Evaluation of isolated urinary stress incontinence 2 according to the type of lesion on the levator ani muscle 3 using 3-4d transperineal ultrasound 36 months post-partum

International Urogynecology Journal EVALUATION OF ISOLATED URINARY STRESS INCONTINENCE ACCORDING TO THE TYPE OF LESION ON THE LEVATOR ANI MUSCLE USING 3-4D TRANSPERINEAL ULTRASOUND 36 MONTHS POST-PARTUM. --Manuscript Draft-- Manuscript Number: IUJO-D-16-00459R2 Full Title: EVALUATION OF ISOLATED URINARY STRESS INCONTINENCE ACCORDING TO THE TYPE OF LESION ON THE LEVATOR ANI MUSCLE USING 3-4D TRANSPERINEAL ULTRASOUND 36 MONTHS POST-PARTUM. Article Type: Original Article Corresponding Author: José Antonio García Mejido, Gynecologist Hospital Universitario de Valme Sevilla, Sevilla SPAIN Corresponding Author Secondary Information: Corresponding Author's Institution: Hospital Universitario de Valme Corresponding Author's Secondary Institution: First Author: José Antonio García Mejido, Gynecologist First Author Secondary Information: Order of Authors: José Antonio García Mejido, Gynecologist Pamela Valdivieso Mejias, Gynecologist Ana Fernández Palacin, Proffesor María José Bonomi Barby, Gynecologist Paloma De la Fuente Vaquero, Gynecologist José Antonio Sainz Bueno, Gynecologist Order of Authors Secondary Information: Funding Information: Abstract: Abstract: INTRODUCTION Vaginal delivery can lead to pelvic floor disorders. Many authors have described pelvic floor injuries which can predict future defects such as urinary incontinence and pelvic organ prolapse. We propose the assessment of urinary stress incontinence and its association with levator ani muscle(LAM) microtrauma(>20% in the levator hiatus area during Valsalva) and macrotraumas (avulsion) identified by 3/4D transperineal ultrasound(3D-TpUS) 36months post-partum. MATERIALS AND METHOD Prospective observational study including 168 nulliparous women. All patients included were nulliparous with singleton gestation in cephalic presentation, at≥37 weeks and were recruited on the first day after delivery. 36 months after delivery,3D-TpUS was carried out to identify LAM lesions (macro or micro). Clinical assessment of urinary stress incontinence (USI) was based on the ICIQ-UI-SF-test; a simple-stress-test and urodynamic-test were carried out in the same visit. RESULTS A total of 105nulliparous women were studied (51 spontaneous deliveries(SpD) and 54vacuum assisted deliveries (VD)). Microtraumas were identified in 35.3%of SpD and 20.4%of VD. Macrotraumas (avulsion) were identified in 9.8%of SpD and 35.2%of Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation VD(p=0.006). No differences were found in USI between study groups or in relation to the identification of LAM defects (19.2% in the no lesion group, 25%in macrotrauma and 13.8% in microtrauma; P=not significant). Neither were significant differences found in the results from the different study groups in the ICIQ-UI-SF test(12.7±2.2 no lesion group, 12.5±4.2 in macrotrauma and 13.25±4.8 in microtrauma;p=NS). CONCLUSION No difference was observed in USI between patients with and without LAM lesions(microtrauma or macrotrauma) 36months post delivery. Response to Reviewers: Like 'see attachment' Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation 1 EVALUATION OF ISOLATED URINARY STRESS INCONTINENCE 1 ACCORDING TO THE TYPE OF LESION ON THE LEVATOR ANI MUSCLE 2 USING 3-4D TRANSPERINEAL ULTRASOUND 36 MONTHS POST-PARTUM. 3 4 Autors 5 6 García Mejido, José Antonio 1 (Autor de correspondencia) 7 Valdivieso Mejias, Pamela 2 8 Fernández Palacín, Ana 3 9 Bonomi Barby, María José 1 10 De la Fuente Vaquero, Paloma 1 11 Sainz Bueno, José Antonio 1,3 (Autor de correspondencia) 12 13 14 1 Hospital Universitario de Valme, Obstetrica y Ginecología. Sevilla, ES 15 2 Hospital Ginemed, Obstetricia y Ginecología Sevilla, ES 16 3 Universidad de Sevilla, Sevilla, Andalucía, ES 17 18 19 20 Corresponding Authors: 21 García Mejido, José Antonio y Sainz Bueno, José Antonio 22 Hospital Universitario Virgen de Valme (Sevilla) CP:41014. España 23 e-mail: 24 [email protected] and [email protected] 25 Manuscript clean Click here to download Manuscript Manuscript clean.doc Click here to view linked References 2 Teléfono: 955015385 26 27 28 Autorship: Each author must qualify by having participated actively and sufficiently in 29 the study that is being performed and reported. 30 31 32 Conflict of interest: It doesn't exist any trade association of any author of the text 33 neither any economic benefit with the realization of this work and their publication 34 35 Each author's contribution: 36 García Mejido, José Antonio writing/conducting the study Valdivieso Mejias, Pamela writing/conducting the study Fernéndez Palacín, Ana writing/conducting the study Bonomi Barby, María José writing/conducting the study De la Fuente Vaquero, Paloma writing/conducting the study Sainz Bueno, José Antonio writing/conducting the study 37 38 Words summary:268 39 Words of the manuscript: 2362 40 Clinical trial registration: 31 41 42 3 43 EVALUATION OF ISOLATED URINARY STRESS INCONTINENCE 44 ACCORDING TO THE TYPE OF LESION ON THE LEVATOR ANI MUSCLE 45 USING 3-4D TRANSPERINEAL ULTRASOUND 36 MONTHS POST-PARTUM. 46 47 Abstract: 48 49 INTRODUCTION 50 51 Vaginal delivery can lead to pelvic floor disorders. Many authors have described pelvic 52 floor injuries which can predict future defects such as urinary incontinence and pelvic 53 organ prolapse. We propose the assessment of urinary stress incontinence and its 54 association with levator ani muscle (LAM) microtrauma (>20% in the levator hiatus 55 area during Valsalva) and macrotraumas (avulsion) identified by 3/4D transperineal 56 ultrasound (3D-TpUS) 36 months post-partum. 57 58 MATERIALS AND METHOD 59 60 Prospective observational study including 168 nulliparous women. All patients included 61 were nulliparous with singleton gestation in cephalic presentation, at ≥37 weeks and 62 were recruited on the first day after delivery. 36 months after delivery, 3D-TpUS was 63 carried out to identify LAM lesions (macro or micro). Clinical assessment of urinary 64 stress incontinence (USI) was based on the ICIQ-UI-SF test; a simple stress test and 65 urodynamic test were carried out in the same visit. 66 67 4 RESULTS 68 69 A total of 105 nulliparous women were studied (51 spontaneous deliveries (SpD) and 54 70 vacuum assisted deliveries (VD)). Microtraumas were identified in 35.3% of SpD and 71 20.4% of VD. Macrotraumas (avulsion) were identified in 9.8% of SpD and 35.2% of 72 VD (p=0.006). No differences were found in USI between study groups or in relation to 73 the identification of LAM defects (19.2% in the no lesion group, 25% in macrotrauma 74 and 13.8% in microtrauma; P=not significant). Neither were significant differences 75 found in the results from the different study groups in the ICIQ-UI SF test (12.7±2.2 no 76 lesion group, 12.5±4.2 in macrotrauma and 13.25±4.8 in microtrauma; P=NS). 77 78 CONCLUSION 79 80 No difference was observed in USI between patients with and without LAM lesions 81 (microtrauma or macrotrauma) 36 months post delivery. 82 83 84 Keywords: Urinary stress incontinence, levator ani muscle, transperineal ultrasound, 85 pelvic floor, labor. 86 87 88 Brief Summary: No statistically significant differences were found between patients 89 with and without USI and LAM lesion (macrotrauma or microtrauma) 36 months post 90 delivery. 91 92 93 5 94 95 EVALUATION OF ISOLATED URINARY STRESS INCONTINENCE 96 ACCORDING TO THE TYPE OF LESION ON THE LEVATOR ANI MUSCLE 97 USING 3-4D TRANSPERINEAL ULTRASOUND 36 MONTHS POST-PARTUM. 98 99 100 INTRODUCTION 101 102 Pelvic floor disorders entail a very frequent group of pathologies which have a 103 significant impact on women's quality of life. Their importance lies mainly in their high 104 rate of incidence, which leads to the performance of 300,000 pelvic floor corrective 105 surgeries (pelvic organ prolapse and USI) per year (USA, 2003).1 Urinary incontinence 106 comprises 12–38% of all pelvic floor dysfunctions, hence the importance of its study.2 107 108 The multifactorial aetiology of pelvic floor dysfunctions is currently well established, 109 with pregnancy and vaginal delivery being described as the main factors determining 110 the onset of urinary incontinence and pelvic organ prolapse.3,4 During delivery, harm to 111 different pelvic floor structures is common. Levator ani muscle (LAM) avulsion seems 112 to be the most frequently identified lesion related to vaginal delivery.5 However, this 113 structure can suffer other kinds of lesions during delivery; these include traumatic 114 damage to the connective tissue and fascia, which can lead to a decreased contractility 115 of the LAM after delivery.6,7 This kind of lesion can be the result of muscle stretching, 116 direct trauma or pudendal nerve neuropraxia occurring during the delivery.8 117 118 6 Post-partum lesions of the pelvic floor may be categorised as macrotraumas and 119 microtraumas.9 Macrotrauma corresponds to LAM avulsion, defined as the 120 discontinuity of LAM muscle fibres at their pubic insertion,10 present in 13–36% of 121 women after vaginal delivery.9,11 On the other hand, microtrauma, defined as a 20% or 122 higher urogenital hiatus increase during Valsalva in the absence of avulsion, was present 123 in 30% of the women.9 Several authors have identified these defects as early indicators 124 for future USI and pelvic organ prolapse. 12–14 125 126 Although these lesions may be diagnosed by clinical evaluation, imaging techniques are 127 a more objective tool in establishing a correct diagnosis. Three-dimensional 128 transperineal ultrasound (3D-TpUS) and magnetic resonance imaging (MRI) are the 129 main imaging techniques used for the diagnosis of pelvic floor diseases.5,14,15 3D-TpUS 130 has proved to be useful in evaluating the functional anatomy of the pelvic floor, offering 131 an advanced space and time resolution through the capture of large numbers of images 132 in a short time.16-19 Moreover, 4D ultrasound assessment of the pelvic floor provides 133 quantitative and qualitative information on levator ani muscle (LAM) function and 134 lesions with higher sensitivity than digital exam.20 135 136 Our study group believes there may be an association between LAM defects and the 137 future onset of USI. Therefore, we propose assessing the relationship between LAM 138 lesions (macrotraumas and microtraumas) identified by 3/4D transperineal ultrasound 139 and the presence of USI 36 months post (vaginal) delivery. 140 141 MATERIALS AND METHOD 142 143 7 Prospective observational study with 168 nulliparous women with vaginal deliveries 144 recruited at the Valme Hospital (Seville, Spain) maternity unit between June 1 2012 and 145 December 31 2012. Study population constituted of volunteer patients who met criteria 146 and who were added consecutively (Figure 1) after being informed of the basis of the 147 study and signing informed consent. The trial received the approval from the 148 Andalusian regional government’s biomedical research ethics committee under the code 149 3004/2012. 150 151 All recruited patients were nulliparous, at term gestation (37–42 weeks), without prior 152 pelvic floor corrective surgery, with foetus in cephalic presentation and had either had a 153 spontaneous vaginal delivery (SpD) or required instrumentation with vacuum to 154 complete foetal extraction (VD). Patients who met study criteria were recruited during 155 the first 24 horas post-partum. 156 157 Pregnancies with severe maternal (preeclampsia, uncontrolled gestational diabetes, 158 grade 3–4 maternal cardiomyopathy, maternal endocrine or neurological disease, severe 159 maternal infection, maternal respiratory or orthopedic disorder) or foetal pathology 160 (structural malformation, chromosomopathy, foetal infection, isoimmunisation, 161 intrauterine growth restriction, hydrops) were excluded. In order to carry out a specific 162 evaluation of isolated USI, women complaining of symptoms of urinary urgency 163 incontinence or pelvic organ prolapse in the 36 months prior to ultrasound evaluation 164 were also excluded. 165 166 Deliveries were assisted by maternity unit staff with a minimum of five years 167 experience in obstetric practice. In all VD cases, a metal vacuum (Malström 50mm. 168 14 was the highest possible with the minimum number of patient losses. 318 319 This might contradict previous studies that doubted whether macrotrauma or 320 microtrauma impact the presence of isolated USI post-partum.24–26 However, we 321 consider a significant limitation to our study to be the low number of patients with USI 322 symptoms, which we believe may explain the lack of statistically significant differences 323 between study groups (no lesion, macrotrauma, microtrauma) according to the presence 324 or absence of USI. Because of this, we believe this study could trigger future 325 investigation in this area involving studies with larger number of patients. We also 326 consider a limitation to our study the fact of having lost such a high number of patients 327 due to the delay of the evaluation (36 months postpartum), reason why we believe that 328 carrying out the evaluation at 24 months postpartum would be more adequate. 329 Furthermore, another drawback of our study is excluding other pelvic floor pathologies 330 other than USI, as we consider that the inclusion of these kind of patients in our study 331 would reinforce our results. 332 333 In conclusion, we observed no differences in the presence of USI symptoms at 36 334 months post-partum in patients with and without LAM lesions (microtrauma or 335 macrotrauma). 336 337 15 References: 338 1. Boyles SH, Weber AM, Meyn L. Procedures for pelvic organ prolapse in the 339 United States, 1979-1997. Am J Obstet Gynecol. 2003;188:108-115. 340 2. 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Santoro GA, Wieczorek AP, Dietz HP, Mellgren A, Sultan A, Shobeiri SA, et al. 413 State of the art: an integrated approach to pelvic floor ultrasonography. 414 Ultrasound Obstet Gynecol 2011; 37: 381–96. 415 28. Eisenberg VH, Chantarasorn V, Shek KL, Dietz HP. Does levator ani injury 416 affect cystocele type?.Ultrasound Obstet Gynecol 2010; 36: 618–623. 417 29. Wu QK, MAO XY, Luo LM, Ying T, Li Q, Teng YC. Characteristics of pelvic 418 diaphragm hiatus in pregnant women with stress urinary incontinence detected 419 by transperineal three-dimensional ultrasound. Zhonghua Fu Chan Ke Za Zhi. 420 2010;45(5):326-30. 421 30. Stachowicz N, Stachowicz S, Smolen A, Morawska D, Kotarski J. Sonographic 422 evaluation of the levator ani muscle in women with stress urinary incontinence. 423 Ginekol Pol. 2012;83(9):669-73. 424 31. Hantoushzadeh S, Javadian P, Shariat M, Salmanian B, Ghazizadeh S, Aghssa 425 M. Stress urinary incontinence: pre-pregnancy history and effects of mode of 426 delivery on its postpartum persistency. Int J Urogynecol. 2011;22(6):651-5. doi: 427 10.1007/s00192-010-1335-6. 428 429 430 19 431 Figure 1: shows the process of capturing patients. 432 433 434 435 20 436 Image 1. Represents measures obtained at minimal dimension plane. A. Shows antero 437 posterior diameters of levator hiatus area (1), define as the distance between the 438 posterior region of pubic symphysis and LAM’s anterior region; and the transverse 439 diameters of levator hiatus area (2), which is the distance between the inner borders of 440 LAM at its pubic insertion. B. Measurement of levator hiatus area (3), describe as the 441 area that limits the anterior section with the posterior area of pelvic bones’ inferior 442 branches. C. LAM’s area (4) at the minimal dimension plane. 443 444 Image 2. Bilateral avulsion showing a defect at the insertion on three central planes (red 445 arrows). 446 21 447 22 448 Table 1. Gestational and intrapartum features of the study group. 449 450 Media (± DT) o % No lesion (n=52) Macrotrauma (n=24) Microtraumas (n=29) p Age 29.29 (±5.17) 33.04 (±3.75) 29.14 (±5.46) P=0.014 Gestational age 39.40 (±1.11) 38.33 (±1.20) 39.10 (±1.21) NS BMI 23.28 (±3.49) 24.10 (±3.10) 25.03 (±4.41) NS Epidural 94.23% (49/52) 91.67% (22/24) 82.76% (24/29) NS Epidural period (min) 368.82 (±165.19) 383.18 (±150.26) 364.25 (±209.13) NS Period of 2nd stage of labour (min) 102.56 (±70.76) 120.42 (±107.95) 102.48 (±57.69) NS Episiotomy 67.31% (35/52) 91.67% (22/24) 51.72% (15/29) P=0.007 Perineal tear 40.38% (21/52) 54.17% (13/24) 34.48% (10/29) NS Grade I 15.38% (8/52) 12.5% (3/24) 24.13% (7/29) Grade II 15.38% (8/52) 25% (6/24) 6.9% (2/29) NS Grade III 9.62% (5/52) 16.67% (4/24) 3.45% (1/29) Newborn weight (kg) 3241.7 (±409.59) 3409.79 (±408.55) 3185.69 (±357.11) NS NS: No statistical significance. 451 23 452 Table 2. Type of lesion according to delivery, hiatus measures and clinical incontinence. 453 Media (± DT) o % No lesion (n=52) Macrotauma (n=24) Microtraumas (n=29) P Delivery Vaginal 54.9%(28/51) 9.8%(5/51) 35.3%(18/51) P=0.006 Vacuum 44.4%(24/54) 35.2%(19/54) 20.4%(11/54) APD LAM’s hiatus at rest (mm) 64.56±7.41 68.28±7.83 61.79±6.50 P=0.007 APD LAM’s hiatus on Valsalva (mm) 65.19±8.01 72.88±7.22 68.84±7.93 P=0.001 APD LAM’s hiatus in contraction (mm) 61.46±6.96 65.59±7.80 58.97±7.35 P=0.005 TD LAM’s hiatus at rest (mm) 38.74±5.23 51.23±10.62 37.27±4.67 P<0.0005 TD LAM’s hiatus Valsalva (mm) 39.27±5.42 54.71±10.23 41.83±4.00 P<0.0005 TD LAM’s hiatus in contraction (mm) 38.54±5.87 51.77±9.17 37.89±4.53 P<0.0005 Area of LAM’s hiatus at rest (cm2) 17.16±2.91 20.29±4.41 15.60±2.69 P<0.0005 Area of LAM’s hiatus on Valsalva (cm2) 17.72±3.65 23.79±4.41 20.40±3.63 P<0.0005 Area of LAM’s hiatus in contraction (cm2) 16.28±3.35 20.14±4.10 15.65±2.87 P<0.0005 LAM’s área (cm2) 12.68±3.06 13.30±2.90 12.44±2.78 NS Urinary incontinence 19.2%(10/52) 16,7%(4/24) 20,7%(6/29) NS ICIQ-UI SF 12.7±2.2 12.5±4.2 13.2±4.8 NS APD: Antero posterior diameter; TD: transverse diameter; LAM: levator ani muscle; 454 NS: No statistical significance. 455 1 Tabla 3: Biometric parameters of the levator´s hiatus according absent or present the 1 stress urinary incontinence. 2 Media (± DT) o % Stress urinary incontinence. Absent (n:85) Stress urinary incontinence. Present (n:20) p Delivery Vaginal 88.2%(45/51) 11.8%(6/51) NS Vacuum 74.1%(40/54) 25.9%(14/54) APD LAM’s hiatus at rest (mm) 64.2±7.36 66.6±8.3 NS APD LAM’s hiatus on Valsalva (mm) 67.5±8.2 69.8±8.9 NS APD LAM’s hiatus in contraction (mm) 61.7±7.4 61.9±8.5 NS TD LAM’s hiatus at rest (mm) 41.7±8.5 39.2±9.1 NS TD LAM’s hiatus on Valsalva (mm) 44.0±8.9 41.3 ±8.9 NS TD LAM’s hiatus in contraction (mm) 41.9±8.6 38.9 ±8.3 NS Area of LAM’s hiatus at rest (cm2) 17.5±3.7 17.3±3.4 NS Area of LAM’s hiatus on Valsalva (cm2) 19.9±4.5 19.8±4.5 NS Area of LAM’s hiatus in contraction (cm2) 17.1±3.7 16.4±4.1 NS LAM’s area (cm2) 12.5±3.0 13.7±2.5 NS APD: Antero posterior diameter; TD: transverse diameter; LAM: levator ani muscle; 3 NS: No statistical significance. 4 5 Table 3