MR imaging in pelvic inflammatory disease: comparison with laparoscopy and US

Manifestations of Ovarian Cancer in Relation to Other Pelvic Diseases by MRI

Imaging plays a pivotal role in the diagnostic approach of women with suspected ovarian cancer. MRI is widely used for preoperative characterization and risk stratification of adnexal masses. While epithelial ovarian cancer (EOC) has typical findings on MRI; there are several benign and malignant pelvic conditions that may mimic its appearance on imaging. Knowledge of the origin and imaging characteristics of a pelvic mass will help radiologists diagnose ovarian cancer promptly and accurately. Finally, in special subgroups, including adolescents and gravid population, the prevalence of various ovarian tumors differs from that of the general population and there are conditions which uniquely manifest during these periods of life.

Identification and Treatment of Acute Pelvic Inflammatory Disease and Associated Sequelae

Pelvic inflammatory disease (PID) is an ascending polymicrobial infection of the upper female genital tract. The presentation of PID varies from asymptomatic cases to severe sepsis. The diagnosis of PID is often one of exclusion. Primary treatment for PID includes broad-spectrum antibiotics with coverage against gonorrhea, chlamydia, and common anaerobic and aerobic bacteria. If not clinically improved by antibiotics, percutaneous drain placement can promote efficient source control, as is often the case with large tubo-ovarian abscesses. Ultimately, even with treatment, PID can result in long-term morbidity, including chronic pelvic pain, infertility, and ectopic pregnancy.

Abdominal Pain in the Emergency Department: How to Select the Correct Imaging for Diagnosis

Abdominal pain is a common presenting complaint in the emergency department, and utilization of diagnostic imaging is often a key tool in determining its etiology. Plain radiography has limited utility in this population. Computed tomography (CT) is the imaging modality of choice for undifferentiated abdominal pain. Ultrasound and magnetic resonance imaging may be helpful in specific scenarios, primarily in pediatrics and pregnancy, and offer the benefit of eliminating ionizing radiation risk of CT. Guidance for imaging selection is determined by location of pain, special patient considerations, and specific suspected etiologies. Expert guidance is offered by the American College of Radiology Appropriateness Criteria^® which outlines imaging options based on location of pain.

Mimics and Pitfalls of Primary Ovarian Malignancy Imaging

The complex anatomy and similarity of imaging features of various pathologies in the pelvis can make accurate radiology interpretation difficult. While prompt recognition of ovarian cancer remains essential, awareness of processes that mimic ovarian tumors can avoid potential misdiagnosis and unnecessary surgery. This article details the female pelvic anatomy and highlights relevant imaging features that mimic extra-ovarian tumors, to help the radiologists accurately build a differential diagnosis of a lesion occupying the adnexa.

Diagnostic accuracy of pelvic imaging for acute pelvic inflammatory disease in an emergency care setting: a systematic review and meta-analysis

The aim of this review is to investigate the diagnostic accuracy or performance of contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) for acute pelvic inflammatory disease (PID) in an emergency care setting. We searched for studies on the diagnostic test accuracy of contrast-enhanced CT or MRI for women of reproductive age with acute abdominal pain using MEDLINE, Embase, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform, and ClinicalTrials.gov. The reference standard was gynecological examinations by gynecologists using standard diagnostic criteria with or without laparoscopy or transcervical endometrial biopsy. Two reviewers undertook screening of records, data extraction, and assessment of the risk of bias in each included study using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate model was used for the meta-analysis. Of 2,619 screened studies, three studies investigating contrast-enhanced CT and one study investigating MRI were eligible, including a total 635 patients and with a median prevalence of acute PID of 29%. All of the included studies had a high risk of bias for a reference standard and had some applicability concerns. Contrast-enhanced CT had a pooled sensitivity of 0.79 (95% confidence interval [CI], 0.52-0.93) and specificity of 0.99 (95% CI, 0.94-1.00). Magnetic resonance imaging had a sensitivity of 0.95 (95% CI, 0.76-1.00) and specificity of 0.89 (95% CI, 0.52-1.00). Contrast-enhanced CT might serve as a practical alternative to gynecological examination in the diagnosis of acute PID in an emergency care setting, however, the evidence was uncertain. The evidence on MRI was also very uncertain.

Chlamydia trachomatis, Pelvic Inflammatory Disease, and Epithelial Ovarian Cancer

Epidemiologic, clinical, molecular and translational research findings support an interrelationship between Chlamydia trachomatis, pelvic inflammatory disease (PID), and epithelial ovarian cancer (EOC). Overall, the link between C. trachomatis, PID, and EOC seems to be relatively weak, although nondifferential misclassification bias may have attenuated the results. The predominant tubal origin of EOC and the role of chronic inflammation in tumorigenesis suggest that the association is biologically plausible. Thus, C. trachomatis and PID may represent potential risk factors or risk markers for EOC. However, many steps in this chain of events are still poorly understood and need to be addressed in future studies. Research gaps include time of exposure in relation to the long-term consequences and lag time to EOC. Data of differential risk for EOC between chlamydial and nonchlamydial PID is also needed. Another major research gap has been the absence of high-performance biomarkers for C. trachomatis, PID, and EOC, as well as EOC precursors. Biomarkers for C. trachomatis and PID leading to increased risk of EOC should be developed. If the association is confirmed, C. trachomatis and PID prevention efforts may play a role in reducing the burden of EOC.

Problem-solving with MRI in acute abdominopelvic conditions, part 2: gynecological, obstetric, vascular, and renal diseases

The purpose of this article is to illustrate the benefits of magnetic resonance imaging (MRI) in the setting of abdominopelvic emergencies. Owing to intrinsically high soft-tissue contrast resolution, and ability to resolve different soft tissue, MRI holds notable advantages over other imaging modalities and can be used as a problem-solving tool. Additional advantages of MRI include lack of radiation-related risks to children and pregnant women, and the ability to acquire detailed diagnostic information even without intravenous contrast which can be beneficial in patients with contrast allergy and end-stage renal disease. In the part 2, the authors focus on MRI features of female pelvic gynecological diseases, pregnancy- related complications, abdominal vascular complications, and renal diseases.

Hysterosalpingography using Magnetic Resonance Imaging for infertility patients

OBJECTIVE

Some studies have shown that it is possible to evaluate tubal permeability through MRI. Our aim is to perform a prospective study and to perform a comprehensive review in the literature regarding HSG-MRI.

METHODS

We carried out a PUBMED search using the following keywords: hysterosalpingogram, hysterosalpingography, magnetic resonance imaging and MRI. As inclusion criteria, we included only papers published in English, and exams ran on humans. We also conducted a prospective inclusion of patients who had visited a human reproduction clinic between May/2017 and April/2019 for laboratory image diagnoses using HSG-MRI.

RESULTS

Following the inclusion and exclusion criteria, we included seven original papers. Review papers and those written in a language other than English, were excluded. Between the period of May/2017 and April/2019, we selected ten patients for our study. The average exam duration was 30 minutes. Cervical catheterization was possible in all cases. There were no major complications. We highlight that in 8/9 of patients, we could directly visualize uterine tubes with contrast (excluding one patient with bilateral tubal ligation).

CONCLUSIONS

Our initial experience with HSG-MRI shows promise. We demonstrated an optimized protocol for conducting an HSG-MRI (with excellent image quality). HSG-MRI had some advantages, such as not using ionized radiation, less pain and being able to analyze pelvic anatomy. Patients referred for a pelvic MRI as part of a more detailed investigation into infertility can also benefit from undergoing a simultaneous HSG using MRI.

Reproductive system infections in women: upper genital tract, fetal, neonatal and infant syndromes

Lower genital tract infection and bloodborne spread of infection are the two principal modes for infection of the upper genital tract or for infection of the fetus, neonate or infant. Treponema pallidum and human immunodeficiency virus (HIV) are the two most common bloodborne pathogens that infect the fetus, neonate or infant. Most infections of the upper genital tract, however, spread along epithelial surfaces from the vagina or cervix to the upper genital tract or chorioamnion, fetus, neonate or infant. These infections are caused by either pathogens associated with a dysbiotic vaginal microbiome or those that are sexually transmitted. The clinical syndromes that these pathogens produce in the lower genital tract were discussed in part one of this review. We now discuss the syndromes and pathogens that affect the upper genital tract of both non-pregnant and pregnant women as well as fetus, neonate and infant.

Imaging spectrum of common and rare infections affecting the lower genitourinary tract

In this review, we will discuss the imaging findings of common as well as uncommon lower genitourinary tract infections. For both clinicians and radiologists, it is imperative to understand etiopathogenesis, epidemiological information, clinical presentation, imaging findings and management options of such conditions. Knowledge of salient imaging features of these infections is of utmost importance because prompt recognition enables appropriate management.

Tubo-ovarian abscess: Exploring optimal treatment options based on current evidence

Purpose:

Tubo-ovarian abscess (TOA) and pelvic abscess are characterized by an inflammatory pelvic mass. In the majority of cases, this condition involves the ovaries, the fallopian tubes and/or any other adjacent tissue. TOA is considered a severe complication of PID and can cause severe sepsis. The main risk factors for women’s health are the size of the abscess, the initial amount of white blood cells (WBC), patients’ age as well as, any co-existing comorbidities.

Methods:

This study provides a review of the current literature regarding the management of TOA and the different criteria used in order to establish the optimal therapeutic approach or to predict outcome by individualizing cases. Four major search engines, MEDLINE, Google Scholar, PubMed and EMBASE, up to February 2020 were explored, focusing in epidemiology and risk factors, pathogenesis, diagnosis and treatment.

Results:

Our review suggests that there are no clear guidelines for best practice, in case of TOA, but it appears that intravenous antibiotics combined with interventional radiology have good results for TOA <5 cm. When TOA is >5 cm, laparoscopic approach is indicated. Further studies are needed in order to evaluate the best treatment for women with TOA.

Conclusions:

More prospective studies on large-series of patients are in need, in order to determine a clear pathway and to suggest specific criteria, which can guide clinicians to choose optimal approach in a timely manner.

ACR Appropriateness Criteria® Female Infertility

The most common known causes of female infertility are male factor (26%), ovulatory failure (21%), and tubal damage (14%), while in 28% a couple's infertility remains unexplained. Female-specific causes of infertility include deterioration of oocyte quality with increasing maternal age; ovulatory disorders, most notably polycystic ovarian syndrome; history of salpingitis such as that caused by chlamydia infection; endometriosis; and uterine cavity abnormalities interfering with implantation causing inability to become pregnant or causing recurrent pregnancy loss. These potential causes of female infertility are discussed in this document and the appropriate imaging recommendations for each variant are provided. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Niche role of MRI in the evaluation of female infertility

Infertility is a major social and clinical problem affecting 13-15% of couples worldwide. The pelvic causes of female infertility are categorized as ovarian disorders, tubal, peritubal disorders, and uterine disorders. Appropriate selection of an imaging modality is essential to accurately diagnose the aetiology of infertlity, since the imaging diagnosis directs the appropriate treatment to be instituted. Imaging evaluation begins with hystero- salpingography (HSG), to evaluate fallopian tube patency. Uterine filling defects and contour abnormalities may be discovered at HSG but usually require further characterization with pelvic ultrasound (US), sono-hysterography (syn: hystero-sonography/saline infusion sonography) or pelvic magnetic resonance imaging (MRI), when US remains inconclusive. The major limitation of hysterographic US, is its inability to visualize extraluminal pathologies, which are better evaluated by pelvic US and MRI. Although pelvic US is a valuable modality in diagnosing entities comprising the garden variety, however, extensive pelvic inflammatory disease, complex tubo-ovarian pathologies, deep-seated endometriosis deposits with its related complications, Mulllerian duct anomalies, uterine synechiae and adenomyosis, often remain unresolved by both transabdominal and transvaginal US. Thus, MRI comes to the rescue and has a niche role in resolving complex adnexal masses, endometriosis, and Mullerian duct anomalies with greater ease. This is a review, based on the authors' experience at tertiary care teaching hospitals and aims to provide an imaging approach towards the abnormalities which are not definitively diagnosed by ultrasound alone.

Cross-sectional imaging of acute gynaecologic disorders: CT and MRI findings with differential diagnosis-part II: uterine emergencies and pelvic inflammatory disease

Due to the growing use of cross-sectional imaging in emergency departments, acute gynaecologic disorders are increasingly diagnosed on urgent multidetector computed tomography (CT) studies, often requested under alternative presumptive diagnoses in reproductive-age women. If clinical conditions and state-of-the-art scanner availability permit, magnetic resonance imaging (MRI) is superior to CT due to its more in-depth characterisationof abnormal or inconclusive gynaecological findings, owing to excellent soft-tissue contrast, intrinsic multiplanar capabilities and lack of ionising radiation.

This pictorial review aims to provide radiologists with a thorough familiarity with gynaecologic emergencies by illustrating their CT and MRI appearances, in order to provide a timely and correct imaging diagnosis. Specifically, this second instalment reviews with examples and emphasis on differential diagnosis the main non-pregnancy-related uterine emergencies (including endometrial polyps, degenerated leiomyomas and uterine inversion) and the spectrum of pelvic inflammatory disease.

MRI of Acute Gynecologic Conditions

Although usually not a first-line imaging modality in the setting of acute pelvic pain, magnetic resonance imaging (MRI) is able to depict and characterize a wide range gynecologic diagnoses with high accuracy. Lack of ionizing radiation renders MRI particularly useful for assessment of pregnant women and children. Furthermore, inherent high soft-tissue resolution of MRI allows accurate diagnosis without intravenous contrast use, which is advantageous for patients with renal insufficiency and pregnant patients. Familiarity with the typical MRI appearance of various acute gynecologic conditions helps establish the correct diagnosis. This article reviews the common MRI findings of acute gynecologic processes, in both pregnant and nonpregnant patients. Level of Evidence: 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2020;51:1291-1309.

Imaging Modalities in Genitourinary Emergencies

Emergency physicians rely on a multitude of different imaging modalities in the diagnosis of genitourinary emergencies. There are many considerations to be taken into account when deciding which imaging modality should be used first, as oftentimes several diagnostic tools can be used for the same pathologic condition. These factors include radiation exposure, sensitivity, specificity, age of patient, availability of resources, cost, and timeliness of completion. In this review, the strengths and weaknesses of different imaging tools in the evaluation of genitourinary emergencies are discussed.

[Acute Pelvic pain in women-gynecological causes]

BACKGROUND

Acute pelvic pain in women may be due to gynecological, gastrointestinal, and urinary tract disorders. Ectopic pregnancy (EP), pelvic inflammatory disease (PID), and ruptured ovarian cysts are the most common gynecological causes for acute pelvic pain and their diagnosis can be challenging.

METHODS

Patient history, clinical examination, and blood tests as well as patient age and potential pregnancy status help to establish the correct diagnosis. While sonography (US) remains the primary imaging modality of choice, computed tomography (CT) plays an important role in patients with indeterminate US evaluation and for treatment planning.

CONCLUSION

Diagnostic imaging is pivotal to differentiate potentially life- and fertility-threatening conditions from those that can be treated conservatively. Profound knowledge of the most common gynecological pathologies allows prompt and correct radiological diagnosis and assists in proper treatment planning.

MRI versus laparoscopy to diagnose the main causes of chronic pelvic pain in women: a test-accuracy study and economic evaluation

BACKGROUND

Chronic pelvic pain (CPP) symptoms in women are variable and non-specific; establishing a differential diagnosis can be hard. A diagnostic laparoscopy is often performed, although a prior magnetic resonance imaging (MRI) scan may beneficial.

OBJECTIVES

To estimate the accuracy and added value of MRI in making diagnoses of (1) idiopathic CPP and (2) the main gynaecological causes of CPP. To quantify the impact MRI can have on decision-making with respect to triaging for therapeutic laparoscopy and to conduct an economic evaluation.

DESIGN

Comparative test-accuracy study with cost-effectiveness modelling.

SETTING

Twenty-six UK-based hospitals.

PARTICIPANTS

A total of 291 women with CPP.

METHODS

Pre-index information concerning the patient's medical history, previous pelvic examinations and ultrasound scans was collected. Women reported symptoms and quality of life at baseline and 6 months. MRI scans and diagnostic laparoscopy (undertaken and interpreted blind to each other) were the index tests. For each potential cause of CPP, gynaecologists indicated their level of certainty that the condition was causing the pelvic pain. The analysis considered both diagnostic laparoscopy as a reference standard for observing structural gynaecological causes and consensus from a two-stage expert independent panel for ascertaining the cause of CPP. The stage 1 consensus was based on pre-index, laparoscopy and follow-up data; for stage 2, the MRI scan report was also provided. The primary analysis involved calculations of sensitivity and specificity for the presence or absence of each structural gynaecological cause of pain. A decision-analytic model was developed, with a 6-month time horizon. Two strategies, laparoscopy or MRI, were considered and populated with study data.

RESULTS

Using reference standards of laparoscopic and expert panel diagnoses, MRI scans had high specificity but poor sensitivity for observing deep-infiltrating endometriosis, endometrioma, adhesions and ovarian cysts. MRI scans correctly identified 56% [95% confidence interval (CI) 48% to 64%] of women judged to have idiopathic CPP, but missed 46% (95% CI 37% to 55%) of those considered to have a gynaecological structural cause of CPP. MRI added significant value, over and above the pre-index information, in identifying deep-infiltrating endometriosis (p = 0.006) and endometrioma (p = 0.02) as the cause of pain, but not for other gynaecological structural causes or for identifying idiopathic CPP (p = 0.08). Laparoscopy was significantly more accurate than MRI in diagnosing idiopathic CPP (p < 0.0001), superficial peritoneal endometriosis (p < 0.0001), deep-infiltrating endometriosis (p < 0.0001) and endometrioma of the ovary (p = 0.02) as the cause of pelvic pain. The accuracy of laparoscopy appeared to be able to rule in these diagnoses. Using MRI to identify women who require therapeutic laparoscopy would lead to 369 women in a cohort of 1000 receiving laparoscopy unnecessarily, and 136 women who required laparoscopy not receiving it. The economic analysis highlighted the importance of the time horizon, the prevalence of CPP and the cut-off values to inform the sensitivity and specificity of MRI and laparoscopy on the model results. MRI was not found to be a cost-effective diagnostic approach in any scenario.

CONCLUSIONS

MRI was dominated by laparoscopy in differential diagnosis of women presenting to gynaecology clinics with CPP. It did not add value to information already gained from history, examination and ultrasound about idiopathic CPP and various gynaecological conditions.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN13028601.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 40. See the NIHR Journals Library website for further project information.

Tales from the Night:: Emergency MR Imaging in Pediatric Patients after Hours

Overnight in-house radiology has rapidly become an important part of contemporary practice models, and is increasingly the norm in pediatric radiology. MR imaging is an indispensable first-line and problem-solving tool in the pediatric population. This has led to increasingly complex MR imaging being performed "after hours" on pediatric patients. This article reviews the factors that have led to widespread overnight subspecialty radiology and the associated challenges for overnight radiologists, and provides an overview of up-to-date imaging techniques and imaging findings of the most common indications for emergent MR imaging in the pediatric population.

National Institute of Allergy and Infectious Diseases workshop report: "Chlamydia vaccines: The way forward"

Chlamydia trachomatis (Ct), an intracellular pathogen, is the most common bacterial sexually transmitted infection. In addition to acute cervicitis and urethritis, Ct can lead to serious sequelae of significant public health burden including pelvic inflammatory disease (PID) and infertility. Ct control efforts have not resulted in desired outcomes such as reduced incidence and reinfection, and this highlights the need for the development of an effective Ct vaccine. To this end, NIAID organized a workshop to consider the current status of Ct vaccine research and address critical questions in Ct vaccine design and clinical testing. Topics included the goal(s) of a vaccine and the feasibility of achieving these goals, animal models of infection including mouse and nonhuman primate (NHP) models, and correlates of protection to guide vaccine design. Decades of research have provided both whole cell-based and subunit vaccine candidates for development. At least one is currently in clinical development and efforts now need to be directed toward further development of the most attractive candidates. Overall, the discussions and presentations from the workshop highlighted optimism about the current status of Ct vaccine research and detailed the remaining gaps and questions needed to move vaccines forward.

Diagnostic Evaluation of Chronic Pelvic Pain

Chronic pelvic pain can result from various intra- and extra-pelvic etiologies. Although patient history and physical examination may narrow the differential diagnosis, frequently, the different etiologies have overlapping presentations. Imaging examinations such as US and/or MR imaging may help delineate the cause of pain, particularly when related to intra-pelvic organs, pelvic floor dysfunction or prolapse, synthetic material such as pelvic mesh or slings, and in some cases of neuropathic pain. Etiologies of neuropathic pain can also be assessed with non-imaging tests such as nerve conduction studies, electromyography, and testing of sacral reflexes.

Imaging after treatment in uterine malignancies: Spectrum of normal findings and most common complications

Uterine malignancies account for the majority of gynaecologic cancers. Different treatment options are available depending on histology, disease grade and stage. Hysterectomy is the most frequent surgical procedure. Chemotherapy and radiation therapy (CRT) represents the preferred therapeutic choice for locally advanced uterine and cervical malignancies. Imaging of the female pelvis following these treatments is particularly challenging due to alteration of the normal anatomy. Radiologists should be familiar with both the expected post-treatment imaging findings and the imaging features of possible complications to make the correct interpretation and avoid possible pitfalls. The purpose of this review is to show the expected computed tomography (CT) and Magnetic Resonance Imaging (MRI) appearances of the female pelvis following surgery and CRT for uterine and cervical cancer, to illustrate the imaging findings of early and delayed most common complications after surgery and CRT, describing the suitable imaging modalities and protocols for evaluation of patients treated for gynaecologic malignancies.

Update on Chlamydia trachomatis Vaccinology

Attempts to produce a vaccine to protect against Chlamydia trachomatis-induced trachoma were initiated more than 100 years ago and continued for several decades. Using whole organisms, protective responses were obtained. However, upon exposure to C. trachomatis, disease exacerbation developed in some immunized individuals, precluding the implementation of the vaccine. Evidence of the role of C. trachomatis as a sexually transmitted pathogen started to emerge in the 1960s, and it soon became evident that it can cause acute infections and long-term sequelae in women, men, and newborns. The main focus of this minireview is to summarize recent findings and discuss formulations, including antigens, adjuvants, routes, and delivery systems for immunization, primarily explored in the female mouse model, with the goal of implementing a vaccine against C. trachomatis genital infections.

MRI in pelvic inflammatory disease: a pictorial review

Pelvic inflammatory disease (PID) is an ascending infection of the female genital tract caused by the spread of bacteria from the vagina to the pelvic reproductive organs and occasionally the peritoneum. The most common causative organisms are sexually transmitted. PID is a significant source of morbidity among reproductive age women both as a cause of abdominal pain and as a common cause of infertility. Its clinical presentation is often nonspecific, and the correct diagnosis may first come to light based on the results of imaging studies. MRI is well suited for the evaluation of PID and its complications due to its superior soft tissue contrast and high sensitivity for inflammation. MRI findings in acute PID include cervicitis, endometritis, salpingitis/oophoritis, and inflammation in the pelvic soft tissues. Acute complications include pyosalpinx, tuboovarian abscess, peritonitis, and perihepatitis. Hydrosalpinx, pelvic inclusion cysts and ureteral obstruction may develop as chronic sequela of PID. The pathophysiology, classification, treatment, and prognosis of PID are reviewed, followed by case examples of the appearance of acute and subclinical PID on MR images.

Status of vaccine research and development of vaccines for Chlamydia trachomatis infection

Genital infection with Chlamydia trachomatis, a gram-negative obligate intracellular bacterium, is the most common bacterial sexually transmitted infection globally. Ascension of chlamydial infection to the female upper genital tract can cause acute pelvic inflammatory disease, tubal factor infertility, ectopic pregnancy, and chronic pelvic pain. Shortcomings of current chlamydia control strategies, especially for low- and middle-income countries, highlight the need for an effective vaccine. Evidence from animal models, human epidemiological studies, and early trachoma vaccine trials suggest that a C. trachomatis vaccine is feasible. Vaccine development for genital chlamydial infection has been in the preclinical phase of testing for many years, but the first Phase I trials of chlamydial vaccine candidates are underway, and scientific advances hold promise for additional candidates to enter clinical evaluation in the coming years. We describe the clinical and public health need for a C. trachomatis vaccine, provide an overview of Chlamydia vaccine development efforts, and summarize current vaccine candidates in the development pipeline.

Pelvic Inflammatory Disease: Multimodality Imaging Approach with Clinical-Pathologic Correlation

Pelvic inflammatory disease (PID) is a common medical problem, with almost 1 million cases diagnosed annually. Historically, PID has been a clinical diagnosis supplemented with the findings from ultrasonography (US) or magnetic resonance (MR) imaging. However, the diagnosis of PID can be challenging because the clinical manifestations may mimic those of other pelvic and abdominal processes. Given the nonspecific clinical manifestations, computed tomography (CT) is commonly the first imaging examination performed. General CT findings of early- and late-stage PID include thickening of the uterosacral ligaments, pelvic fat stranding with obscuration of fascial planes, reactive lymphadenopathy, and pelvic free fluid. Recognition of these findings, as well as those seen with cervicitis, endometritis, acute salpingitis, oophoritis, pyosalpinx, hydrosalpinx, tubo-ovarian abscess, and pyometra, is crucial in allowing prompt and accurate diagnosis. Late complications of PID include tubal damage resulting in infertility and ectopic pregnancy, peritonitis caused by uterine and/or tubo-ovarian abscess rupture, development of peritoneal adhesions resulting in bowel obstruction and/or hydroureteronephrosis, right upper abdominal inflammation (Fitz-Hugh-Curtis syndrome), and septic thrombophlebitis. Recognition of these late manifestations at CT can also aid in proper patient management. At CT, careful assessment of common PID mimics, such as endometriosis, adnexal torsion, ruptured hemorrhagic ovarian cyst, adnexal neoplasms, appendicitis, and diverticulitis, is important to avoid misinterpretation, delay in management, and unnecessary surgery. Correlation with the findings from complementary imaging examinations, such as US and MR imaging, is useful for establishing a definitive diagnosis. (©)RSNA, 2016.

Magnetic resonance imaging of acquired disorders of the pediatric female pelvis other than neoplasm

Transabdominal US remains the primary screening imaging modality of the pediatric female pelvis. However, MRI has become an invaluable adjunct to US in recent years. MRI offers superb soft-tissue contrast resolution that allows for detailed evaluation, particularly of the ovaries and their associated pathology. MRI can yield diagnostic information that is similar to or even better than that of US, especially in nonsexually active girls in whom transvaginal US would be contraindicated. MRI is generally a second-line examination and is preferred over CT because it does not involve the use of ionizing radiation. MRI might be underutilized in this population, particularly in differentiating surgical from nonsurgical conditions. This article reviews the relevant anatomy and discusses imaging of acquired conditions that involve the pediatric female genital tract, illustrating associated pathology with case examples.

Non-neoplastic diseases of the fallopian tube: MR imaging with emphasis on diffusion-weighted imaging

OBJECTIVE

We illustrate the magnetic resonance imaging (MRI) features of non-neoplastic tubaric conditions.

BACKGROUND

A variety of pathologic non-neoplastic conditions may affect the fallopian tubes. Knowledge of their imaging appearance is important for correct diagnosis. With recent advances in MRI, along with conventional MR sequences, diffusion-weighted imaging (DWI) sequences are available and may improve lesion characterization by discriminating the nature of the content of the dilated tube. Tubal fluid with low signal intensity on T1-weighted images, high signal intensity on T2-weighted images and no restricted diffusion on DWI is indicative of hydrosalpinx. Content with high signal intensity on T1-weighted images and restricted diffusion on DWI is suggestive of hematosalpinx associated with endometriosis or tubal pregnancy. A dilated tube with variable or heterogeneous signal intensity content on conventional MR sequences and restricted diffusion on DWI may suggest a pyosalpinx or tubo-ovarian abscess. We describe morphological characteristics, MR signal intensity features, enhancement behaviour and possible differential diagnosis of each lesion.

CONCLUSION

MRI is the method of choice to study adnexal pelvic masses. Qualitative and quantitative functional imaging with DWI can be of help in characterization of tubaric diseases, provided that findings are interpreted in conjunction with those obtained with conventional MRI sequences.

TEACHING POINTS

• Nondilated fallopian tubes are not usually seen on MR images. • MRI is the method of choice to characterize and localize utero-adnexal masses. • MRI allows characterization of lesions through evaluation of the fluid content's signal intensity. • DWI in conjunction with conventional MRI sequences may improve tissue characterization. • Pelvic inflammatory disease is the most common tubal pathology.

Tubo-Ovarian Abscess (with/without Pseudotumor Area) Mimicking Ovarian Malignancy: Role of Diffusion-Weighted MR Imaging with Apparent Diffusion Coefficient Values

Objective

To assess the added value of diffusion-weighted magnetic resonance imaging (DWI) with apparent diffusion coefficient (ADC) values compared to MRI, for characterizing the tubo-ovarian abscesses (TOA) mimicking ovarian malignancy.

Materials and Methods

Patients with TOA (or ovarian abscess alone; n = 34) or ovarian malignancy (n = 35) who underwent DWI and MRI were retrospectively reviewed. The signal intensity of cystic and solid component of TOAs and ovarian malignant tumors on DWI and the corresponding ADC values were evaluated, as well as clinical characteristics, morphological features, MRI findings were comparatively analyzed. Receiver operating characteristic (ROC) curve analysis based on logistic regression was applied to identify different imaging characteristics between the two patient groups and assess the predictive value of combination diagnosis with area under the curve (AUC) analysis.

Results

The mean ADC value of the cystic component in TOA was significantly lower than in malignant tumors (1.04 ± 0 .41 × 10⁻³ mm²/s vs. 2.42 ± 0.38 × 10⁻³ mm²/s; p < 0.001). The mean ADC value of the enhanced solid component in 26 TOAs was 1.43 ± 0.16×10⁻³mm²/s, and 46.2% (12 TOAs; pseudotumor areas) showed significantly higher signal intensity on DW-MRI than in ovarian malignancy (mean ADC value 1.44 ± 0.20×10⁻³ mm²/s vs.1.18 ± 0.36 × 10⁻³ mm²/s; p = 0.043). The combination diagnosis of ADC value and dilated tubal structure achieved the best AUC of 0.996. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of MRI vs. DWI with ADC values for predicting TOA were 47.1%, 91.4%, 84.2%, 64%, and 69.6% vs. 100%, 97.1%, 97.1%, 100%, and 98.6%, respectively.

Conclusions

DW-MRI is superior to MRI in the assessment of TOA mimicking ovarian malignancy, and the ADC values aid in discriminating the pseudotumor area of TOA from the solid portion of ovarian malignancy.

Staging, surveillance, and evaluation of response to therapy in renal cell carcinoma: role of MDCT

Renal cell carcinoma is the most common malignant renal tumor in the adults. Significant advances have been made in the management of localized and advanced renal cell carcinoma. Surgery is the standard of care and accurate pre-operative staging based on imaging is critical in guiding appropriate patient management. Besides staging, imaging plays a key role in the post-operative surveillance and evaluation of response to systemic therapies. Both CT and MR are useful in the staging and follow up of renal cell carcinoma, but CT is more commonly used due to its lower costs and wider availability. In this article, we discuss and illustrate the role of multi-detector CT in pre-operative staging, post-operative surveillance, and evaluation of response to systemic therapy in renal cell carcinoma.

Pelvic inflammatory disease: identifying research gaps--proceedings of a workshop sponsored by Department of Health and Human Services/National Institutes of Health/National Institute of Allergy and Infectious Diseases, November 3-4, 2011

In November 2011, the National Institutes of Health convened a workshop of basic researchers, epidemiologists, and clinical experts in pelvic inflammatory disease to identify research gaps hindering advances in diagnosis, treatment, and prevention. This article summarizes the presentations, discussions, and conclusions of this group and highlights significant controversies that reveal aspects of pelvic inflammatory disease research that would most greatly benefit from the application of newer molecular, immunologic, and radiologic techniques. Multiple limitations to performing new clinical trials exist; however, emerging data from ongoing clinical trials will add to the current body of knowledge regarding prevention and treatment strategies. In addition, use of established health care databases could serve as a valuable tool for performance of unbiased epidemiologic outcome studies.