The Study Of The Method For Abtaining The Location Of Baliao With Assistance Of CT Three-dimensionanal Reconstruction

Background:BaLiao is the abbreviation of ShangLiao(BL31),CiLiao (BL32),ZhongLiao (BL33),XiaLiao (BL34). There are four acupoints on either side of the sacral vertebrae. We call them BaLiao which belong to the Bladder Meridian of Foot-Taiyang.BaLiao have a wide range of therapeutic effects in clinical practice.The disease of colon and rectum,urinary system,movement system and genital system can be treated with the acupuncture of BaLiao. But the location of BaLiao is difficult to fixed since ancient times which makes BaLiao the uncommonly-used acupoints in clinical practice.The WHO Standard of Acupuncture Points Location defines that BaLiao are at the 4 paires wholes on posterior sacral foramen.This study aims at finding a simple and convenient way to fix the location of BaLiao through observing and measuring relevant indexes by CT three-dimensional reconstruction of pelvic cavity.Objective:Firstly we reconstruct sacrum by CT three-dimensional techonique.Then accurate measure and analysis of relevant indexes are required to obtain an generalized universality to help find the convenient and suitable measures for clinically fixing BaLiao.Methods:Image datas are collected from patients who receive abdominal CT scan including pelvic cavity at NanJing Chinese Hospital Medical Image Department between May and December 2014.These images are reconstructed to three-dimension pelvic cavity model at FOV 320mm*320mm, matrix 512*512 and slice 0.6mm.Then they are transferred to workstation which could deal with the model in Inspace 3D platform.Interference in this model should be removed like soft tissue,vessel and anything redundant. Contrast ratio, diaphaneity and luminance need to be adjusted to show the pelvic cavity perfectly.The needed data should be measured precisely in specific size and angle.Based on gender group,data acquired from measuring are analysized statistically.Results:1 The distance between Sacral cornu and ShangLiao,CiLiao,ZhongLiao and XiaLiao on the same side respectively is 68.9 ± 9.21mm,49.7 ± 6.14mm,29.8 ± 4.08mm and 14.2 ± 7.11mm for male; 64.4 ± 8.64mm, 47.2 ± 5.64mm,28.7 ± 4.39mm and 13.5 ± 8.17mm for female; the transverse distance between BaLiao respectively 39.2 ± 4.19mm,33.4 ± 3.58mm,28.8 ± 3.24mm and 28.0 ± 3.45mm for male; 38.1±3.97mm,32.9±3.75mm,27.7±3.36mm and 27.0±2.45mm for female. According to the distance between the sacral cornu and the posterior sacral foramen,posterior sacral foramen can be determined in a vertical orientation on the sacrum. According to half of the transverse distance between holes at same horizontal line, posterior sacral foramen can be determined in a transverse orientation on the sacrum.2 Transverse diameter and vertical diameter of posterior sacral foramen help determine the size of BaLiao.3 The indexes of CiLiao have s strong correlation with each other. The distance between posterior sacral foramen and sacral cornu (x) has a linear correlation with the distance between posterior sacral foramen and posterior superior iliac spine (y).The regression equation:male:left y=-0.24x+4.28,right y=-0.24x+4.25;female:left y=-0.24x+4.15,right y=-0.24x+4.06.According to the equation,the measured location can be amended.4 The vertical orientation distance between posterior sacral foramens can help locate the definite location of ShangLiao,ZhongLiao and XiaLiao.Conclusion:1 The easy way of locating BaLiao and amending them will provide clinical reference.2 Three-dimensional CT reconstruction provides method which is convenient, accurate and practical for measuring revelent indexes of BaLiao.