scholarly journals Vertical Semicircular Canal-Stimulative Post-Rotatory Nystagmus: Comparison of the Nystagmus Induced by Lateral Semicircular Canal-Stimulation in Normal Adult Subjects.

1996 ◽  
Vol 55 (4) ◽  
pp. 380-386 ◽  
Author(s):  
Masahiro Morita ◽  
Noriaki Takeda ◽  
Izumi Koizuka ◽  
Takeshi Kubo
Keyword(s):  
Semicircular Canal ◽  
Normal Adult ◽  
Lateral Semicircular Canal ◽  
Vertical Semicircular Canal

A head-tilt caloric test for evaluating the vertical semicircular canal function

2009 ◽  
Vol 129 (11) ◽  
pp. 1226-1231 ◽  
Author(s):  
Sachiko Aoki ◽  
Yasuko Arai ◽  
Keiko Yoda ◽  
Suguru Nishida
Keyword(s):  
Semicircular Canal ◽  
Head Tilt ◽  
Caloric Test ◽  
Vertical Semicircular Canal

The functional allometry of semicircular canals, fins, and body dimensions in the juvenile centrarchid fish, Lepomis gibbosus (L.)

Development ◽  
1973 ◽  
Vol 29 (3) ◽  
pp. 721-743
Author(s):  
Howard C. Howland ◽  
Joseph Masci
Keyword(s):  
Body Mass ◽  
Semicircular Canal ◽  
Semicircular Canals ◽  
Lepomis Gibbosus ◽  
Swimming Velocity ◽  
Body Dimensions ◽  
Moments Of Inertia ◽  
Significant Difference ◽  
Vertical Semicircular Canal ◽  
Vertical Semicircular Canals

1. The ontogenetic allometry of radii of curvature and the tube radii of the semicircular canals of approximately 85 juvenile (2–20 g) centrarchids of the species Lepomis gibbosus (L.) was investigated. The radii of curvature of the semicircular canals have different allometries; these arefor the anterior vertical, posterior vertical and horizontal canals respectively. The differences in growth exponents between the anterior and posterior vertical semicircular canals and between the anterior vertical and horizontal semicircular canals were statistically significant (P < 0·02 and P < 0·05 respectively). 2. Body mass and standard length were almost equally good predictors of the radii of curvature of the anterior vertical semicircular canals, but body mass was the better predictor of the radii of curvature of the posterior vertical and horizontal semicircular canals, as judged by the magnitude of the mean squares about the logarithmic regressions of radii on length and mass. 3. By measuring and estimating the area moments of the fins of the fish, the moments of inertia about various axes and the allometry of the characteristic swimming velocity of the fish, we attempted to account for the magnitude and direction of the differences in allometric growth exponents of the radii of curvature of the semicircular canals. Unexplained by our best estimate of growth exponents was the very high value observed for the posterior vertical semicircular canals. 4. No significant correlation could be found between the residuals of the major dimensions of the posterior vertical semicircular canals and those of body width or depth once the influence of body mass was removed. This finding suggests the rejection of the hypothesis that the allometry of this semicircular canal is simply correlated with overall body expansion in its plane. 5. The discrepancies between our predictions and observations of growth exponents could be explained by a gradual increase of the spring constant of the semicircular canals on the order ofthough they may also be due to other factors neglected in our model, e.g. the allometry of the added mass of the fish. 6. No evidence suggested that the shape of the semicircular canals was altered over the size range of the fish we studied. However, among the fins of the fish and the major body dimensions, only the width and the depth of the fish exhibited growth constants that did not differ significantly from each other. 7. We computed the effective toroidal radii of the non-toroidal-shaped vertical semicircular canals and found that the equivalent toroidal radius of the anterior vertical semicircular canal was consistently greater than that of the posterior vertical semicircular canal. This difference is explicable on the basis of the different moments of inertia of the animal about axes through the center of gravity and parallel to the axes of the semicircular canals. 8. We computed the allometry of the ratios R̄/r2 for all three semicircular canals and found in accordance with the prediction of Jones & Spells that they did not differ significantly from zero. 9. The allometry of the outer tube radii of the several semicircular canals was determined, and, while there was no significant difference in the growth exponents of the tube radii, it was noted that the tube radius of the horizontal semicircular canal was consistently and significantly smaller than that of the vertical semicircular canal. We suggested that this difference might be due to the broader range of frequencies that the fish experienced about its yaw axis. 10. Taken as a whole the data and calculations of this paper generally support the theory that the dimensions of the semicircular canals and the ontogenetic changes in them attune the semicircular canals to the angular frequency spectra that the fish experience about their axes.

scholarly journals Comparative Study of Preoperative Radiological Findings with Intraoperative Surgical Findings in Squamosal Type of Chronic Otitis Media

2021 ◽  
Vol 10 (25) ◽  
pp. 1862-1865
Author(s):  
Sanjana Pradeep ◽  
Swaroop Dev ◽  
Jyothi Swarup Raju ◽  
Shravya Pasunuti
Keyword(s):  
Temporal Bone ◽  
Otitis Media ◽  
Semicircular Canal ◽  
Chronic Otitis Media ◽  
Sigmoid Sinus ◽  
Lateral Semicircular Canal ◽  
High Resolution Computed Tomography ◽  
Tissue Mass ◽  
Hrct Temporal Bone ◽  
A Prospective Study

BACKGROUND Chronic otitis media (COM) of squamosal type is associated with cholestatoma with potential complications. Clinical examination and high resolution computed tomography (HRCT) scans are necessary to assess the disease site and extension. The purpose of the study was to compare the preoperative HRCT findings with the intraoperative surgical findings in squamosal type of chronic otitis media as well as various parameters in HRCT temporal bone and intraoperative findings. METHODS A prospective study was conducted on 30 patients aged between 18 and 60 years of both the genders who presented with chronic otitis media squamosal type, for a period of 22 months who attended the outpatient department of ENT. RESULTS HRCT findings and intraoperative findings were compared and results were analysed. Facial canal erosion (P - 0.0031), tegmen plate erosion (P - 0.0001), sigmoid sinus plate erosion (P - 0.002) were found to be statistically significant. Lateral semicircular canal fistula (P - 0.36) and ossicular status malleus (P - 1.000), incus (P - 0.949), stapes suprastructure (P - 0.984), and stapes footplate erosion (P - 0.977) were found to be statistically insignificant. CONCLUSIONS In our study, HRCT imaging for COM squamosal type, accurately depicted the soft tissue mass, erosion of tegmen plate, sigmoid sinus plate, scutum, lateral semicircular canal fistula, incus and suprastructure of stapes erosion and the same were found intraoperatively as well. Our study showed good comparison between the preoperative HRCT scans and the surgical findings in cholesteatoma cases. HRCT is confirmed to be valuable in the diagnosis and in guiding the surgical management of cholesteatoma. KEY WORDS Chronic Otitis Media, Cholesteatoma, HRCT Temporal Bone, Modified Radical Mastoidectomy

scholarly journals A test of the lateral semicircular canal correlation to head posture, diet and other biological traits in “ungulate” mammals

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
J. Benoit ◽  
L. J. Legendre ◽  
A. A. Farke ◽  
J. M. Neenan ◽  
B. Mennecart ◽  
...  
Keyword(s):  
Semicircular Canal ◽  
Ct Scanning ◽  
Biological Traits ◽  
Large Sample Size ◽  
Strongly Correlated ◽  
Lateral Semicircular Canal ◽  
Extinct Species ◽  
Head Posture ◽  
Bony Labyrinth ◽  
Phylogenetic Regression

Abstract For over a century, researchers have assumed that the plane of the lateral semicircular canal of the inner ear lies parallel to the horizon when the head is at rest, and used this assumption to reconstruct head posture in extinct species. Although this hypothesis has been repeatedly questioned, it has never been tested on a large sample size and at a broad taxonomic scale in mammals. This study presents a comprehensive test of this hypothesis in over one hundred “ungulate” species. Using CT scanning and manual segmentation, the orientation of the skull was reconstructed as if the lateral semicircular canal of the bony labyrinth was aligned horizontally. This reconstructed cranial orientation was statistically compared to the actual head posture of the corresponding species using a dataset of 10,000 photographs and phylogenetic regression analysis. A statistically significant correlation between the reconstructed cranial orientation and head posture is found, although the plane of the lateral semicircular canal departs significantly from horizontal. We thus caution against the use of the lateral semicircular canal as a proxy to infer precisely the horizontal plane on dry skulls and in extinct species. Diet (browsing or grazing) and head-butting behaviour are significantly correlated to the orientation of the lateral semicircular canal, but not to the actual head posture. Head posture and the orientation of the lateral semicircular canal are both strongly correlated with phylogenetic history.

scholarly journals Isolated lateral semicircular canal aplasia: Functional consequences

2016 ◽  
Vol 133 (3) ◽  
pp. 199-201 ◽  
Author(s):  
G. Michel ◽  
F. Espitalier ◽  
A.-S. Delemazure ◽  
P. Bordure
Keyword(s):  
Semicircular Canal ◽  
Lateral Semicircular Canal ◽  
Functional Consequences

A head-tilt caloric test for evaluating the vertical semicircular canal function

2009 ◽  
pp. 1-6
Author(s):  
Sachiko Aoki ◽  
Yasuko Arai ◽  
Keiko Yoda ◽  
Suguru Nishida
Keyword(s):  
Semicircular Canal ◽  
Head Tilt ◽  
Caloric Test ◽  
Vertical Semicircular Canal
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