The semicircular canals

1983 ◽  
pp. 86-86
Author(s):  
Yasuo Harada
Keyword(s):  
Semicircular Canals

The Scanning Electron Microscopic Observation of the Vestibular Sensory Epithelia

1969 ◽  
Vol 27 ◽  
pp. 40-41
Author(s):  
D.J. Lim ◽  
W.C. Lane
Keyword(s):  
Semicircular Canals ◽  
Electron Microscopic Observation ◽  
Gravitational Acceleration ◽  
Electron Microscopic ◽  
Sensory Epithelia ◽  
Scanning Electron Microscopic ◽  
Vestibular Sensory Epithelia ◽  
And Function ◽  
Sand Piles ◽  
Active Investigation

The morphology and function of the vestibular sensory organs has been extensively studied during the last decade with the advent of electron microscopy and electrophysiology. The opening of the space age also accelerated active investigation in this area, since this organ is responsible for the sensation of balance and of linear, angular and gravitational acceleration.The vestibular sense organs are formed by the saccule, utricle and three ampullae of the semicircular canals. The maculae (sacculi and utriculi) have otolithic membranes on the top of the sensory epithelia. The otolithic membrane is formed by a layer of thick gelatin and sand-piles of calcium carbonate crystals (Fig.l).

The Use of Fluorescein for Identification and Preservation of the Facial Nerve and Semicircular Canals for Safe Mastoidectomy

Skull Base ◽  
2009 ◽  
Vol 19 (01) ◽  
Author(s):  
Cristian Gragnaniello ◽  
Mahmoud Kamel ◽  
Ossama Al-Mefty
Keyword(s):  
Facial Nerve ◽  
Semicircular Canals

Coordinate System of Three-Semicircular Canals.

2002 ◽  
Vol 61 (6) ◽  
pp. 391-402
Author(s):  
Yasuko Arai
Keyword(s):  
Coordinate System ◽  
Semicircular Canals

scholarly journals Gene therapy via canalostomy approach preserves auditory and vestibular functions in a mouse model of Jervell and Lange-Nielsen syndrome type 2

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xuewen Wu ◽  
Li Zhang ◽  
Yihui Li ◽  
Wenjuan Zhang ◽  
Jianjun Wang ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Mouse Model ◽  
Inner Ear ◽  
Viral Vectors ◽  
Survival Rates ◽  
Semicircular Canals ◽  
Dependent Manner ◽  
Syndrome Type ◽  
Dose Dependent

AbstractMutations in voltage-gated potassium channel KCNE1 cause Jervell and Lange-Nielsen syndrome type 2 (JLNS2), resulting in congenital deafness and vestibular dysfunction. We conducted gene therapy by injecting viral vectors using the canalostomy approach in Kcne1−/− mice to treat both the hearing and vestibular symptoms. Results showed early treatment prevented collapse of the Reissner’s membrane and vestibular wall, retained the normal size of the semicircular canals, and prevented the degeneration of inner ear cells. In a dose-dependent manner, the treatment preserved auditory (16 out of 20 mice) and vestibular (20/20) functions in mice treated with the high-dosage for at least five months. In the low-dosage group, a subgroup of mice (13/20) showed improvements only in the vestibular functions. Results supported that highly efficient transduction is one of the key factors for achieving the efficacy and maintaining the long-term therapeutic effect. Secondary outcomes of treatment included improved birth and litter survival rates. Our results demonstrated that gene therapy via the canalostomy approach, which has been considered to be one of the more feasible delivery methods for human inner ear gene therapy, preserved auditory and vestibular functions in a dose-dependent manner in a mouse model of JLNS2.

En bloc petrosectomy using a Gigli saw for petroclival lesions

1995 ◽  
Vol 83 (3) ◽  
pp. 559-560 ◽  
Author(s):  
Tomio Sasaki ◽  
Makoto Taniguchi ◽  
Ichiro Suzuki ◽  
Takaaki Kirino
Keyword(s):  
Facial Nerve ◽  
Semicircular Canals ◽  
Petrous Bone ◽  
New Technique ◽  
En Bloc ◽  
Content Type ◽  
A New Technique ◽  
Transtentorial Approach ◽  
Fine Print

✓ The authors report a new technique for en bloc petrosectomy using a Gigli saw as an alternative to drilling the petrous bone in the combined supra- and infratentorial approach or the transpetrosal—transtentorial approach. It is simple and easy and avoids postoperative cosmetic deformity. This technique has been performed in 11 petroclival lesions without injuring the semicircular canals, the cochlea, or the facial nerve.

scholarly journals Sensorimotor impairment from a new analog of spaceflight-altered neurovestibular cues

2020 ◽  
Vol 123 (1) ◽  
pp. 209-223
Author(s):  
Jordan B. Dixon ◽  
Torin K. Clark
Keyword(s):  
Head Tilt ◽  
Semicircular Canals ◽  
Control Groups ◽  
Head Restraint ◽  
The Subject ◽  
Sensorimotor Impairment ◽  
Self Motion ◽  
Future Work ◽  
Extended Exposure ◽  
Sensorimotor Performance

Exposure to microgravity during spaceflight causes central reinterpretations of orientation sensory cues in astronauts, leading to sensorimotor impairment upon return to Earth. Currently there is no ground-based analog for the neurovestibular system relevant to spaceflight. We propose such an analog, which we term the “wheelchair head-immobilization paradigm” (WHIP). Subjects lie on their side on a bed fixed to a modified electric wheelchair, with their head restrained by a custom facemask. WHIP prevents any head tilt relative to gravity, which normally produces coupled stimulation to the otoliths and semicircular canals, but does not occur in microgravity. Decoupled stimulation is produced through translation and rotation on the wheelchair by the subject using a joystick. Following 12 h of WHIP exposure, subjects systematically felt illusory sensations of self-motion when making head tilts and had significant decrements in balance and locomotion function using tasks similar to those assessed in astronauts postspaceflight. These effects were not observed in our control groups without head restraint, suggesting the altered neurovestibular stimulation patterns experienced in WHIP lead to relevant central reinterpretations. We conclude by discussing the findings in light of postspaceflight sensorimotor impairment, WHIP’s uses beyond a spaceflight analog, limitations, and future work. NEW & NOTEWORTHY We propose, implement, and demonstrate the feasibility of a new analog for spaceflight-altered neurovestibular stimulation. Following extended exposure to the analog, we found subjects reported illusory self-motion perception. Furthermore, they demonstrated decrements in balance and locomotion, using tasks similar to those used to assess astronaut sensorimotor performance postspaceflight.

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.

Inactivation of Semicircular Canals Causes Adaptive Increases in Otolith-Driven Tilt Responses

2002 ◽  
Vol 87 (3) ◽  
pp. 1635-1640 ◽  
Author(s):  
Dora E. Angelaki ◽  
Shawn D. Newlands ◽  
J. David Dickman
Keyword(s):  
Eye Movements ◽  
Semicircular Canal ◽  
Translational Motion ◽  
Semicircular Canals ◽  
Vertical Axis ◽  
Lateral Motion ◽  
Functional Interaction ◽  
Gaze Stabilization ◽  
Theoretical Evidence ◽  
Ocular System

Growing experimental and theoretical evidence suggests a functional synergy in the processing of otolith and semicircular canal signals for the generation of the vestibulo-ocular reflexes (VORs). In this study we have further tested this functional interaction by quantifying the adaptive changes in the otolith-ocular system during both rotational and translational movements after surgical inactivation of the semicircular canals. For 0.1–0.5 Hz (stimuli for which there is no recovery of responses from the plugged canals), pitch and roll VOR gains recovered during earth-horizontal (but not earth-vertical) axis rotations. Corresponding changes were also observed in eye movements elicited by translational motion (0.1–5 Hz). Specifically, torsional eye movements increased during lateral motion, whereas vertical eye movements increased during fore-aft motion. The findings indicate that otolith signals can be adapted according to a compromised strategy that leads to improved gaze stabilization during motion. Because canal-plugged animals permanently lose the ability to discriminate gravitoinertial accelerations, adapted animals can use the presence of gravity through otolith-driven tilt responses to assist gaze stabilization during earth-horizontal axis rotations.

Body Sensation of Low Frequency Noise of Ordinary Persons and Profoundly Deaf Persons

1983 ◽  
Vol 2 (3) ◽  
pp. 32-36 ◽  
Author(s):  
S. Yamada ◽  
M. Ikuji ◽  
S. Fujikata ◽  
T. Watanabe ◽  
T. Kosaka
Keyword(s):  
Low Frequency ◽  
Semicircular Canals ◽  
Normal Hearing ◽  
Frequency Noise ◽  
Low Frequency Noise ◽  
Body Sensation ◽  
Deaf Persons

Comparison of the thresholds of body sensation of profoundly deaf subjects and those of normal hearing, when exposed to intense low frequency noise, showed similar trends. Since the deaf subjects were judged to have normal balance mechanisms, it was concluded that the semicircular canals are not sensitive to low frequency noise at its normal levels in the environment.

Responses of vestibular units to stimulation of individual semicircular canals

1969 ◽  
Vol 24 (2) ◽  
pp. 310-324 ◽  
Author(s):  
Carlo Desole ◽  
Eugenio A. Pallestrini
Keyword(s):  
Semicircular Canals ◽  
Stimulation Of
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