DSA study on evaluation of the aspiration prevention posture in dysphagic patients

本研究旨在探讨吞咽困难患者的测量参考线，特别是体位改变技术的应用。视频荧光摄影是最常用的检查吞咽困难的病人。该设备的两个主要部件是X射线管和图像增强器（I.I.）。自从I.I.具有本质上称为线轴失真的失真，I.I.扭曲是必要的。我们开发了I.I.应用该程序对74例对照组、150例患者组和40例患者组进行了研究。使用这些视频荧光图像，我们检查了参考线。腭平面作为水平指标在喉延长患者组中42%不能确定。若以鼻底平面代替腭平面，则水平指数不能确定的病例减少到29%。将颈椎线确定为垂直线，虽然几乎所有的病例都能看到第4颈椎<th>，但约有10%的病例由于第5颈椎位于照射野之外而看不到，利用这些水平和垂直指标，我们研究了吞咽姿势改变的影响。下颌向下拉前、后角度变化平均13 °。舌面与咽面距离的T_2-P_2和T_3-P_3比值从Ment on的0.82增加到0.86，从Ment on的0.76增加到0.81。这意味着拉下下巴会使咽部变窄。在确定颈椎连线时，以C2和C4下端连线可能优于C2和C5。2.鼻腔可以用来代替腭平面。

The purpose of this study was to determine the reference lines for measurement of dyphagic patients, especially the usage of posture change technique. Videofluorography is most popular examination for dysphagic patients. The two main components of the equipment is X-ray tube and Image Intensifier (I.I.). Since the I.I. has distortion essentially called spool distortion, the correction of the I.I. distortion is necessary. We developed the program for distortion compensation of I.I. which corrected the distortion satisfactory.Using this program we studied Control group (74 cases), Patient group (150 cases), and Chin tack application patient group (40 cases). Using these videofluorographic images, we examined reference lines. The palatal plane as a horizontal index was not able to determine 42 % in patient group when their larynx have elongated. If we used nasal floor instead of the palatal plane, the cases cannot determine the horizontal index were reduced to 29 %. Determining the cervical vertebral line as a vertical, although, almost all the cases of the 4^<th> vertebra could be seen although the 5th cervical vertebra was not seen about 10 % because it located in outside the exposure field.Using these horizontal and vertical indices, we studied the effect of swallowing posture change. The angle change before and after pulling down the jaw was measured mean 13 degrees. Comparing the habitual position and the chin tuck position, T2-P2 and T3-P3 distance ratio between the tongue surface and the surface of the pharynx from Ment on increased from 0.82 to 0.86 and 0.76 to 0.81.respectively. That means pulling down the chin makes the width of the pharynx narrow.In conclusion, this study suggests 1. when determining the cervical vertebral line to connect the lower ends of C2 and C4 may be better than C2 and C5. 2.nasal cavity may be used instead of palatal plane.