Seminars in Ultrasound Ct and Mri最新文献

The most common origin of a non-uterine pelvic mass is from the ovary. Ultrasound is the initial imaging modality of choice, additional imaging with computed tomography (CT) and/or magnetic resonance imaging (MRI) is performed in selected cases. Adnexal masses are also encountered as incidental findings during ultrasound, CT or MRI. Many of the adnexal masses that are surgically removed are benign. For optimal outcome and cost effective management, noninvasive risk stratification of such adnexal masses is necessary when discovered incidentally or when identified in a patient with a clinically detected pelvic mass. The American College of Radiology Ovarian-Adnexal Reporting Data System is a pattern-based scoring system for adnexal masses imaged with ultrasound and MRI, which assists clinicians to guide in the appropriate management based on evidence-based risk categories. Non-ovarian and non-uterine pelvic masses include fallopian tube abnormalities, paraovarian cysts, peritoneal inclusion cysts, and rare causes include masses that arise from the gastrointestinal tract or the sacrum. To distinguish non-ovarian masses from an ovarian tumor, a critical step is to identify a normal appearing ovary separate from the pelvic mass. This may be challenging in the post-menopausal woman with an atrophic ovary. MRI is a useful adjunctive modality in such cases. Extraovarian masses typically displace pelvic side wall vasculature medially, compress, encase or medially displace the ureters.

Acute pelvic pain is defined as a new symptom that has been present for less than 3 months. It is a common symptom seen in 15%-24% of women and is the indication for 20% of laparoscopies and 2%-10% of outpatient gynecologic visits. The pregnancy status and correlation of the physical symptoms with clinical findings are important. Ultrasound is the imaging modality of choice, not only to diagnose gynecological causes, but also bowel or urinary tract related causes of pelvic pain. When an ultrasound scan is inconclusive, a computed tomography scan is the preferred means of additional imaging and is particularly useful in gastrointestinal and urogenital causes of pelvic pain. Gynecological causes of acute pelvic pain include uterine, tubal, or ovarian pathology; non-gynecological causes include bowel diseases, such as appendicitis and diverticulitis; urogenital causes such as ureteral, bladder stones, and urinary tract infection as well as vascular causes. Ultrasound imaging alone may provide a definitive diagnosis in underlying conditions that require prompt medical or surgical intervention in gynecological conditions, such as ovarian torsion, ectopic pregnancy, and non-gynecological condition, such as in acute appendicitis.

Abnormal uterine bleeding (AUB) is defined by the International Federation of Gynecology and Obstetrics as bleeding from the uterine corpus that is abnormal in regularity, volume, frequency, or duration and occurs in the absence of pregnancy. AUB is a common condition that affects about a third of women in their lifetime. Abnormal bleeding in duration, quantity, or timing consists of 2 categories, predictable cyclical heavy menstrual bleeding (HMB) and irregular non-cyclical intermenstrual bleeding (IMB). The most common causes of HMB include fibroids and adenomyosis and IMB is commonly caused by ovulatory dysfunction such as in polycystic ovaries, endometrial polyp, or an IUD. A pelvic ultrasound is the initial and often only imaging modality needed in the imaging evaluation of abnormal uterine bleeding and can accurately identify the common causes of abnormal uterine bleeding in the reproductive age group.

Post-menopausal bleeding (PMB) accounts for 5% of gynecologic office visits and is the presenting symptom in 90% of women with endometrial cancer, which requires prompt evaluation. The most common etiology of PMB is vaginal or endometrial atrophy and endometrial polyps, while endometrial hyperplasia and carcinoma account for less than 10% of PMB. Transvaginal ultrasonography measurement of an endometrial thickness (EMT) less than or equal to 4 mm has a 99% negative predictive value for endometrial carcinoma. Endometrial sampling is required if EMT >4 mm or persistent bleeding occurs. Further evaluation can be accomplished with saline infusion sonography, magnetic resonance imaging, and hysteroscopy.

Uterine masses are commonly encountered as incidental findings during cross-sectional imaging or when individuals present with symptoms such as pain and bleeding. The World Health Organization categorizes tumors of the uterine corpus into 5 distinct groups: endometrial epithelial tumors and their precursors, tumor-like growths, mesenchymal uterine tumors, tumors with a combination of epithelial and mesenchymal elements, and various other types of tumors. The primary imaging method for assessing uterine abnormalities is transvaginal ultrasound. However, magnetic resonance imaging (MRI) can be employed to enhance the visualization of soft tissues, enabling a more detailed characterization of uterine masses. This article aims to outline the imaging features of both benign and malignant uterine masses using ultrasound, MRI, and computed tomography.

Myelitis is an extensive group of pathologies, including inflammatory, demyelinating, and infectious disorders, sometimes mimicking tumors. This article will discuss infectious myelitis, mainly the patterns of spinal cord involvement caused by each infectious agent and the contribution of magnetic resonance imaging as a major tool to establish the specific diagnosis.

Spinal cord tumors are uncommon, and its multiple representatives not always have pathognomonic characteristics, which poses a challenge for both patients and caring physicians. The radiologist performs an important role in recognizing these tumors, as well as in differentiating between neoplastic and non-neoplastic processes, supporting clinical and surgical decision-making in patients with spinal cord injury. Magnetic Resonance Imaging (MRI) assessment, paired with a deep understanding of the various patterns of cord involvement allied to detailed clinical data can provide a diagnosis or significantly limit the differential diagnosis in most cases. In this article, we aim to review the most common and noteworthy intramedullary and extramedullary spinal tumors, as well as some other tumoral mimics, with an emphasis on their MRI morphologic characteristics.

There are many vascular disorders that can affect the spinal cord, and their prevalence and etiology are highly influenced by age, sex, and risk factors. This article reviews the embryology and anatomy of the spinal cord, as well as several vascular conditions, describing their clinical and imaging presentation, emphasizing the different imaging modalities’ contributions to increasing specificity and better defining the most appropriate therapy strategy for improving the patient's prognosis.