The superficial perineal pouch is an anatomic space below the perineal membrane in the urogenital triangle of the perineum.
The superficial perineal pouch is inferior (superficial) to the perineal membrane in the urogenital triangle, anterior to the transverse line between the is...
Surgical hemostatic material is used to control bleeding intraoperatively and is hence frequently voluntarily left in the operative bed, not to be confused with a gossypiboma which is caused by foreign material left behind in error. It can mimic an abscess on imaging studies. Various types are a...
Syndactyly refers to a congenital fusion of two or more digits. It may be confined to soft tissue (soft tissue syndactyly / simple syndactyly) or may involve bone (bony syndactyly / complex syndactyly).
The overall estimated incidence is at ~1 per 2,500 to 5,000 live births 6,8. T...
T2 dark spot sign is an MRI appearance of endometriomas seen as a result of chronic hemorrhage. The sign is useful in differentiating a solitary endometrioma from a functional hemorrhagic ovarian cyst, as both might show high T1 signal with T2 shading.
The T2 dark spot, described in the sign, ...
Tamoxifen has pro-oestrogenic effects on the endometrium and thus is associated with an increased prevalence of:
endometrial polyps: occurs in ~8-36% of women in treated 8
endometrial hyperplasia: occurs in ~1-20% of women treated ref
cystic endometrial atrophy
Teratomas are germ cell tumors that arise from ectopic pluripotent stem cells that fail to migrate from yolk sac endoderm to the urogenital ridge during embryogenesis. By definition, they contain elements from all three embryological layers: endoderm, mesoderm and ectoderm although frequently, e...
Theca lutein cysts (TLC), also known as hyperreactio luteinalis (HL), are a type of functional ovarian cysts. They are typically multiple and seen bilaterally.
They are thought to originate due to excessive amounts of circulating gonadotrophins such as beta-hCG. Hyperplasia of the th...
Thoracic endometriosis is an uncommon location for endometriosis and the main cause of catamenial pneumothorax.
Most often occurs in the third and fourth decades of life 3.
Symptoms may include:
catamenial pleuritic chest pain
catamenial hemoptysis: when...
Tip of the iceberg sign refers to one of the characteristic appearances of an ovarian dermoid cyst. If there are echogenic cyst contents of sebum and hair, they cause marked posterior acoustic attenuation so that only the superficial part of the cyst is seen. Just like an iceberg, you may only b...
Trachelectomy (sometimes known as a cervicectomy) refers to the removal of the uterine cervix.
It is sometimes performed as a uterine-sparing surgery for certain cases with cervical malignancy 2-3. When it is performed with the curative intent it is often termed a radical trachelectomy and is ...
Transient abnormal myelopoiesis (TAM) is a phenomenon that can happen in the fetuses or neonates with trisomy 21. The condition can mimic leukemia.
The estimated incidence is at ~10% of newborns with trisomy 21 3.
In the context of kno...
Transient myometrial contraction is a physiological phenomenon which may mimic focal adenomyosis
It appears as focal low signal intensity bulge/region of the myometrium which may disappear on subsequent images or at cine MR imaging.
In obstetric imaging, the fetal transverse cerebellar diameter (TCD) is often measured as an additional fetal biometric parameter. It is measured as the maximal diameter between the cerebellar hemispheres on an axial scan. The value of the transverse cerebellar diameter in mm's is considered rou...
Transverse vaginal (transvaginal) septum (TVS) is a type of rare congenital uterovaginal anomaly (class II under the Rock and Adam classification).
It is rare with a frequency of 1 in 70,000 females.
In the case of a complete septum, patients commonly prese...
Triploidy is a rare lethal chromosomal (aneupliodic) abnormality caused by the presence of an entire extra chromosomal set.
It is considered the 3rd commonest fatal chromosomal anomaly 7. While it is thought to affect as much as 1-2% of conceptions, the vast majority are thought ...
Trisomies are chromosomal anomalies which usually occur due to non-disjunction. The vast majority of affected fetuses being spontaneously aborted, often very early during gestation. Only three are compatible with extra-uterine life (T13, T18, T21), and only one beyond early infancy (T21).
Trisomy 22 is an aneuploidic chromosomal anomaly which is usually fatal unless in mosaic forms.
Duplication of the short arm (p) and a small section of the long arm (q) of chromosome 22 can give result to the cat-eye syndrome - Schmidt-Fraccaro syndrome.
True hermaphroditism is a form of disorder of gender development.
Patients with true hermaphroditism have mosaicism of 46XX and 46XY. They therefore have both ovarian and testicular tissues.
There are three forms of true hermaphroditism:
unilateral true hermaphroditism
T-shaped uterus refers to a specific radiographic appearance of the endometrial cavity.
It is the most commonly associated abnormality from in utero diethylstilbestrol (DES) exposure, seen in 31% of exposed women. It is classified as a class VII Müllerian duct anomaly.
Tubal ectopic pregnancy (or adnexal ectopic pregnancy) is the most common location of an ectopic pregnancy.
It is the most common type of ectopic by far, accounting for 93-97% of cases.
Although the fallopian tube has many anatomical parts, for the purposes of ectopic ...
Tubal ring sign, also referred to as bagel sign or blob sign, one of the ultrasound signs of a tubal ectopic. It comprises of an echogenic ring which surrounds an unruptured ectopic pregnancy. It is said to have a 95% positive predictive value (PPV) for ectopic pregnancy.
Tuberculosis of the fallopian tube is one of the most common sites of tuberculous pelvic inflammatory disease.
Many patients may be asymptomatic, with the disease being discovered during the workup for infertility. Signs and symptoms are often vague and can include acut...
Tuberculous pelvic inflammatory disease refers to pelvic inflammatory disease due to Mycobacterium tuberculosis.
Genital tract involvement may be present in ~1.5% of cases of those affected with tuberculosis 4.
Infection almost always results from spread from an extrag...
Tubo-ovarian abscesses are one of the late complications of pelvic inflammatory disease.
Risk factors include 15:
previous pelvic inflammatory disease 16
multiple sexual partners
history of uterine surgery ...
Tunnel cluster (TC) is a type of Nabothian cyst characterized by complex multicystic dilatation of the endocervical glands.
Tunnel cluster is found in ~8% of adult women, 40% of whom are pregnant, almost exclusively multigravid women, and older than 30 years.
Turner syndrome, also known as 45XO or 45X, is the most common of the sex chromosome abnormalities in females.
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...
Ultrasound guided percutaneous drainage is one form of image guided procedure, allowing minimally invasive treatment of collections that are accessible by ultrasound study.
It has several advantages and disadvantages over CT, which include:
is a dynamic study, allowing greater prec...
Umbilical venous dilatation is a rare entity and often tends to occur as an isolated finding 4.
Dilatation of the umbilical vein can arise from a number of pathologies:
umbilical venous varix (UVV): particularly if focal
fetal hydrops: a focal dilatation due to an umbilical venous varix with...
Undifferentiated carcinoma of the endometrium is rare histological subtype of endometrial cancer. It is considered a high grade carcinoma, carries a poor prognosis and is often under-recognised 1.
It is thought to represent approximately 1-9% of endometrial cancers 1,6.
An undifferentiated carcinoma of the ovary is a rare type of ovarian epithelial tumor. They account for ~ 4% of ovarian cancer 2.
With these tumors, cellular differentiation is not sufficient for the tumor to be categorized into serous, mucinous or other specified subtypes. Pure undi...
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.
This type can account for ~10% (range 6-13%) of uterine anomalies and infertility is seen in ~12.5% (ra...
Urethral agenesis (or urethral atresia) refers to a situation where there is a congenital absence of the urethra. It can be a cause of fetal obstructive uropathy.
prune belly syndrome 5
bladder agenesis 2
May show a dilate...
Urethral diverticula, or urethroceles, are focal outpouchings of the urethra. They should not be confused with a ureterocele of the distal ureter.
Urethral diverticula occur far more frequently in women than in men and are estimated to occur in 1-6% of women, especially those with...
The urogenital triangle forms the anterior half of the diamond-shaped perineum. The triangle's corners are defined by the pubis symphysis anteriorly and the ischial tuberosities anterolaterally. The anterolateral borders are the ischiopubic rami and the posterior border is the transverse perinea...
Uterine agenesis is the extreme of Mullerian duct anomalies (Class I) where there is a complete absence of uterine tissue above the vagina.
The uterine agenesis-hypoplasia spectrum accounts for ~10-15% of all Müllerian duct anomalies.
Uterine arteriovenous malformations (UAVM) result from the formation of multiple arteriovenous fistulous communications within the uterus without an intervening capillary network.
The presentation can vary. UAVMs can cause life-threatening massive bleeding in young women....
The uterine artery is seen bilaterally and is a branch of the anterior division of the internal iliac artery.
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 ...
Uterine artery embolization (UAE) is an interventional radiological technique to occlude the arterial supply to the uterus and is performed for various reasons.
Uterine artery embolization has been practised for more than 20 years for controlling hemorrhage following delivery / abortio...
Uterine artery embolization (UAE) is used as an alternative to hysterectomy in selected patients and MRI assessment is key in allowing not only pre-procedure assessment but also assessing post-procedural outcome.
For a general discussion of the underlying condition refer to the article on ute...
Uterine artery flow notching refers to a phenomenon observed in uterine arterial Doppler ultrasound assessment.
The presence of notching after 22 weeks is associated with several other conditions including adverse pregnancy outcomes. These include
pregnancy induced hyp...
Uterine artery pseudoaneurysm (UAP) is a rare cause of secondary postpartum hemorrhage.
UAP usually presents as delayed (secondary) postpartum hemorrhage, that is per vaginal bleeding which occurs more than 24 hours and up to 6 weeks postpartum. However, some reported ca...
Uterine biophysical profile refers to assessment of uterus to produce a successful conception and implantation environment.
Uterine scoring system for reproduction (USS)
The uterine scoring system for reproduction comprises the following parameters, taken in mid-cycle:
1. endometrial thickne...
Uterine choriocarcinomas are one of the commonest choriocarcinomas and are often associated with gestational trophoblastic disease (GTD).
These tumors typically occur in women of childbearing age as a gestational choriocarcinoma. Most such cases present within one year of an ante...
Uterine dehiscence is, usually, used to refer to the process of gradual myometrial rupture without a rupture of membranes. However, the term is used synonymously with uterine rupture by some authors. It is often described in the context of C-section scar where it is also termed an incisional deh...
Uterine duplication anomalies are a group of Müllerian duct anomalies where fusion of the Müllerian duct associated structures fail to some degree:
uterus didelphys: class III
bicornuate uterus: class IV (second commonest duplication anomaly)
septate uterus: class V (commonest duplication ano...
Uterine enlargement can occur in a number of situations from both diffuse and focal processes. These include:
gestation related events
normal intrauterine pregnancy
molar pregnancy - gestational trophoblastic disease
postpartum uterus - still larger than usual
Uterine leiomyomas, also referred as uterine fibroids, are benign tumors of myometrial origin and are the most common solid benign uterine neoplasms. Commonly an incidental finding on imaging, they rarely cause a diagnostic dilemma. There are various medical, surgical and interventional treatmen...
Uterine leiomyosarcomas are malignant uterine tumors that arises from the myometrium. The uterus is the commonest location for a leiomyosarcoma.
Typically present in women in the 6th decade. They account for up to one-third of uterine sarcomas but only ~8% of all uterine cancers 1...
Uterine lipoleiomyomas result from degeneration of smooth muscle cells in an ordinary leiomyoma and represent a rare benign tumor of the uterus 1.
Lipoleiomyomas have a reported incidence of 0.03-0.20% and are typically found in postmenopausal patients with typical uterine leiomyo...
Uterine lymphoma refers to involvement of the uterus with lymphoma. Some authors also place lymphoma of the uterine cervix under this group.
It is rare condition with initial uterine involvement occurring in only 1% of patients with lymphoma 3. However, uterine involvement is more...
Uterine perforation represents a serious complication that can occur as a result of any type of intrauterine procedure or implantation. Some authors use the term uterine rupture synonymously with the term uterine perforation.
IUCD insertion: IUCD related uterine perforation
Uterine rupture is a rare but nevertheless potentially catastrophic complication that can occur in pregnancy.
The incidence rate in pregnancy is at 0.05% 6.
Uterine rupture is usually an acute presentation with haemodynamic instability and abdominal disc...
Uterine sarcoma is a malignant uterine tumor thats is composed of part or all sarcomatous (mesodermal) elements. They however account for a minority of all uterine malignancies (1-6% 3-4).
They can be broadly classified as pure or mixed 4:
malignant mixed Mul...
Uterine smooth muscle tumors of uncertain malignant potential (STUMP) is a recently defined entity by the World Health Organization for a heterogeneous group of uterine smooth muscle tumors that cannot be histologically diagnosed as unequivocally benign or malignant 1.
The uterine tube, also known as the Fallopian 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 tube. It can be affe...
The uterus is a hollow, thick-walled, muscular organ of the female reproductive tract that lies in the lesser pelvis.
The uterus has an inverted pear shape. In the adult, it measures about 7.5 cm in length, 5 cm wide at its upper part, and nearly 2.5 cm in thickness. It weighs ...
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.
Didelphic uteri account for approximately ~8% (range 5-11%) of Müllerian duct anomali...
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.
The estimated incidence is 1 in 10,000-40,000 births 3.
The acronym VACTERL derives from:
V: vertebral an...
The VACTERL-H association is a rare non-random association which bears the features of the standard VACTERL association with added fetal hydrocephalus.
Unlike the standard VACTERL association which is sporadic, the VACTERL-H is hereditary with both X-linked 3 and autosomal recessive 2 inheritan...
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.
The vagina is 8-10 cm in length, extending posterosuperior from the vestibule through the urogenital diaphragm to th...
Vaginal atresia refers to a spectrum of anomalies comprising of failure to form a part or all of the vagina.
It is considered the second most common cause of primary amenorrhea. The estimated
Incidence is at ~ 2 in 10000 women.
The most common symptom...
The staging of primary vaginal cancer covers for all histological sub types and is as follows
FIGO staging system
stage 0: carcinoma in situ
stage I: tumor confined to vagina
stage II: invasion of paravaginal tissues but no extension beyond pelvic side walls
stage III: extension to pelvic s...
The vaginal cuff is the remnant tissue after a hysterectomy. The cuff may be evaluated for tumor recurrence (often with ultrasound) if the uterus was removed for cervical or endometrial carcinoma.
The appearance of the cuff depends on what type of hysterectomy was perform...
Vaginal leiomyomas are an extremely rare entity and fall under extra-uterine pelvic leiomyomas.
They are extremely rare with only ~ 300 cases reported in literature 3.
It may occur anywhere along the vaginal canal and is usually localized, mobile, non-tender, and circ...
Vaginal lymphoma can refer to:
secondary involvement of the vagina (secondary vaginal lymphoma) from widespread generalised lymphoma
usually comprises of diffuse large cell B non-Hodgkin's lymphoma (DLBCL) 2
primary vaginal lymphoma
A vaginal pessary is a device inserted into the vagina which can either be mechanical or pharmaceutical.
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 alt...
Vaginal stenosis refers to a narrowing of the vagina, it can be congenital or acquired.
Acquired causes include
scarring from prior pelvic irradiation - brachytherapy
Depending on the site of stenosis and state of menstruation there can be a...
The Valsalva maneuver is the forced expiration of air against a closed airway, resulting in increased intra-abdominal, intrathoracic and pharyngeal pressure. It can be performed against a closed glottis or by one closing the mouth and pinching the nose while forcibly exhaling.
It is commonly us...
Vascular Ehlers-Danlos syndrome (EDS) or type IV Ehlers-Danlos syndrome (EDS 4) is the most malignant form of Ehlers-Danlos syndrome. This form is often accompanied by neurovascular complications secondary to vessel dissections and/or aneurysms.
Vascular EDS represents about 4% of...
The Venetian blind artifact (shadows) is a sonographic finding that is typically associated with adenomyosis but can also occur in uterine fibroids. The Venetian-blind artifact associated with adenomyosis is typically "thin" whereas when associated with uterine fibroids, there are also edge shad...
Vesicovaginal fistulas are abnormal fistulous connections between the urinary bladder and vagina, resulting in an involuntary discharge of urine through the vagina.
The overall incidence of vesicovaginal fistula is unknown but was reported to be 2.11 per 100 births in Nigeria 1.
Vesicovaginal reflux is a well-known entity rarely encountered by radiologists. It is a behavioral disorder, a type of dysfunctional elimination syndrome commonly encountered in pre-pubertal girls. It is defined as reflux of urine into the vaginal vault either in supine or upright position durin...
A vestibule is an anatomical term and refers to a small cavity at the proximal end of a tube.
History and etymology
Vestibule derives ultimately from the Latin...
The vestibule of the vulva (vestibule of the vagina in some texts 2) is the area between the labia minora, and posterior to the glans of the clitoris. It marks the boundary between the vagina and the vulva. The urethra, vagina and the greater vestibular glands open out into the vestibule.
The vulva (or pudendum) is the collective term given to the female external genitalia.
The vulva consists of the:
vestibule of the vulva
Individual component st...
Staging of vulval cancer is the FIGO staging system and is as follows:
stage 0: carcinoma in situ (pre-invasive); corresponds to Tis
stage I: tumor <2cm (greatest dimension) and confined to vulva/perineum; corresponds to T1
stage Ia: stromal invasion by <1mm
Stage Ib: stromal invasion by >1m...
Vulval neoplasms are rare and mostly seen in an elderly female patients. Squamous cell carcinoma is most common malignancy of the vulva which only 30% of them are associated with oncogenic HPV viruses.
Squamous neoplastic lesions
classic vulvar intraepithelial neopla...
The whirlpool sign of the mesentery, also known as the whirl sign, is seen when the bowel rotates around its mesentery leading to whirls of the mesenteric vessels.
The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation).
The whirlpool sign or whirl sign of ovarian torsion is characterized by the appearances of a twisted ovarian pedicle seen on US or even on CT.
The term whirlpool sign is used in other contexts: see whirlpool sign (disambiguation).
The WHO histological classification is a detailed classification of tumors of the uterine cervix.
squamous tumors and precursors
squamous cell carcinoma, not otherwise specified - 8070/3
keratinizing - 8071/3
non-keratinizing - 8072/3
basaloid - 8083/3
verrucous - 8051/3...