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Gynecological Imaging

Imaging of the internal female reproductive organs (including the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy, ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy, and fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy) is indicated to diagnose common gynecologic complaints, most commonly in cases of abnormal bleeding, pelvic pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, and to evaluate masses, congenital Congenital Chorioretinitis anomalies, and infertility Infertility Infertility is the inability to conceive in the context of regular intercourse. The most common causes of infertility in women are related to ovulatory dysfunction or tubal obstruction, whereas, in men, abnormal sperm is a common cause. Infertility. Ultrasound is almost always the 1st-line imaging modality of choice, whereas MRI is typically reserved for complicated or indeterminate cases as a follow-up. Computed tomography is almost never used for primary gynecologic assessments. Fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy are not visible on either ultrasound or MRI if they are normal. The best way to assess tubal patency is by using hysterosalpingography Hysterosalpingography Radiography of the uterus and fallopian tubes after the injection of a contrast medium. Congenital Malformations of the Female Reproductive System, a fluoroscopic exam in which a dye is injected into the uterine cavity, followed by the study of its flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure through the fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy.

Last updated: Dec 20, 2021

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Internal gynecologic organs commonly evaluated on imaging

  • Uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy
  • Ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy
  • Fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy

Studies of choice for gynecologic imaging

  • Ultrasound: almost always the initial study of choice
  • Pelvic MRI: typically reserved for cases that are indeterminate on ultrasound
  • Hysterosalpingography Hysterosalpingography Radiography of the uterus and fallopian tubes after the injection of a contrast medium. Congenital Malformations of the Female Reproductive System (HSG): a fluoroscopic exam used to assess tubal patency
  • Note on CT scans:
    • Generally not used to image the female reproductive organs (poorer resolution than ultrasound)
    • May be indicated as part of an oncology workup to look for evidence of metastasis Metastasis The transfer of a neoplasm from one organ or part of the body to another remote from the primary site. Grading, Staging, and Metastasis to the lymph nodes Lymph Nodes They are oval or bean shaped bodies (1 – 30 mm in diameter) located along the lymphatic system. Lymphatic Drainage System: Anatomy or other abdominal organs
    • Gynecologic pathology may be identified on CT scan (e.g., during a workup for lower abdominal pain Abdominal Pain Acute Abdomen in the ED) → typically followed up with pelvic ultrasound for better evaluation

Preparation

Prior to the interpretation of any image, the physician should take certain preparatory steps. The same systematic approach should be followed every time:

  • Confirm the name, date, and time on all images.
  • Obtain the medical history and perform physical examination.
  • Confirm the appropriate exam and technique for the desired pathology.
  • Compare any available images of the same area taken in the same modality.
  • Determine image orientation Orientation Awareness of oneself in relation to time, place and person. Psychiatric Assessment:
    • Right or left marker on X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests
    • In an ultrasound, standard exam views place a marker (dot) on the right.
    • For CT/MRI: on axial Axial Computed Tomography (CT) view, the image is sliced and viewed from inferior to superior (as if you are looking from the subject’s feet up).

Ultrasonography

Indications

Ultrasound (i.e., sonography Sonography The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1. 6 to 10 megahertz. Diagnostic Procedures in Gynecology) is almost always the imaging modality of choice when evaluating the internal female reproductive organs. Indications include:

  • Suspected ovarian or fallopian tube Fallopian Tube A pair of highly specialized canals extending from the uterus to its corresponding ovary. They provide the means for ovum transport from the ovaries and they are the site of the ovum’s final maturation and fertilization. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells. Uterus, Cervix, and Fallopian Tubes: Anatomy masses:
  • Abnormal uterine bleeding Abnormal Uterine Bleeding Abnormal uterine bleeding is the medical term for abnormalities in the frequency, volume, duration, and regularity of the menstrual cycle. Abnormal uterine bleeding is classified using the acronym PALM-COEIN, with PALM representing the structural causes and COEIN indicating the non-structural causes. Abnormal Uterine Bleeding:
    • Abnormal menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle, including irregularities in frequency, duration, and volume
    • In pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care
    • Postmenopausal bleeding
  • Pelvic pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways (looking for structural causes)
  • Assessment of the presence and location of intrauterine devices Intrauterine devices Contraceptive devices placed high in the uterine fundus. Hormonal Contraceptives ( IUDs IUDs Contraceptive devices placed high in the uterine fundus. Hormonal Contraceptives)
  • Evaluation of congenital Congenital Chorioretinitis anomalies
  • Infertility Infertility Infertility is the inability to conceive in the context of regular intercourse. The most common causes of infertility in women are related to ovulatory dysfunction or tubal obstruction, whereas, in men, abnormal sperm is a common cause. Infertility
  • Routine pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care assessments:
    • Dating
    • Cervical length
    • Anatomic, fluid, growth, and position assessments of the fetus
  • Visual assistance with other invasive procedures, including:
    • Aspiration of ova for in vitro fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week
    • Aspiration of pelvic fluid
    • Indications in obstetrics include:
      • Amniocentesis Amniocentesis Percutaneous transabdominal puncture of the uterus during pregnancy to obtain amniotic fluid. It is commonly used for fetal karyotype determination in order to diagnose abnormal fetal conditions. Polyhydramnios
      • Chorionic villus sampling

Advantages

  • Low cost
  • No radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma
  • Widespread availability
  • Rapid
  • Very good visualization of the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy and ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy

Disadvantages

  • Lower resolution than MRI
  • Technician dependent

Types of routine studies and techniques

Transvaginal ultrasound Transvaginal Ultrasound Obstetric Imaging (TVUS):

  • Allows for the best visualization of the female reproductive structures located within the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy
  • Positioning: dorsal lithotomy
  • Transducer Transducer A device placed on the patient’s body to visualize a target Ultrasound (Sonography) is placed inside the vagina Vagina The vagina is the female genital canal, extending from the vulva externally to the cervix uteri internally. The structures have sexual, reproductive, and urinary functions and a rich blood supply, mainly arising from the internal iliac artery. Vagina, Vulva, and Pelvic Floor: Anatomy.
  • Transducer Transducer A device placed on the patient’s body to visualize a target Ultrasound (Sonography) is typically:
    • At or below the cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy
    • Angled slightly upward to visualize the reproductive organs

Transabdominal ultrasound (TAUS):

  • Positioning: supine
  • Performed on a full bladder Bladder A musculomembranous sac along the urinary tract. Urine flows from the kidneys into the bladder via the ureters, and is held there until urination. Pyelonephritis and Perinephric Abscess (pushes away loops of bowel for better visualization of the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy)
  • Transducer Transducer A device placed on the patient’s body to visualize a target Ultrasound (Sonography) is placed on the lower abdomen.
  • Best for visualizing structures above the true pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy, such as:
    • An enlarged uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy (e.g., during pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care)
    • Large cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change or fibroids Fibroids A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the uterus and the gastrointestinal tract but can occur in the skin and subcutaneous tissue, probably arising from the smooth muscle of small blood vessels in these tissues. Infertility extending out of the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy
  • Useful in people who cannot tolerate transvaginal exams

Depth and gain:

  • Determines the field of view and echogenicity characteristics of the tissue
  • Gain should be placed such that the parenchyma is visualized without saturating out (“whitening”) too much signal.
Transvaginal ultrasound showing a sagittal view of the uterus

Transvaginal ultrasound Transvaginal Ultrasound Obstetric Imaging showing a sagittal Sagittal Computed Tomography (CT) view of the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy:
The majority of the structure represents normal and homogenous myometrium. The endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development is the more hyperechoic Hyperechoic A structure that produces a high-amplitude echo (lighter grays and white) Ultrasound (Sonography) (lighter) strip down the middle. Endometrial thickness is measured near the fundus Fundus The superior portion of the body of the stomach above the level of the cardiac notch. Stomach: Anatomy and is noted to be 7.1 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma, which is normal in reproductive-aged women.

Image: “Transvaginal ultrasonography after an episode of heavy bleeding in a 24 year old woman” by Mikael Häggström. License: CC0 1.0

Advanced modalities and techniques

Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) ultrasound:

  • Used to assess blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure:
    • To ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy during evaluation of ovarian torsion Ovarian torsion Ovarian torsion is a clinical emergency in which the ovaries (with or without the fallopian tubes) twist along their axis, leading to partial or complete obstruction of their blood supply. Ovarian torsion is also called adnexal or tubo-ovarian torsion, especially if a fallopian tube is also involved. Ovarian Torsion
    • To an adnexal mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast, when evaluating for an ectopic pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care and/or neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors
    • Of the fetal cardiovascular system and to the uteroplacenta
  • Flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure is often shown as:
    • A continuous waveform
    • Color mapping, overlying standard ultrasound images

Saline infusion sonogram Sonogram Chorioretinitis ( SIS SIS Infertility) (sometimes called a sonohysterogram):

  • Positioning: dorsal lithotomy
  • A catheter is placed into the endometrial cavity.
  • A TVUS probe Probe A device placed on the patient’s body to visualize a target Ultrasound (Sonography) is inserted into the vagina Vagina The vagina is the female genital canal, extending from the vulva externally to the cervix uteri internally. The structures have sexual, reproductive, and urinary functions and a rich blood supply, mainly arising from the internal iliac artery. Vagina, Vulva, and Pelvic Floor: Anatomy.
  • While observing TVUS in real time, sterile Sterile Basic Procedures saline is injected into the endometrial cavity:
    • Saline distends the cavity, allowing for the evaluation of intracavitary lesions.
    • Although the fluid effluxes through the fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy, the tubes are too thin for observation of the flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure on TVUS.

3-dimensional (3D) sonography Sonography The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1. 6 to 10 megahertz. Diagnostic Procedures in Gynecology:

Saline infusion sonogram (sis)

Saline infusion sonogram Sonogram Chorioretinitis ( SIS SIS Infertility):
Sterile Sterile Basic Procedures saline instilled into the uterine cavity is anechoic Anechoic A structure that produces no echo at all (looks completely black) Ultrasound (Sonography) (visible as the dark central portion of the image); it delineates the shape of the endometrial cavity. This image shows a normal endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development ( hyperechoic Hyperechoic A structure that produces a high-amplitude echo (lighter grays and white) Ultrasound (Sonography)/brighter band around the cavity) without any focal changes. The endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development is surrounded by the myometrium that stretches almost to the right border of the image.

Image: “Normal hysterosonography” by Mikael Häggström. License: CC0 1.0

Interpretation and evaluation

  • Structures are evaluated in both the sagittal Sagittal Computed Tomography (CT) and transverse planes.
  • Size measurements to obtain:
    • Uterine size in all 3 planes (longitudinal, transverse, anterior/posterior)
    • Endometrial thickness (varies with menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle status)
    • Cervical length
    • Ovarian size in all 3 planes and calculation of overall volume
  • Note uterine position: e.g., anteflexed, anteverted, mid position, retroverted, or retroflexed
  • Note any free fluid in the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy (small, moderate, significant).
  • Note:
    • Fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy are not visible on ultrasound if normal (though fallopian tube Fallopian Tube A pair of highly specialized canals extending from the uterus to its corresponding ovary. They provide the means for ovum transport from the ovaries and they are the site of the ovum’s final maturation and fertilization. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells. Uterus, Cervix, and Fallopian Tubes: Anatomy masses are).
    • Ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy are often not visible on ultrasound if normal in a postmenopausal woman (too small to definitely find them).
  • Note any lesions or abnormalities including:
    • Masses
    • Fluid collection
    • Abnormal echogenicity
    • Structural anomalies

Magnetic Resonance Imaging

Indications

Although pelvic MRI is rarely a 1st-line test, it is typically ordered for better visualization of abnormalities that are identified on ultrasound. Some reasons to order a pelvic MRI include:

  • Differentiation between benign Benign Fibroadenoma and malignant lesions, for example:
    • Leiomyoma Leiomyoma A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the uterus and the gastrointestinal tract but can occur in the skin and subcutaneous tissue, probably arising from the smooth muscle of small blood vessels in these tissues. Infertility ( benign Benign Fibroadenoma fibroids Fibroids A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the uterus and the gastrointestinal tract but can occur in the skin and subcutaneous tissue, probably arising from the smooth muscle of small blood vessels in these tissues. Infertility) versus leiomyosarcoma Leiomyosarcoma Uterine leiomyomas (or uterine fibroids) are benign tumors arising from smooth muscle cells in the uterine myometrium. Leiomyosarcomas, however, are malignant tumors, arising de novo (not from fibroids). Uterine Leiomyoma and Leiomyosarcoma
    • Ovarian cystadenomas versus cystadenocarcinomas
  • Better characterization of CUAs
  • Other indeterminate lesions noted incidentally on ultrasound and CT
  • Assists in preoperative planning (e.g., hysterectomy)

Advantages

  • Provides better detail of soft tissue Soft Tissue Soft Tissue Abscess in particular (e.g., can identify fat in an adnexal mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast suggesting a dermoid cyst)
  • No radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma
  • Can be used to evaluate conditions in women who are pregnant

Disadvantages

  • ↑ Cost
  • Takes much longer to perform than ultrasound (or CT)
  • Less readily available
  • Not suitable for all cases:
    • Implants (particularly metal) distort image.
    • Requires the subject to be an enclosed space that is loud
    • The subject must stay still for adequate image acquisition.

Positioning

  • Supine on the table
  • Table is advanced into the scanner.
  • The subject is instructed to remain still for the scan.

Types of images

Table: Tissue characteristics of T1- versus T2-weighted MRI
Tissue T1-weighted images T1-Weighted Images Imaging of the Head and Brain T2-weighted images T2-Weighted Images Imaging of the Head and Brain
Fluid Dark Bright
Fat Bright Bright
Inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation Dark Bright

Interpretation and evaluation

Interpretation should follow a systematic and reproducible pattern:

  • Observe for “continuity” of structures while scrolling through image slices.
  • Identical to ultrasound evaluation:
    • Standard measurements
    • Uterine orientation Orientation Awareness of oneself in relation to time, place and person. Psychiatric Assessment
    • Comment on free fluid in the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy.
    • Note any lesions or abnormalities.

Normal Findings on Ultrasound and MRI

  • Size (normal uterus does not have distinct cutoff values):
    • Approximate uterine size in a reproductive-aged woman: 8 cm x 4 cm x 4 cm + 1 cm in any direction
    • Smaller in postmenopausal women
  • Shape: normal contour (inverted pear shape with a smooth fundal curvature)
  • Myometrium: homogenous
  • Endometrial thickness:
    • Appearance:
      • On ultrasound: a thin hyperechoic Hyperechoic A structure that produces a high-amplitude echo (lighter grays and white) Ultrasound (Sonography) line within the myometrium
      • On MRI: appears similar to fluid → darker on T1, brighter on T2
    • During menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle: 2‒20 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma depending on the timing during the menstrual cycle Cycle The type of signal that ends the inspiratory phase delivered by the ventilator Invasive Mechanical Ventilation
    • Postmenopausal women: ≤ 4 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma
      • Without bleeding
      • Slightly thicker endometria may still be normal.
      • If ≥ 5 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma with postmenopausal bleeding → endometrial biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma is required to rule out neoplasia
  • Ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy:
    • Approximately 4 cm x 2 cm x 1 cm during reproductive years
    • Volume < 10 mL
    • Will typically have follicles (small cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change) during reproductive years
    • On ultrasound: symmetric, bilateral, normal Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure
  • Fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy: not visualized if normal
  • Free fluid: small amount of simple hypoechoic Hypoechoic A structure that produces a low-amplitude echo (darker grays) Ultrasound (Sonography) fluid in the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy (difficult to measure definitively)

Abnormal and Other Incidental Findings on Ultrasound and MRI

Simple and/or follicular cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change

Table: Additional imaging findings suggestive of simple/follicular cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change
Ultrasound characteristics MRI characteristics
  • Anechoic Anechoic A structure that produces no echo at all (looks completely black) Ultrasound (Sonography)
  • No increased vascular flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure on Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography)
  • Surrounded by normal ovarian tissue
  • Homogeneous Homogeneous Imaging of the Spleen
  • T1: low signal intensity (dark)
  • T2: very high signal intensity (bright)
  • Post contrast: thin and featureless wall enhancement

Corpus luteal cyst Corpus luteal cyst Following ovulation, follicles become corpus luteal cysts. Secrete progesterone Ovarian Cysts

  • A corpus luteum is the “empty follicle” after ovulation Ovulation The discharge of an ovum from a rupturing follicle in the ovary. Menstrual Cycle.
  • Produces the progesterone Progesterone The major progestational steroid that is secreted primarily by the corpus luteum and the placenta. Progesterone acts on the uterus, the mammary glands and the brain. It is required in embryo implantation; pregnancy maintenance, and the development of mammary tissue for milk production. Progesterone, converted from pregnenolone, also serves as an intermediate in the biosynthesis of gonadal steroid hormones and adrenal corticosteroids. Gonadal Hormones required to sustain an early pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care
  • Normal finding during the 2nd ½ of the menstrual cycle Cycle The type of signal that ends the inspiratory phase delivered by the ventilator Invasive Mechanical Ventilation in ovulatory women
Table: Imaging findings suggestive of corpus luteal cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change
Ultrasound characteristics MRI characteristics
  • Thick rim
  • Usually measures up to 3 cm in size (although can reach sizes up to 15 cm)
  • Peripheral flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure on color Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) (“ring of fire”)
  • Small central lucency with internal echoes
Ultrasound image of a corpus luteum cyst with thick walls and peripheral color flow on doppler

Ultrasound image of a corpus luteum Corpus Luteum The yellow body derived from the ruptured ovarian follicle after ovulation. The process of corpus luteum formation, luteinization, is regulated by luteinizing hormone. Ovaries: Anatomy cyst with thick walls and peripheral color flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure on Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography)

Image by Hetal Verma, MD.

Hemorrhagic cyst

  • Bleeding into follicular or corpus luteal cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change
  • Resolves spontaneously in 1‒2 menstrual cycles
Table: Imaging findings suggestive of hemorrhagic cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change
Ultrasound characteristics MRI characteristics
  • T1: isointense to hyperintense Hyperintense Magnetic Resonance Imaging (MRI) (medium to bright)
  • T2: hyperintense Hyperintense Magnetic Resonance Imaging (MRI) (bright)
  • Weak or no enhancement with contrast
  • Highly variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables based on the timing away from an inciting hemorrhagic event

Endometrioma Endometrioma Endometriosis

An endometrioma Endometrioma Endometriosis is a collection of endometrial tissue Endometrial tissue The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Endometriosis on the ovary.

  • Type of endometriosis Endometriosis Endometriosis is a common disease in which patients have endometrial tissue implanted outside of the uterus. Endometrial implants can occur anywhere in the pelvis, including the ovaries, the broad and uterosacral ligaments, the pelvic peritoneum, and the urinary and gastrointestinal tracts. Endometriosis
  • Unlike hemorrhagic cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change, endometriomas will not resolve spontaneously in 1‒2 menstrual cycles.
Table: Imaging findings suggestive of endometriomas
Ultrasound characteristics MRI characteristics
  • Low-level internal echoes often with a ground-glass appearance
  • With/without septations
  • Poorly vascularized
  • Very similar in appearance to a newly formed hemorrhagic cyst
Table: MRI findings differentiating an endometrioma Endometrioma Endometriosis from a hemorrhagic cyst
Hemorrhagic cyst Endometrioma Endometrioma Endometriosis
T1 Bright Bright
T2 Bright Dark
Resolution Within 1–2 menstrual cycles → disappears on follow-up scan Does not resolve spontaneously → persists on follow-up scan

Dermoid cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change (mature cystic Cystic Fibrocystic Change teratomas Teratomas A true neoplasm composed of a number of different types of tissue, none of which is native to the area in which it occurs. It is composed of tissues that are derived from three germinal layers, the endoderm, mesoderm, and ectoderm. They are classified histologically as mature (benign) or immature (malignant). Ovarian Cancer)

  • A type of benign Benign Fibroadenoma germ cell tumor Tumor Inflammation consisting of tissue from all 3 germ layers
  • Frequently contains fat, which is unusual in other types of masses (helps identification Identification Defense Mechanisms on MRI)
  • Heterogenous on imaging
  • With/without calcifications ( teeth Teeth Normally, an adult has 32 teeth: 16 maxillary and 16 mandibular. These teeth are divided into 4 quadrants with 8 teeth each. Each quadrant consists of 2 incisors (dentes incisivi), 1 canine (dens caninus), 2 premolars (dentes premolares), and 3 molars (dentes molares). Teeth are composed of enamel, dentin, and dental cement. Teeth: Anatomy)
  • Can be lopsided in nature → ↑ risk of ovarian torsion Ovarian torsion Ovarian torsion is a clinical emergency in which the ovaries (with or without the fallopian tubes) twist along their axis, leading to partial or complete obstruction of their blood supply. Ovarian torsion is also called adnexal or tubo-ovarian torsion, especially if a fallopian tube is also involved. Ovarian Torsion
Table: Imaging findings suggestive of dermoid cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change
Ultrasound characteristics MRI characteristics

Other ovarian neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors

Ovarian neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors: benign Benign Fibroadenoma (noninvasive) or malignant (invasive) growths arising from a single cell. Ovarian neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors are classified according to their cell of origin as either epithelial, germ cell, or stromal tumors (with many different subtypes in each class). Concerning imaging findings include:

  • Multinodular heterogeneous tumors
  • Presence of papillary projections into a cyst
  • Solid component(s)
  • Thick, irregular walls
  • Septations
  • Vascular flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure within septations
  • Presence of ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites
  • Potentially seen in cases with metastasis Metastasis The transfer of a neoplasm from one organ or part of the body to another remote from the primary site. Grading, Staging, and Metastasis:
    • Lymphadenopathy Lymphadenopathy Lymphadenopathy is lymph node enlargement (> 1 cm) and is benign and self-limited in most patients. Etiologies include malignancy, infection, and autoimmune disorders, as well as iatrogenic causes such as the use of certain medications. Generalized lymphadenopathy often indicates underlying systemic disease. Lymphadenopathy
    • Peritoneal and/or omental nodularity

Ovarian torsion Ovarian torsion Ovarian torsion is a clinical emergency in which the ovaries (with or without the fallopian tubes) twist along their axis, leading to partial or complete obstruction of their blood supply. Ovarian torsion is also called adnexal or tubo-ovarian torsion, especially if a fallopian tube is also involved. Ovarian Torsion

Ovarian torsion Ovarian torsion Ovarian torsion is a clinical emergency in which the ovaries (with or without the fallopian tubes) twist along their axis, leading to partial or complete obstruction of their blood supply. Ovarian torsion is also called adnexal or tubo-ovarian torsion, especially if a fallopian tube is also involved. Ovarian Torsion refers to the acute twisting of the ovary around its blood supply. Ovarian torsion Ovarian torsion Ovarian torsion is a clinical emergency in which the ovaries (with or without the fallopian tubes) twist along their axis, leading to partial or complete obstruction of their blood supply. Ovarian torsion is also called adnexal or tubo-ovarian torsion, especially if a fallopian tube is also involved. Ovarian Torsion presents with acute pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and is considered a surgical emergency Surgical Emergency Acute Abdomen (to untwist/save the ovary). Evaluation is usually only with ultrasound.

  • Usually associated with an ovarian mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast (commonly dermoids due to their lopsided nature)
  • Enlarged heterogenous ovary (often > 4 cm)
  • Free pelvic fluid
  • With/without Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure (since torsion can be transient), but absence of flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure confirms torsion/indicates infarction
  • Frequently appears as normal

Ectopic pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care

An ectopic pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care is a pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care outside the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy. A rupture can result in life-threatening hemorrhage. An ectopic pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care is almost always evaluated using ultrasound only.

  • Complex heterogenous extraovarian mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast with/without Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure (most common finding on ultrasound)
  • Presence of a gestational sac with/without a yolk sac Yolk Sac The first of four extra-embryonic membranes to form during embryogenesis. In reptiles and birds, it arises from endoderm and mesoderm to incorporate the egg yolk into the digestive tract for nourishing the embryo. In placental mammals, its nutritional function is vestigial; however, it is the source of intestinal mucosa; blood cells; and germ cells. It is sometimes called the vitelline sac, which should not be confused with the vitelline membrane of the egg. Embryoblast and Trophoblast Development and/or embryo Embryo The entity of a developing mammal, generally from the cleavage of a zygote to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the fetus. Fertilization and First Week outside the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy (less common)
  • Positive pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care test with the absence of a uterine pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care

Hydrosalpinx

A hydrosalpinx describes the condition of postinflammatory fluid filling the fallopian tube Fallopian Tube A pair of highly specialized canals extending from the uterus to its corresponding ovary. They provide the means for ovum transport from the ovaries and they are the site of the ovum’s final maturation and fertilization. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells. Uterus, Cervix, and Fallopian Tubes: Anatomy.

  • Tubular hypoechoic extraovarian structure
  • May appear to have “septations” (actually due to folds of the wall)

Uterine fibroids Fibroids A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the uterus and the gastrointestinal tract but can occur in the skin and subcutaneous tissue, probably arising from the smooth muscle of small blood vessels in these tissues. Infertility

Uterine fibroids Fibroids A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the uterus and the gastrointestinal tract but can occur in the skin and subcutaneous tissue, probably arising from the smooth muscle of small blood vessels in these tissues. Infertility (or leiomyomas) are benign Benign Fibroadenoma uterine neoplasms Neoplasms New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms. Benign Bone Tumors arising from a single myometrial cell:

  • Round or oval mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast arising from the myometrium
  • Encapsulated Encapsulated Klebsiella → well-defined margins on both ultrasound and MRI
  • Usually homogenous
  • May be heterogenous if degenerating
  • Can be located anywhere in the myometrium, and are classified by location:
    • Submucosal: protruding into the endometrial cavity
    • Intramural: within the myometrium
    • Subserosal: protruding outside the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy, covered by serosa
Table: Imaging findings suggestive of uterine fibroids Fibroids A benign tumor derived from smooth muscle tissue, also known as a fibroid tumor. They rarely occur outside of the uterus and the gastrointestinal tract but can occur in the skin and subcutaneous tissue, probably arising from the smooth muscle of small blood vessels in these tissues. Infertility (leiomyomas)
Ultrasound characteristics MRI characteristics
  • T1: darker normal myometrium
  • T2: dark
  • Variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables enhancement (post-contrast administration)

Adenomyosis Adenomyosis Adenomyosis is a benign uterine condition characterized by the presence of ectopic endometrial glands and stroma within the myometrium. Adenomyosis is a common condition, affecting 20%-35% of women, and typically presents with heavy menstrual bleeding and dysmenorrhea. Adenomyosis

Adenomyosis Adenomyosis Adenomyosis is a benign uterine condition characterized by the presence of ectopic endometrial glands and stroma within the myometrium. Adenomyosis is a common condition, affecting 20%-35% of women, and typically presents with heavy menstrual bleeding and dysmenorrhea. Adenomyosis is a clinical condition in which the endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development implants/invades into the myometrium, typically resulting in heavy, painful menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle. Findings on both ultrasound and MRI include:

  • Enlarged uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy
  • Myometrial cystic Cystic Fibrocystic Change spaces
  • Enlarged and globular uterine appearance
  • Asymmetrical thickening of the myometrium (especially a thickened posterior wall)
  • Loss of a clear endomyometrial border/thickening of the junctional zone

Endometrial polyps Endometrial polyps Endometrial polyps are pedunculated or sessile projections of the endometrium that result from overgrowth of endometrial glands and stroma around a central vascular stalk. Endometrial polyps are a few millimeters to a few centimeters in size, can occur anywhere within the uterine cavity, and, while usually benign, can be malignant, particularly in postmenopausal women. Endometrial Polyps

A small growth off the endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development that is usually pedunculated and often (though not always) benign Benign Fibroadenoma:

  • Thickened endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development on regular Regular Insulin TVUS/TAUS and MRI
  • Mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast arising from the endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development and protruding into uterine cavity on SIS SIS Infertility (best test to visualize polyps)
A pedunculated endometrial polyp seen on saline infusion sonogram (sis)

A pedunculated endometrial polyp seen on a saline infusion sonogram Sonogram Chorioretinitis ( SIS SIS Infertility)

Image: “3D-MS- View of endometrial outline in the transverse plane Transverse plane Anterior Abdominal Wall: Anatomy shows a localized lesion” by Zafarani F., Ahmadi F. License: CC BY 2.5, cropped by Lecturio.

Endometrial hyperplasia Endometrial Hyperplasia Benign proliferation of the endometrium in the uterus. Endometrial hyperplasia is classified by its cytology and glandular tissue. There are simple, complex (adenomatous without atypia), and atypical hyperplasia representing also the ascending risk of becoming malignant. Endometrial Hyperplasia and Endometrial Cancer and cancer

  • Thickened endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development based on age and/or menstrual status
  • Heterogeneous echogenicity 
  • Features suggestive of cancer:
    • Irregular and/or indistinct borders
    • Frank invasion
    • Thickness > 5 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma in postmenopausal women
Endometrial thickening consistent with endometrial hyperplasia

Endometrial thickening consistent with endometrial hyperplasia Endometrial Hyperplasia Benign proliferation of the endometrium in the uterus. Endometrial hyperplasia is classified by its cytology and glandular tissue. There are simple, complex (adenomatous without atypia), and atypical hyperplasia representing also the ascending risk of becoming malignant. Endometrial Hyperplasia and Endometrial Cancer

Image: “Glandular cystic Cystic Fibrocystic Change hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation that is softer than the myometrium on SEG.E endometrium Endometrium The mucous membrane lining of the uterine cavity that is hormonally responsive during the menstrual cycle and pregnancy. The endometrium undergoes cyclic changes that characterize menstruation. After successful fertilization, it serves to sustain the developing embryo. Embryoblast and Trophoblast Development” by Goncharenko V. M. et al AL Amyloidosis. License: CC BY 2.0, edited by Lecturio.

Hysterosalpingography

Description

  • Fluoroscopic examination that allows assessment of:
    • Uterine cavity shape
    • Patency of fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy (best nonsurgical test available)
  • A catheter is inserted into the uterine cavity → dye is injected → X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests

Indications

  • Evaluation of CUAs
  • Infertility Infertility Infertility is the inability to conceive in the context of regular intercourse. The most common causes of infertility in women are related to ovulatory dysfunction or tubal obstruction, whereas, in men, abnormal sperm is a common cause. Infertility (to look for congenital Congenital Chorioretinitis anomalies and check tubal patency)

Contraindications Contraindications A condition or factor associated with a recipient that makes the use of a drug, procedure, or physical agent improper or inadvisable. Contraindications may be absolute (life threatening) or relative (higher risk of complications in which benefits may outweigh risks). Noninvasive Ventilation

  • Pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care
  • Active undiagnosed vaginal bleeding
  • Active pelvic infection

Advantages

  • Relatively low cost 
  • Lower radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma dose (although can become high with prolonged study time)
  • Relatively ubiquitous availability
  • Dynamic imaging

Disadvantages

  • Poor resolution of soft tissue Soft Tissue Soft Tissue Abscess
  • Exposure Exposure ABCDE Assessment to ionizing radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma
  • Discomfort/ pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways to the subject
  • Complicated scheduling:
    • Should be performed between the end of menstruation Menstruation The periodic shedding of the endometrium and associated menstrual bleeding in the menstrual cycle of humans and primates. Menstruation is due to the decline in circulating progesterone, and occurs at the late luteal phase when luteolysis of the corpus luteum takes place. Menstrual Cycle and prior to ovulation Ovulation The discharge of an ovum from a rupturing follicle in the ovary. Menstrual Cycle (to avoid interruption of an early pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care)
    • Often requires both a gynecologist (to place the catheter) and radiologist (to interpret images) present in the room during the study

Exam technique

  • Positioning:
    • Dorsal lithotomy on the fluoroscopy Fluoroscopy Production of an image when x-rays strike a fluorescent screen. X-rays table
    • Board is placed against the back.
    • X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests beams from the floor → ceiling direction through the subject
  • Visualization: Field of view should be focused on the pelvis Pelvis The pelvis consists of the bony pelvic girdle, the muscular and ligamentous pelvic floor, and the pelvic cavity, which contains viscera, vessels, and multiple nerves and muscles. The pelvic girdle, composed of 2 “hip” bones and the sacrum, is a ring-like bony structure of the axial skeleton that links the vertebral column with the lower extremities. Pelvis: Anatomy.
  • Procedure:
    • A speculum is inserted into the vagina Vagina The vagina is the female genital canal, extending from the vulva externally to the cervix uteri internally. The structures have sexual, reproductive, and urinary functions and a rich blood supply, mainly arising from the internal iliac artery. Vagina, Vulva, and Pelvic Floor: Anatomy and the cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy is identified.
    • A balloon-tipped catheter is inserted through the cervical canal Cervical canal Uterus, Cervix, and Fallopian Tubes: Anatomy into the uterine cavity.
    • Contrast is injected slowly and observed in fluoroscopy Fluoroscopy Production of an image when x-rays strike a fluorescent screen. X-rays in real time.
    • Images are acquired.

Interpretation and evaluation

Systematic approach:

  • Inside-out approach Inside-Out Approach Imaging of the Lungs and Pleura (central to peripheral):
    • Look at the bowel-gas pattern.
    • Look for solid organ silhouettes Solid Organ Silhouettes Imaging of the Urinary System if in the field of view ( liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy, spleen Spleen The spleen is the largest lymphoid organ in the body, located in the LUQ of the abdomen, superior to the left kidney and posterior to the stomach at the level of the 9th-11th ribs just below the diaphragm. The spleen is highly vascular and acts as an important blood filter, cleansing the blood of pathogens and damaged erythrocytes. Spleen: Anatomy, kidney).
    • Look for normal fat planes peripherally.
    • Look for evidence of free intraperitoneal Intraperitoneal Peritoneum: Anatomy air.
    • Evaluate soft tissues for:
      • Contour of the uterine cavity
      • Patency of fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy
      • Abnormal calcifications (stones, masses)
    • Evaluate osseous structures ( vertebral body Vertebral body Main portion of the vertebra which bears majority of the weight. Vertebral Column: Anatomy height, iliac bones, femurs).
  • Dynamic approach:
    • Observe the flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure of contrast through the endometrial canal and note any:
    • Contrast should flow Flow Blood flows through the heart, arteries, capillaries, and veins in a closed, continuous circuit. Flow is the movement of volume per unit of time. Flow is affected by the pressure gradient and the resistance fluid encounters between 2 points. Vascular resistance is the opposition to flow, which is caused primarily by blood friction against vessel walls. Vascular Resistance, Flow, and Mean Arterial Pressure through the fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy and into the adnexal spaces.

Normal findings

  • Normal contour of the uterine cavity:
    • Upside-down triangle
    • No filling defects
  • Fallopian tubes fill with dye → dye spills out of the ends of both tubes into the pelvic cavity (“bilateral fill and spill”)
Normal hsg examination

Normal hysterosalpingography Hysterosalpingography Radiography of the uterus and fallopian tubes after the injection of a contrast medium. Congenital Malformations of the Female Reproductive System findings:
Radiograph showing normal uterine contour with bilateral fill and spill of dye from the fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy

Image: “Normal HSG examination” by Aziz M.U. et al AL Amyloidosis. License: CC BY 3.0

Abnormal or incidental findings

Hydrosalpinx:

  • Dilated tubes with collection of contrast in the tubes
  • With/without obstruction (i.e., no free spillage)
Hsg showing bilateral tubal blockage

Hysterosalpingogram Hysterosalpingogram Infertility showing bilateral tubal occlusion and hydrosalpinges Hydrosalpinges Infertility

Image: “HSG showing bilateral tubal blockage” by Aziz M.U. et al AL Amyloidosis. License: CC BY 3.0

CUAs:

The uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy forms from the Müllerian ducts, which fuse in the midline to create the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy, cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy, and upper vagina Vagina The vagina is the female genital canal, extending from the vulva externally to the cervix uteri internally. The structures have sexual, reproductive, and urinary functions and a rich blood supply, mainly arising from the internal iliac artery. Vagina, Vulva, and Pelvic Floor: Anatomy. Therefore, initially, these structures are divided down the midline before the midline septum regresses. Congenital Congenital Chorioretinitis uterine abnormalities typically occur due to abnormal fusion and/or septal regression Regression Corneal Abrasions, Erosion, and Ulcers.

  • Septate uterus:
    • Filling defect starting from the uterine apex
    • Length of the septum varies.
  • Bicornuate uterus:
    • Filling defect starting from the uterine apex
    • 2 banana-shaped cavities, each draining into a normal fallopian tube
  • Unicornuate uterus: single fusiform uterine cavity draining into a single tube
  • Uterus didelphys: 2 completely separate “systems”
    • 2 uterine cavities, each with their own cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy and fallopian tube Fallopian Tube A pair of highly specialized canals extending from the uterus to its corresponding ovary. They provide the means for ovum transport from the ovaries and they are the site of the ovum’s final maturation and fertilization. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells. Uterus, Cervix, and Fallopian Tubes: Anatomy
    • No communication Communication The exchange or transmission of ideas, attitudes, or beliefs between individuals or groups. Decision-making Capacity and Legal Competence between sides

Related videos

References

  1. Stewart, E.A. (2021). Uterine adenomyosis. In A. Chakrabarti, A. (Ed.), UpToDate. Retrieved March 3, 2021, from https://www.uptodate.com/contents/uterine-adenomyosis 
  2. Gunther, R. (2020). Adenomyosis. In Walker, C. (Ed.), StatPearls. Retrieved March 3, 2021, from https://www.statpearls.com/articlelibrary/viewarticle/42961/ 
  3. Schenken, R.S. (2020). Endometriosis: Pathogenesis, clinical features, and diagnosis. In Eckler, K. (Ed.), UpToDate. Retrieved January 28, 2021, from https://www.uptodate.com/contents/endometriosis-pathogenesis-clinical-features-and-diagnosis
  4. Schenken, R.S. (2020). Endometriosis: Treatment of pelvic pain. In Eckler, K. (Ed.), UpToDate. Retrieved January 28, 2021, from https://www.uptodate.com/contents/endometriosis-treatment-of-pelvic-pain

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