Three-Dimensional High-Resolution Temporal Bone Histopathology Identifies Areas of Vascular Vulnerability in the Inner Ear

Objectives: Hypothesized causes of vestibular neuritis/labyrinthitis include neuroinflammatory or vascular disorders, yet vascular disorders of the inner ear are poorly understood. Guided by known microvascular diseases of the retina, we developed 2 hypotheses: (1) there exist vascular vulnerabilities of artery channels in cases of hypothetical nerve swelling for the superior, inferior, and vestibulocochlear artery and (2) there are arteriovenous crossings that could compromise vascular flow in disease states. Methods: Two fully mounted and stained temporal bones were used to render three-dimensional reconstructions of the labyrinth blood supply. Using these maps, areas of potential vascular compression were quantified in 50 human temporal bones. Results: Although inner ear arteries and veins mostly travel within their own bony channels, they may be exposed (1) at the entrance into the otic capsule, and (2) where the superior vestibular vein crosses the inferior vestibular artery. At the entry into the otic capsule, the ratio of the soft tissue to total space for the superior vestibular artery was significantly greater than the inferior vestibular artery/cochleovestibular artery (median 44, interquartile range 34–55 vs. 14 [9–17], p < 0.0001). Conclusions: Three-dimensional reconstruction of human temporal bone histopathology can guide vascular studies of the human inner ear. Studies of retinal microvascular disease helped identify areas of vascular vulnerability in cases of hypothetical nerve swelling at the entrance into the otic capsule and at an arteriovenous crossing near the saccular macula. These data may help explain patterns of clinical findings in peripheral vestibular lesions.

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X-ray microtomography study of otic capsule deficiencies: three-dimensional modelling of the fissula ante fenestram

The Journal of Laryngology & Otology ◽

10.1017/s0022215115001607 ◽

2015 ◽

Vol 129 (9) ◽

pp. 840-851 ◽

Cited By ~ 1

Author(s):

J W Lee ◽

P Sale ◽

N P Patel

Keyword(s):

Inner Ear ◽

Three Dimensional ◽

Oval Window ◽

Otic Capsule ◽

X Ray ◽

Otologic Surgery ◽

Science Group ◽

Temporal Bones ◽

The Relationship ◽

Non Destructive

AbstractBackground:The postulated sites of perilymph fistulae involve otic capsule deficiencies, in particular, at the fissula ante fenestram. Histological studies have revealed this to be a channel extending from the middle ear, and becoming continuous with the inner ear medial to the anterior limit of the oval window. The relationship between a patent fissula and symptoms of perilymph fistula is contentious.Objective:The understanding of the anatomy of the fissula ante fenestram is incomplete. Histopathology is inherently destructive to the delicate ultrastructure of the middle and inner ear. Conversely, X-ray microtomography allows non-destructive examination of the otic capsule. In this study, we used X-ray microtomography to characterise the fissula ante fenestram.Materials and methods:We imaged cadaveric temporal bones with X-ray microtomography. We used the Avizo Fire (Visualization Science Group, Merignac Cedex, France) software to perform post-processing and image analysis.Results:Three-dimensional modelling of the fissula ante fenestram allowed stratification into four forms: rudimentary pit; partial fissula; complete occluded fissula; and complete patent fissula.Conclusion:X-ray microtomography showed that the fissula ante fenestram is present in various forms from rudimentary pit to complete deficiency of the otic capsule. This understanding may have implications for otologic surgery and clinical diagnosis of perilymph fistula.

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Reproducibility of Volumetric Assessment of the Inner Ear Using Three Dimensional Reconstruction of the High Resolution MR Sequence

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405613666170331104444 ◽

2018 ◽

Vol 14 (4) ◽

pp. 582-586

Author(s):

Nagy N.N. Naguib ◽

Ahmed M. Emam ◽

Tatjana Gruber-Rouh ◽

Marc Harth ◽

Renate Hammersting ◽

...

Keyword(s):

High Resolution ◽

Inner Ear ◽

Three Dimensional ◽

Three Dimensional Reconstruction ◽

Volumetric Assessment ◽

Dimensional Reconstruction

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The Effect of Pulling Out Cochlear Implant Electrodes on Inner Ear Microstructures: A Temporal Bone Study

International Journal of Otolaryngology ◽

10.1155/2011/107176 ◽

2011 ◽

Vol 2011 ◽

pp. 1-4 ◽

Cited By ~ 2

Author(s):

Ingo Todt ◽

Rainer O. Seidl ◽

Arne Ernst

Keyword(s):

Cochlear Implant ◽

Inner Ear ◽

Temporal Bone ◽

Basilar Membrane ◽

Temporal Sequence ◽

Pull Out ◽

Temporal Bones

The exchange of an cochlear implant or the re-positioning of an electrode have become more frequently required than a decade ago. The consequences of such procedures at a microstructural level within the cochlea are not known. It was the aim of the present study to further investigate the effects of an CI electrode pull-out. Therefore 10 freshly harvested temporal bones (TB) were histologically evaluated after a cochlear implant electrode pull-out of a perimodiolar electrode. In additional 9 TB the intrascalar movements of the CI electrode while being pulled-out were digitally analysed by video- capturing. Histologically, a disruption of the modiolar wall or the spiral osseous lamina were not observed. In one TB, a basilar membrane lifting up was found, but it could not be undoubtedly attributed to the pull-out of the electrode. When analyzing the temporal sequence of the electrode movement during the pull-out, the electrode turned in one case so that the tip elevates the basilar membrane. The pull- out of perimodiolarly placed CI electrodes does not damage the modiolar wall at a microstructural level and should be guided (e.g., forceps) to prevent a 90 o turning of the electrode tip into the direction of the basilar membrane.

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Three-Dimensional Reconstruction of C57BL/6 Mouse Inner Ear during Development

ORL ◽

10.1159/000272029 ◽

2009 ◽

Vol 71 (6) ◽

pp. 334-341 ◽

Cited By ~ 1

Author(s):

Fang-Lu Chi ◽

Zhao Han ◽

Pei-Dong Dai ◽

Yi-Bo Huang ◽

Ning Cong ◽

...

Keyword(s):

Inner Ear ◽

Three Dimensional ◽

Three Dimensional Reconstruction ◽

Dimensional Reconstruction

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Narrowest (ISTHMUS) Portion of Eustachian Tube: A Computer-Aided Three-Dimensional Reconstruction and Measurement Study

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949710600710 ◽

1997 ◽

Vol 106 (7) ◽

pp. 583-588 ◽

Cited By ~ 42

Author(s):

Masaharu Sudo ◽

Isamu Sando ◽

Akihiro Ikui ◽

Chiaki Suzuki

Keyword(s):

Eustachian Tube ◽

Middle Ear ◽

Three Dimensional ◽

Three Dimensional Reconstruction ◽

Cross Sectional ◽

Computer Aided ◽

Dimensional Reconstruction ◽

Tensor Veli Palatini Muscle ◽

Normal Human ◽

Temporal Bones

Nine normal human temporal bones from persons 16 to 88 years old were studied by computer aided three-dimensional reconstruction and measurement. The length of the eustachian tube (ET) lumen in three portions (from pharyngeal orifice to tympanic orifice: cartilaginous, junctional, and bony) averaged 23.6 ±4.3 mm, 3.0 ± 1.9 mm, and 6.4 ± 2.6 mm. The narrowest portion of the ET lumen was in the cartilaginous portion in all cases: 20.5 ± 4.2 mm from the pharyngeal orifice and 3.1 ± 1.6 mm from the pharyngeal margin of the junctional portion. The cross-sectional area of the narrowest portion was 0.65 ± 0.2 mm2. The tendon of the tensor veli palatini muscle (TVPM) inserted into the lateral lamina in the narrowest portion of the ET lumen in five of nine cases. These results suggest that contraction of the TVPM opens the narrowest portion of the ET lumen to ventilate the middle ear and that this portion also plays a role in protecting the middle ear.

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Temporal bone Pneumatization in Otosclerosis

Otolaryngology ◽

10.1016/j.otohns.2008.09.004 ◽

2008 ◽

Vol 139 (6) ◽

pp. 850-853 ◽

Cited By ~ 1

Author(s):

Daniel T. Ganc ◽

Robert W. Jyung

Keyword(s):

Temporal Bone ◽

Statistical Significance ◽

Three Dimensional ◽

Neck Surgery ◽

Adult Patients ◽

Control Group ◽

Test Analysis ◽

Temporal Bone Pneumatization ◽

History Of ◽

Temporal Bones

Objectives To determine whether there is a difference in the pneumatization of temporal bones with otosclerosis versus normal temporal bones. Methods A retrospective study of 46 ears from 24 adult patients with otosclerosis and 64 ears from 47 adult patients in a control group. The study group included temporal bone CT scans available from patients with otosclerosis. The control group consisted of patients who had temporal bone CTs for reasons likely unrelated to a history of middle ear disease. Data were obtained with a virtual reality system that allows three-dimensional manipulation and analysis. Results The temporal bone pneumatization for the otosclerosis group was 4.82 ± 2.27 cm3 vs 6.06 ± 2.71 cm3 for the control group. Two-sample t test analysis revealed no statistical significance ( P = 0.059) between pneumatization in the control vs otosclerosis groups. Conclusion There is no difference in temporal bone pneumatization between patients with otosclerosis and a control population. Therefore, temporal bone pneumatization by itself is not an adequate explanation for the apparent protective effect of otosclerosis against otitis media. © 2008 American Academy of Otolaryngology-Head and Neck Surgery Foundation. All rights reserved.

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Computer-Aided Three-Dimensional Reconstruction and Measurement of the round Window and its Membrane

Otolaryngology ◽

10.1177/019459988910100501 ◽

1989 ◽

Vol 101 (5) ◽

pp. 517-521 ◽

Cited By ~ 15

Author(s):

Haruo Takahashi ◽

Akira Takagi ◽

Isamu Sando

Keyword(s):

Surface Area ◽

Round Window ◽

Three Dimensional ◽

Round Window Membrane ◽

Reconstruction Method ◽

Three Dimensional Reconstruction ◽

Maximal Diameter ◽

Computer Aided ◽

Dimensional Reconstruction ◽

Temporal Bones

This study was performed to clarify the complex three-dimensional shape of the round window and its membrane, and to measure these structures by using the computer-aided three-dimensional reconstruction method we developed. The equipment used included a personal computer, a high-resolution, 14-Inch color monitor, and a digitizer. Materials consisted of five normal temporal bones obtained from five individuals with negative otologic histories who had been 5 months and 14, 15, 18, and 59 years old at death. Round window membranes were found to be convex to the middle ear side when viewed in the coronal plane, but to be concave when viewed in the sagittal plane; thus the membrane in most cases seemed to be shaped like a saddle, tapered toward the vestibular end. The average maximal diameter, sagittal length, horizontal width, and surface area of the round window were 2.32 ± 0.19 mm, 2.08 ± 0.22 mm, 1.76 ± 0.10 mm, and 2.70 ± 0.43 mm2, respectively. The average surface area of the round window membrane was 2.98 ± 0.43 mm2.

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Three-Dimensional Reconstruction and Measurement Study of Human Eustachian Tube Structures: A Hypothesis of Eustachian Tube Function

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949810700701 ◽

1998 ◽

Vol 107 (7) ◽

pp. 547-554 ◽

Cited By ~ 28

Author(s):

Masaharu Sudo ◽

Isamu Sando ◽

Chiaki Suzuki

Keyword(s):

Eustachian Tube ◽

Three Dimensional ◽

Lymphoid Tissues ◽

Reconstruction Method ◽

Eustachian Tube Function ◽

Three Dimensional Reconstruction ◽

Inferior Margin ◽

Dimensional Reconstruction ◽

Tube Function ◽

Temporal Bones

Histologic sections from nine temporal bones with eustachian tubes (ETs) attached were analyzed with a computer-aided three-dimensional reconstruction method to determine the curvature and tilt of the ET and the anatomic relationships between the medial lamina of the ET cartilage, the levator veli palatini muscle (LVPM), and Rosenmüller's fossa. It was found that the ET is convex superomedially and is tilted medially. The LVPM is located inferolateral to the inferior margin of the medial lamina of the anterior ET cartilage. The LVPM is inferior to the medial lamina of the posterior ET cartilage. These findings suggest that the LVPM opens the anterior cartilaginous portion of the ET by rotating the medial lamina with increased dimension of the muscle body when it contracts. Rosenmüller's fossa extends along the ET with rich lymphoid tissues as far as approximately one half the total length of the ET and very close to the skull base.

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Impact of temporal bone dissection on the understanding anatomy of the ear among medical students

International Journal of Otorhinolaryngology and Head and Neck Surgery ◽

10.18203/issn.2454-5929.ijohns20184365 ◽

2018 ◽

Vol 4 (6) ◽

pp. 1489

Author(s):

K. C. Prasad ◽

Prathyusha K. ◽

Shreeharsha Maruvala ◽

Harshita T. R. ◽

Indu Varsha Gopi ◽

...

Keyword(s):

Medical Students ◽

Temporal Bone ◽

Three Dimensional ◽

Operative Procedures ◽

Research Centre ◽

Medical College ◽

Group I ◽

Group Ii ◽

Temporal Bones ◽

The Impact

The aim was to study the impact of temporal bone dissection demonstrations on understanding anatomy of the ear among medical students. During a period of six months from October 2017 to March 2018, 10 cadaveric temporal bones dissections were demonstrated using ZEISS microscope and in the presence of medical students headed by a Consultant Otolaryngologist in the department of ENT, Sri Devaraj URS Medical College and Research Centre, Kolar. Anatomy of the middle ear and inner ear and various operative procedures were demonstrated. The students were divided into 2 groups. Group I comprised students who attended the temporal bone dissection and Group II included those who didn’t attend dissection. After the session both the groups were assessed by the consultant. Scores were given to the group individuals based on the ability to answer the questions. 10 Temporal bone dissections were demonstrated in 6 months period to medical students who were divided into 2 groups based on their attendance of the demonstration. The students of both groups were assessed. Scores were given by Likert scale-5point scale question. The results of our study proved that those students who attended the temporal bone dissection (Group-I) had better understanding of the anatomy and operative procedures of the ear as compared to students in group II. Demonstration of temporal bone dissection to the medical students had a good impact on their understanding of the three dimensional anatomy of the ear.

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