Dix-Hallpike 검사에 대한 수학적 고찰 = A Mathematical Consideration on the Dix-Hallpike maneuver

다국어 초록 (Multilingual Abstract)

Background and Objectives: At the beginning of the Dix-Hallpike maneuver, one of the two functional pair
planes of the vertical canals is presumed to lie in the sagittal plane. However, this presumption is not correct.
This paper aims to describe this problem more clearly and speculate on clinical implications. Mathematical and
theoretical reasoning will be discussed.
Materials and Methods: Two sets, each composed of three perpendicular planes, were modeled for simplified
semicircular canals in the anatomical position with a 3D modeler. After a yaw rotation of 45°, the surface normal
of the vertical canal plane is compared with that of the true sagittal plane.
Results: The angle between the two normals was approximately 21.1 degrees. The theoretical vertical canal
plane did not lie in the sagittal plane at the beginning position of Dix-Hallpike maneuver.
Conclusions: More exact Dix-Hallpike maneuvers may require a roll tilting about 20° toward the affected side.

다국어 초록 (Multilingual Abstract)

Background and Objectives: At the beginning of the Dix-Hallpike maneuver, one of the two functional pair
planes of the vertical canals is presumed to lie in the sagittal plane. However, this presumption is not correct.
This paper aims to describe this problem more clearly and speculate on clinical implications. Mathematical and
theoretical reasoning will be discussed.
Materials and Methods: Two sets, each composed of three perpendicular planes, were modeled for simplified
semicircular canals in the anatomical position with a 3D modeler. After a yaw rotation of 45°, the surface normal
of the vertical canal plane is compared with that of the true sagittal plane.
Results: The angle between the two normals was approximately 21.1 degrees. The theoretical vertical canal
plane did not lie in the sagittal plane at the beginning position of Dix-Hallpike maneuver.
Conclusions: More exact Dix-Hallpike maneuvers may require a roll tilting about 20° toward the affected side.

참고문헌 (Reference)

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