Shortening of the uterine cervical canal as the name implies refers to an abnormal shortening of the uterine cervical length. It is considered a sign of cervical incompetence during pregnancy and can lead to premature delivery.
primary (i.e. congenital/idiopathic)
A short maxillary length can result from many congenital and acquired causes. If seen in an antenatal ultrasound scan, it is often considered to have a high association with trisomy 21 1.
Many conditions that can cause midfacial hypoplasia will result in a short maxillar...
Short rib polydactyly syndrome(s) (SRPS) comprise a rare group of severe osteochondrodysplasias. There are four major recognized types present:
type I: Saldino-Noonan type
type II:: Majewski type
type III: Verma-Naumoff type
type IV: Beemer-Langer type
There may also be other very rare type...
SHORT syndrome refers to an acronym which primarily comprises of the following features:
S: short stature
H: hyperextensibility of joints and/or inguinal hernia
O: ocular depression
R: Rieger anomaly
T: teething delay
In addition to these there can be numerous associated minor features whi...
A short umbilical cord has been variably defined. Considering the mean length of the umbilical cord is 50-70 cm 1,2, a short cord in absolute terms is usually taken as one that is under 35-40 cm in length at term 1,2.
Recognized associations include
Sirenomelia (also known as the mermaid syndrome) is a rare congenital malformation characterized by the fusion of lower limb structures.
The estimated incidence is at ~1 in 60,000-70,000 of pregnancies 9. There may be greater male predilection (somewhat paradoxical given the usage...
A Sister Mary Joseph nodule is a metastatic lesion involving the umbilicus. The most common primary source is an intra-abdominal adenocarcinoma.
Umbilical metastases are uncommon, reportedly present in 1-3% of all intra-abdominal and/or pelvic malignancy 7.
The loss of the normal sliding sign is a dynamic sonographic sign performed during transvaginal ultrasound (TVS) of women with suspected pelvic peritoneal endometriosis. It indicates pouch of Douglas (POD) involvement and obliteration and is suggestive of deep infiltrating endometriosis (DIE).
Small cell carcinoma of the cervix is a rare histological subtype of carcinoma of the cervix.
Small cell carcinoma is thought to account for ~0.5-6% of all uterine cervical cancers 3.
It is a type of neuroendocrine tumor and is similar to pulmonary small cell carcino...
Snowstorm sign may refer to:
snowstorm sign: complete hydatiform mole (ultrasound)
snowstorm sign: extracapsular breast implant rupture (ultrasound)
snowstorm sign: thyroid pulmonary metastases (chest radiograph)
Soft-tissue sarcomas are a heterogeneous group of malignant tumors of mesenchymal origin (sarcoma) that originate from the soft tissues rather than bone. They are classified on the basis of tissue seen on histology. The commoner sarcomas in the adult and pediatric population are listed below.
Obstetric and gynecological ultrasound is rampant with numerous cut off values. Some of these get revised over the years. The following list is a useful aid to refer to and revise.
rate of increase of a mean sac diameter per day in early pregnancy
generally accepted value for a thi...
Sonohysterography, also referred as saline-induced sonohysterography (SIS), is an ultrasound technique that better characterizes the uterine cavity and endometrium. It is particularly useful for evaluation of endometrial polyps.
fertility evaluation / recurrent pregnancy loss
Specialized teratomas of the ovaries are a rare subtype of ovarian teratomas where there is a monodermal differentiation of tissue element. Therefore they usually contain only endodermal, ectodermal or mesodermal elements.
Entities that are classified under this sub group include:
The squamo-columnar junction (SCJ) of the cervix refers to a transitional area between squamous epithelium of the vagina and the columnar epithelium of the endocervix. This shifts in location through age from being more external to internal. Carcinoma of the cervix develops almost exclusively wi...
Squamous cell carcinoma (SCC) of the cervix is the most common histological subtype of cervical cancer and accounts for 80-90% of cases.
Most cervical squamous cell carcinomas grow at the squamocolumnar junction (SCJ). In younger women, the SCJ is located outside the external uterine...
Squamous cell carcinoma (SCC) of the ovary is extremely rare and usually arises in a mature cystic ovarian teratoma 2. As only parts of the lesion are composed of malignant tissue, it is difficult to diagnose malignant transformation of a teratoma preoperatively, unless invasion into adjacent st...
Stenosis of the uterine cervix is the pathologic narrowing of the uterine cervix. The term cervical stenosis is clinically defined as cervical narrowing that prevents the insertion of a 2.5 mm wide dilator through the cervical os.
One-fifth of patients have a history of exposure t...
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 ultrasound in polycystic ovarian syndrome
string of pearls sign for angiographic appearances in fibromuscular dysplasia
string of pearls sig...
The string of pearls (or beads) sign in the ovary is the ultrasound sign of multiple small (<5 mm) follicles peripherally located in the gonad.
It is typically seen in polycystic ovaries, and is thought to represent abnormal accumulation of immature follicles. This morphologic appearance howeve...
Struma ovarii tumor is a subtype of an ovarian teratoma and is composed entirely or predominantly of thyroid tissue and containing variable-sized follicles with colloid material.
It accounts for 0.3-1% of all ovarian tumors and ~3% of all mature cystic teratomas 1.
Subendometrial cysts can arise from several pathologies which include
tamoxifen-associated endometrial changes 1,3
superiorly positioned nabothian cyst
The subendometrial halo is a hypoechoic stripe formed at the innermost part of the myometrium directly bordering the endometrium. It is important to assess its continuity in order to rule out myometrial invasion in endometrial carcinoma.
This hypoechoic line may be thickened in case of adenomyo...
Getting a film with submucosal fibroid in the exam is one of the many exam set-pieces that can be prepared for.
Transabdominal and transvaginal pelvic ultrasound scans show an anteverted uterus with endometrium that is 7 mm wide and has a trilaminar appearance indicative of the pe...
Submucosal leiomyomas of the uterus refer to a subtype of uterine leiomyoma that primarily projects into the endometrial cavity. They are least common albeit the most symptomatic type of leiomyoma.
Submucosal leiomyomas can be a common source of abnormal uterine bleeding ...
Subserosal uterine leiomyoma is a subtype of uterine leiomyoma that often exophytically projects outwards from a subserosal location. While its exact definition may vary, a leiomyoma is often called subserosal if >50% of the fibroid protrudes out of the serosal surface of the uterus 2.
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 intentionally left in the operative bed, not to be confused with a gossypiboma which is caused by foreign material left behind in error. Its use has increased with the advent of minimally invasive s...
There are various classic surgical positions for patients to be placed in for procedures, which have been adopted/repurposed for interventional radiology and some diagnostic procedures:
reverse Trendelenburg position
lateral decubitus position
Syndactyly (plural: syndactylies) 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...
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, ...
The oncological agent tamoxifen has pro-oestrogenic changes on the endometrium resulting in abnormal growth 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...
Torsion of subserosal leiomyoma of the uterus refers to the twisting of the attached pedicle of a pedunculated subserous leiomyoma of the uterus with subsequent ischemia, necrosis and gangrene 1.
acute abdominal pain
GIT symptoms (e.g diarrhea)
tenderness in the lower ...
Trachelectomy, also known as a cervicectomy, refers to surgical resection of the uterine cervix. It may be considered as a fertility-sparing treatment for low-stage cervical cancer.
Although radical hysterectomy is routine for treatment of endometrial and more advanced cervical cancer, uterine-...
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 ...
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 an echogenic ring that 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 for tubo-ovarian abscesses include 15:
previous pelvic inflammatory disease 16
multiple sexual partners
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-recognized 1.
It is thought to represent approximately 1-9% of endometrial cancers 1,6.
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 undiffe...
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...
Ureterovaginal fistulae refer to abnormal communications between the lumina of the ureter(s) and the vagina.
Patients usually present with urinary incontinence through the vagina which may be accompanied by fever and chills 1. Symptoms usually begin within 2-4 weeks foll...
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 caruncles are the most common urethral lesion in postmenopausal women.
The lesion accounts for >90% of urethral masses in postmenopausal women 2.
Most women are asymptomatic, but caruncles can cause pain, dysuria or bleeding 4. On physical examinat...
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/abortion,...
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 inversion is a rare condition in which the uterus is essentially turned inside out. There are two types: "puerperal" (within six weeks of childbirth) and "non-puerperal". The reason for uterine inversion is unclear. In the puerperal form, it is theorized that excessive traction on the um...
Uterine leiomyomas also referred to 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 treat...
Uterine leiomyosarcomas are malignant uterine tumors that arise from the myometrium. The uterus is the commonest location for a leiomyosarcoma.
Typically, these tumors present in women in the 6th decade. They account for up to one-third of uterine sarcomas but only ~8% of all uter...
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 0.05% 6.
Uterine rupture is usually an acute presentation with hemodynamic instability and abdominal discomfo...
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 venous plexus is a network of veins surrounding the uterus and has extensive anastomoses with the vaginal venous plexus inferiorly and ovarian venous plexuses laterally.
The uterine venous plexus lies along the lateral aspects and superior angles of the uterus within ...
The paired uterosacral ligaments are one of the supporting structures of the uterus. Uterosacral ligaments are not infrequently affected in cases of deep infiltrating endometriosis.
The paired uterosacral ligaments are extraperitoneal structures which extend posteriorly from the ...
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 all histological subtypes 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 side w...