ◽  
Stapes Footplate ◽  
Human Ear ◽  
Temporal Bones

Abstract Blast-induced injuries affect the health of veterans, in which the auditory system is often damaged, and blast-induced auditory damage to the cochlea is difficult to quantify. A recent study modeled blast overpressure (BOP) transmission throughout the ear utilizing a straight, two-chambered cochlea, but the spiral cochlea's response to blast exposure has yet to be investigated. In this study, we utilized a human ear finite element (FE) model with a spiraled, two-chambered cochlea to simulate the response of the anatomical structural cochlea to BOP exposure. The FE model included an ear canal, middle ear, and two and half turns of two-chambered cochlea and simulated a BOP from the ear canal entrance to the spiral cochlea in a transient analysis utilizing fluid-structure interfaces. The model's middle ear was validated with experimental pressure measurements from the outer and middle ear of human temporal bones. The results showed high stapes footplate displacements up to 28.5µm resulting in high intracochlear pressures and basilar membrane (BM) displacements up to 43.2µm from a BOP input of 30.7kPa. The cochlea's spiral shape caused asymmetric pressure distributions as high as 4kPa across the cochlea's width and higher BM transverse motion than that observed in a similar straight cochlea model. The developed spiral cochlea model provides an advancement from the straight cochlea model to increase the understanding of cochlear mechanics during blast and progresses towards a model able to predict potential hearing loss after blast.

scholarly journals Comparative study of efficiency and characteristics of FMT and DRT installed in human cadavers for round-window stimulation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dong Ho Shin ◽  
Jong Hoon Kim ◽  
Peter Gottlieb ◽  
Yona Vaisbuch ◽  
Sunil Puria ◽  
...  
Keyword(s):  
Middle Ear ◽  
Hearing Aids ◽  
Round Window ◽  
Standard Of Care ◽  
Acoustic Hearing ◽  
Middle Ear Implants ◽  
Human Cadavers ◽  
Limited Frequency ◽  
Output Characteristics ◽  
Temporal Bones

AbstractAcoustic hearing aids generate amplified sound in the ear canal, and they are the standard of care for patients with mild to moderate sensorineural hearing loss. However, because of their limited frequency bandwidth, gain, and feedback, there is substantial room for improvement. Active middle ear implants, which directly vibrate the middle ear and cochlea, are an alternative approach to conventional acoustic hearing aids. They provide an opportunity to improve sound quality and speech understanding with amplification rehabilitation. For floating-mass type and direct-rod type (DRT) middle ear transducers, a differential floating-mass transducer (DFMT) and a tri-coil bellows transducer (TCBT), respectively, were fabricated to measure the output characteristics in four human temporal bones. Both were fabricated to have similar output forces per unit input and were placed in four human temporal bones to measure their output performances. The TCBT resulted in higher output than did the DFMT throughout the audible frequency range, and the output was more prominent at lower frequency ranges. In this study, we showed that DRT was a more effective method for round window stimulation. Because of its frequency characteristics and vibration efficiency, this implantation method can be utilized as a driving solution for middle ear implants.

Mechanical stress-induced reactive gliosis in the auditory nerve and cochlear nucleus

2011 ◽  
Vol 114 (2) ◽  
pp. 414-425 ◽  
Author(s):  
Tetsuji Sekiya ◽  
Masahiro Matsumoto ◽  
Ken Kojima ◽  
Kazuya Ono ◽  
Yayoi S. Kikkawa ◽  
...  
Keyword(s):  
Mechanical Stress ◽  
Cochlear Nucleus ◽  
Auditory Nerve ◽  
Auditory Brainstem ◽  
Reactive Gliosis ◽  
Auditory Pathways ◽  
Microsurgical Treatment ◽  
Auditory Nerves ◽  
Brainstem Response ◽  
Temporal Bones

Object Hearing levels following microsurgical treatment gradually deteriorate in a number of patients treated for vestibular schwannoma (VS), especially in the subacute postoperative stage. The cause of this late-onset deterioration of hearing is not completely understood. The aim of this study was to investigate the possibility that reactive gliosis is a contributory factor. Methods Mechanical damage to nerve tissue is a feature of complex surgical procedures. To explore this aspect of VS treatment, the authors compressed rat auditory nerves with 2 different degrees of injury while monitoring the compound action potentials of the auditory nerve and the auditory brainstem responses. In this experimental model, the axons of the auditory nerve were quantitatively and highly selectively damaged in the cerebellopontine angle without permanent compromise of the blood supply to the cochlea. The temporal bones were processed for immunohistochemical analysis at 1 week and at 8 weeks after compression. Results Reactive gliosis was induced not only in the auditory nerve but also in the cochlear nucleus following mechanical trauma in which the general shape of the auditory brainstem response was maintained. There was a substantial outgrowth of astrocytic processes from the transitional zone into the peripheral portion of the auditory nerve, leading to an invasion of dense gliotic tissue in the auditory nerve. The elongated astrocytic processes ran in parallel with the residual auditory neurons and entered much further into the cochlea. Confocal images disclosed fragments of neurons scattered in the gliotic tissue. In the cochlear nucleus, hypertrophic astrocytic processes were abundant around the soma of the neurons. The transverse diameter of the auditory nerve at and proximal to the compression site was considerably reduced, indicating atrophy, especially in rats in which the auditory nerve was profoundly compressed. Conclusions The authors found for the first time that mechanical stress to the auditory nerve causes substantial reactive gliosis in both the peripheral and central auditory pathways within 1–8 weeks. Progressive reactive gliosis following surgical stress may cause dysfunction in the auditory pathways and may be a primary cause of progressive hearing loss following microsurgical treatment for VS.

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