scholarly journals Diagnostic Value of 3D Segmentation in Understanding the Anatomy of Human Inner Ear Including Malformation Types

2020 ◽  
pp. 014556132090662
Author(s):  
Saad Alenzi ◽  
Anandhan Dhanasingh ◽  
Hani Alanazi ◽  
Abdulrahman Alsanosi ◽  
Abdulrahman Hagr
Keyword(s):  
Inner Ear ◽  
Three Dimensional ◽  
Internal Auditory Canal ◽  
B Value ◽  
Data Sets ◽  
Type Ii ◽  
3D Segmentation ◽  
Training Tool ◽  
A Value ◽  
Human Inner Ear

Objective: To understand the anatomical and dimensional variations of the human inner ear using 3-dimensional (3D) segmentation within the Middle East population. Design: Retrospective study. Setting: King Abdullah Ear Specialist Center (KAESC) Riyadh, Saudi Arabia. Participant: Forty computed tomography (CT) images of patients with sensorineural hearing loss who underwent cochlear implant (CI) were taken for analysis. Main outcome Measures: Three-dimensional images showing the anatomical variations of the inner ear including various pathological conditions, cochlear parameters including basal turn diameter (“A” value), “B” value which is perpendicular to “A” value, cochlear height, length, and width of the internal auditory canal (IAC), intercochlear spacing, and electrode angular insertion depth (AID). Results: Out of 40 CT image data sets, 12 had normal inner-ear anatomy (NA), 4 with enlarged vestibular aqueduct syndrome (EVAS), 8 with only 2 turns of the cochlea (2TL), 7 with incomplete partition (IP) type II, 5 with cochlear hypoplasia, 1 with common cavity, and 3 with abnormal IAC. Taking the NA, EVAS, 2TL, and the IP type II cases altogether, age of the patient had no correlation with the “A” value; however, the “A” value had a linear correlation with the “B” value. The age of the patient had an increasing logarithmic correlation with the IAC length and the intercochlear spacing. The “A” value did not have any meaningful correlation with the cochlear height. Three data sets showed asymmetric inner-ear malformation types on either side of the ears. All these 40 cases were implanted with various CI electrode array variants and the corresponding postoperative plain film X-ray images showing the electrode AID are given separately in figures. Conclusions: Three-dimensional segmentation of the inner ear from the temporal bone CT is a valuable clinical and training tool for surgeons and radiologists especially in difficult cases which will certainly help to understand the overall anatomical and dimensional variations.

scholarly journals Shape of the Cochlear Basal Turn: An Indicator for an Optimal Electrode-to-Modiolus Proximity With Precurved Electrode Type

2020 ◽  
Vol 100 (1) ◽  
pp. 38-43
Author(s):  
Tawfiq Khurayzi ◽  
Anandhan Dhanasingh ◽  
Fida Almuhawas ◽  
Abdurrahman Alsanosi
Keyword(s):  
Three Dimensional ◽  
Electrode Array ◽  
Image Data ◽  
B Value ◽  
Data Sets ◽  
Basal Turn ◽  
A Value ◽  
Preoperative Image ◽  
Parameters Measurement ◽  
Positive Linear Relation

Objective: The objective of this study was to determine the shape of cochlear basal turn through basic cochlear parameters measurement. The secondary aim was to overlay an image of the precurved electrode array on top of the three-dimensional (3D) image of the cochlea to determine which shape of the cochlear basal turn gives optimal electrode-to-modiolus proximity. Materials and Methods: Computed tomography (CT) preoperative image-data sets of 117 ears were made available for the measurements of cochlear parameters retrospectively. Three-dimensional slicer was used in the visualization and measurement of cochlear parameters from both 3D and 2D (2-dimensional) images of the inner ear. Cochlear parameters including basal turn diameter ( A), width of the basal turn ( B), and cochlear height (H) were measured from the appropriate planes. B/ A ratio was made to investigate which ratios correspond to round and elliptical shape of the cochlear basal turn. Results: The cochlear size as measured by A value ranged between 7.4 mm and 10 mm. The B value and the cochlear height ( H) showed a weak positive linear relation with A value. The ratio between the B and A values anything above or below 0.75 could be an indicator for a more round- or elliptical shaped cochlear basal turn, respectively. One sized/shaped commercially available precurved electrode array would not offer a tight electrode-to-modiolus in the cochlea that has an elliptical shaped basal turn as identified by the B/A ratio of <0.75. Conclusion: Accurate measurement of cochlear parameters adds value to the overall understanding of the cochlear geometry before a cochlear implantation procedure. The shape of cochlear basal turn could have clinical implications when comes to electrode-to-modiolus proximity.

scholarly journals Direct SARS-CoV-2 infection of the human inner ear may underlie COVID-19-associated audiovestibular dysfunction

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Minjin Jeong ◽  
Karen E. Ocwieja ◽  
Dongjun Han ◽  
P. Ashley Wackym ◽  
Yichen Zhang ◽  
...  
Keyword(s):  
Inner Ear ◽  
Hair Cells ◽  
Molecular Mechanisms ◽  
Three Dimensional ◽  
Induced Pluripotent Stem Cell ◽  
In Vitro Models ◽  
Cellular Models ◽  
Induced Pluripotent ◽  
Human Inner Ear

Abstract Background COVID-19 is a pandemic respiratory and vascular disease caused by SARS-CoV-2 virus. There is a growing number of sensory deficits associated with COVID-19 and molecular mechanisms underlying these deficits are incompletely understood. Methods We report a series of ten COVID-19 patients with audiovestibular symptoms such as hearing loss, vestibular dysfunction and tinnitus. To investigate the causal relationship between SARS-CoV-2 and audiovestibular dysfunction, we examine human inner ear tissue, human inner ear in vitro cellular models, and mouse inner ear tissue. Results We demonstrate that adult human inner ear tissue co-expresses the angiotensin-converting enzyme 2 (ACE2) receptor for SARS-CoV-2 virus, and the transmembrane protease serine 2 (TMPRSS2) and FURIN cofactors required for virus entry. Furthermore, hair cells and Schwann cells in explanted human vestibular tissue can be infected by SARS-CoV-2, as demonstrated by confocal microscopy. We establish three human induced pluripotent stem cell (hiPSC)-derived in vitro models of the inner ear for infection: two-dimensional otic prosensory cells (OPCs) and Schwann cell precursors (SCPs), and three-dimensional inner ear organoids. Both OPCs and SCPs express ACE2, TMPRSS2, and FURIN, with lower ACE2 and FURIN expression in SCPs. OPCs are permissive to SARS-CoV-2 infection; lower infection rates exist in isogenic SCPs. The inner ear organoids show that hair cells express ACE2 and are targets for SARS-CoV-2. Conclusions Our results provide mechanistic explanations of audiovestibular dysfunction in COVID-19 patients and introduce hiPSC-derived systems for studying infectious human otologic disease.

scholarly journals Three Dimensional Reconstruciton of the Human Inner Ear by Magnetic Resonance Imaging

1991 ◽  
Vol 50 (Suppl-7) ◽  
pp. 75-77
Author(s):  
Ritsu Seo ◽  
Izumi Koizuka ◽  
Mitsuhito Sano ◽  
Toru Matsunaga ◽  
Yoshiteru Seo ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Inner Ear ◽  
Three Dimensional ◽  
Resonance Imaging ◽  
Human Inner Ear

An Approach for Precise Three-Dimensional Modeling of the Human Inner Ear

ORL ◽  
2006 ◽  
Vol 68 (5) ◽  
pp. 302-310 ◽  
Author(s):  
Shu-Feng Li ◽  
Tian-Yu Zhang ◽  
Zheng-Min Wang
Keyword(s):  
Inner Ear ◽  
Three Dimensional ◽  
Three Dimensional Modeling ◽  
Dimensional Modeling ◽  
Human Inner Ear

scholarly journals The b-value of the Kelud Volcano in the Last Three Decades

2021 ◽  
Vol 325 ◽  
pp. 01019
Author(s):  
Sintia Windhi Niasari ◽  
Lusia Rita Nugraheni ◽  
Puspita Dian Maghfira
Keyword(s):  
Explosive Eruption ◽  
Total Population ◽  
B Value ◽  
Data Sets ◽  
Tourist Destination ◽  
Effusive Eruption ◽  
A Value ◽  
Hazard Risk ◽  
Seismicity Monitoring

Kelud volcano is located in the Kediri sub-district, East Java Province, Indonesia. This volcano is still active, with total population, in the radius of 10 km, is around 10 thousand people. Kelud volcano is a popular tourist destination. On the weekend, total visitor can reach 5,000 people per-day. These people are at high risk when the Kelud volcano erupts. The last eruption of the Kelud volcano occurred in 2014 and was explosive eruption. Previously, there was an effusive eruption in 2007. These two types of eruption have its own geo hazard risk. Thus, predict the eruption type could help hazard mitigation. In this study, two data sets of earthquakes, 1990-2007 and 2008-2020, were analysed to determine the b-value and its relationship to the eruption type of the Kelud volcano. The calculation of the b-value uses the Gutenberg-Richter relationship. Calculation of the b-value in 2007, when there was an effusive eruption, showed a value of 2.27, while in 2014 (when there was an explosive eruption) was 1.85. After 2009, the curve of the b-value against time shows decrease. As a long term precursor of the Kelud activity, this b-value curve should be analysed continuously, besides volcano tectonic seismicity monitoring.

scholarly journals A novel method of identifying inner ear malformation types by pattern recognition in the mid modiolar section

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anandhan Dhanasingh ◽  
Daniel Erpenbeck ◽  
Masoud Zoka Assadi ◽  
Úna Doyle ◽  
Peter Roland ◽  
...  
Keyword(s):  
Inner Ear ◽  
Internal Auditory Canal ◽  
Type I ◽  
Side View ◽  
Outer Contour ◽  
Vestibular Aqueduct ◽  
A Value ◽  
Straight Line ◽  
Line Parallel ◽  
Inner Ear Malformation

AbstractIdentification of the inner ear malformation types from radiographs is a complex process. We hypothesize that each inner ear anatomical type has a uniqueness in its appearance in radiographs. The outer contour of the inner ear was captured from the mid-modiolar section, perpendicular to the oblique-coronal plane, from which the A-value was determined from CT scans with different inner ear anatomical types. The mean A-value of normal anatomy (NA) and enlarged vestibular aqueduct syndrome (EVAS) anatomical types was greater than for Incomplete Partition (IP) type I, II, III and cochlear hypoplasia. The outer contour of the cochlear portion within the mid-modiolar section of NA and EVAS resembles the side view of Aladdin’s lamp; IP type I resembles the side-view of the Sphinx pyramid and type II a Pomeranian dog’s face. The steep spiraling cochlear turns of IP type III resemble an Auger screw tip. Drawing a line parallel to the posterior margin of internal auditory canal (IAC) in axial-view, bisecting the cavity into cochlear and vestibular portions, identifies common-cavity; whereas a cavity that falls under the straight-line leaving no cochlear portion identifies cochlear aplasia. An atlas of the outer contour of seventy-eight inner ears was created for the identification of the inner malformation types precisely.

Computer-aided methods for 3-D visualization of serial sections and thick biological specimens

1992 ◽  
Vol 50 (2) ◽  
pp. 1060-1061
Author(s):  
Mark Ellisman ◽  
Maryann Martone ◽  
Gabriel Soto ◽  
Eleizer Masliah ◽  
David Hessler ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Three Dimensional ◽  
Neuritic Plaque ◽  
Dimensional Structure ◽  
Data Sets ◽  
Molecular Physiology ◽  
Research Activities ◽  
Computer Aided ◽  
Dimensional Reconstruction

Structurally-oriented biologists examine cells, tissues, organelles and macromolecules in order to gain insight into cellular and molecular physiology by relating structure to function. The understanding of these structures can be greatly enhanced by the use of techniques for the visualization and quantitative analysis of three-dimensional structure. Three projects from current research activities will be presented in order to illustrate both the present capabilities of computer aided techniques as well as their limitations and future possibilities.The first project concerns the three-dimensional reconstruction of the neuritic plaques found in the brains of patients with Alzheimer's disease. We have developed a software package “Synu” for investigation of 3D data sets which has been used in conjunction with laser confocal light microscopy to study the structure of the neuritic plaque. Tissue sections of autopsy samples from patients with Alzheimer's disease were double-labeled for tau, a cytoskeletal marker for abnormal neurites, and synaptophysin, a marker of presynaptic terminals.

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