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Pseudodysraphism

A pseudodysraphism refers to the splayed appearance of a normal spine created due to excessive craniocaudal angulation during sonographic evaluation. This can erroneously lead to the diagnosis of a spinal neural tube defect.

Pelvic congestion syndrome

Pelvic congestion syndrome (some prefer pelvic venous insufficiency 9) is a condition that results from retrograde flow through incompetent valves in ovarian veins. It is a commonly missed and potentially-treatable cause of chronic abdominopelvic pain. Epidemiology It tends to be more common ...

Semilobar holoprosencephaly

Semilobar holoprosencephaly is a subtype of holoprosencephaly characterized by incomplete forebrain division. It is intermediate in severity, being worse than lobar holoprosencephaly and better than alobar holoprosencephaly. Epidemiology Please refer to the general article of holoprosencephaly...

Müllerian duct anomalies

Müllerian duct anomalies (MDAs) are congenital abnormalities that occur when the Müllerian ducts (paramesonephric ducts) do not develop correctly. This may be as a result of complete agenesis, defective vertical or lateral fusion, or resorption failure. Epidemiology MDAs are estimated to occur...

Müllerian duct

The Müllerian ducts (or paramesonephric ducts) are paired ducts of mesodermal origin in the embryo. They run laterally down the side of the urogenital ridge and terminate at the Müllerian eminence in the primitive urogenital sinus. In the female, they will develop to form the uterine tubes, ute...

Unicornuate uterus

A unicornuate uterus or unicornis unicollis is a type of Müllerian duct anomaly (class II) characterized by a banana-shaped uterus usually draining into a single fallopian tube. Epidemiology This type can account for ~10% (range 6-13%) of uterine anomalies and infertility is seen in ~12.5% (ra...

Arcuate uterus

An arcuate uterus is a mildly variant shape of the uterus. It is technically one of the Müllerian duct anomalies, but is often classified as a normal variant. It is the uterine anomaly that is least commonly associated with reproductive failure. Arcuate uterus can be characterized with ultrasoun...

Septate uterus

A septate uterus is the most common type of congenital uterine anomaly, and may lead to an increased rate of pregnancy loss. The main imaging differential diagnoses are arcuate uterus and bicornuate uterus. Epidemiology It is considered the most common uterine anomaly (accounts for ~55% of suc...

Abscess

Abscesses are focal confined collections of suppurative inflammatory material and can be thought of as having three components 1: a central core consisting of necrotic inflammatory cells and local tissue peripheral halo of viable neutrophils surrounded by a 'capsule' with dilated blood...

Shading sign (endometrioma)

Shading sign is an MRI finding typically seen in an endometrioma. It may also be seen with some endometrioid tumors (e.g. endometrioid carcinoma of the ovary) and uncommonly other blood-containing lesions (e.g. hemorrhagic corpus luteum cysts). The sign is seen on T2-weighted sequences of lesio...

Pelvic protocol for endometriosis (MRI)

Evaluation of known endometriosis with MRI requires a slightly different protocol to a routine pelvic MRI (see pelvic MRI protocol: routine), and should probably be reserved for known cases of endometriosis rather than for the assessment of pelvic pain. IV (or IM) Buscopan® is administered to r...

Endometriosis

Endometriosis is a common, chronic gynecological condition defined as the presence of functional endometrial glands and stroma-like lesions outside the uterus. It manifests in three ways: superficial (peritoneal) disease, ovarian disease (endometriomas), and deep endometriosis. Endometriosis is...

Funneling of the internal cervical os

Cervical funnelling is a sign of cervical incompetence and represents the dilatation of the internal part of the cervical canal and reduction of the cervical length. Greater than 50% funnelling before 25 weeks is associated with ~80% risk of preterm delivery. Radiographic features Good scanni...

Müllerian duct anomaly classification

The Müllerian duct anomaly classification is a seven-class system that can be used to describe a number of embryonic Müllerian duct anomalies: class I: uterine agenesis/uterine hypoplasia a: vaginal (uterus: normal/variety of abnormal forms) b: cervical c: fundal d: tub...

Popcorn calcification (disambiguation)

Popcorn calcification refers to amorphous calcifications often with rings and arcs that resemble popped corn kernels. This type of calcification may be seen in many radiological settings including 1: chondroid lesions (e.g. enchondroma, chondrosarcoma) fibrous dysplasia pulmonary hamartomas ...

Abdominal surface anatomy

Abdominal surface anatomy can be described when viewed from in front of the abdomen in 2 ways: divided into 9 regions by two vertical and two horizontal imaginary planes divided into 4 quadrants by single vertical and horizontal imaginary planes These regions and quadrants are of clinical imp...

Ileal atresia

Ileal atresia is a congenital abnormality where there is significant stenosis or complete absence of a portion of the ileum. There is an increased incidence in those with chromosomal abnormalities. This article will focus on ileal atresia alone but bear in mind that some cases correspond to jej...

Ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) is a complication of controlled ovarian stimulation, which is an assisted reproduction technique used for in vitro fertilisation (IVF). Rarely, it may also occur spontaneously in pregnancy (see below). It consists of ovarian enlargement with an extravascu...

Ovarian tumors

Ovarian tumors are relatively common and account for ~6% of female malignancies. This article focuses on the general classification of ovarian tumors. For specific tumor features, please refer to the relevant subarticles. Pathology Subtypes Primary ovarian tumors Surface epithelial-stromal o...

Ovarian artery

The ovarian artery is a paired structure and is the main gonadal artery in females. Gross anatomy Origin The ovarian artery arises anterolaterally from the aorta just inferior to the renal arteries and superior to the inferior mesenteric artery (between L2 and L3). Course Descends caudally ...

Uterine artery

The uterine artery is seen bilaterally and is a branch of the anterior division of the internal iliac artery. Gross anatomy Course It runs medially in the pelvis, within the base of the broad ligament, to the outer surface of the uterus. From lateral to medial it has a descending, transverse ...

Pelvis

The term pelvis (plural: pelvises or pelves) can refer to either the bony pelvis or the pelvic cavity. Bony pelvis The bony pelvis is formed by the sacrum and coccyx and a pair of hip bones ("ossa coxae"), which are part of the appendicular skeleton. Its primary function is the transmission of...

Intrauterine contraceptive device

Intrauterine contraceptive devices (IUCD) (also known as intrauterine devices (IUD) and colloquially commonly as the coil) are one of the most frequently used methods of contraception throughout the world. It prevents pregnancy by: thinning the endometrial lining preventing sperm motility pre...

Vagina

The vagina is a midline fibromuscular tubular organ positioned in the female perineum extending superiorly from the vulva, to the cervix and uterus in the pelvis. Gross anatomy The vagina is 6-8 cm in length, extending posterosuperior from the vestibule through the urogenital diaphragm to the...

Polyhydramnios

Polyhydramnios refers to a situation where the amniotic fluid volume is more than expected for gestational age. It is generally defined as: amniotic fluid index (AFI) >25 cm largest fluid pocket depth (maximal vertical pocket (MVP)) greater than 8 cm 6 some centers, particularly in Australi...

Pelvic masses in females

Pelvic masses in females carry a broad differential diagnosis: benign adnexal cyst leiomyoma pelvic malignancy dermoid endometriosis pelvic inflammatory disease tubo-ovarian abscess hydrosalpinx pregnancy Extragynaecological masses, e.g. colorectal carcinoma, appendicular abscess, lymp...

Ovarian cyst

Ovarian cysts are commonly encountered in gynecological imaging and vary widely in etiology from physiological to complex benign to neoplastic. Pathology Small cystic ovarian structures should be considered normal ovarian follicles unless the patient is pre-pubertal, post-menopausal, pregnant,...

Polycystic ovarian syndrome

Polycystic ovarian syndrome (PCOS), recently referred also as hyperandrogenic anovulation, is a chronic anovulation syndrome associated with androgen excess. The Rotterdam criteria is used to make the diagnosis of PCOS and require any two of the following three criteria for the diagnosis, as w...

Uterus

The uterus is an extraperitoneal hollow, thick-walled, muscular organ of the female reproductive tract that lies in the lesser pelvis. Gross anatomy The uterus has an inverted pear shape. It measures about 7.5 cm in length, 5 cm wide at its upper part, and nearly 2.5 cm in thickness in adults....

Cervix

The cervix or uterine cervix is the lower constricted segment of the uterus providing the passage between the uterus proper and the vagina. Gross anatomy The cervix is somewhat conical in shape, with its truncated apex directed posteriorly and inferiorly. The inferior aspect of the cervix pro...

Ovary

The ovaries (TA: ovarium 9) are paired female gonads of the reproductive and endocrine systems. They lie within the ovarian fossa on the posterior wall of the true pelvis and form part of the adnexa. Gross anatomy The ovaries are firm and ovoid in shape and measure approximately 1.5-3.0 cm × ...

Vaginal pessary

A vaginal pessary is a device inserted into the vagina which can either be mechanical or pharmaceutical. Terminology Strictly speaking, a pessary only refers to a medical device designed to be placed in the vagina to support the pelvic floor. Therefore, stating vaginal pessary is tautologous, ...

VACTERL association

VACTERL is an acronym that describes a non-random constellation of congenital anomalies. It is not a true syndrome as such and is equivalent to the VATER anomaly. Epidemiology The estimated incidence is 1 in 10,000-40,000 births 3. Associations Several conditions have features in common with...

Uterus didelphys

Uterus didelphys is a type of Müllerian duct anomaly (class III) where there is a complete duplication of uterine horns as well as duplication of the cervix, with no communication between them. Epidemiology Didelphic uteri account for approximately ~8% (range 5-11%) of Müllerian duct anomali...

Turner syndrome

Turner syndrome, also known as 45XO or 45X, is the most common of the sex chromosome abnormalities in females. Epidemiology The incidence is estimated at 1:2000-5000 of live births, although the in utero rate is much higher (1-2% of conceptions) due to a significant proportion of fetuses with...

Tubal ectopic pregnancy

Tubal ectopic pregnancy (or adnexal ectopic pregnancy) is the most common location of an ectopic pregnancy. Epidemiology It is the most common type of ectopic by far, accounting for 93-97% of cases. Pathology Although the fallopian tube has many anatomical parts, for the purposes of ectopic ...

Tubal ring sign

Tubal ring sign also referred to as bagel sign or blob sign, one of the ultrasound signs of a tubal ectopic. It comprises an echogenic ring that surrounds an unruptured ectopic pregnancy. It is said to have a 95% positive predictive value (PPV) for ectopic pregnancy. Differential diagnosis It ...

String of pearls sign (disambiguation)

String of pearls sign can refer to: string of pearls sign on an abdominal radiograph of fluid-filled dilated small bowel loops string of pearls sign on cerebral MRI in deep border zone infarction string of pearls sign on ultrasound in polycystic ovarian syndrome string of pearls sign for ang...

Pyometrium

Pyometrium refers to infection of the endometrial cavity with resulting expansion due to accumulated pus (pyometra). The postmenopausal demographic are most commonly affected due to the association with uterine malignancy. Pathology Etiology endometritis / pelvic inflammatory disease uterin...

Psammoma bodies

Psammoma bodies are round microscopic calcific collections. It is a form of dystrophic calcification. Necrotic cells form the focus for surrounding calcific deposition. They have a lamellated concentric calcified structure, sometimes large enough to be seen on CT. Psammoma bodies are found in ...

Mature cystic ovarian teratoma

Ovarian dermoid cyst and mature cystic ovarian teratoma are terms often used interchangeably to refer to the most common ovarian neoplasm. These slow-growing tumors contain elements from multiple germ cell layers and can be assessed with ultrasound or MRI. Terminology Although they have very ...

Naegele's formula

The Naegele's formula is simple arithmetic method for calculating the EDD (estimated date of delivery) based on the LMP (last menstrual period). To the date of the first day of the LMP (e.g. 22nd June 2008): add seven days (i.e 29th) subtract 3 months (i.e March) add one year (i.e 2009)

Megalencephaly

Megalencephaly (MEG) is a disorder characterized by an abnormally large brain. It is primarily a proliferative disorder of embryonic origin. It may involve all or part of the cerebral hemispheres and can be bilateral or unilateral. It is often associated with polymicrogyria or agyria. Terminol...

Hydrometrocolpos

Hydrometrocolpos is characterized by an expanded fluid filled vaginal cavity with associated distention of the uterine cavity. It may present in infancy with a lower abdominal mass, or be delayed till menarche. Pathology Etiology imperforate hymen (most common) also involves the upper portion...

Hydrocolpos

Hydrocolpos is characterized by an expanded fluid-filled vaginal cavity. When it is associated with distention of the uterine cavity, the term hydrometrocolpos should then be used. It may present in neonate, infancy or in an adolescent girl with a lower abdominal mass, or be delayed till menarch...

Gestational trophoblastic disease

Gestational trophoblastic disease (GTD) results from the abnormal proliferation of trophoblastic tissue and encompasses a wide spectrum of diseases, including 14: tumor-like lesions exaggerated placental site reaction placental site nodule and plaque abnormal (non-molar) villo...

Germinoma

Germinoma is a term that if unqualified, usually refers to a tumor of the brain but can also refer to similar tumors of other regions particularly the ovary and testis. dysgerminoma of the ovary seminoma of the testis CNS germinoma: see WHO classification of CNS tumors All these tumors share...

Fallopian tube

The fallopian tube (TA: tuba uterina 8), also known as the uterine tube or less commonly the oviduct, is a paired hollow tube that bridges between each ovary and the uterus and functions to convey the mature ovum from the former to the latter. If conception occurs, it normally does so within the...

Endometrial carcinoma (staging)

Endometrial carcinoma staging allows appropriate treatment options to be considered and enables greater prognostic accuracy for endometrial carcinoma. Staging Staging can be based on the TNM or FIGO system. MR imaging is the modality of choice for staging with CT having relatively low speci...

Ectopic pregnancy

Ectopic pregnancy refers to the implantation of a fertilised ovum outside of the uterine cavity. Epidemiology The overall incidence has increased over the last few decades and is currently thought to affect 1-2% of pregnancies. The risk is as high as 18% for first trimester pregnancies with bl...

Cervical cancer (staging)

Staging of cervical cancer can either be based on the TNM or FIGO system. Classification Revised FIGO staging of cervical carcinoma (2018) FIGO no longer includes stage 0 (Tis) I: confined to cervix uteri (extension to the corpus should be disregarded) IA: invasive carcinoma only diagnosed ...

Bicornuate uterus

A bicornuate uterus is a type of uterine duplication anomaly. It can be classified as a class IV Mullerian duct anomaly. Epidemiology Overall, congenital uterine anomalies occur in ~1.5% of females (range 0.1-3%). Bicornuate uteri are thought to represent ~25% (range 10-39%) of Mullerian duct ...

Acute appendicitis

Acute appendicitis (plural: appendicitides) is an acute inflammation of the vermiform appendix. It is a very common condition in general radiology practice and is one of the main reasons for abdominal surgery in young patients. CT is the most sensitive modality to detect appendicitis. Terminolo...

Aggressive angiomyxoma

Aggressive angiomyxomas are rare tumors that arise in the pelvis and typically cross the levator ani muscles. Despite its name, it is essentially a benign tumor and the term "aggressive" is due to a predilection for local recurrence. Only rarely does it metastasize. Epidemiology It is seen pre...

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