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He X, Du Q, Chang L, Jiang Y, Dou W, Pylypenko D, Yu D, Wang Q, Guo Y, Wang F. Analysis of minimal levator ani hiatus area based on MRI in female adults without pelvic floor dysfunction at different age groups. Arch Gynecol Obstet 2024; 309:2183-2191. [PMID: 37926730 DOI: 10.1007/s00404-023-07253-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/27/2023] [Indexed: 11/07/2023]
Abstract
PURPOSE To investigate the association of minimal levator ani hiatus area with age in female adults without pelvic floor dysfunction. METHODS 532 female subjects aged 18 ~ 90 years without pelvic floor dysfunction, divided into four groups (Group A, 18 ~ 29 years old; Group B, 30 ~ 39 years old; Group C, 40 ~ 49 years old; Group D, ≥ 50 years old) based on age, underwent traditional pelvic two-dimensional (2D) T2-weighted imaging (T2WI) axial to the body (AxB) for measuring the minimal levator ani hiatus area. 39 female volunteers were re-recruited to undergo both traditional pelvic 2D T2WI AxB and three-dimensional (3D) T2WI. An axial plane parallel to the direction of the puborectalis muscle (AxPRM) was acquired based on 3D T2WI. The difference of levator ani hiatus area measured on AxB and AxPRM images in 39 female volunteers was compared by one-sample t test, to verify if minimal levator ani hiatus area can be acquired on the traditional pelvic 2D T2WI AxB images. Spearman analysis evaluated the association of minimal levator ani hiatus area with age and the rank-sum test analyzed the area differences among four age groups. RESULTS Female age was positively correlated with minimal levator ani hiatus area (r = 0.23; p < 0.001). The minimal levator ani hiatus areas of 532 subjects were: 15.17 ± 1.77 cm2 in Group A, 15.52 ± 2.21 cm2 in Group B, 16.03 ± 2.16 cm2 in Group C, and 16.40 ± 2.10 cm2 in Group D. ANOVA showed significant statistical differences among four age groups (F = 7.519, p < 0.0001). Significant differences in minimal levator ani hiatus areas were found between Group A and Group C (p = 0.0491), Group A and Group D (p = 0.0007), and Group B and Group D (p < 0.001). There was no statistical difference in minimal levator ani hiatus areas measured on AxB and AxPRM images in 39 female volunteers (p = 0.1000). There were no statistical difference in minimal levator ani hiatus areas between nulliparous and multiparous group for each age group (all p > 0.05). CONCLUSIONS Based on a large sample, this study summarized the minimum levator ani hiatus area of female adults without pelvic floor dysfunction in different age groups. We found significant differences among different age groups. In addition, a positive correlation was found between age and the minimum levator ani hiatus area. These findings can provide reference criteria for diagnosing pelvic organ prolapse in female adults of different age groups.
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Affiliation(s)
- Xiaoyi He
- Department of Radiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, 250012, Shandong, China
- Department of Radiology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250001, Shandong, China
| | - Qian Du
- Department of Radiology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250001, Shandong, China
| | - Lingyu Chang
- Department of Radiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, 250012, Shandong, China
| | - Yan Jiang
- Department of Radiology, Yishui County People's Hospital, Linyi, 276499, Shandong, China
| | - Weiqiang Dou
- MR Research, GE Healthcare, Beijing, 10076, China
| | | | - Dexin Yu
- Department of Radiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, 250012, Shandong, China
| | - Qing Wang
- Department of Radiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, 250012, Shandong, China
| | - Yiting Guo
- Department of Radiology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250001, Shandong, China
| | - Fang Wang
- Department of Radiology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, 250012, Shandong, China.
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Qu E, Wu S, Zhang M, Huang Z, Zheng Z, Zhang X. Validation of a built-in software in automatically reconstructing the tomographic images of the levator ani muscle. Int Urogynecol J 2024; 35:175-181. [PMID: 38019307 DOI: 10.1007/s00192-023-05686-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 10/31/2023] [Indexed: 11/30/2023]
Abstract
INTRODUCTION AND HYPOTHESIS Transperineal ultrasound (TPUS) is an effective tool for evaluating the integrity of the levator ani muscle (LAM). Several operating steps are required to obtain the standard multi-slice image of the LAM, which is experience dependent and time consuming. This study was aimed at evaluating the feasibility and reproducibility of the built-in software, Smart-pelvic™, in reconstructing standard tomographic images of LAM from 3D/4D TPUS volumes. METHODS This study was conducted at a tertiary teaching hospital, enrolling women who underwent TPUS. Tomographic images of the LAM were automatically reconstructed by Smart-pelvicTM and rated by two experienced observers as standard or nonstandard. The anteroposterior diameter (APD) of the levator hiatus was also measured on the mid-sagittal plane of the automatically and manually reconstructed images. The APD measurements of each approach were compared using Bland-Altman plots, and interclass correlation coefficient (ICC) was used to evaluate intra- and inter-observer reproducibility. Meanwhile, the time taken for the reconstruction process of both methods was also recorded. RESULTS The ultrasound volume of a total of 104 patients were included in this study. Using Smart-pelvicTM, the overall success rate of the tomographic image reconstruction was 98%. Regarding measurements of APD, the ICC between the automatic and manual reconstruction methods was 0.99 (0.98, 0.99). The average time taken for reconstruction per case was 2.65 ± 0.52 s and 22.08 ± 3.45 s, respectively. CONCLUSIONS Using Smart-pelvicTM to reconstruct tomographic images of LAM is feasible, and it can promote TPUS by reducing operator dependence and improving examination efficiency in a clinical setting.
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Affiliation(s)
- Enze Qu
- Department of Ultrasound, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, Guangdong Province, China
| | - Shuangyu Wu
- Department of Ultrasound, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, Guangdong Province, China
| | - Man Zhang
- Department of Ultrasound, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, Guangdong Province, China
| | - Zeping Huang
- Department of Ultrasound, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, Guangdong Province, China
| | - Zhijuan Zheng
- Department of Ultrasound, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, Guangdong Province, China
| | - Xinling Zhang
- Department of Ultrasound, Third Affiliated Hospital of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, Guangdong Province, China.
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Ghafoor S, Beintner-Skawran SM, Stöckli G, Betschart C, Reiner CS. Pelvic organ movements in asymptomatic nulliparous and symptomatic premenopausal women with pelvic organ prolapse in dynamic MRI: a feasibility study comparing midsagittal single-slice with multi-slice sequences. Abdom Radiol (NY) 2023; 48:2658-2671. [PMID: 37208547 PMCID: PMC10333376 DOI: 10.1007/s00261-023-03944-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 05/21/2023]
Abstract
PURPOSE To compare multi-slice (MS) MRI sequences of the pelvis acquired at rest and straining to dynamic midsagittal single-slice (SS) sequences for the assessment of pelvic organ prolapse (POP). METHODS This IRB-approved prospective single-center feasibility study included 23 premenopausal symptomatic patients with POP and 22 asymptomatic nulliparous volunteers. MRI of the pelvis at rest and straining was performed with midsagittal SS and MS sequences. Straining effort, visibility of organs and POP grade were scored on both. Organ points (bladder, cervix, anorectum) were measured. Differences between SS and MS sequences were compared with Wilcoxon test. RESULTS Straining effort was good in 84.4% on SS and in 64.4% on MS sequences (p = 0.003). Organ points were always visible on MS sequences, whereas the cervix was not fully visible in 31.1-33.3% on SS sequences. At rest, there were no statistically significant differences of organ point measurements between SS and MS sequences in symptomatic patients. At straining, positions of bladder, cervix, and anorectum were + 1.1 cm (± 1.8 cm), - 0.7 cm (± 2.9 cm), and + 0.7 cm (± 1.3 cm) on SS and + 0.4 mm (± 1.7 cm), - 1.4 cm (± 2.6 cm), and + 0.4 cm (± 1.3 cm) on MS sequences (p < 0.05). Only 2 cases of higher-grade POP were missed on MS sequences (both with poor straining effort). CONCLUSION MS sequences increase the visibility of organ points compared to SS sequences. Dynamic MS sequences can depict POP if images are acquired with sufficient straining effort. Further work is needed to optimize the depiction of the maximum straining effort with MS sequences.
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Affiliation(s)
- Soleen Ghafoor
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland
- University of Zurich, Zurich, Switzerland
| | - Stephan M Beintner-Skawran
- Department of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland
- University of Zurich, Zurich, Switzerland
| | - Gian Stöckli
- Department of Gynecology, University Hospital Zurich, Frauenklinikstrasse 10, 8091, Zurich, Switzerland
- University of Zurich, Zurich, Switzerland
| | - Cornelia Betschart
- Department of Gynecology, University Hospital Zurich, Frauenklinikstrasse 10, 8091, Zurich, Switzerland
- University of Zurich, Zurich, Switzerland
| | - Cäcilia S Reiner
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland.
- University of Zurich, Zurich, Switzerland.
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Chill HH, Martin LC, Abramowitch SD, Rostaminia G. Multimodal measurements of levator bowl volume in nulligravid asymptomatic women: endovaginal ultrasound versus MRI. Int Urogynecol J 2023; 34:1627-1633. [PMID: 36656345 DOI: 10.1007/s00192-022-05441-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/02/2022] [Indexed: 01/20/2023]
Abstract
INTRODUCTION AND HYPOTHESIS Measurements of levator bowl volume using advanced imaging, may be predictive of pelvic floor muscle function. The aim of this study was to compare the volume of the levator bowl using both magnetic resonance imaging (MRI) and endovaginal ultrasound (EVU) of healthy asymptomatic women. METHODS All participants underwent a comprehensive interview including completion of the Pelvic Floor Distress Inventory Questionnaire-20 questionnaire, pelvic examination with a pelvic organ prolapse quantification evaluation, MRI, and EVU. The pelvic floor was segmented using Slicer and the MRI segmentations were trimmed using two methods: soft-tissue landmarks and the field of view (FOV) of the ultrasound volume. The levator bowl volume of the 3D segmented shapes was measured using Blender's 3D printing toolkit. Normality was tested using the Shapiro-Wilks test and comparisons were made using self-paired t tests. RESULTS The final analysis included 19 patients. Levator bowl volume measured via MRI was larger than that measured in EVU (46.1 ± 7.9 cm3 vs 27.4 ± 5.9 cm3, p<0.001). Reducing the FOV of the MRI to that of EVU caused the MRI volume to be much closer to the EVU volume (35.5 ± 3.3 cm3 vs 27.4 ± 5.9 cm3, p<0.001); however, it remained significantly larger. CONCLUSION Levator bowl volume measured using MRI was larger than that measured using EVU no matter the method of delineation of the levator muscles. Although EVU is safe, cheap, and easy to perform, it captures a smaller volume of levator bowel than MRI.
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Affiliation(s)
- Henry H Chill
- Female Pelvic Medicine and Reconstructive Surgery (FPMRS), Division of Urogynecology, University of Chicago, Northshore University HealthSystem, 9650 Gross Point Road, Suite 3900, Skokie, IL, 60076, USA.
| | - Liam C Martin
- Translational Biomechanics Laboratory, Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Steven D Abramowitch
- Translational Biomechanics Laboratory, Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ghazaleh Rostaminia
- Female Pelvic Medicine and Reconstructive Surgery (FPMRS), Division of Urogynecology, University of Chicago, Northshore University HealthSystem, 9650 Gross Point Road, Suite 3900, Skokie, IL, 60076, USA
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Guo M, Zbar AP, Wu Y. Imaging the levator ani and the puborectalis muscle: implications in understanding regional anatomy, physiology and pathology. Scand J Gastroenterol 2023; 58:1295-1308. [PMID: 37309141 DOI: 10.1080/00365521.2023.2220458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/17/2023] [Accepted: 05/28/2023] [Indexed: 06/14/2023]
Abstract
Purpose:To review the findings of recent dynamic imaging of the levator ani muscle in order to explain its function during defecation. Historical anatomical studies have suggested that the levator ani initiates defecation by lifting the anal canal, with conventional dissections and static radiologic imagery having been equated with manometry and electromyography.Materials and methods:An analysis of the literature was made concerning the chronological development of imaging modalities specifically designed to assess pelvic floor dynamics. Comparisons are made between imaging and electromyographic data at rest and during provocative manoeuvres including squeeze and strain.Results:The puborectalis muscle is shown distinctly separate from the levator ani and the deep external anal sphincter. In contrast to conventional teaching that the levator ani initiates defecation by lifting the anus, dynamic illustration defecography (DID) has confirmed that the abdominal musculature and the diaphragm instigate defecation with the transverse and vertical component portions of the levator ani resulting in descent of the anus. Current imaging has shown a tendinous peripheral structure to the termination of the conjoint longitudinal muscle, clarifying the anatomy of the perianal spaces. Planar oXy defecography has established patterns of movement of the anorectal junction that separate controls from those presenting with descending perineum syndrome or with anismus (paradoxical puborectalis spasm).Conclusions:Dynamic imaging of the pelvic floor (now mostly with MR proctography) has clarified the integral role of the levator ani during defecation. Rather than lifting the rectum, the muscle ensures descent of the anal canal.
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Affiliation(s)
- Maolin Guo
- Department of Radiology, PLA 989 Hospital, Luoyang, P.R. China
| | - Andrew P Zbar
- Department of Neuroscience and Anatomy, University of Melbourne, Melbourne, Australia
| | - Yucen Wu
- Department of Neuroscience and Anatomy, University of Melbourne, Melbourne, Australia
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Cui C, Zhao Y, Cui D, Li N, Pan J, Shen W. In vivo evaluation of the levator ani muscle in primiparous women using diffusion tensor imaging and fiber tractography. Int J Gynaecol Obstet 2021; 157:663-670. [PMID: 34492120 DOI: 10.1002/ijgo.13897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 07/11/2021] [Accepted: 08/20/2021] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To characterize the levator ani muscle (LAM) injury after first vaginal delivery and investigate the clinical application of diffusion tensor imaging (DTI) and fiber tractography in evaluating the LAM. METHODS Fifty-eight primiparous women at 6 weeks after vaginal delivery and 27 nulliparous women as controls underwent T2-weighted sequence and DTI sequence of the pelvic floor. A LAM scoring system was used to characterize the morphological changes. Fiber tractography of each major subdivision of LAM was performed, followed by assessment of the quality of fiber tracking. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), fiber volume, and length were calculated. RESULTS Puborectalis and iliococcygeus injuries were observed in 30/58 (51.7%) and 10/58 (17.2%) primiparae, respectively. No LAM defects were identified in the control group. For the puborectalis, the FA values were lower (P = 0.010) and ADC values were higher (P = 0.024) in the primiparous group than in the control group. For the iliococcygeus, the fiber volume values were lower in the primiparous group than in the control group (P = 0.004). CONCLUSION Vaginal delivery can result in LAM injury at the puborectalis. DTI parameters can assist in the quantitative diagnosis of the LAM injury.
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Affiliation(s)
- Can Cui
- Department of Radiology, Affiliated JinHua Hospital, ZheJiang University School of Medicine (JinHua Municipal Central Hospital), JinHua, China
| | - Yujiao Zhao
- Department of Radiology, Tianjin First Center Hospital, Tianjin, China
| | - Dawei Cui
- Department of Obstetrics and Gynecology, Affiliated JinHua Hospital, ZheJiang University School of Medicine (JinHua Municipal Central Hospital), JinHua, China
| | - Na Li
- Department of Radiology, Shanghai Institute of Medical Imaging, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jiangfeng Pan
- Department of Radiology, Affiliated JinHua Hospital, ZheJiang University School of Medicine (JinHua Municipal Central Hospital), JinHua, China
| | - Wen Shen
- Department of Radiology, Tianjin First Center Hospital, Tianjin, China
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Rusavy Z, Paymova L, Kozerovsky M, Veverkova A, Kalis V, Kamel RA, Ismail KM. Levator ani avulsion: a Systematic evidence review (LASER). BJOG 2021; 129:517-528. [PMID: 34245656 DOI: 10.1111/1471-0528.16837] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND There is variation in the reported incidence rates of levator avulsion (LA) and paucity of research into its risk factors. OBJECTIVE To explore the incidence rate of LA by mode of birth, imaging modality, timing of diagnosis and laterality of avulsion. SEARCH STRATEGY We searched MEDLINE, EMBASE, CINAHL, AMED and MIDIRS with no language restriction from inception to April 2019. STUDY ELIGIBILITY CRITERIA A study was included if LA was assessed by an imaging modality after the first vaginal birth or caesarean section. Case series and reports were not included. DATA COLLECTION AND ANALYSIS RevMan v5.3 was used for the meta-analyses and SW SAS and STATISTICA packages were used for type and timing of imaging analyses. RESULTS We included 37 primary non-randomised studies from 17 countries and involving 5594 women. Incidence rates of LA were 1, 15, 21, 38.5 and 52% following caesarean, spontaneous, vacuum, spatula and forceps births, respectively, with no differences by imaging modality. Odds ratio of LA following spontaneous birth versus caesarean section was 10.69. The odds ratios for LA following vacuum and forceps compared with spontaneous birth were 1.66 and 6.32, respectively. LA was more likely to occur unilaterally than bilaterally following spontaneous (P < 0.0001) and vacuum-assisted (P = 0.0103) births but not forceps. Incidence was higher if assessment was performed in the first 4 weeks postpartum. CONCLUSIONS LA incidence rates following caesarean, spontaneous, vacuum and forceps deliveries were 1, 15, 21 and 52%, respectively. Ultrasound and magnetic resonance imaging were comparable tools for LA diagnosis. TWEETABLE ABSTRACT Levator avulsion incidence rates after caesarean, spontaneous, vacuum and forceps deliveries were 1, 15, 21 and 52%, respectively.
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Affiliation(s)
- Z Rusavy
- Department of Obstetrics and Gynaecology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.,Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.,Department of Obstetrics and Gynaecology, University Hospital, Pilsen, Czech Republic
| | - L Paymova
- Department of Obstetrics and Gynaecology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.,Department of Obstetrics and Gynaecology, University Hospital, Pilsen, Czech Republic
| | - M Kozerovsky
- Department of Obstetrics and Gynaecology, University Hospital, Pilsen, Czech Republic
| | - A Veverkova
- Department of Obstetrics and Gynaecology, University Hospital, Pilsen, Czech Republic
| | - V Kalis
- Department of Obstetrics and Gynaecology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.,Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.,Department of Obstetrics and Gynaecology, University Hospital, Pilsen, Czech Republic
| | - R A Kamel
- Maternal-Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Cairo University, Cairo, Egypt
| | - K M Ismail
- Department of Obstetrics and Gynaecology, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic.,Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic
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Korula DR, Chandramohan A, John R, Eapen A. Barium Defecating Proctography and Dynamic Magnetic Resonance Proctography: Their Role and Patient's Perception. J Clin Imaging Sci 2021; 11:31. [PMID: 34221640 PMCID: PMC8247951 DOI: 10.25259/jcis_56_2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/02/2021] [Indexed: 11/30/2022] Open
Abstract
Objectives: The objectives of the study were to compare the imaging findings and patient’s perception of barium defecating proctography and dynamic magnetic resonance (MR) proctography in patients with pelvic floor disorders. Material and Methods: This is a prospective study conducted on patients with pelvic floor disorders who consented to undergo both barium proctography and dynamic MR proctography. Imaging findings of both the procedures were compared. Inter-observer agreement (IOA) for key imaging features was assessed. Patient’s perception of these procedures was assessed using a short questionnaire and a visual analog scale. Results: Forty patients (M: F =19:21) with a mean age of 43.65 years and range of 21–75 years were included for final analysis. Mean patient experience score was significantly better for MR imaging (MRI) (p < 0.001). However, patients perceived significantly higher difficulty in rectal evacuation during MRI studies (p = 0.003). While significantly higher number of rectoceles (p = 0.014) were diagnosed on MRI, a greater number of pelvic floor descent (p = 0.02) and intra-rectal intussusception (p = 0.011) were diagnosed on barium proctography. The IOA for barium proctography was substantial for identifying rectoceles, rectal prolapse and for determining M line, p < 0.001. There was excellent IOA for MRI interpretation of cystoceles, peritoneoceles, and uterine prolapse and substantial to excellent IOA for determining anal canal length and anorectal angle, p < 0.001. The mean study time for the barium and MRI study was 12 minutes and 15 minutes, respectively. Conclusion: Barium proctography was more sensitive than MRI for detecting pelvic floor descent and intrarectal intussusception. Although patients perceived better rectal emptying with barium proctography, the overall patient experience was better for dynamic MRI proctography.
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Affiliation(s)
| | | | - Reetu John
- Department of Radiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Anu Eapen
- Department of Radiology, Christian Medical College, Vellore, Tamil Nadu, India
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Abstract
Pelvic floor dysfunction is a relatively common but often complex condition, presenting with a variety of clinical symptoms, especially when it involves multiple compartments. Clinical exam alone is often inadequate and requires a complementary imaging study. Magnetic resonance defecography (MRD) is an excellent noninvasive diagnostic study with its multiplanar capability, lack of ionizing radiation and excellent soft tissue resolution. It can identify both anatomic and functional abnormalities in the pelvic floor and specifically excels in its ability to simultaneously detect multicompartmental pathology and help with vital pre-operative assessment. This manuscript reviews the relevant anatomical landmarks, describes the optimal technique, highlights an approach to the interpretation of MRD, and provides an overview of the various pelvic floor disorders in the different anatomical compartments.
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10
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Abstract
The pelvic floor is composed of a network of muscles, ligaments, and fasciae, which provide active and passive support for the pelvic organs. Impairment of these pelvic floor elements can result in a variety of functional abnormalities and single or multicompartment organ prolapse. Knowledge of normal pelvic floor anatomy can aid the radiologist in understanding the complex nature of pelvic floor dysfunction and is important for comprehensive image interpretation. This article provides an overview of normal anatomy of the pelvic floor as seen on magnetic resonance imaging, ultrasound, and fluoroscopic studies performed in the evaluation of pelvic floor function.
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11
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Wu E, Kuehl TJ, Gendron JM, White W, Yandell PM. Pelvic floor changes in the first term pregnancy and postpartum period. Int Urogynecol J 2020; 32:1897-1905. [PMID: 32737534 DOI: 10.1007/s00192-020-04456-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/20/2020] [Indexed: 10/23/2022]
Abstract
OBJECTIVE To follow a prospective cohort of women during their first term pregnancy to elucidate the nature and timing of changes to the pelvic floor during pregnancy and after vaginal delivery. METHODS Enrolled subjects were evaluated at four time points with dynamic MRI, POP-Q examinations, and validated symptom questionnaires. The four assessments occurred during the first trimester (ePG), late third trimester (lPG), within a week after vaginal delivery (ePP), and three months postpartum (lPP). Two-dimensional T1-weighted MRI measurements included bladder descent and area of the levator hiatus at rest and during Valsalva maneuvers. Sample size of ten subjects was calculated for a power of 0.8 to detect a 20% change in bladder position with p < 0.05. Comparative statistical tests were used for parametric and non-parametric data, respectively. RESULTS Twelve subjects completed the study. At lPP, the bladder descent was increased (p = 0.03) at rest and with Valsalva compared to ePG. Levator hiatus area did not differ (p = 0.63) between time points at rest or with Valsalva. Median POP stage increased (p = 0.001) to 1.5 at lPP. Mean genital hiatus increased (p = 0.0003) at each time point. Higher scores were recorded on the UDI-6 (p < 0.001) and the PFDI-20 (p = 0.003) questionnaires at lPG and ePP, but returned to ePG levels by lPP. CONCLUSION Anatomic changes measured by dynamic MRI and POP-Q examinations demonstrate significant descent at 3 months postpartum. However, these anatomic changes did not significantly correlate with changes in symptoms.
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Affiliation(s)
- Emily Wu
- Baylor Scott & White Medical Center - Temple, 2401 South 31st Street, Temple, TX, 76508, USA.
| | - Thomas J Kuehl
- Baylor Scott & White Medical Center - Temple, 2401 South 31st Street, Temple, TX, 76508, USA
| | - Jilene M Gendron
- Baylor Scott & White Medical Center - Temple, 2401 South 31st Street, Temple, TX, 76508, USA
| | - Wendy White
- Baylor Scott & White Medical Center - Temple, 2401 South 31st Street, Temple, TX, 76508, USA
| | - Paul M Yandell
- Baylor Scott & White Medical Center - Temple, 2401 South 31st Street, Temple, TX, 76508, USA
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Tai JW, Sorkhi SR, Trivedi I, Sakamoto K, Albo M, Bhargava V, Rajasekaran MR. Evaluation of Age- and Radical-Prostatectomy Related Changes in Male Pelvic Floor Anatomy Based on Magnetic Resonance Imaging and 3-Dimensional Reconstruction. World J Mens Health 2020; 39:566-575. [PMID: 32648374 PMCID: PMC8255398 DOI: 10.5534/wjmh.200021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/29/2020] [Accepted: 05/02/2020] [Indexed: 02/06/2023] Open
Abstract
Purpose Puborectalis muscles (PRM) and ischiocavernosus muscles (ICM) play important roles in urinary continence and male erectile functions. Understanding of anatomy and surgical-injury related changes to these muscles is critical to monitor changes in continence or erectile function. Anatomical description of these muscles has undergone revisions because these conclusions were derived from cadavers. Our objectives were to: (i) elucidate male pelvic muscles by in-vivo magnetic resonance imaging (MRI) and 3-dimensional (3-D) reconstruction of these images and (ii) compare PRM and ICM thickness in healthy volunteers and symptomatic patients. Materials and Methods Healthy young male (mean age, 25 years; n=5), older male (age, 65–70 years; n=5), and post-prostatectomy patients with erectile dysfunction and urinary incontinence (age, 65–70 years; n=5) were scanned on a 3T-magnetic resonance scanner. Images were acquired from slices above urinary bladder base to urethra entry into penis. Pelvic bone, bladder/urethra, corpus cavernosum, ICM, PRM, and prostate were segmented. 3-D models of each structure were generated and assembled into composite images, and ICM and PRM thicknesses were calculated. Results We successfully reconstructed 3-D male pelvic floor anatomy including ICM, PRM, bladder, urethra, bulbospongiosus, corpus cavernosa, prostate and bones from the two groups. We documented significant reduction in PRM and ICM thickness in older men. Conclusions This is perhaps the first 3-D reconstruction of male pelvic floor structures based on in-vivo MRI in healthy and symptomatic patients. Observed reduction in PRM and ICM thickness is possibly due to age-related atrophy.
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Affiliation(s)
- Jesse W Tai
- Department of Urology, San Diego VA Healthcare System & University of California, San Diego, CA, USA
| | - Samuel R Sorkhi
- Department of Urology, San Diego VA Healthcare System & University of California, San Diego, CA, USA
| | - Ishika Trivedi
- Department of Urology, San Diego VA Healthcare System & University of California, San Diego, CA, USA
| | - Kyoko Sakamoto
- Department of Urology, San Diego VA Healthcare System & University of California, San Diego, CA, USA
| | - Michael Albo
- Department of Urology, San Diego VA Healthcare System & University of California, San Diego, CA, USA
| | - Valmik Bhargava
- Division of Cardiology, San Diego VA Healthcare System & University of California, San Diego, CA, USA
| | - Mahadevan Raj Rajasekaran
- Department of Urology, San Diego VA Healthcare System & University of California, San Diego, CA, USA.
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Yang Z, Xia Z, Li B, Yao X, Jin X, Wang X. Investigation of correlation between bony pelvis dimensions and pelvic organ prolapse in different compartments. Eur J Obstet Gynecol Reprod Biol 2020; 252:213-217. [PMID: 32622105 DOI: 10.1016/j.ejogrb.2020.06.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 06/08/2020] [Accepted: 06/15/2020] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To investigate the association between bony pelvis dimensions and anterior, apical, and posterior compartment pelvic organ prolapse (POP) and explore the mechanism of different types of POP from an anatomical point of view. STUDY DESIGN A total of 253 patients with POP were selected as the experimental group (138 patients with anterior compartment defect, 86 with apical compartment defect, and 29 with posterior compartment defect); 253 patients with uterine myoma constituted the control group. Their demographics were recorded, and anteroposterior diameters of the pelvic inlet, intertuberous diameter, and interspinous diameter were measured. One-way analysis of variance, least significant difference t-test, and Student's t-test were used to evaluate the pelvic measurements among the four groups. RESULTS The anteroposterior diameter of the pelvic inlet in the apical compartment POP group was smaller than that in the other groups (P < 0.05). Interspinous diameters in the anterior and apical groups were larger than those in the posterior POP and control groups (P < 0.05). Intertuberous diameter in the control group was smaller than that in the anterior and apical POP groups and larger than that in the posterior POP group (P < 0.05). CONCLUSION Women with apical compartment POP are more likely to have a smaller anteroposterior diameter. Larger interspinous and intertuberous diameters were associated with anterior and apical POP, and smaller intertuberous diameter was associated with posterior POP.
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Affiliation(s)
- Zhiqi Yang
- Department of Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Zhijun Xia
- Department of Gynecology, Shengjing Hospital of China Medical University, Shenyang, China.
| | - Baoxiang Li
- Department of Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xiao Yao
- Department of Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xin Jin
- Department of Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xiaoming Wang
- Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China
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Liu D, Adams M, Burdette EC, Diederich CJ. Dual-sectored transurethral ultrasound for thermal treatment of stress urinary incontinence: in silico studies in 3D anatomical models. Med Biol Eng Comput 2020; 58:1325-1340. [PMID: 32277340 DOI: 10.1007/s11517-020-02152-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 02/25/2020] [Indexed: 11/24/2022]
Abstract
The purpose of this study is to investigate the feasibility and performance of a stationary, non-focused dual-sectored tubular transurethral ultrasound applicator for thermal exposure of tissue regions adjacent to the urethra for treatment of stress urinary incontinence (SUI) through acoustic and biothermal simulations on 3D anatomical models. Parametric studies in a generalized tissue model over dual-sectored ultrasound applicator configurations (acoustic surface intensities, lateral active acoustic output sector angles, and durations) were performed. Selected configurations and delivery strategies were applied on 3D pelvic anatomical models. Temperature and thermal dose distributions on the target region and surrounding tissues were calculated. Endovaginal cooling was explored as a strategy to mitigate vaginal heating. The 75-90° dual-sectored transurethral tubular transducer (3.5 mm outer diameter (OD), 14 mm length, 6.5 MHz, 8.8-10.2 W/cm2) and 2-3-min sonication duration were selected from the parametric study for acoustic and biothermal simulations on anatomical models. The transurethral applicator with two opposing 75-90° active lateral tubular sectors can create two heated volumes for a total of up to 1.8 cm3 over 60 EM43 °C, with at least 10 mm radial penetration depth, 1.2 mm urethral sparing, and no lethal damage to the vagina and adjacent bone (< 60 EM43 °C). Endovaginal cooling can be applied to further reduce the vaginal wall exposure (< 15 EM43 °C). Simulations on 3D anatomical models indicate that dual-sectored transurethral ultrasound applicators can selectively heat pelvic floor tissue lateral to the mid-urethra in short treatment durations, without damaging adjacent vaginal and bone tissues, as a potential alternative treatment option for stress urinary incontinence. Graphical abstract Schema for in silico investigation of transurethral ultrasound thermal therapy applicator for minimally invasive treatment of SUI.
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Affiliation(s)
- Dong Liu
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | - Matthew Adams
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | | | - Chris J Diederich
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA.
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15
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Juliato CRT, Santos‐Junior LC, Castro EB, Dertkigil SS, Brito LGO. Vaginal axis after abdominal sacrocolpopexy versus vaginal sacrospinous fixation—a randomized trial. Neurourol Urodyn 2019; 38:1142-1151. [DOI: 10.1002/nau.23970] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 02/10/2019] [Accepted: 02/20/2019] [Indexed: 12/19/2022]
Affiliation(s)
| | - Luiz Carlos Santos‐Junior
- Department of Obstetrics and Gynecology, School of Medical SciencesUniversity of CampinasSão Paulo Brazil
| | - Edilson Benedito Castro
- Department of Obstetrics and Gynecology, School of Medical SciencesUniversity of CampinasSão Paulo Brazil
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Comparing 3-Dimensional Ultrasound to 3-Dimensional Magnetic Resonance Imaging in the Detection of Levator Ani Defects. Female Pelvic Med Reconstr Surg 2019; 24:295-300. [PMID: 28953075 DOI: 10.1097/spv.0000000000000485] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE The aim of this study was to compare the detection of levator ani defects (LAD) between 3-dimensional (3D) ultrasound (US) and 3D magnetic resonance imaging (MRI). METHODS This is a secondary analysis of the Pelvic Floor Nerve Injury Following Childbirth Study. Nulliparous women underwent a standardized protocol of pelvic floor evaluations between January 2008 and December 2013, prior to pregnancy (V1) and at 2 points postpartum: 6 weeks (V2) and 6 months (V3). Those women who underwent a high-resolution 3D MRI pelvic floor sequence were selected. Comparisons were made to concomitantly acquired 3D perineal US. Eight tomographic slices were examined in the axial plane, each side independently scored with 0 (no defect) or 1 (defect). A similar tomographic approach was applied to the MRI. For both MRI and US, the right and left sides were each scored. A total score of 0 to 8 was given to each side. A dichotomous variable "complete LAD" was defined. Cohen κ was used as a measurement of agreement of complete LAD between MRI and US. Kendall τ b was used to correlate total scores. RESULTS On the right side, 80 (90%) of 89 pairs were in agreement (concordant in the diagnosis or not of a "defect"). On the left side, 72 (81%) of 89 pairs were in agreement. Correlations (Cohen κ) of complete LAD were 0.65 (P < 0.001) on the right and 0.37 (P < 0.001) on the left. Correlations of total scores were 0.47 (P < 0.001) on the right and 0.41 (P < 0.001) on the left. CONCLUSIONS Moderate agreement was found between 3D US and 3D MRI LAD detection. More LADs and discordance were seen on the left.
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Sheth VR, Duran P, Wong J, Shah S, Du J, Christman KL, Chang EY, Alperin M. Multimodal imaging assessment and histologic correlation of the female rat pelvic floor muscles' anatomy. J Anat 2019; 234:543-550. [PMID: 30740685 DOI: 10.1111/joa.12943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2018] [Indexed: 10/27/2022] Open
Abstract
Pelvic floor disorders negatively impact millions of women worldwide. Although there is a strong epidemiological association with childbirth, the mechanisms leading to the dysfunction of the integral constituents of the female pelvic floor, including pelvic floor skeletal muscles, are not well understood. This is in part due to the constraints associated with directly probing these muscles, which are located deep in the pelvis. Thus, experimental models and non-invasive techniques are essential for advancing knowledge of various phenotypes of pelvic floor muscle injury and pathogenesis of muscle dysfunction, as well as developing minimally invasive approaches for the delivery of novel therapeutics. The most widely used animal model for pelvic floor disorders is the rat. However, the radiological anatomy of rat pelvic floor muscles has not been described. To remedy this gap, the current study provides the first detailed description of the female rat pelvic floor muscles' radiological appearance on MR and ultrasound images, validated by correlation with gross anatomy and histology. We also demonstrate that ultrasound guidance can be used to target rat pelvic floor muscles for possible interventional therapies.
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Affiliation(s)
- Vipul R Sheth
- Department of Radiology, University of California San Diego, La Jolla, CA, USA
| | - Pamela Duran
- Department of Bioengineering, Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jonathan Wong
- Department of Radiology, University of California San Diego, La Jolla, CA, USA.,Radiology Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - Sameer Shah
- Department of Orthopedic Surgery, University of California San Diego, La Jolla, CA, USA
| | - Jiang Du
- Department of Radiology, University of California San Diego, La Jolla, CA, USA
| | - Karen L Christman
- Department of Bioengineering, Sanford Consortium for Regenerative Medicine, University of California San Diego, La Jolla, CA, USA
| | - Eric Y Chang
- Department of Radiology, University of California San Diego, La Jolla, CA, USA.,Radiology Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - Marianna Alperin
- Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Diego, La Jolla, CA, USA
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18
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Wakaiki T, Tanaka T, Shimatani K, Kurita Y, Iida T. Individualization of Musculoskeletal Model for Analyzing Pelvic Floor Muscles Activity Based on Gait Motion Features. JOURNAL OF ROBOTICS AND MECHATRONICS 2018. [DOI: 10.20965/jrm.2018.p0991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Stress urinary incontinence (SUI) is a typical quality of life disease in women. The strengthening of the pelvic floor muscle (PFM) is considered effective to prevent this. Specifically, PFM activity is affected by individual pelvic shape and posture. Therefore, it is necessary to analyze muscle activity by considering the individual differences. In this study, individual pelvic alignment was estimated from the feature values of natural gait via multiple regression analysis. In addition, individual pelvic feature points were derived from X-ray images and used to deform the standard model to obtain individual pelvic shapes. Results indicate that the residual averages of the estimated feature angles were less than 2° in most cases. Subsequently, measurements of the pelvis were obtained via MRI to evaluate the estimated pelvis shape. The results indicate that individual adaptation leads to muscle attachment positions, which are important in the muscle activity analysis, and closer to the true MRI value when compared to that of the standard pelvic model.
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19
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Liu D, Adams MS, Burdette EC, Diederich CJ. Transurethral high-intensity ultrasound for treatment of stress urinary incontinence (SUI): simulation studies with patient-specific models. Int J Hyperthermia 2018; 34:1236-1247. [PMID: 29566562 PMCID: PMC6136964 DOI: 10.1080/02656736.2018.1456679] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/16/2018] [Accepted: 03/17/2018] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Stress urinary incontinence (SUI) is prevalent in adult women, attributed to weakened endopelvic supporting tissues, and typically treated using drugs and invasive surgical procedures. The objective of this in silico study is to explore transurethral high-intensity ultrasound for delivery of precise thermal therapy to the endopelvic tissues adjacent to the mid-urethra, to induce thermal remodeling as a potential minimally invasive treatment alternative. METHODS 3D acoustic (Rayleigh-Sommerfeld) and biothermal (Pennes bioheat) models of the ultrasound applicator and surrounding tissues were devised. Parametric studies over transducer configuration [frequency, radius-of-curvature (ROC)] and treatment settings (power, duration) were performed, and select cases on patient-specific models were used for further evaluation. Transient temperature and thermal dose distributions were calculated, and temperature and dose metrics reported. RESULTS Configurations using a 5-MHz curvilinear transducer (3.5 × 10 mm, 28 mm ROC) with single 90 s sonication can create heated zones with 11 mm penetration (>50 °C) while sparing the inner 1.8 mm (<45 °C) radial depth of the urethral mucosa. Sequential and discrete applicator rotations can sweep out bilateral coagulation volumes (1.4 W power, 15° rotations, 600 s total time), produce large volumetric (1124 mm³ above 60 EM43 °C) and wide angular (∼50.5° per lateral sweep) coverage, with up to 15.6 mm thermal penetration and at least 1.6 mm radial urethral protection (<5 EM43 °C). CONCLUSION Transurethral applicators with curvilinear ultrasound transducers can deliver spatially selective temperature elevations to lateral mid-urethral targets as a possible means to tighten the endopelvic fascia and adjacent tissues.
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Affiliation(s)
- Dong Liu
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | - Matthew S. Adams
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
| | | | - Chris J. Diederich
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, USA
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20
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Chamié LP, Ribeiro DMFR, Caiado AHM, Warmbrand G, Serafini PC. Translabial US and Dynamic MR Imaging of the Pelvic Floor: Normal Anatomy and Dysfunction. Radiographics 2018; 38:287-308. [PMID: 29320316 DOI: 10.1148/rg.2018170055] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Pelvic floor dysfunction (PFD) is a common condition that typically affects women older than 50 years and decreases the quality of life. Weakening of support structures can involve all three pelvic compartments and cause a combination of symptoms, including constipation, urinary and fecal incontinence, obstructed defecation, pelvic pain, perineal bulging, and sexual dysfunction. The causes of PFD are complex and multifactorial; however, vaginal delivery is considered a major predisposing factor. Physical examination alone is limited in the evaluation of PFD; it frequently leads to an underestimation of the involved compartments. Imaging has an important role in the clinical evaluation, yielding invaluable information for patient counseling and surgical planning. Three- and four-dimensional translabial ultrasonography (US) is a relatively new imaging modality with high accuracy in the evaluation of PFD such as urinary incontinence, pelvic organ prolapse, and puborectalis avulsion. Evaluation of mesh implants is another important indication for this modality. Dynamic magnetic resonance (MR) imaging of the pelvic floor is a well-established modality for pelvic floor evaluation, with high-resolution images yielding detailed anatomic information and dynamic sequences yielding functional data. Specific protocols and dedicated image interpretation are required with both of these imaging methods. In this article, the authors review the normal anatomy of the female pelvic floor by using a practical approach, discuss the roles of translabial US and MR imaging in the investigation of PFD, describe the most appropriate imaging protocols, and illustrate the most common imaging findings of PFD in the anterior, middle, and posterior compartments of the pelvis. Online supplemental material is available for this article. ©RSNA, 2018.
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Affiliation(s)
- Luciana P Chamié
- From the Department of Diagnostic Imaging, Chamié Imagem da Mulher, Rua Casa do Ator, 1117, cj 72, São Paulo, SP 04546-004, Brazil (L.P.C.); Department of Diagnostic Imaging, Fleury Medicina e Saúde, São Paulo, Brazil (L.P.C., A.H.M.C., G.W.); Department of Female Reconstructive Surgery, Clínica Dr Duarte Miguel Ferreira Rodrigues Ribeiro, São Paulo, Brazil (D.M.F.R.R.); and Instituto de Radiologia-INRAD (A.H.M.C.) and Department of Gynecology (P.C.S.), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Duarte Miguel Ferreira Rodrigues Ribeiro
- From the Department of Diagnostic Imaging, Chamié Imagem da Mulher, Rua Casa do Ator, 1117, cj 72, São Paulo, SP 04546-004, Brazil (L.P.C.); Department of Diagnostic Imaging, Fleury Medicina e Saúde, São Paulo, Brazil (L.P.C., A.H.M.C., G.W.); Department of Female Reconstructive Surgery, Clínica Dr Duarte Miguel Ferreira Rodrigues Ribeiro, São Paulo, Brazil (D.M.F.R.R.); and Instituto de Radiologia-INRAD (A.H.M.C.) and Department of Gynecology (P.C.S.), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Angela H M Caiado
- From the Department of Diagnostic Imaging, Chamié Imagem da Mulher, Rua Casa do Ator, 1117, cj 72, São Paulo, SP 04546-004, Brazil (L.P.C.); Department of Diagnostic Imaging, Fleury Medicina e Saúde, São Paulo, Brazil (L.P.C., A.H.M.C., G.W.); Department of Female Reconstructive Surgery, Clínica Dr Duarte Miguel Ferreira Rodrigues Ribeiro, São Paulo, Brazil (D.M.F.R.R.); and Instituto de Radiologia-INRAD (A.H.M.C.) and Department of Gynecology (P.C.S.), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Gisele Warmbrand
- From the Department of Diagnostic Imaging, Chamié Imagem da Mulher, Rua Casa do Ator, 1117, cj 72, São Paulo, SP 04546-004, Brazil (L.P.C.); Department of Diagnostic Imaging, Fleury Medicina e Saúde, São Paulo, Brazil (L.P.C., A.H.M.C., G.W.); Department of Female Reconstructive Surgery, Clínica Dr Duarte Miguel Ferreira Rodrigues Ribeiro, São Paulo, Brazil (D.M.F.R.R.); and Instituto de Radiologia-INRAD (A.H.M.C.) and Department of Gynecology (P.C.S.), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Paulo C Serafini
- From the Department of Diagnostic Imaging, Chamié Imagem da Mulher, Rua Casa do Ator, 1117, cj 72, São Paulo, SP 04546-004, Brazil (L.P.C.); Department of Diagnostic Imaging, Fleury Medicina e Saúde, São Paulo, Brazil (L.P.C., A.H.M.C., G.W.); Department of Female Reconstructive Surgery, Clínica Dr Duarte Miguel Ferreira Rodrigues Ribeiro, São Paulo, Brazil (D.M.F.R.R.); and Instituto de Radiologia-INRAD (A.H.M.C.) and Department of Gynecology (P.C.S.), Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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Masteling M, Ashton-Miller JA, DeLancey JOL. Technique development and measurement of cross-sectional area of the pubovisceral muscle on MRI scans of living women. Int Urogynecol J 2018; 30:1305-1312. [PMID: 29974138 DOI: 10.1007/s00192-018-3704-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 06/18/2018] [Indexed: 12/28/2022]
Abstract
INTRODUCTION AND HYPOTHESIS Measurements of the anatomic cross-sectional area (CSA) of the pubovisceral muscle (PVM) in women are confounded by the difficulty of separating the muscle from the adjacent puborectal (PRM) and iliococcygeal (ICM) muscles when visualized in a plane orthogonal to the fiber direction. We tested the hypothesis that it might be possible to measure the PVM CSA within a defined region of interest based on magnetic resonance images (MRI). METHODS MRI scans of 11 women with unilateral PVM tears and seven primiparous women with intact muscles following elective C-section were used to identify the PVM injury zone defined by the mean location of its boundaries with the adjacent intact PRM and ICM from existing anatomic reference points using 3D Slicer and ImageJ software. Then, from the 15 or more 2-mm transverse slices available, the slice with the maximum anatomic CSA of the left and right PVM was found in 24 primiparous women with bilaterally intact muscles who had delivered via C-section. RESULTS Mean [± standard deviation (SD)] of the maximum left or right PVM cross-section areas for the 24 women, measured by two different raters, was 1.25 ± 0.29 cm2 (range 0.75-1.86). The 5th, 50th, and 95th percentile values were 0.77, 1.23, and 1.80 cm2, respectively. Inter- and intrarater measurement repeatability intraclass correlation coefficients exceeded 0.89 and 0.90, respectively. CONCLUSIONS It is possible to use MRI to identify the volume of interest with the maximum anatomic cross section of the PVM belly while minimizing the inadvertent inclusion of adjacent PRM or ICM in that measurement.
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Affiliation(s)
- Mariana Masteling
- Department of Mechanical Engineering, University of Michigan, 2350 Hayward St, Ann Arbor, MI, 48109, USA.
| | - James A Ashton-Miller
- Department of Mechanical Engineering, University of Michigan, 2350 Hayward St, Ann Arbor, MI, 48109, USA
| | - John O L DeLancey
- Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, 48109, USA
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Giraudet G, Patrouix L, Fontaine C, Demondion X, Cosson M, Rubod C. Three dimensional model of the female perineum and pelvic floor muscles. Eur J Obstet Gynecol Reprod Biol 2018; 226:1-6. [DOI: 10.1016/j.ejogrb.2018.05.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/01/2018] [Accepted: 05/10/2018] [Indexed: 11/26/2022]
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Predictive role of measurement of pelvic floor muscle thickness with static MRI in stress and mixed urinary incontinence. Int Urogynecol J 2018; 30:271-277. [DOI: 10.1007/s00192-018-3663-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 01/04/2018] [Indexed: 10/16/2022]
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Kobi M, Flusberg M, Paroder V, Chernyak V. Practical guide to dynamic pelvic floor MRI. J Magn Reson Imaging 2018; 47:1155-1170. [PMID: 29575371 DOI: 10.1002/jmri.25998] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 02/13/2018] [Indexed: 01/23/2023] Open
Abstract
Pelvic floor dysfunction encompasses a spectrum of functional disorders that result from impairment of the ligaments, fasciae, and muscles supporting the pelvic organs. It is a prevalent disorder that carries a lifetime risk over 10% for undergoing a surgical repair. Pelvic floor weakness presents as a wide range of symptoms, including pain, pelvic pressure or bulging, urinary and fecal incontinence, constipation, and sexual dysfunction. A correct diagnosis by clinical examination alone can be challenging, particularly in cases involving multiple compartments. Magnetic resonance imaging (MRI) allows noninvasive, radiation-free, high soft-tissue resolution evaluation of all three pelvic compartments, and has proved a reliable technique for accurate diagnosis of pelvic floor dysfunction. MR defecography with steady-state sequences allows detailed anatomic and functional evaluation of the pelvic floor. This article provides an overview of normal anatomy and function of the pelvic floor and discusses a practical approach to the evaluation of imaging findings of pelvic floor relaxation, pelvic organ prolapse, fecal incontinence, and obstructed defecation. LEVEL OF EVIDENCE 5 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1155-1170.
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Affiliation(s)
- Mariya Kobi
- Department of Radiology, Montefiore Medical Center, Bronx, New York, USA
| | - Milana Flusberg
- Department of Radiology, Montefiore Medical Center, Bronx, New York, USA
| | - Viktoriya Paroder
- Department of Radiology, Memorial Sloan Kettering Center, New York, New York, USA
| | - Victoria Chernyak
- Department of Radiology, Montefiore Medical Center, Bronx, New York, USA
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Khatri G, de Leon AD, Lockhart ME. MR Imaging of the Pelvic Floor. Magn Reson Imaging Clin N Am 2017; 25:457-480. [DOI: 10.1016/j.mric.2017.03.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Abdulaziz M, Deegan EG, Kavanagh A, Stothers L, Pugash D, Macnab A. Advances in basic science methodologies for clinical diagnosis in female stress urinary incontinence. Can Urol Assoc J 2017; 11:S117-S120. [PMID: 28616108 DOI: 10.5489/cuaj.4583] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We provide an overview of advanced imaging techniques currently being explored to gain greater understanding of the complexity of stress urinary incontinence (SUI) through better definition of structural anatomic data. Two methods of imaging and analysis are detailed for SUI with or without prolapse: 1) open magnetic resonance imaging (MRI) with or without the use of reference lines; and 2) 3D reconstruction of the pelvis using MRI. An additional innovative method of assessment includes the use of near infrared spectroscopy (NIRS), which uses non-invasive photonics in a vaginal speculum to objectively evaluate pelvic floor muscle (PFM) function as it relates to SUI pathology. Advantages and disadvantages of these techniques are described. The recent innovation of open-configuration magnetic resonance imaging (MRO) allows images to be captured in sitting and standing positions, which better simulates states that correlate with urinary leakage and can be further enhanced with 3D reconstruction. By detecting direct changes in oxygenated muscle tissue, the NIRS vaginal speculum is able to provide insight into how the oxidative capacity of the PFM influences SUI. The small number of units able to provide patient evaluation using these techniques and their cost and relative complexity are major considerations, but if such imaging can optimize diagnosis, treatment allocation, and selection for surgery enhanced imaging techniques may prove to be a worthwhile and cost-effective strategy for assessing and treating SUI.
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Affiliation(s)
- Marwa Abdulaziz
- PhD Candidate, Department of Experimental Medicine; University of British Columbia, Vancouver, BC, Canada
| | - Emily G Deegan
- Masters Candidate, Department of Experimental Medicine; University of British Columbia, Vancouver, BC, Canada
| | - Alex Kavanagh
- Department of Urologic Sciences; University of British Columbia, Vancouver, BC, Canada
| | - Lynn Stothers
- Department of Urologic Sciences; University of British Columbia, Vancouver, BC, Canada
| | - Denise Pugash
- Department of Radiology, BC Women's Hospital; University of British Columbia, Vancouver, BC, Canada
| | - Andrew Macnab
- Department of Urologic Sciences; University of British Columbia, Vancouver, BC, Canada
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Liu G, Cui Z, Dai Y, Yao Q, Xu J, Wu G. Paradoxical puborectalis syndrome on diffusion-weighted imaging: a retrospective study of 72 cases. Sci Rep 2017; 7:2925. [PMID: 28592800 PMCID: PMC5462772 DOI: 10.1038/s41598-017-03127-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 04/25/2017] [Indexed: 11/30/2022] Open
Abstract
This study aimed to evaluate the application value of diffusion-weighted imaging (DWI) for assessing paradoxical puborectalis syndrome (PPS) in patients with obstructive defecation syndrome (ODS). The medical records of 72 ODS patients who underwent magnetic resonance (MR)-DWI and MR-defecography were retrospectively reviewed. The differences in the apparent diffusion coefficients (ADCs) and the thickness of the right and left branches of the puborectalis muscles between the PPS(+) and PPS(−) groups were compared. In addition, the absolute within-patient differences between the right and left branches (ADC, thickness) were compared between the two groups. The absolute difference in ADCs (right branch - left branch) was significantly different between the two groups. Regardless of whether the ADC was acquired through single-ROI (0.10 ± 0.08 vs 0.23 ± 0.18, P = 0.000) or multi-ROI (0.16 ± 0.14 vs 0.27 ± 0.17, P = 0.009) analysis, the PPS(+) patients displayed a lower absolute ADC difference than did the PPS(−) patients. However, there was no statistically significant difference in the ADC value, thickness or the absolute difference in thickness between the two groups. These findings suggest that DWI may have value in quantitatively assessing the puborectalis muscle in ODS patients, whereas the value of puborectalis thickness in such aspect needs further study.
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Affiliation(s)
- Guiqin Liu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhe Cui
- Department of Gastrointestinal Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yongming Dai
- Magnetic Resonance Imaging Institute for Biomedical Research, Wayne State University, Detroit, MI, USA
| | - Qiuying Yao
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jianrong Xu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
| | - Guangyu Wu
- Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
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Pubovisceralis Muscle Fiber Architecture Determination: Comparison Between Biomechanical Modeling and Diffusion Tensor Imaging. Ann Biomed Eng 2017; 45:1255-1265. [DOI: 10.1007/s10439-016-1788-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 12/31/2016] [Indexed: 12/19/2022]
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Peng Y, Khavari R, Nakib NA, Boone TB, Zhang Y. Assessment of urethral support using MRI-derived computational modeling of the female pelvis. Int Urogynecol J 2016; 27:205-12. [PMID: 26224383 PMCID: PMC5519823 DOI: 10.1007/s00192-015-2804-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Accepted: 07/13/2015] [Indexed: 01/03/2023]
Abstract
INTRODUCTION AND HYPOTHESIS This study aimed to assess the role of individual anatomical structures and their combinations to urethral support function. METHODS A realistic pelvic model was developed from an asymptomatic female patient's magnetic resonance (MR) images for dynamic biomechanical analysis using the finite element method. Validation was performed by comparing simulation results with dynamic MR imaging observations. Weaknesses of anatomical support structures were simulated by reducing their material stiffness. Urethral mobility was quantified by examining urethral axis excursion from rest to the final state (intra-abdominal pressure = 100 cmH2O). Seven individual support structures and five of their combinations were studied. RESULT Among seven urethral support structures, we found that weakening the vaginal walls, puborectalis muscle, and pubococcygeus muscle generated the top three largest urethral excursion angles. A linear relationship was found between urethral axis excursions and intra-abdominal pressure. Weakening all three levator ani components together caused a larger weakening effect than the sum of each individually weakened component, indicating a nonlinearly additive pattern. The pelvic floor responded to different weakening conditions distinctly: weakening the vaginal wall developed urethral mobility through the collapsed vaginal canal, while weakening the levator ani showed a more uniform pelvic floor deformation. CONCLUSIONS The computational modeling and dynamic biomechanical analysis provides a powerful tool to better understand the dynamics of the female pelvis under pressure events. The vaginal walls, puborectalis, and pubococcygeus are the most important individual structures in providing urethral support. The levator ani muscle group provides urethral support in a well-coordinated way with a nonlinearly additive pattern.
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Affiliation(s)
- Yun Peng
- Department of Biomedical Engineering, Cullen College of Engineering, University of Houston, 2027 SERC Building, 3605 Cullen Blvd, Houston, TX, 77024, USA
| | - Rose Khavari
- Department of Urology, Houston Methodist Hospital and Research Institute, Houston, TX, 77030, USA
| | - Nissrine A Nakib
- Department of Urology, University of Minnesota, Minneapolis, MN, USA
| | - Timothy B Boone
- Department of Urology, Houston Methodist Hospital and Research Institute, Houston, TX, 77030, USA
| | - Yingchun Zhang
- Department of Biomedical Engineering, Cullen College of Engineering, University of Houston, 2027 SERC Building, 3605 Cullen Blvd, Houston, TX, 77024, USA.
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Javadian P, O'Leary D, Rostaminia G, North J, Wagner J, Quiroz LH, Shobeiri SA. How does 3D endovaginal ultrasound compare to magnetic resonance imaging in the evaluation of levator ani anatomy? Neurourol Urodyn 2015; 36:409-413. [PMID: 26669505 DOI: 10.1002/nau.22944] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 11/19/2015] [Indexed: 12/23/2022]
Abstract
INTRODUCTION AND HYPOTHESIS To compare magnetic resonance imaging (MRI) to 3D endovaginal ultrasound (EVUS) in the evaluation of major levator ani defects in women with pelvic floor disorders. METHODS A total of 21 subjects with pelvic floor with complaints of pelvic floor disorders were included in this study. EVUS imaging of the levator ani muscle (LAM) was performed in all subjects, and the LA muscle groups of interest evaluated were the puboanalis (PA), puborectalis (PR), and pubovisceralis (PV) muscles. The right and left subdivisions were evaluated separately, and classified as (i) normal, normal with only minor irregularities, grossly abnormal, or absent, or (ii) by the levator ani deficiency (LAD) score and classified by no defect (complete attachment of muscle to the pubic bone), <50% detachment or loss, >50% detachment or loss, and completely detached or complete muscle loss. Paired data were analyzed with McNemar's test or Bowker's test of symmetry. RESULTS When unilateral LAM subdivisions were classified as "normal," "normal with minor irregularity," "grossly abnormal," and "absent," there were no significant differences between MRI and EVUS by categorization of LAM defects. Comparing "normal" versus "abnormal," there was no difference between imaging modalities. When compared by LAD score evaluation, there were no differences in the categorization of unilateral defects between MRI and EVUS. CONCLUSIONS Endovaginal 3D US is comparable to MRI in its ability to identify both normal and abnormal LAM anatomy. Neurourol. Urodynam. 36:409-413, 2017. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Pouya Javadian
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Dena O'Leary
- Department of Obstetrics and Gynecology, Inova Fairfax Hospital, Fairfax, Virginia
| | - Ghazaleh Rostaminia
- Department of Obstetrics and Gynecology, Inova Fairfax Hospital, Fairfax, Virginia
| | - Justin North
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Jason Wagner
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - Lieschen H Quiroz
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
| | - S Abbas Shobeiri
- Department of Obstetrics and Gynecology, Inova Fairfax Hospital, Fairfax, Virginia
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An Anatomical and Functional Perspective of the Pelvic Floor and Urogenital Organ Support System. ACTA ACUST UNITED AC 2015. [DOI: 10.1097/jwh.0000000000000033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Akhondi-Asl A, Hoyte L, Lockhart ME, Warfield SK. A logarithmic opinion pool based STAPLE algorithm for the fusion of segmentations with associated reliability weights. IEEE TRANSACTIONS ON MEDICAL IMAGING 2014; 33:1997-2009. [PMID: 24951681 PMCID: PMC4264575 DOI: 10.1109/tmi.2014.2329603] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Pelvic floor dysfunction is common in women after childbirth and precise segmentation of magnetic resonance images (MRI) of the pelvic floor may facilitate diagnosis and treatment of patients. However, because of the complexity of its structures, manual segmentation of the pelvic floor is challenging and suffers from high inter and intra-rater variability of expert raters. Multiple template fusion algorithms are promising segmentation techniques for these types of applications, but they have been limited by imperfections in the alignment of templates to the target, and by template segmentation errors. A number of algorithms sought to improve segmentation performance by combining image intensities and template labels as two independent sources of information, carrying out fusion through local intensity weighted voting schemes. This class of approach is a form of linear opinion pooling, and achieves unsatisfactory performance for this application. We hypothesized that better decision fusion could be achieved by assessing the contribution of each template in comparison to a reference standard segmentation of the target image and developed a novel segmentation algorithm to enable automatic segmentation of MRI of the female pelvic floor. The algorithm achieves high performance by estimating and compensating for both imperfect registration of the templates to the target image and template segmentation inaccuracies. A local image similarity measure is used to infer a local reliability weight, which contributes to the fusion through a novel logarithmic opinion pooling. We evaluated our new algorithm in comparison to nine state-of-the-art segmentation methods and demonstrated our algorithm achieves the highest performance.
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Affiliation(s)
- Alireza Akhondi-Asl
- Computational Radiology Laboratory, Department of Radiology, Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
| | - Lennox Hoyte
- Department of Obstetrics and Gynecology, University of South Florida, 2 Tampa General Circle, 6th oor, Tampa, FL 33606, USA
| | - Mark E. Lockhart
- Department of Radiology, University of Alabama at Birmingham, 1802 6th Avenue South, Birmingham, AL 35233, USA
| | - Simon K. Warfield
- Computational Radiology Laboratory, Department of Radiology, Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, USA
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García del Salto L, de Miguel Criado J, Aguilera del Hoyo LF, Gutiérrez Velasco L, Fraga Rivas P, Manzano Paradela M, Díez Pérez de las Vacas MI, Marco Sanz AG, Fraile Moreno E. MR Imaging–based Assessment of the Female Pelvic Floor. Radiographics 2014; 34:1417-39. [DOI: 10.1148/rg.345140137] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Abstract
Physical examination alone is often inadequate for evaluation of pelvic floor dysfunction. Magnetic resonance imaging (MRI) is a robust modality that can provide high-quality anatomic and functional evaluation of the pelvic floor. Although lack of standardized technique and radiologist inexperience may be relative deterrents in universal acceptance of pelvic floor MRI, the role of MRI is increasing as it is technically feasible on most magnets and offers some advantages over the traditional fluoroscopic defecography. This review focuses on the technical and interpretational aspects of anatomic and functional pelvic floor MRI.
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Affiliation(s)
- Gaurav Khatri
- From the Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX
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Rostaminia G, White DE, Quiroz LH, Shobeiri SA. Levator plate descent correlates with levator ani muscle deficiency. Neurourol Urodyn 2013; 34:55-9. [DOI: 10.1002/nau.22509] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 09/04/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Ghazaleh Rostaminia
- Department of Obstetrics and Gynecology; The University of Oklahoma Health Sciences Center; Oklahoma City Oklahoma
| | - Dena E. White
- Department of Obstetrics and Gynecology; The University of Oklahoma Health Sciences Center; Oklahoma City Oklahoma
| | - Lieschen H. Quiroz
- Department of Obstetrics and Gynecology; The University of Oklahoma Health Sciences Center; Oklahoma City Oklahoma
| | - S. Abbas Shobeiri
- Department of Obstetrics and Gynecology; The University of Oklahoma Health Sciences Center; Oklahoma City Oklahoma
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Brandão S, Da Roza T, Parente M, Ramos I, Mascarenhas T, Natal Jorge RM. Magnetic resonance imaging of the pelvic floor: from clinical to biomechanical imaging. Proc Inst Mech Eng H 2013; 227:1324-32. [PMID: 24030164 DOI: 10.1177/0954411913502952] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This article reviews the current role of magnetic resonance imaging in the study of the pelvic floor anatomy and pelvic floor dysfunction. The application of static and dynamic magnetic resonance imaging in the clinical context and for biomechanical simulation modeling is assessed, and the main findings are summarized. Additionally, magnetic resonance-based diffusion tensor imaging is presented as a potential tool to evaluate muscle fiber morphology. In this article, focus is set on pelvic floor muscle damage related to urinary incontinence and pelvic organ prolapse, sometimes as a consequence of vaginal delivery. Modeling applications that evaluate anatomical and physiological properties of pelvic floor are presented to further illustrate their particular characteristics. Finally, finite element method is described as a method for modeling and analyzing pelvic floor structures' biomechanical performance, based on material and behavioral properties of the tissues, and considering pressure loads that mimic real-life conditions such as active contraction or Valsalva maneuver.
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Affiliation(s)
- Sofia Brandão
- Department of Radiology, Centro Hospitalar de São João-EPE, Porto, Portugal
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Shin DS, Jang HG, Hwang SB, Har DH, Moon YL, Chung MS. Two-dimensional sectioned images and three-dimensional surface models for learning the anatomy of the female pelvis. ANATOMICAL SCIENCES EDUCATION 2013; 6:316-323. [PMID: 23463707 DOI: 10.1002/ase.1342] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Revised: 11/20/2012] [Accepted: 11/27/2012] [Indexed: 06/01/2023]
Abstract
In the Visible Korean project, serially sectioned images of the pelvis were made from a female cadaver. Outlines of significant structures in the sectioned images were drawn and stacked to build surface models. To improve the accessibility and informational content of these data, a five-step process was designed and implemented. First, 154 pelvic structures were outlined with additional surface reconstruction to prepare the image data. Second, the sectioned and outlined images (in a browsing software) as well as the surface models (in a PDF file) were placed on the Visible Korean homepage in a readily-accessible format. Third, all image data were visualized with interactive elements to stimulate creative learning. Fourth, two-dimensional (2D) images and three-dimensional (3D) models were superimposed on one another to provide context and spatial information for students viewing these data. Fifth, images were designed such that structure names would be shown when the mouse pointer hovered over the 2D images or the 3D models. The state-of-the-art sectioned images, outlined images, and surface models, arranged and systematized as described in this study, will aid students in understanding the anatomy of female pelvis. The graphic data accompanied by corresponding magnetic resonance images and computed tomographs are expected to promote the production of 3D simulators for clinical practice.
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Affiliation(s)
- Dong Sun Shin
- Department of Anatomy, Ajou University School of Medicine, Suwon, Republic of Korea
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Assessment of levator ani morphology and function in asymptomatic nulliparous women via static and dynamic magnetic resonance imaging. Int J Gynaecol Obstet 2013; 121:233-9. [PMID: 23518136 DOI: 10.1016/j.ijgo.2013.01.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 01/15/2013] [Accepted: 02/21/2013] [Indexed: 11/21/2022]
Abstract
OBJECTIVE To evaluate levator ani morphology and function in healthy nulliparous women using static and dynamic magnetic resonance imaging. METHODS Eighty asymptomatic, healthy nulliparous Chinese women (mean age, 25.3±3.5years) volunteered for the present study. Static T2-weighted fast spin-echo images were employed to evaluate levator ani morphology; dynamic T2-weighted fast imaging employing steady-state acquisition was used to evaluate its function. A 2 samples t test was employed to compare groups. RESULTS No morphologic abnormality was detected in the 80 healthy nulliparous women. However, 15% (12/80) of women had various degrees of pelvic organ descent below the pubococcygeal line. In these women, the width of the pubic portion of the levator ani was significantly reduced during straining, whereas the levator plate angle, the levator hiatus area, and the H and M line lengths were enlarged. These changes were associated with weakened levator ani function and pelvic floor laxity. CONCLUSION Functional abnormality of the levator ani muscle was noted in nulliparous women at static and dynamic magnetic resonance imaging. Further follow-up investigation is needed to confirm whether women with functional abnormality are more likely to develop a prolapse after vaginal birth.
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Vergeldt TFM, Weemhoff M, Notten KJB, Kessels AGH, Kluivers KB. Comparison of two scoring systems for diagnosing levator ani muscle damage. Int Urogynecol J 2013; 24:1501-6. [DOI: 10.1007/s00192-013-2052-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 01/16/2013] [Indexed: 11/28/2022]
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Reference lines in dynamic magnetic resonance imaging of the pelvic floor. Female Pelvic Med Reconstr Surg 2012; 16:242-5. [PMID: 22453350 DOI: 10.1097/spv.0b013e3181ec2070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE : To compare the variability in two commonly used reference lines in pelvic magnetic resonance imaging (MRI), the pubococcygeal line (PCL) and the sacrococcygeal to inferior pubis (SCIPP) line, with respect to their distance from pelvic floor points of interest. METHODS : We obtained pelvic MR images of 20 asymptomatic nulliparous women who are part of an ongoing pelvic floor nerve injury postpartum study. The subjects underwent a high-resolution two-dimensional, T2-weighted sagittal pelvic MRI in the supine position using a GE Signa scanner with a body phased-array coil. We also obtained dynamic T2-weighted sagittal MR images in supine position during Kegel and Valsalva maneuvers. Using the midsagittal image, we measured the length of two reference lines: the PCL and the more cephalad SCIPP line. From each line, we then measured the perpendicular distance to the bladder neck and to the posterior margin of the anorectal angle (M-line). We compared the mean values of all measurements between the two reference lines with paired Student t tests. RESULT : The SCIPP line (mean [SD], 11.60 [0.91] cm) is longer than the PCL (mean [SD], 10.54 [0.85] cm) at rest (P < 0.001). There is no significant change in length from resting to Kegel maneuver or from resting to Valsalva maneuver in either reference line. Only the resting to Valsalva maneuver for the M-line was significantly different between the 2 reference lines (P = 0.02). The resting to Kegel for the perpendicular distance to the bladder neck and the M-line was not significantly different between the two lines. CONCLUSIONS : Both reference lines remain stable during pelvic floor maneuvers.
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Brown KM, Handa VL, Macura KJ, DeLeon VB. Three-dimensional shape differences in the bony pelvis of women with pelvic floor disorders. Int Urogynecol J 2012; 24:431-9. [DOI: 10.1007/s00192-012-1876-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Accepted: 06/23/2012] [Indexed: 10/28/2022]
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Rousset P, Delmas V, Buy JN, Rahmouni A, Vadrot D, Deux JF. In vivo visualization of the levator ani muscle subdivisions using MR fiber tractography with diffusion tensor imaging. J Anat 2012; 221:221-8. [PMID: 22757638 DOI: 10.1111/j.1469-7580.2012.01538.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Understanding the levator ani complex architecture is of major clinical relevance. The aim of this study was to determine the feasibility of magnetic resonance (MR) fiber tractography with diffusion tensor imaging (DTI) as a tool for the three-dimensional (3D) representation of normal subdivisions of the levator ani. Ten young nulliparous female volunteers underwent DTI at 1.5 T MR imaging. Diffusion-weighted axial sequence of the pelvic floor was performed with additional T2-weighted multiplanar sequences for anatomical reference. Fiber tractography for visualization of each Terminologia Anatomica-listed major levator ani subdivision was performed. Numeric muscular fibers extracted after tractography were judged as accurate when localized within the boundaries of the muscle, and inaccurate when projecting out of the boundaries of the muscle. From the fiber tracking of each subdivision the number of numeric fibers (inaccurate and accurate) and a score (from 3 to 0) of the adequacy of the 3D representation were calculated. All but two volunteers completed the protocol. The mean number of accurate fibers was 17 ± 2 for the pubovisceralis, 14 ± 6 for the puborectalis and 1 ± 1 for the iliococcygeus. The quality of the 3D representation was judged as good (score = 2) for the pubovisceralis and puborectalis, and inaccurate (score = 0) for the iliococcygeus. Our study is the first step to a 3D visualization of the three major levator ani subdivisions, which could help to better understand their in vivo functional anatomy.
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Affiliation(s)
- Pascal Rousset
- Radiology Department, Hôtel Dieu Hospital, University Paris Descartes, Assistance Publique-Hôpitaux de Paris, Paris, France.
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Rodrigues AA, Bassaly R, McCullough M, Terwilliger HL, Hart S, Downes K, Hoyte L. Levator ani subtended volume: a novel parameter to evaluate levator ani muscle laxity in pelvic organ prolapse. Am J Obstet Gynecol 2012; 206:244.e1-9. [PMID: 22075059 DOI: 10.1016/j.ajog.2011.10.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2011] [Revised: 08/18/2011] [Accepted: 10/03/2011] [Indexed: 10/16/2022]
Abstract
OBJECTIVE We describe a new parameter based on magnetic resonance 3-dimensional (3D) reconstructions proposed to evaluate levator ani muscle (LAM) laxity in women with pelvic organ prolapse (POP). STUDY DESIGN This is an institutional review board-approved, retrospective chart review of 35 women with POP, stages I-IV. The 3D Slicer software package was used to perform 2-dimensional and 3D measurements and the levator ani subtended volume (LASV) was described. Basically, the LASV represents the volume contained by LAM between 2 planes, which coincides with pubococcygeal line and H line. Correlations among measurements, ordinal POP stages, POP Quantification (POPQ) individual measurements, and validated questionnaires were performed. RESULTS The LASV differentiated major (III and IV) from minor (I and II) POPQ stages, which positively correlated to POP stages and POPQ individual measurements. CONCLUSION The LASV is a promising parameter to evaluate the LAM laxity.
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Loubeyre P, Copercini M, Petignat P, Dubuisson JB. Levator Ani Muscle Complex: Anatomic Findings in Nulliparous Patients at Thin-Section MR Imaging with Double Opacification. Radiology 2012; 262:538-43. [DOI: 10.1148/radiol.11111014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wu R, Hu B, Ma F, Kuang SL, Huang Y, Li Q, Yao MH. A comparative study of the sonographic appearance and anatomy of the obturator internus in normal males. MINIM INVASIV THER 2011; 21:271-5. [PMID: 22066861 DOI: 10.3109/13645706.2011.602691] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The aim of this study was to compare the appearance of the normal male obturator internus on transrectal ultrasound with anatomical examination to advance the knowledge of the male pelvic muscles. This information may help to provide a new imaging method for observation of the normal male obturator internus and may facilitate the treatment of obturator internus abscesses and various other types of interventional therapies. Ten formalin-fixed male cadavers were dissected to examine the appearance and structure of the obturator internus and its relationship with the structures in close proximity. The obturator internus was also observed in five fresh male cadavers using transrectal ultrasound, after which the anatomy of the muscle was confirmed by dissection and its thickness measured. The visible fusiform was observed by sonography. The measurements of obturator internus thickness were 13.33 ± 0.32 mm on the right and 13.41 ± 0.26 mm on the left; in the formalin-fixed fresh cadaver, the measurements were 13.16 ± 0.21 mm on the right and 13.17 ± 0.22 mm on the left. Using transrectal ultrasound to recognize and observe the obturator internus is a new imaging method that will provide a foundation for the recognition of its abnormalities in the future.
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Affiliation(s)
- Rong Wu
- Department of Ultrasound in Medicine, Shanghai tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
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Hoyte L, Ye W, Brubaker L, Fielding JR, Lockhart ME, Heilbrun ME, Brown MB, Warfield SK. Segmentations of MRI images of the female pelvic floor: a study of inter- and intra-reader reliability. J Magn Reson Imaging 2011; 33:684-91. [PMID: 21563253 DOI: 10.1002/jmri.22478] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To describe the inter- and intra-operator reliability of segmentations of female pelvic floor structures. MATERIALS AND METHODS Three segmentation specialists were asked to segment out the female pelvic structures in 20 MR datasets on three separate occasions. The STAPLE algorithm was used to compute inter- and intra-segmenter agreement of each organ in each dataset. STAPLE computed the sensitivity, specificity, and positive predictive values (PPV) for inter- and intra-segmenter repeatability. These parameters were analyzed using intra-class correlation analysis. Correlation of organ volume to PPV and sensitivity was also computed. RESULTS Mean PPV of the segmented organs ranged from 0.82 to 0.99, and sensitivity ranged from 33 to 96%. Intra-class correlation ranged from 0.07 to 0.98 across segmenters. Pearson correlation of volume to sensitivity were significant across organs, ranging from 0.54 to 0.91. Organs with significant correlation of PPV to volume were bladder (-0.69), levator ani (-0.68), and coccyx (-0.63). CONCLUSION Undirected manual segmentation of the pelvic floor organs are adequate for locating the organs, but poor at defining structural boundaries.
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Affiliation(s)
- Lennox Hoyte
- University of South Florida, College of Medicine, Division of Urogynecology and Pelvic Reconstructive Surgery, Tampa General Hospital, Urogynecology Division, Tampa, Florida, USA.
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Alterations in pelvic floor muscles and pelvic organ support by pregnancy and vaginal delivery in squirrel monkeys. Int Urogynecol J 2011; 22:1109-16. [PMID: 21567260 DOI: 10.1007/s00192-011-1443-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 04/19/2011] [Indexed: 12/27/2022]
Abstract
INTRODUCTION AND HYPOTHESIS The objective of this study was to measure the effects of pregnancy and parturition on pelvic floor muscles and pelvic organ support. METHODS Levator ani, obturator internus, and coccygeus (COC) muscle volumes and contrast uptake were assessed by MRI of seven females prior to pregnancy, 3 days, and 4 months postpartum. Bladder neck and cervix position were measured dynamically with abdominal squeezing. RESULTS The sides of three paired muscles were similar (p > 0.66). COC volumes were greater (p < 0.004) after parturition than before pregnancy or after recovery. COC contrast uptake increased (p < 0.02) immediately after delivery. Bladder neck position both in the relaxed state and abdominal pressure descended (p < 0.04) after delivery and descended further (p < 0.001) after recovery. Cervical position in the relaxed state before delivery was higher (p < 0.001) than postpartum but was unchanged (p = 0.50) with abdominal pressure relative to delivery. CONCLUSION In squirrel monkeys, coccygeus muscles demonstrate the greatest change related to parturition, and parturition-related bladder neck descent seems permanent.
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Blasi I, Fuchs I, D'Amico R, Vinci V, La Sala GB, Mazza V, Henrich W. Intrapartum translabial three-dimensional ultrasound visualization of levator trauma. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2011; 37:88-92. [PMID: 20814872 DOI: 10.1002/uog.8818] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
OBJECTIVES The aim of this study was to visualize levator trauma by three-dimensional (3D) ultrasound performed during labor and soon after the crowning of the fetal head and to determine how often levator trauma occurs. METHODS This was a prospective, observational study of 66 women enrolled during the first stage of labor. The women underwent intrapartum 3D transperineal ultrasound examination during the first and second stages of labor and within 12 h after delivery. Volume datasets were acquired and analyzed to determine the presence of levator trauma. RESULTS Data from 10 of the 66 women were excluded from analysis-nine because they underwent Cesarean section in the first or second stage of labor and one because she underwent hysterectomy and no postpartum volumes were collected. Thus our study group comprised 56 women-35 nulliparous and 21 parous. A total of 504 volumes were collected in the 56 women (three volumes for each stage of labor). One hundred and twenty levator volumes were excluded from analysis, but volumes of acceptable quality were available for all three stages of labor in all women. Eleven (31.4%) of the 35 nulliparae had levator lesions detected postpartum and none of them had levator lesions before delivery. Five (23.8%) of the 21 parous women had a levator tear detected in their postpartum volumes. In two of these five women the levator tear was also present in both volumes taken during labor. CONCLUSIONS Visualization of the levator ani during labor by 3D ultrasound examination is feasible. Comparison of volumes obtained during labor and within the first 2 h after delivery supports the theory that crowning of the head is the immediate cause of avulsion of the levator ani muscle.
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Affiliation(s)
- I Blasi
- Department of Obstetrics and Gynaecology, Modena and Reggio Emilia University, Reggio Emilia, Italy.
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Li X, Kruger JA, Nash MP, Nielsen PMF. Modeling childbirth: elucidating the mechanisms of labor. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2010; 2:460-470. [PMID: 20836041 DOI: 10.1002/wsbm.65] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The process of childbirth and the mechanisms of labor have been studied for over a century, beginning with simple measurements of fetal skull and maternal pelvis dimensions. More recently, X-rays, ultrasound, and magnetic resonance imaging have been used to try and quantify the biomechanics of labor. With the development of computational technologies, biomechanical models have emerged as a quantitative analysis tool for modeling childbirth. These methods are well known for their capabilities to analyze function at the organ scale. This review provides an overview of the state-of-the-art finite element models of the mechanics of vaginal delivery, with detailed descriptions of the data sources, modeling frameworks, and results. We also discuss the limitations and improvements required in order for the models to be more accurate and clinically useful. Some of the major challenges include: modeling the complex geometry of the maternal pelvic floor muscles and fetal head motion during the second stage of labor; the lack of experimental data on the pelvic floor structures; and development of methods for clinical validation. To date, models have had limited success in helping clinicians understand possible factors leading to birth-induced pelvic floor muscle injuries and dysfunction. However, much more can be achieved with further development of these quantitative modeling frameworks, such as tools for birth planning and medical education.
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Affiliation(s)
- Xinshan Li
- Auckland Bioengineering Institute, The University of Auckland, New Zealand
| | - Jennifer A Kruger
- Department of Sport and Exercise Science, The University of Auckland, New Zealand
| | - Martyn P Nash
- Auckland Bioengineering Institute, The University of Auckland, New Zealand
| | - Poul M F Nielsen
- Auckland Bioengineering Institute, The University of Auckland, New Zealand
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