UNASSIGNED: Using high-resolution MRI scans of 55 normal inner ears, 3D models of the semicircular canals were segmented. These were complemented by detailed membrane labyrinth models from micro-CT scans of human temporal bones, accessed via the Comparative Ear Bank (www.earbank.org). A statistical shape model of inner ears and eyeballs was established, and a standardized 3D spatial coordinate system was created. The horizontal plane was defined using the top of the common crus and the bottom of the eyeballs. This calibrated reference system allowed for precise quantification of crista ampullaris orientations by calculating angles between the defined crista planes and coordinate planes.
UNASSIGNED: The plane of the ampulla and the corresponding semicircular canal plane are nearly perpendicular to each other. In the upright position, the posterior semicircular canal crista ampullaris formed an angle of 48.9° with the horizontal plane. The relative orientations of the crista ampullaris of the lateral and superior canals were also defined. Furthermore, we identified \"zero-point planes\" representing crista orientations perpendicular to gravity, which resulted in minimal ampullary stimulation. A 6.2° tilt to the left in the supine position resulted in the plane of the left lateral semicircular canal crista ampullaris being parallel to the direction of gravity.
UNASSIGNED: This study elucidates the precise spatial orientation of the crista ampullaris, thereby providing an anatomical basis for understanding BPPV pathophysiology and improving the accuracy of diagnostic and therapeutic maneuvers. The findings have the potential to significantly enhance the management of BPPV and other inner ear disorders.
■使用55只正常内耳的高分辨率MRI扫描,对半规管的3D模型进行了分割。这些由来自人类颞骨的显微CT扫描的详细的膜迷宫模型补充,通过比较耳朵银行访问(www.earbank.org)。建立了内耳和眼球的统计形状模型,并创建了标准化的3D空间坐标系。使用共同小腿的顶部和眼球的底部来定义水平面。此校准的参考系统允许通过计算定义的crista平面和坐标平面之间的角度来精确量化crista壶腹方向。
■壶腹平面和相应的半规管平面几乎彼此垂直。在直立位置,后半规管crista壶腹与水平面成48.9°的角度。还定义了外侧和上运河的crista壶腹的相对方向。此外,我们确定了代表垂直于重力的crista方向的“零点平面”,这导致了最小的壶腹刺激。仰卧位向左倾斜6.2°,导致左侧半规管crista壶腹的平面平行于重力方向。
■这项研究阐明了crista壶腹的精确空间方向,从而为理解BPPV病理生理学和提高诊断和治疗操作的准确性提供解剖学基础。这些发现有可能显着增强BPPV和其他内耳疾病的管理。