CT结直肠重建对分析健康人排便机制的作用及其评价

目的 建立CT结直肠三维蕈建评估盆底结构和功能的方法学,并评估其可行性.方法 对19名健康志愿者(男8名,女11名,平均年龄42.8岁)行排粪造影和CT结直肠重建两项检查,分别在两项检查所得影像上对肛直角等参数进行测量.结果 在健康人中,CT重建技术测得的肛直角(例如ARA-a)均值静息时为(101±13)°,提肛时(83±12)°,力排时(124±13)°;肛上距均值静息时为(10±6)mm,提肛时(中位数)为-2(-8～3)mm,力排时(27 ±11)mm;肛管长度均值静息时为(29±7)mm,提肛时(39 ±8)mm,力排时(22 ±5)mm.上述参数在提肛或力排时的变化趋势与排粪造影相同(均P>0.05).静息、提肛或力排时测得的肛直角、肛管长度,在排粪造影和CT重建两种方法上差异均无统计学意义(均P>0.05);CT重建测得的静息、提肛或力排时的肛上距显著小于排粪造影测得的相应数值[(31 ±11)mm、18(-1～26)mm、(50 ±12)mm,均P<0.01].排粪造影和CT重建两种方法在反映同一受试者力排时肛直角变化(r=0.315、0.361,均P>0.05)或盆底下降程度上(r=0.420,P>0.05)的相关性和一致性较差.结论 CT结直肠重建可帮助评估排便功能与结构.

Value of computed tomographic colonography in analyzing mechanism of defecation in healthy subjects

Objective To establish the methodology of 3-dimensional CT reconstruction of colon and rectum in evaluating anorectum and pelvic floor function.Methods 19 healthy volunteers,8 males and 11 females,aged 42.8,received both defeeography and 3-dimensional CT reconstruction of colon and reetum.Relevant parameters were compared between the two methods. Results (1)CT reconstruction shewed that the average vahe of anorectal angle(ARA)was(101±13)°when resting,(83±12)°when squeezing,and(124±13)°when defecating;the average values of the distance between the upper part of anal canal and the pubocoecygeal line(DUAC)was(10±6)mm when resting,-2(-8-3)mm when squeezing,and(27±11)mm when defecating;and the average value of the anal canal length(ACL)was (29 ±7)mm when resting,(39±8)nlin when squeezing,and(22 ±5)mm when defecating.The change trends of ARA,DUAC,and ACL during squeezing and defecating in CT reconstruction were the same as those in defecography.(2)No significant differences were found in ARA and ACL meagured by the two methods;but the DUAC values measured by defeeography when resting,squeezing,and defecating were (31 ±11)mm,18(-1-26)mm,and(50±12)mm respectively,all significandy longer those measured bv CT reconstruction(all P<0.01).(3)During defecation,the value changes of ARA was not Bignificantly correlated between these 2 methods(r=0.315,0.361,beth P>0.05).Conclusion 3-dimensional CT reeonstmction of colon and rectum is helpful in evaluation of anoreetum and pelvic floor function.