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Journal of Gynecologic Oncology Nov 2017To compare the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) for detecting myometrial infiltration (MI) in endometrial... (Comparative Study)
Comparative Study Meta-Analysis Review
Transvaginal ultrasound versus magnetic resonance imaging for preoperative assessment of myometrial infiltration in patients with endometrial cancer: a systematic review and meta-analysis.
OBJECTIVE
To compare the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) for detecting myometrial infiltration (MI) in endometrial carcinoma.
METHODS
An extensive search of papers comparing TVS and MRI in assessing MI in endometrial cancer was performed in MEDLINE (PubMed), Web of Science, and Cochrane Database from January 1989 to January 2017. Quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool.
RESULTS
Our extended search identified 747 citations but after exclusions we finally included in the meta-analysis 8 articles. The risk of bias for most studies was low for most 4 domains assessed in QUADAS-2. Overall, pooled estimated sensitivity and specificity for diagnosing deep MI were 75% (95% confidence interval [CI]=67%-82%) and 82% (95% CI=75%-93%) for TVS, and 83% (95% CI=76%-89%) and 82% (95% CI=72%-89%) for MRI, respectively. No statistical differences were found when comparing both methods (p=0.314). Heterogeneity was low for sensitivity and high for specificity for TVS and MRI.
CONCLUSION
MRI showed a better sensitivity than TVS for detecting deep MI in women with endometrial cancer. However, the difference observed was not statistically significant.
Topics: Endometrial Neoplasms; Female; Humans; Magnetic Resonance Imaging; Myometrium; Neoplasm Invasiveness; Preoperative Care; Sensitivity and Specificity; Ultrasonography; Vagina
PubMed: 29027404
DOI: 10.3802/jgo.2017.28.e86 -
Acta Obstetricia Et Gynecologica... Jan 2018Our objective was to elucidate the overall diagnostic accuracy of ultrasound in detecting the severity of abnormally invasive placentation (AIP). (Review)
Review
INTRODUCTION
Our objective was to elucidate the overall diagnostic accuracy of ultrasound in detecting the severity of abnormally invasive placentation (AIP).
MATERIAL AND METHODS
Medline, Embase, CINAHL and The Cochrane databases were searched. The ultrasound signs explored were: loss of hypoechoic (clear) zone in the placental-uterine interface, placental lacunae, bladder wall interruption, myometrial thinning, focal exophitic mass, placental lacunar flow, subplacental vascularity, and uterovesical hypervascularity.
RESULTS
Twenty studies (3209 pregnancies) were included. Ultrasound had an overall good diagnostic accuracy in identifying the depth of placental invasion with sensitivities of 90.6%, 93.0%, 89.5%, and 81.2% for placenta accreta, increta, accreta/increta, and percreta, respectively; the corresponding specificities were 97.1%, 98.4%, 94.7%, and 98.9%. Placental lacunae had sensitivities of 74.8%, 88.6%, and 76.3% for the detection of placenta accreta, increta, and percreta, respectively. Sensitivity and specificity of loss of the clear zone in identifying placenta accreta were 74.9% and 92.0%, whereas the corresponding figures for placenta increta and percreta were 91.6% and 76.9%, and 88.1% and 71.1%. Lacunar flow had sensitivities of 81.2%, 84.3%, and 45.2% for the detection of placenta accreta, increta, and percreta respectively; the corresponding figures for specificity were 84.0%, 79.7%, and 75.3%. Sensitivity of uterovesical hypervascularity was low for the detection of placenta accreta (12.3%) but high for placenta increta (94.4%) and percreta (86.2%); the corresponding figures for specificity were 90.8%, 88.0% and 88.2%, respectively.
CONCLUSIONS
Ultrasound has an overall good diagnostic accuracy in recognizing the depth and the topography of placental invasion.
Topics: Female; Humans; Myometrium; Placenta; Placenta Accreta; Pregnancy; Sensitivity and Specificity; Ultrasonography, Prenatal
PubMed: 28963728
DOI: 10.1111/aogs.13238 -
Ultrasound in Obstetrics & Gynecology :... Feb 2018The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester of pregnancy. Secondary aims were to ascertain the strength of association and the predictive accuracy of such signs in detecting AIP in the first trimester.
METHODS
An electronic search of MEDLINE, EMBASE, CINAHL and Cochrane databases (2000-2016) was performed. Only studies reporting on first-trimester diagnosis of AIP that was subsequently confirmed in the third trimester either during operative delivery or by pathological examination were included. Meta-analysis of proportions, random-effects meta-analysis and hierarchical summary receiver-operating characteristics curve analysis were used to analyze the data.
RESULTS
Seven studies, involving 551 pregnancies at high risk of AIP, were included. At least one ultrasound sign suggestive of AIP was detected in 91.4% (95% CI, 85.8-95.7%) of cases with confirmed AIP. The most common ultrasound feature in the first trimester of pregnancy was low implantation of the gestational sac close to a previous uterine scar, which was observed in 82.4% (95% CI, 46.6-99.8%) of cases. Anechoic spaces within the placental mass (lacunae) were observed in 46.0% (95% CI, 10.9-83.7%) and a reduced myometrial thickness in 66.8% (95% CI, 45.2-85.2%) of cases affected by AIP. Pregnancies with a low implantation of the gestational sac had a significantly higher risk of AIP (odds ratio, 19.6 (95% CI, 6.7-57.3)), with a sensitivity and specificity of 44.4% (95% CI, 21.5-69.2%) and 93.4% (95% CI, 90.5-95.7%), respectively.
CONCLUSIONS
Ultrasound signs of AIP can be present during the first trimester of pregnancy, even before 11 weeks' gestation. Low anterior implantation of the placenta/gestational sac close to or within the scar was the most commonly seen early ultrasound sign suggestive of AIP, although its individual predictive accuracy was not high. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Female; Humans; Myometrium; Placenta; Placenta Accreta; Pregnancy; Pregnancy Trimester, First; Sensitivity and Specificity; Ultrasonography, Prenatal
PubMed: 28833750
DOI: 10.1002/uog.18840 -
The Cochrane Database of Systematic... May 2017Focal abnormalities most commonly acquired within the uterine cavity include endometrial polyps (arising from the endometrium) and submucous fibroids (arising from the... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Focal abnormalities most commonly acquired within the uterine cavity include endometrial polyps (arising from the endometrium) and submucous fibroids (arising from the myometrium). These benign abnormalities can cause several problems, including abnormal uterine bleeding (AUB) and subfertility. Two-dimensional saline infusion sonography (2D SIS) is a minimally invasive test that can be used to diagnose these pathologies, but it is less accurate than hysteroscopy, which is a more invasive procedure by which an endoscope allows direct visualisation of the uterine cavity. Three-dimensional (3D) SIS appears to enhance sonographic visualisation within the uterine cavity, thereby offering a potentially more accurate minimally invasive diagnostic test.
OBJECTIVES
Primary objectives • To evaluate the diagnostic accuracy of 3D SIS (index test 1) compared with 2D SIS for the diagnosis of focally growing lesions (presence or not) in women with AUB or subfertility, with hysteroscopy performed as the reference test. • To evaluate the diagnostic accuracy of 2D+3D SIS (index test 2) compared with 2D SIS for the diagnosis of focally growing lesions (presence or not) in women with AUB or subfertility, with hysteroscopy performed as the reference test. In this case, any abnormality on either modality was regarded as a positive result ('OR' approach). Secondary objectives • To evaluate the diagnostic accuracy of 3D SIS (index test 1) compared with 2D SIS according to type of abnormality and discrimination between uterine polyps and submucous fibroids in women with AUB or subfertility, with hysteroscopy and histology used as the reference.• To evaluate the diagnostic accuracy of 2D+3D SIS (index test 2) compared with 2D SIS according to type of abnormality and discrimination between uterine polyps and submucous fibroids in women with AUB or subfertility, with hysteroscopy and histology used as the reference.
SEARCH METHODS
We searched the following databases: Cochrane Central Register of Studies Online (CENTRAL CRSO), MEDLINE, Embase, PubMed, Cochrane Gynaecology and Fertility Group (CGF) Specialised Register and CGFG Diagnostic Test Accuracy (DTA) Specialised Register, clinicaltrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). Screening reference lists of appropriate studies was also performed. We screened for eligibility all studies identified from inception until March 2016. We performed searches with no date or language restrictions.
SELECTION CRITERIA
The population of interest consisted of premenopausal women with AUB or subfertility and postmenopausal women with AUB. Diagnostic test accuracy studies, randomised controlled trials (RCTs) and prospective cohort studies were eligible for inclusion if they evaluated the accuracy of both 2D SIS and 3D SIS for the diagnosis of acquired intracavitary abnormalities with hysteroscopy used as the reference standard. In light of the lack of data for 3D SIS, we also included studies that evaluated the accuracy of 3D SIS alone.
DATA COLLECTION AND ANALYSIS
Two review authors read all potentially eligible references after performing a first screening by title and abstract (LLN and FJRH). They independently extracted data to construct 2×2 tables from eligible studies and assessed studies for methodological quality using the QUADAS-2 tool (revised tool for quality assessment of diagnostic accuracy studies). To describe and visually present results, we produced in RevMan forest plots showing pairs of sensitivity and specificity together with 95% confidence intervals from each study, as well as raw receiver operating characteristic (ROC) plots. We displayed paired analyses in an ROC plot by linking sensitivity-specificity pairs from each study by using a dashed line. To compare 3D SIS versus 2D SIS, we restricted analyses to studies that provided 2×2 tables for both tests and used the bivariate meta-analysis of sensitivity and specificity.
MAIN RESULTS
Thirteen studies (1053 women) reported the accuracy of 3D SIS for focal uterine abnormalities; 11 of these (846 women) were suitable for meta-analysis, and eight reported accuracy according to the type of focal abnormality. The design of the included studies seems applicable. The main problem involving the quality of included studies is insufficient reporting of study methods, resulting in unclear risk of bias for several of the quality domains assessed. Therefore, we considered the overall quality of the evidence as low. The summary estimate (11 studies reporting absence or presence of abnormality at 3D SIS) for sensitivity was 94.5% (95% confidence interval (CI) 90.6% to 96.9%) and for specificity 99.4% (95% CI 96.2% to 99.9%). Meta-analysis of the eight studies (N = 716) directly comparing 2D SIS versus 3D SIS showed summary sensitivity of 96.9% (95% CI 91.9% to 98.8%) and summary specificity of 99.5% (95% CI 96.1% to 100%) for 3D SIS. For 2D SIS, summary sensitivity was 90.9% (95% CI 81.2% to 95.8%) and summary specificity was 96.3% (95% CI 86.1% to 99.1%). The difference in accuracy between 2D SIS and 3D SIS was non-significant (P values of 0.07 for sensitivity and 0.10 for specificity).
AUTHORS' CONCLUSIONS
Low-quality evidence suggests that 3D SIS may be very accurate in detecting intracavitary abnormalities. Meta-analysis revealed no statistically significant differences between 2D SIS and 3D SIS. Summary sensitivity and summary specificity are higher for 3D SIS, but margins of improvement are limited because 2D SIS is already very accurate. When the technology and appropriate expertise are available, 3D SIS offers an alternative to 2D SIS. Both 2D SIS and 3D SIS should be considered alternatives to diagnostic hysteroscopy when intracavitary pathology is suspected in subfertile women and in those with abnormal uterine bleeding.
Topics: Endometrium; Female; Humans; Hysteroscopy; Leiomyoma; Observational Studies as Topic; Polyps; Prospective Studies; ROC Curve; Randomized Controlled Trials as Topic; Reference Standards; Sensitivity and Specificity; Sodium Chloride; Solutions; Ultrasonography, Interventional; Uterine Diseases; Uterine Hemorrhage
PubMed: 28472862
DOI: 10.1002/14651858.CD011126.pub2 -
Ultrasound in Obstetrics & Gynecology :... Nov 2017There is a growing body of evidence that suggests that the surgical technique for uterine closure following Cesarean delivery influences the healing of the Cesarean... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
There is a growing body of evidence that suggests that the surgical technique for uterine closure following Cesarean delivery influences the healing of the Cesarean scar, but there is still no consensus on the optimal technique. The aim of this systematic review and meta-analysis was to compare the effect of single- vs double-layer uterine closure on the risk of uterine scar defect.
METHODS
MEDLINE, Scopus, ClinicalTrials.gov, PROSPERO, EMBASE and the Cochrane Central Register of Controlled Trials were searched from inception of each database until May 2016. All randomized controlled trials (RCTs) evaluating the effect of single- vs double-layer uterine closure following low transverse Cesarean section on the risk of uterine scar defect were included. The primary outcome was the incidence of uterine scar defects detected on ultrasound. Secondary outcomes were residual myometrial thickness evaluated by ultrasound and the incidence of uterine dehiscence and/or rupture in subsequent pregnancy. Summary measures were reported as relative risk (RR) or mean difference (MD), with 95% CIs. Quality of the evidence was assessed using the GRADE approach.
RESULTS
Nine RCTs (3969 participants) were included in the meta-analysis. The overall risk of bias of the included trials was low. Statistical heterogeneity within the studies was low, with no inconsistency in the primary and secondary outcomes. Women who received single-layer uterine closure had a similar incidence of uterine scar defects as did women who received double-layer closure (25% vs 43%; RR, 0.77 (95% CI, 0.36-1.64); five trials; 350 participants; low quality of evidence). Compared with double-layer uterine closure, women who received single-layer closure had a significantly thinner residual myometrium on ultrasound (MD, -2.19 mm (95% CI, -2.80 to -1.57 mm); four trials; 374 participants; low quality of evidence). No difference was found in the incidence of uterine dehiscence (0.4% vs 0.2%; RR, 1.34 (95% CI, 0.24-4.82); three trials; 3421 participants; low quality of evidence) or uterine rupture (0.1% vs 0.1%; RR, 0.52 (95% CI, 0.05-5.53); one trial; 3234 participants; low quality of evidence) in a subsequent pregnancy.
CONCLUSIONS
Single- and double-layer closure of the uterine incision following Cesarean delivery are associated with a similar incidence of Cesarean scar defects, as well as uterine dehiscence and rupture in a subsequent pregnancy. However, the quality level of summary estimates, as assessed by GRADE, was low, indicating that the true effect may be, or is even likely to be, substantially different from the estimate of the effect. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
Topics: Cesarean Section; Cicatrix; Female; Humans; Myometrium; Postoperative Complications; Pregnancy; Randomized Controlled Trials as Topic; Risk Factors; Surgical Wound Dehiscence; Suture Techniques; Uterine Rupture; Uterus
PubMed: 28070914
DOI: 10.1002/uog.17401 -
BMC Medical Genomics Jun 2015Preterm birth (PTB), or birth before 37 weeks of gestation, is the leading cause of newborn death worldwide. PTB is a critical area of scientific study not only due to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Preterm birth (PTB), or birth before 37 weeks of gestation, is the leading cause of newborn death worldwide. PTB is a critical area of scientific study not only due to its worldwide toll on human lives and economies, but also due to our limited understanding of its pathogenesis and, therefore, its prevention. This systematic review and meta-analysis synthesizes the landscape of PTB transcriptomics research to further our understanding of the genes and pathways involved in PTB subtypes.
METHODS
We evaluated published genome-wide pregnancy studies across gestational tissues and pathologies, including those that focus on PTB, by performing a targeted PubMed MeSH search and systematically reviewing all relevant studies.
RESULTS
Our search yielded 2,361 studies on gestational tissues including placenta, decidua, myometrium, maternal blood, cervix, fetal membranes (chorion and amnion), umbilical cord, fetal blood, and basal plate. Selecting only those original research studies that measured transcription on a genome-wide scale and reported lists of expressed genetic elements identified 93 gene expression, 21 microRNA, and 20 methylation studies. Although 30 % of all PTB cases are due to medical indications, 76 % of the preterm studies focused on them. In contrast, only 18 % of the preterm studies focused on spontaneous onset of labor, which is responsible for 45 % of all PTB cases. Furthermore, only 23 of the 10,993 unique genetic elements reported to be transcriptionally active were recovered 10 or more times in these 134 studies. Meta-analysis of the 93 gene expression studies across 9 distinct gestational tissues and 29 clinical phenotypes showed limited overlap of genes identified as differentially expressed across studies.
CONCLUSIONS
Overall, profiles of differentially expressed genes were highly heterogeneous both between as well as within clinical subtypes and tissues as well as between studies of the same clinical subtype and tissue. These results suggest that large gaps still exist in the transcriptomic study of specific clinical subtypes as well in the generation of the transcriptional profile of well-studied clinical subtypes; understanding the complex landscape of prematurity will require large-scale, systematic genome-wide analyses of human gestational tissues on both understudied and well-studied subtypes alike.
Topics: DNA Methylation; Female; Gene Expression Profiling; Gene Expression Regulation, Developmental; Genome-Wide Association Study; Humans; Phenotype; Placenta; Pregnancy; Premature Birth; Risk Factors; Term Birth; Transcriptome
PubMed: 26044726
DOI: 10.1186/s12920-015-0099-8 -
Ultrasound in Obstetrics & Gynecology :... Oct 2015To review the diagnostic accuracy of transvaginal ultrasound (TVS) in the preoperative detection of deep myometrial infiltration in patients with endometrial cancer,... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To review the diagnostic accuracy of transvaginal ultrasound (TVS) in the preoperative detection of deep myometrial infiltration in patients with endometrial cancer, comparing subjective and objective methods.
METHODS
An extensive search was performed in MEDLINE (PubMed) and EMBASE for studies published between January 1989 and December 2014. The eligibility criterion was use of TVS for preoperative assessment of myometrial infiltration by subjective evaluation and/or objective measurements. Objective measurements included, specifically, the approaches of Gordon (ratio of the distance between endometrium-myometrium interface and maximum tumor depth to the total myometrial thickness) and Karlsson (endometrial tumor thickness/anteroposterior uterine diameter ratio), in women with endometrial cancer, using the surgical pathological data as a reference standard. Study quality was assessed using the QUADAS-2 tool.
RESULTS
Our extended search identified a total of 184 citations, among which we examined the full text of 24 articles. Overall pooled sensitivity, specificity, positive likelihood ratio (LR+) and negative likelihood ratio (LR-) of TVS for detecting deep myometrial infiltration were 82% (95% CI, 76-87%), 81% (95% CI, 76-85%), 4.3 (95% CI, 3.6-5.3) and 0.22 (95% CI, 0.16-0.30), respectively. We did not observe differences among the three methods in terms of diagnostic performance. Significant heterogeneity was found for sensitivity and specificity of all three methods (I(2) range, 60.6-95.0). The main limitation was that very few studies compared different approaches in the same set of patients.
CONCLUSION
Diagnostic performance of TVS for detecting deep myometrial infiltration in women with endometrial cancer is moderate.
Topics: Endometrial Neoplasms; Endosonography; Female; Humans; Myometrium; Neoplasm Invasiveness; Preoperative Care; Prospective Studies; Sensitivity and Specificity; Vagina
PubMed: 26011665
DOI: 10.1002/uog.14905 -
Cancer Imaging : the Official... Nov 2014The objective of this study was to perform a systematic review and a meta-analysis in order to estimate the diagnostic accuracy of diffusion weighted imaging (DWI) in... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The objective of this study was to perform a systematic review and a meta-analysis in order to estimate the diagnostic accuracy of diffusion weighted imaging (DWI) in the preoperative assessment of deep myometrial invasion in patients with endometrial carcinoma.
METHODS
Studies evaluating DWI for the detection of deep myometrial invasion in patients with endometrial carcinoma were systematically searched for in the MEDLINE, EMBASE, and Cochrane Library from January 1995 to January 2014. Methodologic quality was assessed by using the Quality Assessment of Diagnostic Accuracy Studies tool. Bivariate random-effects meta-analytic methods were used to obtain pooled estimates of sensitivity, specificity, diagnostic odds ratio (DOR) and receiver operating characteristic (ROC) curves. The study also evaluated the clinical utility of DWI in preoperative assessment of deep myometrial invasion.
RESULTS
Seven studies enrolling a total of 320 individuals met the study inclusion criteria. The summary area under the ROC curve was 0.91. There was no evidence of publication bias (P = 0.90, bias coefficient analysis). Sensitivity and specificity of DWI for detection of deep myometrial invasion across all studies were 0.90 and 0.89, respectively. Positive and negative likelihood ratios with DWI were 8 and 0.11 respectively. In patients with high pre-test probabilities, DWI enabled confirmation of deep myometrial invasion; in patients with low pre-test probabilities, DWI enabled exclusion of deep myometrial invasion. The worst case scenario (pre-test probability, 50%) post-test probabilities were 89% and 10% for positive and negative DWI results, respectively.
CONCLUSION
DWI has high sensitivity and specificity for detecting deep myometrial invasion and more importantly can reliably rule out deep myometrial invasion. Therefore, it would be worthwhile to add a DWI sequence to the standard MRI protocols in preoperative evaluation of endometrial cancer in order to detect deep myometrial invasion, which along with other poor prognostic factors like age, tumor grade, and LVSI would be useful in stratifying high risk groups thereby helping in the tailoring of surgical approach in patient with low risk of endometrial carcinoma.
Topics: Diffusion Magnetic Resonance Imaging; Endometrial Neoplasms; Female; Humans; Myometrium; Neoplasm Invasiveness; Preoperative Care; Publication Bias; ROC Curve
PubMed: 25608571
DOI: 10.1186/s40644-014-0032-y -
Ultrasound in Obstetrics & Gynecology :... Jul 2014To assess systematically the performance of prenatal magnetic resonance imaging (MRI) in diagnosing the presence, degree and topography of disorders of invasive... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To assess systematically the performance of prenatal magnetic resonance imaging (MRI) in diagnosing the presence, degree and topography of disorders of invasive placentation and to explore the role of the different MRI signs in predicting these disorders. The diagnostic accuracy of ultrasound and MRI in the detection of invasive placentation was also compared.
METHODS
MEDLINE, EMBASE, CINAHL and The Cochrane Library, including The Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and The Cochrane Central Register of Controlled Trials, were searched electronically utilizing combinations of the relevant medical subject heading terms, keywords and word variants for 'invasive placentation' and 'magnetic resonance imaging'. Only prospective studies reporting a diagnosis of invasive placentation at the time of MRI and retrospective studies in which the radiologist was blinded to the final results were included in the analysis. The MRI signs explored were: uterine bulging, heterogeneous signal intensity, dark intraplacental bands on T2 weighted sequences, focal interruption of the myometrium and tenting of the bladder. Summary estimates of sensitivity, specificity, positive and negative likelihood ratios (LR+, LR-) and diagnostic odds ratio (DOR) were based, depending on the number of studies, upon DerSimonian-Laird random-effect or hierarchical summary receiver-operating characteristics models.
RESULTS
A total of 18 studies involving 1010 pregnancies at risk for invasive placentation were included. The overall diagnostic accuracy of MRI in detecting the presence of invasive placentation was: sensitivity, 94.4% (95% CI, 86.0-97.9%); specificity, 84.0% (95% CI, 76.0-89.8%); LR+, 5.91 (95% CI, 3.73-9.39); LR-, 0.07 (95% CI, 0.02-0.18); DOR, 89.0 (95% CI, 22.8-348.1). MRI had a high predictive accuracy in assessing both the depth and topography of placental invasion. All five MRI signs showed good predictive accuracy in the diagnosis of disorders of invasive placentation. There was no difference in either the sensitivity (P = 0.24) or the specificity (P = 0.91) between ultrasound and MRI for the detection of invasive placentation.
CONCLUSIONS
Prenatal MRI is highly accurate in diagnosing disorders of invasive placentation. Ultrasound and MRI have comparable predictive accuracy. Large population-based studies are needed in order to assess whether ultrasound can predict the depth and topography of placental invasion as reliably as can MRI.
Topics: Female; Humans; Magnetic Resonance Imaging; Models, Statistical; Placenta Accreta; Pregnancy; Prenatal Diagnosis; Sensitivity and Specificity
PubMed: 24515654
DOI: 10.1002/uog.13327 -
Ultrasound in Obstetrics & Gynecology :... Apr 2014To review systematically the medical literature reporting on the prevalence of a niche at the site of a Cesarean section (CS) scar using various diagnostic methods, on... (Review)
Review
OBJECTIVE
To review systematically the medical literature reporting on the prevalence of a niche at the site of a Cesarean section (CS) scar using various diagnostic methods, on potential risk factors for the development of a niche and on niche-related gynecological symptoms in non-pregnant women.
METHODS
The PubMed and EMBASE databases were searched. All types of clinical study reporting on the prevalence, risk factors and/or symptoms of a niche in non-pregnant women with a history of CS were included, apart from case reports and case series.
RESULTS
Twenty-one papers were selected for inclusion in the review. A wide range in the prevalence of a niche was found. Using contrast-enhanced sonohysterography in a random population of women with a history of CS, the prevalence was found to vary between 56% and 84%. Nine studies reported on risk factors and each study evaluated different factors, which made it difficult to compare studies. Risk factors could be classified into four categories: those related to closure technique, to development of the lower uterine segment or location of the incision or to wound healing, and miscellaneous factors. Probable risk factors are single-layer myometrium closure, multiple CSs and uterine retroflexion. Six out of eight studies that evaluated niche-related symptoms described an association between the presence of a niche and postmenstrual spotting.
CONCLUSIONS
The reported prevalence of a niche in non-pregnant women varies depending on the method of detection, the criteria used to define a niche and the study population. Potential risk factors can be categorized into four main categories, which may be useful for future research and meta-analyses. The predominant symptom associated with a niche is postmenstrual spotting.
Topics: Adult; Cesarean Section; Cicatrix; Dysmenorrhea; Female; Fertility; Humans; Metrorrhagia; Pelvic Pain; Pregnancy; Prevalence; Risk Factors; Uterine Diseases
PubMed: 23996650
DOI: 10.1002/uog.13199