Feasibility of presupposed reference line based on MRI as ultrasound reference line in pelvic organ prolapsed / 中国医学影像技术

ABSTRACT

Objective To provide valuable references for ultrasonic diagnosis of pelvic organ prolapsed (POP) by finding an eas ily detecting referential line based on MRI.Methods Data of 107 patients who underwent pelvic MRI were retrospectively analyzed.All the patients were divided into 6 groups according to ageGroup 1 (20 29 years old),group 2 (30-39 years old),group 3 (40-49 years old),group 4 (50-59 years old),group 5 (60-69 years old) and group 6 (≥70 years old group).Four reference lines were set basing on the median sagittal view of T2WIPS-PS line (the line connecting the two endpoint of the pubic symphysis),PIAS line (the line connecting the inferior margin of pubic symphysis and the bottom of sphincter internal anal sphincter),PPC line (the line connecting of the inferior margin of pubic symphysis and the point of the pubococcygeous attached on the rectum) and PM line (the line connecting of the inferior margin of pubic symphysis and the M point [the midpoint of the line from the crosspoint of PPC line and the front wall of the rectum mucosa to the bottom of sphincter internal anal sphincter]).The angles between the horizontal line and PS-PS line,PIAS line,PM line,PPC line (angle 1,angle 2,angle 3,angle 4) were measured,respectively.The differences of the angle among various age-groups were compared.The consistency between the two observes were evaluated.Results PM line was the closest line to the horizontal line.There was no statistical differences of angle 1,angle 2 and angle 3 among the 6 groups (all P＞0.05).The difference of angle 4 among the 6 groups were significant (F=3.42,P=0.01).Intergroup pairwise comparisons showed that significant differences were found between group 1 and group 4,group 5,group 6,between group 2 and group 4,group 5,group 6,between group 3 and group 4,group 5,group 6,respectively (all P＜0.05).And no significant difference was found in the other comparisons.The consistency of the two observers in meaning angle 1,angle 3 and angle 4 were good,but the consistency of angle 2 was poor.Conclusion Of all the referential lines,PM is the closest to the horizontal line and is less influenced by the patient's age.However,the feasibility of using PM lines as the ultrasound referential line is still unclear.