Development and congenital anomalies of urogenital system
Development and congenital anomalies
of urogenital system
Moderator : Dr. (Mrs) Nabanita Deka
Presenter : Dr. Jayeta Choudhury
Department of Radiology
Gauhati Medical College
Functionally, the urogenital system can be divided
into two entirely different components: the urinary
system and the genital system.
Embryologically and anatomically, however, they are
Both develop from a common mesodermal ridge
(intermediate mesoderm) and open into a common
channel the cloaca.
“Ontogeny Recapitulates Phylogeny”
Ernst Haeckel 1860
Ontogeny is the development of
Phylogeny is the evolution of
So this is the idea that during
development an organism (or an
organ) goes through the same
stages as during their evolution.
The kidneys are a perfect example.
URINARY SYSTEM : Kidney Systems
• Three slightly overlapping kidney systems are formed in a cranial-tocaudal sequence during intrauterine life in humans: the pronephros,
mesonephros, and metanephros.
• Beginning of the 4th wk (21days).
•The pronephros is represented by 7 to
10 solid cell groups in the cervical
•Their excretory units: are called
•By the end of the fourth week, all
indications of the pronephric system
•Appear late in the 4th wk
• From the thoracic and lumbar
seg of intermediate mesoderm.
•They function as interim
kidneys for approximately 4 wks.
• Excretory tubules form their
basic unit which open into
•The mesonephric ducts open
into the cloaca.
METANEPHROS: THE DEFINITIVE KIDNEY
•Appears in the 5th wk.
•Develops from sacral segments of the intermediate mesoderm .
•However, the development of the duct system differs from that of the other
Collecting ducts of the permanent kidney develop from the URETERIC BUD, an
outgrowth of the mesonephric duct close to its entrance to the cloaca .
The bud penetrates the metanephric tissue, which is moulded over its distal
end as a cap .
Subsequently, the bud dilates, forming the primitive renal pelvis, and splits and
subsequently divides and sub divides to finally give rise to approximately 1 to 3
million collecting tubules.
Hence, the kidney develops from two sources: (a) metanephric
excretory units and (b) the ureteric
bud, which gives rise to the collecting system. At birth, the
mesoderm, which provides
kidneys have a lobulated appearance, but the lobulation disappears
during infancy .
POSITIONAL CHANGES OF THE KIDNEYS
• Initially : close/ pelvic / anterior to the sacrum .
• Gradually come to lie in the abdomen and move farther apart .
• Attain their adult position by 9th wk. This relative ascent results
mainly from the growth of the embryo's body caudal to the kidneys .
• Initially the hilum : faces ventrally; however, as the kidney relocates
(ascends), it rotates medially almost 90 degrees.
• By the 9th week, the hilum is directed anteromedially .
Development of Bladder and Urethra
During the 4th to 7th weeks of development,
MOST OF THE
* THE BLADDER NECK
* THE PROSTATIC PART OF
URETHRA IN MALES
* THE ENTIRE URETHRA IN
REST OF THE
Initially, the bladder is continuous with the
allantois, but when the lumen of the allantois
is obliterated, a thick fibrous cord, the
urachus, remains and connects the apex of
the bladder with the umbilicus . In the adult,
it forms the median umbilical ligament.
INTO THE WALL
•Sex differentiation is a complex process that involves
•The key to sexual dimorphism is the Y chromosome,
which contains the testis-determining gene called
the SRY (sex-determining region on Y) gene in its
short arm (Yp11).
• Weeks 1-6 sexually indifferent or undifferentiated
• Week 7 begins phenotypic sexual differentiation.
• The sex of the fetus may be discerned by
ultrasound as early as 12 weeks gestation. However,
it can be determined with 95-100% accuracy only
at or after 20wks.
At day 8, cells of the inner cell mass of the blastocyst differentiate into :
hypoblast and epiblast layers.
Primordial germ cells originate in the epiblast, migrate through the
primitive streak, and by the 3rd week reside among endoderm cells in the
wall of the yolk sac close to the allantois.
During the 4th week, they migrate by ameboid movement along the dorsal
mesentery of the hindgut , to reach the primitive gonads in the genital
The gonadal ridges appear as a pair of longitudinal ridges, on either side of
The primordial germ cells have an inductive influence on the
development of the gonad into ovary or testis.
Shortly before and during arrival of primordial
germ cells, the epithelium of the gonadal ridge
proliferates, and epithelial cells penetrate the
underlying mesenchyme. Here they form a
number of irregularly shaped cords, the
primitive sex cords .
These sex cords and the germ cells make up
the ovary and testis.
Genital Ducts in the Male
TOWARDS THE HILUM
THE TESTIS CORDS
BREAK UP INTO A
NETWORK OF TUBULES
FORMING THE RETE
JOINS THE EFFERENT
DUCTULES WHICH ARE
DERIVATIVES OF THE
Genital Ducts in the Female
• The paramesonephric duct arises as a longitudinal
invagination of the epithelium on the anterolateral
surface of the urogenital ridge .
• Cranially, the duct opens into the abdominal cavity
with a funnel-like structure. Caudally, it first runs
lateral to the mesonephric duct, then crosses it
anteriorly to fuse with the duct from the other side in
• The two ducts are initially separated by a septum
but later fuse to form the uterine canal.
Fate of the mesonephric duct, mesonephric
ductules and parameso nephric duct
ejaculatory duct in
for some remnants
e.g. duct of
epoophoron, duct of
* Efferrent ductules
Females : tubules
- Caudal end
uterus and 4/5ths
Formation of the vagina
Thus, the vagina has a dual
with the upper portion (four
fifth) derived from the uterine
the lower portion derived from
the urogenital sinus.
EXTERNAL GENITALIA : INDIFFERENT STAGE
In the 3rd wk, mesenchyme cells originating in the region of the
primitive streak migrate around the cloacal membrane to form a
pair of slightly elevated cloacal folds.
ANOMALIES OF FORM
Unilateral renal agenesis :
• 1 in 1000
• Males / left kidney
• Unilateral renal agenesis should be suspected in infants with a single
• The term LYING DOWN ADRENAL SIGN as been ascribed to the
elongated appearance of the adrenal not normally molded by the
Bilateral renal agenesis :
• 1 in 5000
• Results when the ureteric bud fails to develop or it fails to penetrate
the metanephrogenic blastema
• Is incompatible with postnatal life because of the associated
• There is associated with oligohydramnios.
• These infants have a characteristic facies, club feet and other
anomalies called “ POTTER’S SEQUENCE”
RENAL HYPOPLASIA :
• Unusual renal anomaly in which the kidney is at least 50% smaller than
normal and typically contains fewer than the normal number of calyces.
• Usually unilateral, and the kidney functions normally for its size.
• There are varoius acquired causes of unilaterally small kidneys .
• Can be differentiated from hypoplasia :
* by the normal number of calyces
* and normal cupping of the calyces
• The ASH-UPMARK KIDNEY was prevoiusly thought by some to be a
variant of renal hypoplasia. However, it is currently thought to be caused by
scarring due to chronic pyelonephritis with cortical loss at its upper pole.
• A supernumerary kidney is extremely rare.
• Cleavage of the metanephric blastema has
been suggested as the cause for this
•Most supernumerary kidneys are caudally
placed and are hypoplastic.
• They may be connected to the ipsilateral
dominant kidney either completely or by loose
areolar connective tissue.
ANOMALIES OF POSITION
• Malrotated kidneys
• Ectopic kidneys
If a kidney fails to rotate, the hilum faces
anteriorly, that is, the fetal kidney retains its
embryonic position . If the hilum faces
posteriorly, rotation of the kidney proceeded
too far; if it faces laterally, lateral instead of
medial rotation occurred. Abnormal rotation
of the kidneys is often associated with
• Renal ectopia results from failure of normal ascent of the embryonic
• Ectopic kidneys lie outside the renal fossa and may be:
^pelvic ^lie opposite the sacrum ^ below the aortic bifurcation ^iliac ^
thoracic ^ crossed .
• They are often small, lobulated kidneys with abnormal rotation with
extrarenal pelvis and an irregular vascular supply.
•The most common problem associated with an ectopic kidney is vesicoureteric reflux (VUR) (85%), pelvi-ureteric junction (PUJ) obstruction (3352% ) and renal calculi .
ANOMALIES OF FUSION
• These anomalies are thought to result because of an
abnormally situated umbilical artery that prevents normal
cephalic migration from occurring.
• In all fused kidneys, the arterial supply and venous
drainage are grossly abnormal.
• 1 in 400
• Horseshoe kidney is the most common renal fusion
• It consists of two distinct functioning kidneys lying
vertically on either side of the midline, connected at
their lower poles by an isthmus of functioning renal
parenchyma or, rarely, fibrous tissue that crosses the
midline of the body .
• In rare instances, the upper poles may be the site of
• The position of the isthmus and hence the kidneys are variable :
40% : the isthmus lies at level of L4 just below the origin of the IMA
Another 40% : the isthmus is located in a normal anatomical
position of the kidneys
Remaining 20% :kidneys lie lower in the pelvis
• Ureters may have the so-called “FLOWER-VASE
APPEARANCE” , in which the upper ureters
diverge laterally over the isthmus and then
• Because of their abnormal course, the ureters are
prone to be obstructed, precipitating
hydronephrosis, infection and stone formation.
• Some authours have reported HSK to be
associated with increased risk for renal neoplasms
such as Wilms tumors, renal carcinoids, and
transitional cell carcinoma.
CROSSED FUSED RENAL ECTOPIA
• Incidence : 1 in 1000
• 2 : 1 male
•The left kidney is most frequently ectopic, 3 : 1
• Origin : abnormal migration of ureteral bud.
• One kidney crosses over to opposite side, and the parenchyma
of the two kidneys fuse.
• Most commonly, the upper pole of the inferiorly positioned
crossed ectopic kidney is fused to the lower pole of the
superior, normally positioned kidney. The ureter of the ectopic
kidney crosses the midline and enters the bladder on the
opposite side .
McDonald and McClellan classified crossed ectopic kidney into
four types: crossed renal ectopia with fusion (85%), crossed renal
ectopia without fusion (10%), solitary crossed renal ectopia and
bilaterally crossed renal ectopia .
Six variations of crossed fusion have been described. In decreasing
order of frequency, they are
type 1: inferior crossed fused ectopia
type 2: sigmoid or S-shaped kidney
type 3 :unilateral lump kidney
type 4: unilateral disc kidney
type 5: L-shaped kidney
type 6: superior crossed fused ectopia
CAKE KIDNEY (COMPLETE RENAL FUSION)
• Pan Cake kidney is a rare congenital anomaly of the genitourinary
system,with fewer than 30 cases described in the literature .
•The term cake kidney or fused pelvic kidney was defined by Glenn as an
anomaly in which “the entire renal substance is fused into one mass,
lying in the pelvis, and giving rise to two separate ureters which enter the
bladder in normal relationship”
•In rare instances, such kidneys possess one ureter .
•The fused kidney occupies prevertebral or presacral space .
•The cake kidney may remain asymptomatic and be detected at autopsy.
•It may become infected or may cause local pain from dragging on the
renal vessels by the weight of the organ
CONGENITAL CYSTIC RENAL DISEASES
• Renal cysts detected in utero and after birth
has been a topic of considerable confusion.
• A standardized step-by-step sonographic
approach is most helpful in differentiating
renal cystic diseases.
• This approach must be combined with the
clinical data, familial history, and in some
cases, complementary examinations.
Once renal cystic disease is suspected, the first step is to rule out
Dysplasia associated with obstructive uropathy the features of
• Dilated PCS
• Hyperechoic kidneys
• Multiple cysts
• Can be normal, enlarged or small/ Unilateral or Bilateral
Next step is to consider Multicystic Dysplastic kidneys:
• Multiple cysts throughout the kidney without communication.
• No renal parenchyma in between
• Atretic ureter
• Vascular pedicle may also be absent or atretic
Both obstructive dysplasia and MCDK
should be differentiated from complex
cysts, which include cystic tumors like
If the foregoing diagnoses are unlikely, inherited renal cystic
disease should be considered.
If no familial history is present, cases are further split
patients with renal findings limited to the kidney
renal anomalies are associated with other organ malformations
Both these groups can be separated into
those with typical ultrasound patterns suggestive of specific
those with atypical ultrasound patterns.
The ARPKD pattern:
• Bilateral, very large (> 4 SD) kidneys
• Diffusely hyperechoic kidneys
• Loss of CMD with or without evident cysts
• Oligohydramnios is the rule
• Very large hyperechoic kidneys with hyperechoic medulla
(reversed CMD) is another typical pattern.
•The next step is to rule out Glomerular cysts (GCKD) (AD):
• It also includes hyperechoic and enlarged (+2 SD) kidneys without
CMD but there are charecteristic multiple subcapsular as well as
Third typical pattern is Nephronophthisis:
• autosomal recessive tubulointerstitial
• urinary concentration defects and anemia
At ultrasound :
the kidneys are hyperechoic, normal-sized or
small, and without CMD.
renal cysts typically develop at the
Multiple congenital syndromes are also
associated with renal cysts. These should also
be kept in mind while dealing with a case of
renal cysts in utero or in a child . This
•Bardet-Biedl syndrome (BBS)
ANOMALIES OF RENAL PELVIS
- Polycalicosis and Congenital Megacalyces
- Calyceal diverticula
- Aberrant (Ectopic) Papilla
- Ureteropelvic Junction Obstruction
- Congenital Megaureter
- Duplex Collecting Systems
CONGENITAL MEGACALYCES/ PUIGVERT'S DISEASE
Calyces are asymmetrically dilated. Renal pelvis is
normal. Some doubt its congenital nature.
• 4.5 : 1000
• Focal extrinsic dilatation of a
• In 1/3 patients : stones can form
URETEROPELVIC JUNCTION OBSTRUCTION
• Congenital obstruction of the UPJ is a common anomaly of the
• The disorder produces caliectasis and marked pelviectasis as a result
of a functional narrowing of the UPJ.
• In 5% cases : extrinsic compression by an aberrant renal artery
• Males (2:1), Left sided
• Commonly presents as an abdominal mass in a neonate.
• In some cases, symptoms may present in the setting of a sustained
diuresis, a condition that has become known as "beer-drinker's
On urography, a dilated renal pelvis and calyces will be demonstrated.
Because of the dilation, slow opacification of the affected side is the
rule and delayed radiographs are usually necessary.
DIFFERENTIATING UPJ FROM EXTRA RENAL PELVIS IS IMPORTANT.
• USG and CT reveal similar findings.
• In patients with equivocal UPJ
obstruction, or in cases where there is a
discrepancy between the patient's
clinical symptoms and the radiologic
findings, diuresis renography or the
Whitaker procedure may be employed.
DUPLICATION OF THE URETER :
• Results from early splitting of the ureteric bud .
• Duplication can be variable. At one end of the spectrum there is
merely duplication of the renal pelvis, draining via a single ureter.
At the other extreme, two separate collecting systems drain
independently into the bladder or ectopically (see below)
• Duplex systems may be unilateral (more common) or bilateral.
•Partial or complete.
Duplication of a renal pelvis (1 in 40) :
Duplication of a renal pelvis is the most common
congenital abnormality of the upper renal tract .
• drains inferomedially
• can drain ectopically
• usually associated with an
• drains superolaterally
• is usually associated with VUR
• CT is able to delineate essentially all abnormalities, especially
when performed during the excretory phase. A duplicated renal
collecting system can be suspected by identifying the so
called faceless kidney .
PRIMARY MEGAURETER :
• Megaureter is a generic term indicating the presence of an enlarged
ureter with or without concomitant megacalyces.
• The normal ureter in children rarely exceeds 5 mm in diameter . In
practice, a ureter with a diameter of 7 mm or more should be considered
a megaureter .
• There are three major categories of primary megaureter:
obstructed primary megaureter
refluxing primary megaureter
nonrefluxing unobstructed primary megaureter
•Secondary megaureter occurs as a result of some abnormality
involving the bladder or urethra (eg, urethral valves, strictures,
Obstructed primary megaureter: a condition akin to achalasia and
Hirschsprung disease. The normal ureter proximal to the aperistaltic
segment dilates because of relative obstruction.
There is associated hydronephrosis, and active peristaltic waves can be
seen on ultrasound.
Refluxing primary megaureter :is caused by a short or absent
intravesical ureter, congenital paraureteric diverticulum, or other :
derangement of the VUJ.
Vesicoureteric reflux can be demonstrated in this.
Nonrefluxing unobstructed primary megaureter: there is neither
reflux nor stenosis of the vesicoureteral junction, but the ureter is
dilated beginning at a point just above the bladder .
Most primary megaureter in neonates fall into this category.
ANOMALOUS TERMINATION OF
- ECTOPIC URETER
- URETEROCELE : ORTHOTOPIC OR ECTOPIC
•Ectopic insertion of the ureter occurs due to abnormal ureteral bud
migration and usually results in caudal ectopia.
•70% are associated with complete ureteral duplication.
• In the female, it can insert urethra, vestibule, or vagina. More rarely,
it can empty into the uterus or Gartner duct or cyst.
• In males, it empties into the lower bladder, posterior urethra, seminal
vesicle, vas deferens, or ejaculatory duct. In very rare instances, it can
empty into the rectum.
VESICO URETERAL REFLUX
• VUR is the abnormal flow of urine from the bladder into the upper
• Cause :
primary maturation abnormality of the VUJ
short distal ureteric submucosal tunnel
due to an associated congenital anomaly
• Reflux predisposes to renal infection (pyelonephritis).
• The majority of pediatric patients who develop renal scars after a
urinary tract infection have VUR.
• Detection of VUR in neonates and infants is particularly important
because these patients are more predisposed to the development of
renal scars and renal failure than are older children.
• Reflux is also the most common cause of antenatal
•The primary diagnostic procedure for evaluation of VUR is
VCUG, which should be performed after the first episode of
urinary tract infection.
• VCUG should be used to document the presence of VUR
and to determine the grade of reflux and whether reflux
occurs during micturation or during bladder filling.
Grades of VUR Based on Guidelines of the International Reflux Study
Echo-enhanced cystosonography has recently been
proposed as a promising new method for detecting
and grading VUR without exposing patients to
• Ureteroceles represent cystic dilatation of the intravesical
segment of the ureter.
• The defect is in the obstruction of the meatus, and the
ureterocele is simply a hyperplastic response to this
obstruction with the bladdder and ureteral mucosa prolapsing
• They may be
25% - a ureterocoele that occurs at a VUJ in a
75% - that which occurs at a VUJ whose site is
abnormal (duplex ureter)
At US: the ureterocele is identified as a
cystic intravesical mass, contiguous with a
In IVP: demonstrates a collection of
contrast material within the ureterocele :
which produces the classic “cobra head”
appearance consisting of a round or oval
area of increased opacity surrounded by the
radiolucent halo of the wall of the
In VCUG: a ureterocele usually
manifests as a rounded filling defect within
PRUNE BELLY SYNDROME
• is also called Eagle-Barrett syndrome
• exclusively in males
• Renal anomalies include
Ureters: dilated :
segmental or total /
Bladder: large/ Patent
Dilated posterior urethra :
PUV like picture
ABNORMALITIES OF THE BLADDER
- Bladder Duplication
- Bladder diveriticulum
- Bladder ears
VESICAL EXSTROPHY COMPLEX
Depending on the timing of the intrauterine insult, defect in lower anterior
abdominal wall defect and premature perforation of the cloacal membrane
results in a spectrum of diseases.
30% are epispadias, 60% are classic bladder exstrophy, and less than 10% are
Incidence of bladder exostrophy : 0.25-0.5 per 10,000 births
Males ( 2:1)
Ante natal USG findings :
Lower abdominal wall defect with protruding
Absence of the normally filled urinary bladder.
No sign of oligohydramnios or other gross renal
Colour Doppler shows umbilical arteries alongside
the abdominal wall mass
External genitalia malformation, pubic diastasis etc
• Can be complete or incomplete.
• In incomplete bladder duplication, two bladders
communicate with each other and drain into a
• Complete duplication is very rare : 40 cases in
• Duplication of the bladder may occur in the sagittal
or coronal plane. The most common form is sagittal
duplication with the bladders lying side by side.
• Each bladder receives the ureter of the ipsilateral
kidney and is drained by its own urethra.
• Congenital BD : occur without obstruction
• Male predominance
• Described as herniation of mucosa through bladder
• Usually > 2cm, solitary
• Types : 90% paraureteral : associated with VUR :
“ Hutch Divericula”
10 % postero-lateral : not associated with VUR
CONGENITAL URACHAL REMNANT ABNORMALITIES
• Refers to a series of potential anomalies that can occur in
association with the urachus.
• There are four types of congenital urachal remnant anomalies.
Patent urachus : commonest ~ 50 %
Urachal Cyst : next commonest : ~ 30 %
Urachal-umbilical sinus : ~ 15 %
Vesicourachal diverticulum : ~ 5 %
Usually midline : may occasionally
deviate laterally to merge with one of
the obliterated umbilical arteries
POSTERIOR URETHRAL VALVES
• M.C congenital obstructive lesion of urethra, occurring only in
• Speculated to be a result of abnormal insertion of the
mesonephros into cloaca.
• It courses obliquely from the verumontanum to the most distal
portion of the prostatic urethra in a bicuspid or unicuspid
• VUR with gross hydronephrosis, dysplastic kidneys, and urine
ascites are common findings in such a patient.
The urethral meatus is
located on the ventral
surface, anywhere from the
penile shaft to the
ANTERIOR URETHRAL VALVES
•These are rare congenital anomalies that cause lower
urinary tract obstruction in children.
•Anterior urethral valves may be found anywhere in the
•Most commonly in bulbar urethra.
CONGENITAL URETHRAL DUPLICATION
It is a rare anomaly. Commonly ,the duplication commonly occurs in the
sagittal plane. Effmann Class.
I : Blind ending
I I A: double meatus
I I: Patent assesory urethra
I I B: single meatus
III : Assesory urethra from duplicated bladder
MULLERIAN DUCT CYSTS AND PROSTATIC UTRICLE
MULLERIAN DUCT CYSTS
• Nonatrophy of the mullerian duct may produce cystic dilations along the
route of the vas deferens from the scrotum to the ejaculatory ducts .
• Mullerian duct cysts are rare, but most commonly occur in the midline just
above the prostate.
• The prostatic utricle is a small, blind-ending midline pouch arising from the
prostatic urethra at the level of the verumontanum.
• The normal prostatic utricle is 8 to 10 mm in length, narrow at its orifice (2
• It may be associated with urinary retention, stasis, and infection.
This is a rare congenital anomaly resulting from the faulty development of
the corpora cavernosa and corpus spongiosum.
Two types are described.
Milder form : scaphoid variety. More severe form : fusiform variety
MULLERIAN DUCT ANOMALIES
Phase of Organogenesis : one or both ducts
may not develop completely leading to
complete agenesis / hypoplasia / unicornuate
Phase of lateral fusion : where the lower segments of the
Mullerian ducts fuse to form uterus, cervix and upper 4/5 ths
vagina. Failure of this could lead to Bicornuate or Didelphys
Vertical fusion is referred to ascending sinovaginal bulb
fusion to descending Mullerian system. Incomplete fusion
would produce transverse vaginal septum.
Septal resorption : After lower Mullerian
system fuses, septum which is present gets
resorbed naturally. Failure leads to septate
• Developed by the American Fertility Society (AFS)
• Developmental anomalies of the renal system is common. Renal
agenesis is the most commonly reported anomaly, ( 67% ).
• Many of the anomalies are initially diagnosed at HSG and USG ;
however MR imaging is the study of choice because of its high
accuracy and detailed elaboration of uterovaginal anatomy.
• Three-dimensional ultrasound with multiplanar imaging has
been shown to be more accurate than plain TVS.
• Laparoscopy and hysteroscopy are reserved for women in whom
interventional therapy is likely to be undertaken.
CLASS I — AGENESIS/HYPOPLASIA (5-10% )
• Early developmental failure of the Mullerian ducts, results in
various degrees of agenesis or hypoplasia of the uterus, cervix
and upper 4/5 ths of the vagina.
• In agenesis a uterus is not identified or small amounts of
rudimentary tissue without differentiation may be identified.
• The most common form is the Mayer–Rokitansky– Kuster–
90% cases : vaginal + uterine agenesis
10% cases : isolated vaginal agenesis with an obstructed
uterus or small rudimentary uterus.
On US images, a normal uterus cannot be identified. The
ovaries often are normally situated.
On MR images, uterine agenesis and hypoplasia are best
characterized on sagittal images, while vaginal agenesis is best
demonstrated on transverse images. Agenesis results in no
identifiable uterus. Uterine hypoplasia demonstrates small uterus
with abnormal low-signal-intensity myometrium on T2-weighted
images and poorly delineated zonal anatomy.
CLASS II — UNICORNUATE (20%)
This anomaly results from complete or
near-complete arrested development of
one of the Mullerian ducts.
Four possible subtypes can
(ii) non-cavitary (non-functional)
(iii) cavitary communicating
rudimentary horn and
(iv) cavitary non-communicating
The embryologic predominance of the unicornuate uterus to be on the
RIGHT has not been explained.
• Fusiform shape : tapering
at the apex
• Draining into a solitary
• The uterus is generally
shifted off of midline
On MR images:
• Unicornuate uterus appears curved and elongated
• The external uterine contour assumes a banana shape.
• Uterine volume is reduced.
•The endometrium may be uniformly narrow or may assume a bullet
shape, tapering at the apex.
• Normal myometrial zonal anatomy is maintained.
• The endometrial-to-myometrial width and ratio are reported to be
CLASS III — DIDELPHYS (5%)
• This anomaly results from complete non-fusion of both Mullerian ducts.
• The individual horns are fully developed and almost normal in size.
• Each mullerian duct develops its own hemiuterus and cervix and
demonstrates normal zonal anatomy with a minor degree of fusion at the
level of the cervices. NO COMMUNICATION IS PRESENT BETWEEN THE
DUPLICATED ENDOMETRIAL CAVITIES.
• A longitudinal vaginal septum is associated in 75% of these anomalies .
On USG :
• Separate divergent uterine horns are identified
• With a large fundal cleft
• Endometrial cavities are uniformly separate, with no evidence of
• Some patients with uterus didelphys present with a unilateral
hemivaginal septum, which may result in obstruction with
consequent hematometrocolpos .
• Majority of cases reported in the literature are associated with
renal agenesis on the same side as the obstructing transverse
hemivaginal septum. This syndrome has been referred to as
OBSTRUCTED HEMIVAGINA–IPSILATERAL RENAL
CLASS IV — BICORNUATE (10%)
• This class is characterised by partial non-fusion of the
• This results in a central myometrium separating the uterus
that may extend to the level of the internal cervical os
(BICORNUATE UNICOLLIS) or external os (BICORNUATE
BICOLLIS). The fundal cleft is usually > 1 cm deep.
• The horns of the bicornuate uteri are not as fully developed
and are smaller than those in the didelphys uteri.
Ultrasound demonstrates two uterine horns
(arrows) and a single cervix
The horns demonstrate normal uterine zonal
anatomy. The endometrial-to-myometrial ratio and
width are normal in appearance.
CLASS V — SEPTATE (55%)
• This class of anomaly occurs when the final fibrous septum between
the two Mullerian ducts fails to resorb.
• This results in the formation of a uterus that is completely or partially
divided into two cavities.
• The septum may be muscular or fibrous or a combination of both.
• This class is associated with the poorest obstetrical outcomes. It has
been theorized that the decreased connective tissue may result in
POOR DECIDUALIZATION AND IMPLANTATION, while increased
muscular tissue may result in INCREASED CONTRACTILITY of the
tissue, thereby predisposing the patient to spontaneous abortion.
• It is important to distinguish a fibrous septum from a muscular
septum, as the former can be repaired by a hysteroscopic approach,
whereas the latter may require a transabdominal surgical approach.
US: The echogenic endometrial cavities are separated at the
fundus by the intermediate echogenicity of the myometrium and
by a hypoechoic fibrous segment caudally.
• The differentiation between a septate and bicornuate uterus is
important because they differ in their reproductive prognosis and
• Depth of
• < 1 cm
• > 1 cm
• Convex/ flat
• <75 degrees
• <4 cm
• Fibrous or
• >105 degrees
• >4 cm
CLASS VI — ARCUATE
• This group is characterised by mild indentation of the endometrium
at the uterine fundus .
• It is the result of near complete resorption of the uterovaginal
• Currently, No Definitive Depth Has Been Established To Differentiate
The Arcuate Configuration From The Septate.
• This class is highly controversial, as it remains unclear whether this
variant should be classified as a true anomaly or as an anatomic
variant of normal.
• Data regarding the reproductive outcome of patients in this category
are extremely limited and conflicting. Currently, it is generally thought
that an arcuate uterus is compatible with normal pregnancy and
CLASS VII — DIETHYLSTILBESTROL RELATED
•Several million women were treated with diethylstilbestrol (DES),
a non-steroidal oestrogen, to prevent miscarriage between 1945
and 1970 .
•The drug was promptly removed from the market when it was
foundthat up to 15% of newborn girls who were exposed to DES
had UTERINE MALFORMATIONS and an increased risk of
VAGINAL CLEAR CELL CARCINOMA .
•The uterine abnormalities include hypoplasia and a T-shaped
uterine cavity .
• Patients may also have abnormal transverse ridges,
pseudopolyps and stenoses of the cervix.
TRANSVERSE VAGINAL SEPTUM
• Defects of vertical fusion results in a transverse vaginal septum.
• It can occur anywhere along the vagina, although it occurs most
frequently at the junction of the upper and middle third.
•The septum is a membrane of fibrous connective tissue with
vascular and muscular components .
• There is resultant hematocolpos and hematometra, which is
usually less striking, secondary to decreased distensibility of the
more muscular myometrium.
UNDESCENDED AND ECTOPIC TESTES
•Undescended testis(UDT) is a common genitourinary anomaly in which
the testis fails to descend completely and is located along the normal
pathway of descent.
•Ectopia testis on the other hand is rare with an incidence of <1% of all
cases of undescended testes.
•Usg is the primary modality. However, if the testis cannot be localised
by USG MRI is used.
•The testicle is typically low signal on T1 and high signal on T2. The
normal testicle exhibits intense diffusion restriction, and these
sequences can aid confident identification.
DISORDERS OF SEXUAL
- Male pseudohermaphroditism
- Female pseudohermaphroditism
- True hermaphrodite
- Mixed gonadal dysgenesis
- Pure gonadal dysgenesis
- Persistent mullerian duct syndrome
INTERNAL MALE PSEUDO HERMAPHRODITE
Radiologic investigation continues to be one of
the most important sources of clinical information
in the evaluation of urinary and genital tract
The role of diagnostic imaging is to help
determine as closely as possible the exact nature
of the abnormality.
But the need for radiologic examinations should
be carefully weighed to avoid inconveniencing the
patient, exposing the patient to unnecessary
radiation, or delaying surgical correction.
“In the field of scientific observation,
chance favours the prepared mind”
Dr. Louis Pasteur