Mullerian anomalies: revisiting imaging and classification

Mullerian duct anomalies (MDA) are a group of uncommon but treatable causes of infertility and pregnancy complications. This review describes the embryology, American Society of Reproductive Medicine (ASRM) classification 2021, and corresponding imaging features of MDA. The three phases of embryological development of Mullerian duct structures are described. The main emphasis is on the ASRM 2021 classification of MDA into nine descriptive categories, while the European Society of Human Reproduction and Embryology and the European Society for Gynecologic Endoscopy (ESHRE/ESGE) classification is also briefly described where necessary. MRI imaging features of MDA along with the acquisition techniques are discussed in detail, as MRI is the ideal imaging modality for MDA diagnosis. In addition, the current role of imaging modalities such as hysterosalpingography and ultrasound including 3D transvaginal ultrasound is also elucidated. The review aims to revisit the MRI imaging features of Mullerian anomalies and reiterates that an accurate description of each anomaly and precise communication with clinicians is the priority rather than rigidly fitting the anomaly into one particular category. CRITICAL RELEVANCE STATEMENT: The ASRM 2021 classification of Mullerian anomalies has re-defined the criteria for an arcuate uterus. Radiologists must know of the new classification and imaging features and try to describe each anomaly accurately rather than forcefully fitting an anomaly into a definite category. KEY POINTS: MDA has an important role in infertility and pregnancy complications. Knowledge of imaging features helps radiologists aid patient management; MRI is the preferred imaging modality for MDAs. An accurate MRI-based description of Mullerian anomalies is crucial, avoiding the pitfalls of rigid categorization.

Müllerian Duct Anomalies: Role in Fertility and Pregnancy

Müllerian duct anomalies (MDAs) have important implications for the reproductive health of female patients. In patients with both infertility and recurrent pregnancy loss, the incidence of MDAs is as high as 25%. Congenital uterine anomalies are often only part of a complex set of congenital anomalies involving the cervix, vagina, and urinary tract. Multiple classification systems for MDAs exist, each with different criteria that vary most for the diagnosis of septate uterus. Recognizing the features that guide clinical management is essential for interpretation. Identification of an MDA should prompt evaluation for associated urinary tract anomalies. In patients with infertility who seek to use assisted reproductive technologies such as intrauterine insemination, recognition of MDAs may have an affect on reproductive success, particularly in patients who have an incomplete and clinically occult septum that divides the cervix. Two-dimensional US is the first-line modality for evaluating the uterus and adnexa. Three-dimensional (3D) US or MRI may help to visualize the external uterine fundal contour and internal indentation of the endometrial cavity, which are two morphologic characteristics that are keys to the diagnosis of congenital uterine anomalies. Hysterosalpingo contrast-enhanced US may be performed in conjunction with 3D US to evaluate uterine morphologic characteristics, the endometrial cavity, and tubal patency in a single examination. MRI helps to characterize rudimentary uteri in patients with müllerian hypoplasia and allows assessment for ectopic ureters, abnormally positioned ovaries, or associated deep infiltrative endometriosis. Online supplemental material is available for this article. ©RSNA, 2021.

Magnetic Resonance Imaging of Uterine Cervix: A Pictorial Essay

Uterine cervix is the lower constricted part of uterus which is best evaluated by magnetic resonance imaging (MRI) due to its higher soft tissue and contrast resolution. The cervical cancer is a common gynecological cancer causing much morbidity and mortality especially in developing countries. Cervical carcinomas mainly occurs in reproductive age group with prognosis mainly depending on the extent of disease at the time of diagnosis, hence it is important to identify these cancerous lesions early and stage them accurately for optimal treatment. In this article, we will review the following: (1) the normal MRI anatomy of uterine cervix; (2) MRI protocol and techniques in evaluation of cervical lesions; (3) imaging of spectrum of various congenital abnormalities and pathologies affecting uterine cervix which ranges from congenital abnormalities to various benign lesions of cervix like nabothian cysts, tunnel cysts, cervicitis, cervical fibroid, and, lastly, endometriosis which usually coexists with adenomyosis; the malignant lesions include carcinoma cervix, adenoma malignum or direct extension from carcinoma endometrium or from carcinoma of vagina; (4) Accurately stage carcinoma of cervix using FIGO classification (2018); and (5) posttreatment evaluation of cervical cancers. MRI is the most reliable imaging modality in evaluation of various cervical lesions, identification of cervical tumors, staging of the cervical malignancy, and stratifying patients for surgery and radiation therapy. It also plays an important role in detection of local disease recurrence.

Pregnancy in a Unicornuate Uterus with Non-Communicating Rudimentary Horn: Diagnostic and Therapeutic Challenges

Unicornuate uterus with non-communicating rudimentary horn is a type of congenital uterine abnormality that occurs as a consequence of the arrested development of one of the two Müllerian ducts.

Patients with unicornuate uterus have increased incidence of obstetric and gynaecological complications.

We present a report of a clinical case of a 28-years-old female, who was referred to the hospital for evaluation of her infertility.

The patient reported primary infertility and inability to conceive after 3-year period of regular unprotected intercourse.

Transvaginal ultrasound, along with the preoperative evaluation were completed; however, no anomalies or irregularities were reported.

Combined diagnostic simultaneous laparoscopy and hysteroscopy were performed to establish the diagnosis of unicornuate uterus with non-communicating rudimentary horn.

The patient conceived spontaneously after diagnostic laparoscopy and hysteroscopy.

During and after pregnancy, our patient and her child experienced numerous complications (cervical incompetence, acute chorioamnionitis, acute fetal distress, pneumonia, septic shock) and procedures (cervical cerclage, urgent cesarean section, intensive care unit treatment) without significant fetal or maternal compromise.

Müllerian duct anomalies coincident with endometriosis: a review

The association between obstructed müllerian duct anomalies and endometriosis has been well established and the pathogenesis is attributed to the theory of retrograde menstruation. However, this relationship with endometriosis is less clear in women with unobstructed müllerian duct anomalies and in those with rudimentary uterine structures that lack functioning endometrial tissue. This article reviews the embryology, genetics, pathophysiology, and American Society for Reproductive Medicine (ASRM) classification for müllerian duct anomalies together with the genetics and pathophysiology of endometriosis to provide a framework for understanding the complex relationship between these two entities. Available published data examining the coexistence of endometriosis in relationship to müllerian duct anomalies, including studies that stratify this relationship according to specific classes of anomalies, are reviewed and organized. Awareness of the increased prevalence of endometriosis among patients with uterine anomalies, particularly those with outflow obstruction, may facilitate early diagnosis of endometriosis and subsequent intervention, with the potential to reverse disease symptoms and arrest disease progression.

MRI of female genital tract congenital anomalies: European Society of Urogenital Radiology (ESUR) guidelines

Objective

To develop imaging guidelines for the MR work-up of female genital tract congenital anomalies (FGTCA).

Methods

These guidelines were prepared based on a questionnaire sent to all members of the European Society of Urogenital Radiology (ESUR) Female Pelvic Imaging Working Group (FPI-WG), critical review of the literature and expert consensus decision.

Results

The returned questionnaires from 17 different institutions have shown reasonable homogeneity of practice. Recommendations with focus on patient preparation and MR protocol are proposed, as these are key to optimised examinations. Details on MR sequences and planning of uterus-orientated sequences are provided.

Conclusions

The multiplanar capabilities and soft tissue resolution of MRI provide superb characterisation of the wide spectrum of findings in FGTCA. A standardised imaging protocol and method of reporting ensures that the salient features are recognised, contributing to a correct diagnosis and classification of FGTCA, associated anomalies and complications. These imaging guidelines are based on current practice among expert radiologists in the field and incorporate up to date information regarding MR protocols and essentials of recently published classification systems.

Key Points

• MRI allows comprehensive evaluation of female genital tract congenital anomalies, in a single examination.

• A dedicated MRI protocol comprises uterus-orientated sequences and vaginal and renal evaluation.

• Integration of classification systems and structured reporting helps in successful communication of the imaging findings.

Electronic supplementary material

The online version of this article (10.1007/s00330-020-06750-8) contains supplementary material, which is available to authorized users.

Twin pregnancy in uteri with congenital anomalies: prenatal diagnosis by three- dimensional ultrasound

Objectives

To establish a practical and valid method for the diagnosis of twin gestation in uteri with Müllerian anomalies in the first trimester of pregnancy.

Case presentation

This was a prospective cohort study. Two cases with congenital uterine anomalies were followed prospectively from 7 weeks of gestation and compared to eight controls. The longitudinal to transverse uterine lumen diameter ratio (LTDR) was measured in mid-sagittal and coronal planes. The LTDR was compared between unicornuate and didelphys uteri to normal uteri controls weekly. The area under the curve for the coronal and sagittal planes were 1.000 and 0.823, respectively. For the coronal plane, an LTDR of 1.15 was selected as optimal for predicting uteri with a Müllerian anomaly, with a sensitivity of 100%, specificity of 100%. An LTDR of 1.68 in the sagittal plane was selected as optimal for predicting anomalous uteri, with a sensitivity of 100%, specificity of 73%.

Conclusions

LTDR ratios measured in mid sagittal and coronal planes of unicornuate and didelphys uteri with twin gestation during the first trimester of pregnancy are highly predictive of Müllerian anomalies. Early diagnosis of uterine anomalies could provide a reference to initiate earlier meticulous follow-up.

Diagnosis and Management of Congenital Uterine Anomalies in Pregnancy

Importance

Congenital uterine anomalies (CUAs) are strongly associated with adverse fertility and pregnancy outcomes. Health care providers must be able to diagnose these anomalies, understand their impact, and counsel women on interventions that might improve rates of pregnancy and live birth.

Objectives

The aims of this study were to characterize CUAs and their effects on adverse fertility and pregnancy outcomes, to describe the best imaging modalities to diagnose specific uterine anomalies, and to learn about interventions that may improve the reproductive outcomes of infertile and pregnant women.

Evidence Acquisition

A search of the PubMed database revealed 56 relevant studies, 49 of which were referenced in this comprehensive summary of the literature.

Results

Congenital uterine anomalies are strongly associated with recurrent pregnancy loss, low birth weight, preterm birth, hypertensive disorders of pregnancy, malpresentation, and cesarean delivery. Transvaginal 3-dimensional ultrasonography appears to be the best initial test for uterine anomaly evaluation. Prior to conception, women who undergo hysteroscopic metroplasty may have better fertility and pregnancy outcomes.

Conclusions and Relevance

Congenital uterine anomalies, although rare in the general population, pose significant challenges to women and their clinicians with regard to fertility and pregnancy management. Accurate diagnosis, preconception counseling and metroplasty, and antenatal monitoring may improve reproductive outcomes for women with CUAs.

Target Audience

Obstetricians and gynecologists, family physicians.

Learning Objectives

After completing this activity, the learner should be better able to (1) characterize congenital uterine anomalies and their potential effects on adverse fertility and pregnancy outcomes, (2) determine the best imaging modalities to diagnose specific uterine anomalies, and (3) counsel both infertile and pregnant patients about interventions that may improve their reproductive outcomes.

Magnetic resonance imaging of Müllerian duct anomalies in children

Müllerian duct anomalies encompass a wide variety of disorders resulting from abnormalities in the embryological development of the Müllerian ducts. In the prepubertal pediatric population, Müllerian duct anomalies are often incidental findings on studies obtained for other reasons. The onset of menses can prompt more clinical symptoms. Proper characterization of Müllerian duct anomalies is important because these anomalies can affect the development of gynecological disorders as well as fertility. Müllerian duct anomalies also carry a high association with other congenital anomalies, particularly renal abnormalities. MRI is widely considered the best modality for assessing Müllerian duct anomalies; it provides multiplanar capability, clear anatomical detail and tissue characterization without ionizing radiation. MRI allows for careful description of Müllerian duct anomalies, often leading to classification into the most widely accepted classification system for Müllerian duct anomalies. This system, developed by the American Society of Reproductive Medicine, includes seven subtypes: uterine agenesis/hypoplasia, unicornuate, didelphys, bicornuate, septate, arcuate, and diethylstilbestrol (DES) drug-related uterus. In cases of complex anomalies that defy classification, MRI allows detailed depiction of all components of the anatomical abnormality, allowing for proper management and surgical planning.

Magnetic Resonance Imaging of Abdominal and Pelvic Pain in the Pregnant Patient

The utility of MR imaging in evaluating abdominal and pelvic pain in the pregnant patient is discussed. Details regarding the indications, technical aspects, and imaging findings of various common abdominal and pelvic abnormalities in pregnancy are reviewed.

Extrafetal Findings on Fetal Magnetic Resonance Imaging: A Pictorial Essay

Although US is the mainstay of fetal imaging, magnetic resonance imaging (MRI) has become an invaluable adjunct in recent years. MRI offers superb soft tissue contrast that allows for detailed evaluation of fetal organs, particularly the brain, which enhances understanding of disease severity. MRI can yield results that are similar to or even better than those of US, particularly in cases of marked oligohydramnios, maternal obesity, or adverse fetal positioning. Incidentally detected extrafetal MRI findings are not uncommon and may affect clinical care. Physicians interpreting fetal MRI studies should be aware of findings occurring outside the fetus, including those structures important for the pregnancy. A systematic approach is necessary in the reading of such studies. This helps to ensure that important findings are not missed, appropriate clinical management is implemented, and unnecessary follow-up examinations are avoided. In this pictorial essay, the most common extrafetal abnormalities are described and illustrated.

Magnetic Resonance Imaging of Developmental Anomalies of the Uterus and the Vagina in Pediatric Patients

Developmental anomalies of the uterus and the vagina are associated with infertility and miscarriage and are most commonly detected in the postpubertal age-group. These conditions may also present in younger patients as a mass or pain owing to obstruction of the uterus or the vagina. Associated urinary tract anomalies are common, as well. Accurate diagnosis and thorough description of these anomalies is essential for appropriate management; however, evaluation may be difficult in an immature reproductive tract. Magnetic resonance imaging technique pertinent to imaging of the pediatric female reproductive tract is presented and illustrated along with the findings associated with various anomalies.