Abstract：Objective To investigate the clinical application of diffusion tensor imaging (DTI) and fibre tractography in evaluating the levator ani muscle injury after first vaginal delivery. It can provide objective evidence for clinical rehabilitation treatment after delivery and prevention of pelvic organ prolapse.Methods From June 2014 to January 2015, 50 primiparous six months after vaginal delivery and 33 normal women without experience of pregnancy and delivery as control group were prospectively studied in Tianjin First Center Hospital. All women underwent axial, coronal fast spin-echo T2-weighted imaging(FSE T2WI)sequences and DTI sequences of the pelvic floor. Offline fibre tractography of each major levator ani subdivision (pubovisceralis and iliococcygeus) and quality assessment of fibre tracking were performed. From accurate tracking results fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated. FSE-T2WI were evaluated for levator ani muscle abnormalities. And on the basis of the levator ani muscle defects, the primiparous were divided into two groups. The pubovisceralis normal group and pubovisceralis injured group, iliococcygeus normal group and iliococcygeus injured group respectively. FA, ADC values between the control group,levator ani muscle normal group and injured group were compared using ANOVA.Results The quality of the 3D representation was judged as accurate for all of the pubovisceralis and inaccurate for all of the iliococcygeus. Twelve (24.0%,12/50) primiparous had injuries in their pubovisceralis, 9 primiparous had unilateral defects and three had bilateral amyotrophy. Four (8.0%, 4/50) primiparous had injuries in their iliococcygeus, all of them showed unilateral defects. No levator ani defects were identified in nulliparous women. The FA values of pubovisceralis among control group, pubovisceralis normal group and pubovisceralis injured group were 0.49±0.08, 0.52±0.11, and 0.53±0.13, respectively. The ADC values were (1.79±0.29)×10-3 mm2/s, (1.75±0.34)×10-3 mm2/s, and (1.93±0.35)×10-3 mm2/s. There was no statistical significance (F=1.217, 1.747 respectively, all P values>0.05).Conclusions DTI with fibre tractography provides a satisfactory 3D representation of pubovisceralis. The study of iliococcygeus is more difficult. DTI and fiber tractography cannot provide accurate quantified diagnostic evidence to differentiate normal and abnormal states of the levator ani muscle.
崔璨,李娜,程悦,赵玉娇,吴彦洪,尹建忠,沈文. MR扩散张量成像和纤维束示踪技术评价经阴道分娩初产妇肛提肌损伤[J]. 中华解剖与临床杂志, 2016, 21(4): 306-310.
Cui Can, Li Na, Cheng Yue, Zhao Yujiao, Wu Yanhong, Yin Jianzhong, Shen Wen. Evaluation of the injury of levator ani muscle in primipara after vaginal delivery using diffusion tensor imaging and fibre tractography. Chinese Journal of Anatomy and Clinics, 2016, 21(4): 306-310.
Corton MM. Anatomy of pelvic floor dysfunction[J]. Obstet Gynecol Clin North Am, 2009, 36(3): 401-419. DOI:10.1016/j.ogc.2009.09.002
[2]
Rostaminia G, White D, Hegde A, et al. Levator ani deficiency and pelvic organ prolapse severity[J]. Obstet Gynecol, 2013, 121(5): 1017-1024
[2]
Rostaminia G, White D, Hegde A, et al. Levator ani deficiency and pelvic organ prolapse severity[J]. Obstet Gynecol, 2013, 121(5): 1017-1024. DOI:10.1097/AOG.0b013e31828ce97d
[3]
Berger MB, Morgan DM, DeLancey JO. Levator ani defect scores and pelvic organ prolapse: is there a threshold effect[J]. Int Urogynecol J, 2014, 25(10): 1375-1379. DOI:10.1007/s00192-014-2388-8
[4]
DeLancey JO, Morgan DM, Fenner DE, et al. Comparison of levator ani muscle defects and function in women with and without pelvic organ prolapse[J]. Obstet Gynecol, 2007, 109(2 Pt 1): 295-302. DOI:10.1097/01.AOG.0000250901.57095.ba
[5]
Li R, Song Y, Ma M. Relationship between levator ani and bony pelvis morphology and clinical grade of prolapse in women[J]. Clin Anat, 2015, 28(6): 813-819. DOI:10.1002/ca.22536
[6]
Chan SS, Cheung RY, Yiu AK, et al. Prevalence of levator ani muscle injury in Chinese women after first delivery[J]. Ultrasound Obstet Gynecol, 2012, 39(6): 704-709. DOI:10.1002/uog.10132
[7]
Miller JM, Low LK, Zielinski R, et al. Evaluating maternal recovery from labor and delivery: bone and levator ani injuries[J]. Am J Obstet Gynecol, 2015, 213(2): 188.e1-181.e11. DOI:10.1016/j.ajog.2015.05.001
[8]
van Delft K, Thakar R, Sultan AH, et al. Levator ani muscle avulsion during childbirth: a risk prediction model[J]. BJOG, 2014, 121(9): 1155-1163. DOI:10.1111/1471-0528.12676
[9]
Rousset P, Delmas V, Buy JN, et al. In vivo visualization of the levator ani muscle subdivisions using MR fiber tractography with diffusion tensor imaging[J]. J Anat, 2012, 221(3): 221-228. DOI:10.1111/j.1469-7580.2012.01538.x
Kearney R, Sawhney R, DeLancey JO. Levator ani muscle anatomy evaluated by origin-insertion pairs[J]. Obstet Gynecol, 2004, 104(1): 168-173. DOI:10.1097/01.AOG.0000128906.61529.6b
[12]
Singh K, Reid WM, Berger LA. Magnetic resonance imaging of normal levator ani anatomy and function[J]. Obstet Gynecol, 2002, 99(3): 433-438. DOI: 10.1016/S0029-7844(01)01743-4
Zijta FM, Froeling M, van der Paardt MP, et al. Feasibility of diffusion tensor imaging (DTI) with fibre tractography of the normal female pelvic floor[J]. Eur Radiol, 2011, 21(6): 1243-1249. DOI:10.1007/s00330-010-2044-8
[15]
Zaraiskaya T, Kumbhare D, Noseworthy MD. Diffusion tensor imaging in evaluation of human skeletal muscle injury[J]. J Magn Reson Imaging, 2006, 24(2): 402-408. DOI:10.1002/jmri.20651
2016, Vol. 21 
