Genitourinary System: Normal Imaging Patterns

Genital urinary system

Presentation outlines

Introduction to the genital urinary system

• Genital urinary system anatomical organs(general)
• Genital urinary system anatomical organs to be investigated with contrast
• Types of contrast media

Indications of contrasted imaging procedures of the genital urinary system

Genitourinary system

• The genitourinary system includes organs of both the urinary and reproductive systems.

The urinary system consists of the kidneys, ureters, bladder, and urethra.

The reproductive system includes the testes, vas deferens, seminal vesicles, prostate gland, penis (in males), and ovaries, fallopian tubes, uterus, cervix, and vagina (in females)

Introduction……

Urinary tract is the system consisting of kidney, ureters, Urinary bladder and urethra which is responsible for excretion of waste products in form of urine .

• Upper urinary tract is made up of two kidneys and two ureters

Lower urinary tract is made up of Urinary bladder and urethra

Functions of Urinary System organs:

• Kidneys: Filter waste from the blood and produce urine.
• Ureters: Tubes that carry urine from the kidneys to the bladder.
• Bladder: Stores urine until it is eliminated from the body.

Urethra: Tube that carries urine from the bladder to the outside of the body.

Reproductive System:

• Male:
• Testes: Produce sperm and hormones.
• Vas Deferens: Tube that carries sperm from the testes.
• Seminal Vesicles: Produce a fluid that nourishes and supports sperm.
• Prostate Gland: Produces fluid that is part of semen.

Penis: Organ of sexual intercourse.

Female:

• Ovaries: Produce eggs and hormones.
• Fallopian Tubes: Carry eggs from the ovaries to the uterus.
• Uterus: Where a fetus develops during pregnancy.
• Cervix: Lower, narrow part of the uterus.

Vagina: Canal that connects the cervix to the outside of the body.

Anatomical organs of the genital urinary system to be investigated with contrast

Urinary System:

Kidneys:

These are the primary organs for filtering blood and producing urine. Imaging with contrast can help visualize kidney size, shape, and identify abnormalities like tumors or blockages.

Ureters:

These tubes carry urine from the kidneys to the bladder. Contrast imaging can help assess for blockages or narrowing of the ureters.

Bladder:

This organ stores urine. Contrast imaging can help evaluate the bladder's shape, size, and capacity, as well as identify any abnormalities like tumors or diverticula.

Urethra:

This tube carries urine from the bladder out of the body. Contrast imaging can help assess for blockages, strictures, or other abnormalities in the urethra.

Male Reproductive System:

Prostate:

This gland surrounds the urethra and produces fluid that is part of semen. Contrast imaging can help assess its size, shape, and identify any abnormalities like tumors or enlargement.

Seminal Vesicles:

These glands produce a fluid that makes up a portion of semen. Contrast imaging can help assess their size and shape and identify any abnormalities.

Female Reproductive System:

Uterus:

This organ is where a fetus develops during pregnancy. Contrast imaging can help visualize the uterus's shape and identify abnormalities like fibroids or polyps.

Fallopian Tubes:

These tubes connect the ovaries to the uterus. Contrast imaging can help assess for blockages or other abnormalities.

Contrast media

Contrast types for genital urinary system investigation

For imaging the genitourinary system, contrast agents are used to enhance visualization of the kidneys, ureters, bladder, and urethra.

These agents can be broadly categorized as positive and negative contrast, with positive contrast being further divided into water-soluble iodinated contrast and barium.

Positive Contrast Agents:

Water-soluble iodinated contrast media:

These are the most common type used for intravenous urography (IVU) and CT urograms. They are injected intravenously and allow visualization of the kidneys, ureters, and bladder as they are excreted.

Ionic vs. Non-ionic: Ionic contrast agents have a higher incidence of side effects due to their hypertonicity but are becoming less common due to the availability of non-ionic agents.

Non-ionic agents: Examples include iopamidol, iohexol, iodixanol, and iotrolan. These are generally preferred due to lower incidence of side effects.

NOTE:

Barium: Barium is contraindicated for use in the urinary tract due to potential complications if extravasation occurs.

Negative Contrast Agents:

Room air, CO2, or N2O: These are used for double-contrast cystography to visualize the bladder. Air is the most common but CO2 and N2O are considered safer due to their higher solubility.

Contrast Imaging Procedures and indications of each procedure

• Radiological investigations used for imaging of the genital urinary tract
• Plain radiology(KUB)
• Intravenous urography
• Retrograde pyelography and cystography
• Urethrography

Hysterosalpingography

1: PLAIN URINANARY TRACT RADIOGRAPHY(KUB)

• This is when radiograph of the abdomen is used to evaluate the urinary tract
• Most common finding will be in from of calcification
• Disadvantages

Poor sensitivity and specificity regarding urinary tract calcifications Sensitivity be limited by small size of the stones, low density composition of the stone, or when there is overlapping stool, bone structures, or air which may obscure the stones

Renal stones

• radiopaque
• Calcium oxalate dihydrate
• Calcium oxalate monohydrate
• Calcium phosphate
• radioluscent
• Uric acid
• Ammonium urete
• Indinavir

xanthine

AP and lateral lumbar X-ray

2:Intravenous Urography( IVU)/ Excretory Urogram (EU)

Intravenous Urogram (IVU) is the x ray examination of the kidney, Ureter and urinary bladder by injecting iodinated contrast materials into the veins.

Contrast used is sodium diatrizoate (urografin) or meglumine iothalamate and is used so as to highlight the urinary system The contrast is given through peripheral veins, oral or Rectally It involves use of low-osmolar and non-ionic contrast agents (half life of contrast is 4hrs with almost complete clearance by 24hrs) A dose of up to 1.five mg/ kg can be well tolerated

Indications of IVU/EU

Kidney pattern of secretion and ureters obstruction e.g. Hydronephrosis due to the presence of the renal stone Hematuria or pyuria

• Renal colic or flunk pain
• Suspected renal injury
• To ascess renal function
• Renal tumors

Post surgery for urinary leak, fistulae and stricture

Contraindications

• Iodine sensitivity
• Hepatorenal syndrome
• Pregnancy
• Renal failure
• Multiple myeloma
• Thyrotoxicosis

Hypergammaglobulinemias

Normal intravenous Urogram

3:RETROGRADE PYELOGRAPHY AND CYSTOGRAPHY

This involve Direct injection of water-soluble iodinated contrast material into the ureter The advantage of this method of evaluation is the direct control over the contrast injection rather than reliance on secondary excretion from the kidney Retrograde pyelography, often carried out in conjunction with cystoscopy, is performed by placing a small catheter into the distal ureter. Contrast material is then injected through this catheter into one or both ureters.

Retrograde Pyelography:

• Indications:
• Evaluation of ureteral obstruction.
• Identification of filling defects like stones or tumors.
• Assistance with percutaneous access for procedures like stent placement.
• Assessment of hematuria or trauma.
• Characterization of ureteral or pelvicalyceal abnormalities seen on other imaging.
• Contraindications:
• Active urinary tract infection.
• Pregnancy (due to radiation exposure).
• Allergy or sensitivity to contrast agents, local anesthesia, iodine, or latex.
• Severe kidney failure or other severe kidney problems.

May be relatively contraindicated in cases of severe coagulopathy.

Cystography (including VCUG):

• Indications:
• Diagnosis of vesicoureteral reflux (VUR).
• Evaluation of bladder or urethral abnormalities.
• Assessment of bladder rupture or injury.
• Contraindications:
• Active urinary tract infection (UTI).
• Pregnancy (due to radiation exposure).
• Allergy or sensitivity to contrast medium.

May be relatively contraindicated in cases of severe coagulopathy.

4:URETHROGRAPHY

Refers to the radiographic study of the urethra using iodinated contrast media and is generally carried out in males Types/ classification of Urethrography When the urethra is studied with instillation of contrast into the distal/anterior urethra it has been referred to as:

• Retrograde urethrography (RUG) or

Ascending urethrography (ASU)

Types cont.…..

• When the posterior urethra is studied during micturition, this has been referred to as:
• Voiding cystourethrography (VCUG) or
• Descending urethrography or

Micturating urethrography

Indications of urethrography

• pelvic trauma in the emergency department (retrograde only)
• diminished urinary stream
• urethral strictures
• urethral diverticula
• urethral obstruction
• suspected urethral foreign bodies
• urethral mucosal tumors
• Floating prostate on digital rectal examination

suspected urethral fistula

5. HYSTEROSALPINGOGRAM (HSG)

Hysterosalpingogram is a commonly performed imaging investigation in cases of infertility.

A cannula or catheter is placed within the cervical canal and 10-20ml of contrast injected to outline the uterine cavity and tubes. Fluoroscopy is usually used if available. The examination is best performed around day 10 of the cycle when tubal filling is most likely to occur.

In practice this can seldom be achieved and it is performed anytime within the first half of the cycle after menstruation has ceased and before the time of fertilisation.

Indications for hysterosalpingogram:

• Recurrent abortion – ?Uterine abnormality
• Congenital abnormality (bicornuate uterus; unicornuate uterus)
• Acquired abnormality (fibroids, cavity adhesions (aschermans syndrome)
• Infertility – ? tubal occlusion
• Contraindications:
• Pregnancy
• Infection
• Menstruation

Complications:

Venous intravasation: this is a common problem. May be due to too forceful injection or performing the examination too soon after menstruation Infection – especially cross infection if instruments are not sterilised properly between patients Pain – this can be severe on spillage of the dye into the peritoneal cavity, occasionally causing fainting

Normal radiographic findings of the genital urinary system

Kidneys

Shape & Size: Typically, kidneys are bean-shaped, measuring approximately 9–14 cm in length, with a smooth outline.

The renal pelvis, calyces, and medulla should be clearly visible, without any evidence of filling defects, masses, or obstructions Contrast Enhancement: In contrast studies, the renal cortex enhances uniformly, while the medulla appears darker.

Imaging Phases:

• Nephrogram Phase: Immediately after contrast injection, a "renal blush" is observed.
• Excretory Phase: 3–5 minutes post-injection, the renal calyces and pelvis become visible.

Delayed Phase: 9–13 minutes later, the contrast moves into the ureters and bladder.

Ureters:

Appearance: Ureters are visualized as thin, tubular structures extending from the renal pelvis to the bladder.

Function: They transport contrast from the renal pelvis to the bladder, often requiring delayed imaging to assess.

• They follow a fairly straight course, with slight curves as they approach the bladder.
• The ureters should be free of any narrowing, dilation, or filling defects.

Normal ureters are thin-walled and may not always be visible unless filled with contrast

Urinary Bladder:

The bladder appears as a distended, oval-shaped structure filled with contrast media and with a smooth inner surface.

• The ureteral openings into the bladder should be visible and symmetrical.

The bladder wall should appear thin and uniform.

Post-Void Imaging: A post-micturition X-ray is often taken to ensure the bladder is empty and to identify any residual contrast or abnormalities It should not show any filling defects, wall irregularities, or signs of reflux (backflow of urine into the ureters).

Urethra:

The male urethra is visualized as a tubular structure extending from the bladder neck to the external urethral meatus.(The prostatic urethra is visualized as a thin, linear structure, with the verumontanum appearing as a central, ovoid filling defect) The female urethra is shorter and more difficult to visualize on contrast studies.

Both should appear as a single, continuous channel, without any obstructions or irregularities.

Retrograde Urethrogram: This imaging technique involves introducing contrast into the urethra to visualize its structure.

Normal Findings: The urethra should appear patent without strictures or obstructions.

NOTE: The male urethra is divided into three parts: the prostatic urethra, the membranous urethra, and the penile urethra.

The prostatic urethra, located within the prostate gland, is typically the widest part and is characterized by the presence of the verumontanum, a ridge-like structure.

The membranous urethra is the shortest segment, located between the prostate and the penis.

The penile urethra runs through the corpus spongiosum of the penis and is visualized as a thin, linear structure.

Uterus and Fallopian Tubes:

Hysterosalpingography (HSG): A contrast study used to evaluate the uterus and fallopian tubes.

Normal Findings:

Uterus: Typically, the uterus should have a smooth contour without irregularities.

Fallopian Tubes: The contrast should fill the tubes and spill into the peritoneal cavity, indicating patency. The fallopian tubes appear as thin, curved structures extending from the uterine horns.

NOTE: In a normal HSG, the contrast dye should flow smoothly through the uterus and both fallopian tubes, spilling into the pelvic cavity.

They should be free of any masses, adhesions, or obstructions.

Normal findings in these studies include proper filling and emptying of the bladder, normal ureteral peristalsis, and absence of reflux A hysterosalpingogram (HSG) is an X-ray procedure used to visualize the uterus and fallopian tubes, primarily to assess their patency (whether they are open) and the shape of the uterine cavity. It's a common test for women experiencing infertility or recurrent miscarriages.

Organ/System

Normal Imaging Characteristics

• Kidneys
• Smooth, bean-shaped; uniform contrast enhancement; prompt excretion
• Ureters
• Thin-walled; contrast-filled; visible in delayed imaging
• Bladder
• Centrally located; smooth outline; thin, smooth wall
• Urethra
• Patent; no strictures or obstructions

Uterus & Tubes

• Uterus with smooth contour; tubes filled with contrast; peritoneal spill

Summary of Normal Imaging Findings

Abnormal radiographic findings of the genital urinary system

Kidney

Example of Congenital anomalies of the urinary sytem

• Horseshoe kidney
• Duplex kidney and bifida ureter
• Polycystic kidney disease
• Retrocaval ureter
• Ureterocele (intracystic ballooning of the dilated ureter)

Posterior Urethral Valve

Kidney Anomalies

Renal Agenesis: Absence of one or both kidneys.

Renal Hypoplasia: Abnormally small kidneys(where there is essentially normal residual parenchyma but smaller calyces, lobules and papillae).

Renal Dysplasia: Abnormal formation of the kidneys.

Horseshoe Kidney: Kidneys joined together, forming a horseshoe shape.(kidneys fused at the lower poles) Renal Ectopia: Kidneys in abnormal positions.

Renal Malrotation: Kidneys not rotated properly.

Renal Agenesis

refers to a congenital absence of one or both kidneys. If bilateral (traditionally known as the classic Potter syndrome) the condition is fatal, whereas if unilateral, patients can have a normal life expectancy Radiographic features:

Absence of one or both kidneys. On X-ray, the affected side will show no kidney shadow, and the contralateral kidney may be enlarged or show signs of compensatory hypertrophy.

• Associations
• Renal agenesis can be associated with a number of chromosomal abnormalities including:
• trisomy 21
• other fetal trisomies
• trisomy 22
• trisomy 7
• trisomy 10
• 45X mosaicism
• Turner syndrome
• 22q11 microdeletion

Clinical presentation

If renal agenesis is unilateral and isolated then patients are asymptomatic. Unless identified on antenatal screening, then it is found incidentally when the abdomen is imaged for other reasons. Occasionally patients with unilateral renal agenesis, develop secondary hypertension.

Those with bilateral renal agenesis often have additional birth defects, both associated with, and a result of the absence of kidneys. With no kidneys, the fetus is unable to produce urine, which is necessary to form amniotic fluid resulting in anhydramnios. As a result, severe oligemia is present with the main resultant abnormality being pulmonary hypoplasia.

Summary in Renal Agenesis findings

Absent Kidney: The affected kidney's fossa will appear empty, as there is no kidney to fill with contrast.

Compensatory Enlargement: The remaining kidney will show contrast enhancement and likely appear larger than normal due to increased workload.

Absent Ureter: The ureter on the affected side will also be absent, as it arises from the kidney's development.

Fluoroscopy Procedure:

During an intravenous pyelogram (IVP), the contrast medium is injected into a vein, and fluoroscopy allows real-time visualization as the contrast travels through the kidneys, ureters, and bladder.

Diagnosis:

The absence of contrast filling in the renal fossa, combined with the other findings, helps confirm the diagnosis of renal agenesis.

Horseshoe Kidney:

Fusion of the lower poles of the kidneys, often with abnormal positioning and rotation. The kidneys may be lower than normal and appear connected across the midline.

• Radiographic findings:

Fluoroscopy

On intravenous urography (IVU), the control/scout film will show a soft tissue mass on either side of the midline with a central isthmus. The kidneys are also oriented with the lower pole closest to the midline, which is the reverse of normal.

Following intravenous contrast, the orientation of the pelvicalyceal system is clearly outlined and may illustrate associated complications such as a PUJ obstruction.

Visualised as a fused kidney with an abnormal orientation and lower pole location, often connected by an isthmus at the lower end.

The contrast medium outlines the pelvicalyceal system, revealing the HK's atypical anatomy and any associated complications like obstruction or hydronephrosis.

Horseshoe kidneys are the most common type of renal fusion anomaly. They render the kidneys susceptible to trauma and are an independent risk factor for the development of renal calculi and transitional cell carcinoma of the renal pelvis

HORSE SHOES

Horseshoe Kidney

Scout films demonstrate a U-shaped soft-tissue mass across the midline (isthmus connecting lower poles).

Kidneys have lower-positioned, medially oriented lower poles, closer to the spine.

After contrast: the pelvicalyceal systems form the classic “hand-holding calyces” or “flower‑vase” sign—calyces appear to reach across midline The ureters pass anterior to the isthmus and renal pelvis

Genitourinary System: Normal Imaging Patterns

ON THE IMAGE : Multiple variable-sized hyperdense foci compatible with urinary tract calculi indicate an unusually medial position of the lower poles of both kidneys

Renal hypoplasia

A small, underfilled kidney that nonetheless shows normal calyceal and pelvic architecture.

On excretory urography: prolonged—but present—contrast excretion with reduced size of pelvicalyceal system.

The scarred or atrophic kidney excretes contrast slowly but normally in morphology

Renal Ectopia (Simple & Crossed)

Simple ectopic kidney: the contrast-filled kidney appears in an unexpected location (e.g., pelvis, iliac region, thorax).

Crossed fused ectopia: both kidneys and collecting systems appear on the same side of the spine on IVU. The ectopic kidney's ureter still enters the bladder on the ipsilateral side.

Scout: absence in renal fossa; contrast phase: no activity there, but functioning ectopic kidney visualized elsewhere.

Renal Malrotation

On contrast IVU: the renal pelvis and calyces appear abnormally oriented—commonly anterior-facing or in lateral positions instead of medial.

• Variations seen:
• Anterior pelvis—classic non-rotation.
• Lateral/reverse pelvis—reverse rotation.
• Hyperrotation—extreme rotation (over 180°).

Sagittal orientation—rare cases where hilum faces superiorly or inferiorly

Summary

• Condition
• IVU/Fluoroscopy Findings

Renal Agenesis

• Absent renal shadow + hypertrophy of contralateral kidney; no artery present

Renal Hypoplasia

• Small kidney with preserved structure and delayed contrast excretion

Renal Dysplasia

• “Silent” kidney; irregular/absent pelvicalyceal architecture; possible cystic outlines

Horseshoe Kidney

Midline isthmus on scout; medially oriented lower poles; “hand‑holding” / “flower-vase” calyces

Renal Ectopia

• Kidney appears off-position; crossed variant shows both kidneys on same side

Renal Malrotation

Abnormal orientation of pelvis/calyces—anterior, lateral, hyperrotated, or sagittal

Collecting System Anomalies

Hydronephrosis: Enlargement of the renal pelvis and calyces due to urine backup.

Ureteropelvic Junction (UPJ) Obstruction: Blockage at the connection between the renal pelvis and ureter.

• Megacalycosis: Enlarged calyces (renal collecting system) without obstruction.

Duplex Collecting System: Presence of two separate collecting systems within one kidney.

Collecting System Anomalies

Hydronephrosis

On IVP/fluoroscopy after contrast injection:

Delayed, dilated renal pelvis and calyces (pelvicalyceal system) with thinning of the calyceal walls.

In moderate‑to‑severe cases, you see uniform calyceal outline, “ballooned” appearance, and a distended pelvis—sometimes forming an extrarenal pelvis.

Delayed drainage: contrast remains in pelvis/calyces longer than normal.

Hydronephrosis (plural: hydronephroses) is defined as dilatation of the urinary collecting system of the kidney (the calyces, the infundibula, and the pelvis The term hydroureteronephrosis (or hydronephroureterosis) may be used when the dilatation occurs in the presence of hydroureter.

Radiographic features

Following the identification of hydronephrosis, appropriate further investigations must be undertaken to establish an underlying cause, such as urolithiasis, pelviureteric junction obstruction, malignancy such as cervical cancer, and retroperitoneal fibrosis.

Genitourinary System: Normal Imaging Patterns

The grading system of hydronephrosis developed by the Society of Fetal Urology (SFU) was devised to assess the degree of hydronephrosis.

• Classification
• grade 0
• no dilatation, calyceal walls are opposed to each other

grade 1 (mild)

dilatation of the renal pelvis without dilatation of the calyces (can also occur in the extrarenal pelvis) no parenchymal atrophy

• grade 2 (mild)
• dilatation of the renal pelvis (mild) and calyces (pelvicalyceal pattern is retained)
• no parenchymal atrophy
• grade 3 (moderate)
• moderate dilatation of the renal pelvis and calyces
• blunting of fornices and flattening of papillae
• mild cortical thinning may be seen
• grade 4 (severe)
• gross dilatation of the renal pelvis and calyces, which appear ballooned
• loss of borders between the renal pelvis and calyces
• renal atrophy seen as cortical thinning
• grade 4 (severe)
• gross dilatation of the renal pelvis and calyces, which appear ballooned
• loss of borders between the renal pelvis and calyces

renal atrophy seen as cortical thinning

Megacalycosis

Enlarged calyces that are uniformly dilated with rounded/semilunar shapes; number of calyces may be increased.

• Renal pelvis and ureter are normal calibre (no dilation).
• On IVP: numerous faceted calyces, normal pelvis/ureter, and normal washout

Faceted having many sides

Duplex Collecting System

On excretory urography (IVP/fluoroscopy):

Visualization of two separate collecting systems and ureters (complete or incomplete duplication).

A hypofunctioning moiety may not excrete contrast; the other may show a “drooping lily” sign—lower pole displaced and wrapped around non-functioning upper pole.

May see ureterocele at the bladder, reflux into lower pole, or ectopic insertion of upper pole ureter Fluoroscopy

Excretory urography (IVP)

Although able to elegantly image both collecting systems, one should be aware that a poorly functioning system may not excrete contrast. In such a situation, the functioning lower pole moiety will be inferiorly displaced, taking on the so-called "drooping lily appearance" 1. The differential for such an appearance is that of an upper pole mass or cyst.

Genitourinary System: Normal Imaging Patterns

Left sided duplicated collecting system with a distorted lower pole moiety from obstructed upper pole. This results in the so-called drooping lily sign

Ureteropelvic Junction (UPJ) Obstruction

Marked dilation of the renal pelvis with calyces appearing distended, but ureter remains non-dilated (“hydronephrosis without hydroureter”).

• On dynamic/multi-phase contrast studies:
• Normal early nephrogram, but delayed filling and drainage of pelvis/calyces.
• “Swirling” of contrast or fluid‑levels in collecting system.
• In obstructed kidneys: often a large extrarenal pelvis, atrophic pyramids.
• swirling

move in a twisting or spiralling pattern

SUMMARY

• Condition
• Pelvis
• Calyces
• Ureter

Key Fluoro Signs

• Hydronephrosis
• Dilated
• Dilated, uniform
• ± Dilated
• Ballooning, delayed contrast drainage
• UPJ Obstruction
• Dilated
• Not dilated
• Extrarenal pelvis, delayed flow, swirling contrast
• Megacalycosis
• Normal
• Enlarged, multiple
• Normal
• Numerous, faceted calyces; normal drainage

Duplex Collecting System

• 1–2 pelves
• 2 separate systems
• 1–2 ureters

Double collecting systems; drooping lily sign; ureterocele

Ureter Anomalies

• Megaureter: Abnormally dilated ureter.
• Ectopic Ureter: Ureter opening in an abnormal location.
• Ureterocele: A bulge in the ureter, often at the bladder entrance.

Vesicoureteral Reflux (VUR): Backflow of urine from the bladder into the ureters.

Megaureter

Definition: Ureter > 7–8 mm in diameter Fluoroscopy (IVU/retrograde pyelography): Uniform, marked ureteral dilation (“megaureter”), sometimes bilateral; narrowing often seen near the ureterovesical junction in primary obstructive cases

Ectopic Ureter

Ureter draining to an abnormal location (e.g., bladder neck, urethra, vagina) IVU: Aberrant ureteral course, may show distal drainage outside normal trigone; often associated with duplex kidney

Intravenous urography (IVU)

It can detect abnormal ureteral insertion and associated anomalies e.g. renal duplication. In complete duplex kidney and ureter, the ectopic ureter usually drains the upper moiety and associated with ureterocele and obstruction.

Voiding cystourethrogram

Usually, the ectopic ureter is associated with vesicoureteric reflux, which can be detected and graded with VCUG.

An ectopic ureter is identified and inserted into the posterior urethra. Associated grade III vesico-ureteric reflux is also noted

Ureterocele

Radiographic findings

Cystic dilation of the distal ureter within (orthotopic) or outside (ectopic) the bladder trigone, often in duplex systems VCUG: Well-defined filling defect early in filling (“cobra‑head” radiolucency surrounded by contrast halo); may evert or prolapse Ureteroceles represent abnormal congenital dilatation of the distal-most portion of the ureter. The dilated portion of the ureter may herniate into the bladder secondary to the abnormal structure of vesicoureteric junction (VUJ)

Fluoroscopy

• IVP

Detectable findings include:

filling defect in the bladder (cobra head sign) which may be distended, collapsed or even everted radiolucent halo effect

• an everted ureterocele will appear like a bladder diverticulum
• Voiding cystourethrogram may show:
• a round or oval lucency near the trigone

there may be effacement of the defect with increasing filling of the bladder

Cobra head sign

Vesicoureteral Reflux (VUR):

Retrograde flow of urine from the bladder back into the ureters and potentially into the kidneys.

This is typically diagnosed using voiding cystourethrography (VCUG) which involves filling the bladder with contrast and taking X-rays while the patient urinates.

VCUG (Fluoroscopy): Contrast seen flowing up the ureter to the renal pelvis; reflux graded I–V based on extent and dilatation

Prune Belly Syndrome:

Characterized by a deficiency of abdominal wall musculature, cryptorchidism, and urinary tract abnormalities, including dilated ureters and a dilated prostatic urethra. X-rays may show a wrinkled appearance of the abdomen, and other imaging may reveal the dilated urinary tract.

summary

Megaureter: Prominent ureteral dilation distal to UVJ; narrowed segment if obstructive.

Ectopic Ureter: Aberrant distal course on IVU/urography; may show associated hydronephrosis or ureterocele.

Ureterocele: “Cobra‑head” sign on IVU/VCUG; distinct filling defect in bladder.

VUR: Graded retrograde contrast flow on VCUG; may accompany other anomalies like duplex systems or ureterocele.

Bladder and Urethra Anomalies

Posterior Urethral Valves (PUV): Obstructive flaps of tissue in the urethra, almost exclusively in males.

• Bladder Exstrophy: A birth defect where the bladder develops outside the body.

Epispadias: A birth defect where the urethra opens on the upper side of the penis.

Posterior Urethral Valves (PUV)

On VCUG/fluoroscopy:

Dilated posterior urethra (“keyhole” or pine‑cone appearance) due to obstructing valve flaps.

• Linear radiolucent band representing the valve in the distal posterior urethra .
• Hypertrophied bladder neck and trabeculated thick‑walled bladder, often with diverticula.
• Vesicoureteral reflux (VUR) in ~50% of cases, ranging from mild to severe
• Upper tract changes on IVU include bilateral hydroureteronephrosis, renal dysplasia.

Retrograde urethrogram (RUG): abrupt stop of contrast at valve site in bulbar urethra

Common congenital anomalies of genital system

Common congenital anomalies of the uterus and fallopian tubes that can be visualized with fluoroscopic X-ray (hysterosalpingogram or HSG) include uterine abnormalities like A bicornuate uterus (a heart-shaped uterus) Septate uterus (a uterus divided by a wall), unicornuate uterus (a uterus with only one side developed).

Fallopian tube abnormalities like blockage and hydrosalpinx (fluid-filled tubes) can also be identified

Uterine Anomalies

• Unicornuate uterus

Appearance: Banana- or fusiform-shaped single uterine cavity with lateral deviation; contrast flows through a single fallopian tube A small, rudimentary horn may sometimes be visualised if it communicates.

• Uterus didelphys

Appearance: Two distinct uterine cavities and cervices; HSG shows two separate tubes and contrast catheters.

• Strong lateral divergence of horns.
• Bicornuate uterus

Appearance: Heart-shaped or indented fundus with two symmetric horns; intercornual angle > 105° Fallopian tubes opacify each horn.

4. Septate uterus

Appearance: Smooth external fundal contour; internal septum divides cavity. On HSG, contrast outlines two cavities with an indented septum; outer shape remains normal

• Arcuate uterus
• Appearance: Mild fundal indentation (<1 cm); subtle saddle-shaped cavity seen on HSG
• T‑shaped uterus (DES exposure)

Appearance: Narrowed, T-shaped cavity in the Fundus due to in utero DES exposure; seen on specialized HSG

Genitourinary System: Normal Imaging Patterns

A T-shaped uterus refers to a specific radiographic appearance of the endometrial cavity and is classified as a class VII Müllerian duct anomaly. It is the most commonly associated abnormality from in utero DES exposure Diethylstilbestrol (DES) is a synthetic estrogen that was prescribed to pregnant women from the 1940s to 1971 to prevent miscarriages.

Fallopian Tube Anomalies

• Accessory fallopian tubes

Rare duplication or bifurcation seen as secondary contrast-filled outpouchings from the tube

• Unilateral absence of the tube
• Commonly associated with a unicornuate uterus; only one tube is visualized on HSG
• Undescended fallopian tubes

Tubes positioned abnormally high (e.g., up to iliac vessels); HSG shows elongated tubes with contrast spill high in pelvis

Traumatic Injuries of Genitourinary system

• Bladder Rupture

X-ray Cystography (fluoroscopy):

Intraperitoneal rupture: Contrast outlines bowel loops or mesentery (“contrast between loops”) following dome injury Extraperitoneal rupture: Contrast pooling around bladder in perivesical / pelvic tissues Irregular bladder contour or disruption

• Urethral Injury
• Retrograde urethrogram (fluoroscopy):
• Contrast extravasation from the urethra (posterior or anterior)
• Disruption or discontinuity of the urethral contour
• Inability of contrast to pass into the bladder (complete disruption)
• Common causes: Pelvic fracture (posterior urethra), straddle injury (anterior urethra
• Shows contrast extravasation at injury site (e.g., membranous or bulbar urethra)

with loss of continuity or abnormal pooling; often preceded by blood at the meatus

3. Ureteral Trauma

IVP / Retrograde pyelogram:

Contrast leak into perirenal or retroperitoneal space; non‑opacification of ureteral segment or hydronephrosis indicates transection or injury.

• Renal Injury

Although CT is preferred, plain-film IVP may show delayed contrast excretion, perinephric collection/hematoma, or cortical contour irregularities.

• Modality: Intravenous pyelogram (IVP), less commonly used now
• Findings:
• Delayed nephrogram or non-visualization of a kidney (vascular injury)
• Contrast extravasation from the collecting system
• Irregular renal outline (laceration)

Perinephric contrast collection

5. Testicular / Penile Trauma

Fluoroscopy rarely used. Plain X-ray/Ultrasound preferred:

Ultrasound identifies tunical tear and hematoma in testicular rupture; penile fracture diagnosed clinically and via ultrasound, sometimes cavernosography

Infertility pathologies

Primary study: Hysterosalpingography (HSG) Performed under fluoroscopy with contrast injection into the uterine cavity via the cervix.

Provides detailed images of the uterine cavity and fallopian tubes

Tubal Pathologies and their radiographic findings

Tubal occlusion (complete/nonspasm partial): No contrast beyond a point—mid‑segment block most common Hydrosalpinx: Dilated tube filled with contrast, often distal pooling—major negative predictor for pregnancy.

Peritubal adhesions/salpingitis isthmica nodosa/ampullary diverticula: Irregular mucosal outline, “beaded” or “pipe-stem,” diverticula outpouchings.

Peritoneal spill: Absence suggests distal obstruction; irregular spill suggests adhesions.

Tubular obstruction

Tubular obstruction, or occlusion, in a hysterosalpingogram (HSG) indicates a blockage in the fallopian tubes, preventing the passage of contrast dye during the procedure.

This blockage can be a significant factor in female infertility as it hinders the meeting of sperm and egg, thus preventing fertilization.

Causes of Tubal Obstruction:

Infections: Pelvic inflammatory disease (PID) is a major cause of tubal damage and blockage.

Endometriosis: Endometrial tissue outside the uterus can lead to adhesions and blockages.

Scarring: Previous surgeries, ectopic pregnancies, or other inflammatory conditions can cause scarring that blocks the tubes.

Congenital Abnormalities: In rare cases, structural abnormalities present at birth can cause tubal obstruction.

Salpingitis Isthmica Nodosa (SIN): A condition characterized by nodular thickening of the isthmic portion of the fallopian tube, potentially leading to obstruction.

Fibroids or Polyps: Growths in the uterus or fallopian tubes can physically block the passage.

Spasm: Sometimes, the tubes may spasm during the HSG procedure, mimicking a blockage. This is often temporary.

RADIOGRAPHIC FEATURES IN THE HSG

No spill: The most obvious finding is the lack of contrast dye spilling into the abdominal cavity, indicating a blockage.

Proximal obstruction: Blockage near the uterus at the utero-tubal junction.

Distal obstruction: Blockage at the fimbrial end of the tube, sometimes leading to hydrosalpinx (fluid-filled tube).

Unilateral or bilateral: Blockage can be on one or both side

Radiographic findings

Absence of Contrast Spillage

A primary indicator of fallopian tube obstruction is the failure of contrast medium to spill into the peritoneal cavity during HSG. This suggests a blockage, preventing the contrast from passing through the tubes.

Hydrosalpinx

Hydrosalpinx is characterized by the dilation of the fallopian tube due to fluid accumulation. On HSG, this appears as a dilated, elongated tube filled with contrast, often without any spill into the peritoneum, indicating distal tubal obstruction

Corkscrew or Beaded Appearance

Chronic inflammation, such as from pelvic inflammatory disease, can cause the fallopian tubes to develop a corkscrew or beaded appearance. This is due to alternating areas of narrowing and dilation along the tube, visible on HSG .

Peritubal Adhesions

Adhesions surrounding the fallopian tubes can restrict their movement and function. On HSG, peritubal adhesions may manifest as loculated contrast spill or a halo sign, indicating areas where the contrast is trapped due to surrounding scarring.

Tubal Spasm

Temporary tubal spasm can mimic obstruction on HSG. This is often differentiated by administering antispasmodic agents and observing for resolution of the spasm, allowing for accurate assessment of tubal patency.

Tubal spasm refers to a transient, involuntary contraction of the fallopian tube's smooth muscle, which can mimic a true mechanical obstruction during HSG. This spasm can lead to the temporary absence of contrast flow into the peritoneal cavity, suggesting a blockage that may not actually be present.

Hydrosalpinx

• Hydrosalpinx, a condition where the fallopian tubes are blocked and filled with fluid.

Normal HSG:

In a normal HSG, the dye injected into the uterus flows freely through the fallopian tubes and spills into the abdominal cavity, indicating open and healthy tubes.

RADIOGRAPHIC FEATURES

Absence of dye spillage into the peritoneal cavity and the Visualization of a distended, fluid-filled tube, often described as sausage-shaped or retort-like.

The HSG helps diagnose hydrosalpinx by revealing this blockage and fluid accumulation.

Salpingitis isthmica nodosa

Salpingitis isthmica nodosa (SIN) is a condition where the isthmic portion of the fallopian tube (the narrow part connecting to the uterus) develops nodular thickening, sometimes described as diverticulosis of the fallopian tube.

• It's often associated with infertility and ectopic pregnancy.

"full of knots

RADIOGRAPHIC FINDINGS:

The hysterosalpingogram (HSG), an X-ray procedure using contrast dye injected into the uterus and tubes, is the primary method for diagnosing SIN.

Diverticula: The most characteristic finding is the presence of multiple small, sac-like outpouchings (diverticula) of the fallopian tube wall, filled with contrast medium.

Honeycomb Appearance: These diverticula often create a "honeycomb" appearance on the HSG, indicating the nodular thickening and diverticular changes of SIN.

Note : Rosary bead" appearance” is named also in chronic salpingitis Salpingitis Isthmica Nodosa (SIN) is characterized on hysterosalpingography (HSG) by multiple small diverticula in the fallopian tubes, often appearing as a "honeycomb" pattern. These diverticula, which are pockets of contrast medium, are in continuity with the tubal lumen and located in the periluminal tissue. The HSG findings are crucial for diagnosing SIN, which is linked to infertility and ectopic pregnancy.

Pathology

• Radiographic Features (HSG)
• Tubal obstruction
• No spillage of contrast into peritoneal cavity
• Blockage at cornua, mid-tube, or fimbrial end
• Hydrosalpinx
• Dilated, tortuous, or sausage-shaped fallopian tube
• "Beaded" appearance
• Delayed emptying of contrast
• Salpingitis isthmica nodosa
• Multiple small outpouchings or diverticula along fallopian tubes
• "Rosary bead" appearance
• Uterine septum (septate uterus)
• Narrow, elongated endometrial cavity
• Central filling defect with sharp angle (<75°)
• Bicornuate uterus
• Two symmetric horns with a wide angle between them (>105°)
• Often seen as two endometrial cavities
• Arcuate uterus
• Mild indentation of the uterine fundus
• Smooth contour, broad angle between horns
• Asherman’s syndrome (intrauterine adhesions)
• Irregular filling defects or non-filling regions
• Narrowed or obliterated endometrial cavity
• Submucosal fibroid / polyp
• Smooth filling defect within the uterine cavity
• May displace contrast
• Congenital uterine agenesis or hypoplasia
• Non-visualization or underdeveloped uterine cavity

FEMALE INFERTILITY PATHOLOGIES & RADIOGRAPHIC FINDINGS (HSG)

Acquired pathologies of the genital urinary system

Nephrolithiasis & Ureterolithiasis (Kidney/Ureter Stones)

Means are Mineral concretions in the kidney/ureter causing pain and potential obstruction.

X-rays can detect the presence and location of kidney stones, particularly if they are calcified.

X‑ray (KUB):

Calcium stones (oxalate/phosphate, struvite) appear radiopaque (white) in 70–90% of cases Uric acid, cystine, and drug-induced stones are often radiolucent (invisible) Radiographic appearance varies: dense “hard” for calcium phosphate, “mulberry” for calcium oxalate, branching “stag‑horn” for struvite Fluoroscopy (IV urography): Filling defects along ureters or within collecting systems; delayed contrast passage if obstruction exists Secondary signs: Urinary tract dilation—hydronephrosis/hydroureter—visible on fluoroscopy or plain film (soft‑tissue shadows) Urolithiasis refers to the presence of calculi anywhere along the course of the urinary tracts struvite stones are more frequently encountered in women

Urolithiasis refers to the presence of calculi anywhere along the course of the urinary tracts.

For the purpose of the article, the terms urolithiasis, nephrolithiasis, and renal/kidney stones are used interchangeably, although some authors have slightly varying definitions of each By far the most common stone is calcium oxalate, however, the exact distribution of stones depends on the population and associated metabolic abnormalities (e.g. struvite stones are more frequently encountered in women, like urinary tract infection as more common) Struvite stones, also known as infection or triple phosphate stones, are a type of kidney stone primarily composed of magnesium ammonium phosphate and carbonate apatite. They are strongly associated with urinary tract infections (UTIs) caused by urease-producing bacteria Clinical presentation

Although some renal stones remain asymptomatic, most will result in pain. Small stones that arise in the kidney are more likely to pass into the ureter where they may result in renal colic. Hematuria, although common, may be absent in approximately 15% of patients

The more common composition of stones include (more detail below):

• calcium oxalate +/- calcium phosphate: ~75%
• struvite (triple phosphate): 15%
• pure calcium phosphate: 5-7%
• uric acid: 5-8%
• Risk factors
• Certain risk factors have been identified including 8:
• low fluid intake
• urinary tract malformations:
• horseshoe kidney
• duplex collecting system

urinary tract infection

Radiographic features

• Plain radiograph
• Calcium-containing stones are radiopaque:
• Calcium oxalate +/- calcium phosphate
• Struvite (triple phosphate) – usually opaque but variable
• Pure calcium phosphate

Cystine stones

Lucent stones include:

• Uric acid
• Medication (indinavir is best known) stones

Pure matrix stones (although may have a radiodense rim or centre)

Fluoroscopy

Intravenous urography (IVU) is a traditional radiographic study of the renal parenchyma, pelvicalyceal system, ureters, and the urinary bladder. It involves the administration of intravenous contrast.

Renal (Urinary) Stone Disease

• Hard mineral deposits (calculi) form within the kidney or ureter.

Radiological Features:

Plain X-ray (KUB): Most calculi are radio-opaque and appear as bright white spots; staghorn stones fill the collecting system Fluoroscopy/IVP: Stones show up as filling defects and may cause delayed contrast passage.

1. Renal/Ureteral Stones (Urolithiasis)

Formation of mineral calculi (most often calcium oxalate/phosphate) within the kidney or ureter.

Radiographic Features:

Radio-opaque density on KUB—most calcium-based stones appear bright white Staghorn appearance—branching opacities conforming to the renal collecting system.seen on plain Localization along ureteric course (e.g., over sacrum)—suggestive of ureteric calculi .

• Filling defects on IVU—contrast voids at stone site, often with upstream dilation.

Delayed contrast excretion or hydronephrosis proximal to obstruction

Staghorn appearance

2. Nephrocalcinosis

• Diffuse deposition of calcium salts in the renal parenchyma (either medulla or cortex).

Radiological Features:

• Plain X-ray: Multiple fine calcifications in pyramids (medullary) or cortical regions

IVP/Fluoroscopy: Shrunken renal outlines, uneven contrast uptake in affected areas.

2. Nephrocalcinosis

Diffuse calcification within the renal parenchyma (medullary or cortical), often related to metabolic disorders.

Radiographic Features:

• Multiple fine calcifications within renal pyramids or cortex on KUB
• Medullary pattern—pyramidal calcifications, often bilateral
• Cortical involvement—peripheral calcifications in cortical disease patterns .

Patchy or mottled contrast uptake on IVU—due to calcified parenchymal interference

3. Genitourinary Tuberculosis

• Mycobacterium tuberculosis infects renal parenchyma, calyces, ureter, and/or bladder.

Radiological Features:

Fluoroscopic Urography (IVP): Papillary necrosis, beading of calyces and ureters, calyceal deformities, uneven caliectasis "signet ring" calcifications in calyces.

Plain X-ray: Dystrophic renal calcification: “putty kidney” (dense calcified kidney), bladder wall calcifications in chronic cases

3. Genitourinary Tuberculosis

• Mycobacterium tuberculosis infection of the urinary tract (kidneys, ureters, bladder).

Radiographic Features:

• Papillary necrosis—blunted, moth-eaten calyces visible on IVU .
• Infundibular strictures and beaded ureters—irregular ureteral outline on IVU .
• Renal calcification (“putty” or lobar) on plain film .

Thimble bladder—small-capacity flow with irregular filling on cystogram

4. Urinary Tract Schistosomiasis

• Chronic parasitic infection (Schistosoma haematobium) affecting bladder and ureters.

Radiological Features:

• Fluoroscopy/IVU: Distal ureteral dilatation and strictures; persistent filling of ureters

Plain X-ray: Fine linear calcifications of bladder wall and ureters—highly suggestive

4. Renal Fungal Infections (e.g. Candidiasis/Mycetoma)

Opportunistic infections (often fungal), forming fungal “balls” within the collecting system.

Radiographic Features:

• Filling defects on IVU due to fungal balls (mycetoma)
• Hydronephrosis—secondary to fungal obstruction .
• Papillary necrosis—due to infection-induced ischemia

Ureteral scalloping—submucosal edema evident on contrast studies

5. Renal Abscess & Emphysematous Infections

Renal abscess: Focal pus-filled cavity in kidney parenchyma from infection.

Emphysematous pyelonephritis/pyelitis: Severe gas-forming infection in renal tissue or collecting system.

Radiological Features:

• Plain X-ray/Fluoroscopy: Limited role—mass effect or gas may be seen faintly.
• Better seen on CT, but on X-ray:
• Renal abscess: Wedge‑shaped opacity, occasionally a cavity.

Emphysematous infection: Gas lucencies visible in renal region or collecting system

Summary

• Pathology
• Meaning
• X‑ray Features
• Fluoroscopy/IVP Findings
• Stone disease
• Mineral calculi in urinary tract
• Bright white calcifications; staghorn appearance
• Filling defects; delayed contrast migration
• Nephrocalcinosis
• Calcium deposits in renal tissue
• Multiple tiny calcifications in pyramids/cortex
• Patchy contrast distribution; parenchymal loss
• Genitourinary TB
• Tuberculous infection of GU tract
• Calyceal/renal calcifications; “putty kidney”
• Beading, papillary necrosis, uneven caliectasis, infundibular stenoses
• Schistosomiasis
• Parasitic bladder/ureter fibrosis
• Linear calcifications along bladder/ureters
• Persistent distal ureter filling, strictures, hydroureteronephrosis
• Renal abscess / emphysematous
• Pus/gas in collecting system/parenchyma
• Mass effect; gas lucencies

Diagnostic mainly via CT; gas may appear faintly on X-ray

Neoplasia pathologies of the genital urinary system

1. Renal Cell Carcinoma (RCC)

• Malignant tumor arising from renal tubular epithelium; most common adult kidney cancer.

Radiologic Features:

• Mass effect on IVU—displacement or distortion of the collecting system.
• Filling defects—a space-occupying lesion that displaces contrast on urography.
• Occult calcification—seen on plain film in some tumors (5–10%), often faint
• Nonfunctioning kidney—less or delayed contrast excretion from the affected side.

Staghorn/conglomerate appearance—rare but may show coarse calcification in large tumors

2. Transitional (Urothelial) Cell Carcinoma (TCC)

• Malignancy of urothelium affecting bladder, ureter, or renal pelvis.

Radiologic Features:

Filling defects on IVU—papillary/nodular projections into contrast-filled lumen.

Ureteral/renal pelvis lesion—soft-tissue mass in collecting system visible on contrast study Hydronephrosis—upstream dilation from obstruction.

Intratumoral calcification—punctate calcification occasionally seen (e.g., renal pelvis TCC).

Cortical irregularity—if invasive, may disrupt normal parenchymal outline .

3. Wilms Tumor (Nephroblastoma)

• Childhood renal malignancy, primarily affecting ages 1–5.

Radiologic Features:

• Complex renal mass—large, heterogeneous opacity displacing normal kidney silhouette
• Internal calcifications in ~5–10%—seen as amorphous densities on X‑ray.
• Displaced collecting system—collecting structures shifted or obscured on IVU .
• Nonfunctional kidney—little or no contrast excretion from the affected side.

Retroperitoneal mass effect—evident even on plain abdominal film.

4. Rhabdomyosarcoma (Genitourinary Tract)

Malignant skeletal muscle tumor, most commonly in bladder, prostate, vaginal, or paratesticular region in children.

Radiologic Features (Fluoroscopy/Cystography):

• Filling defect within bladder or urethra—mass protruding into the lumen
• Irregular bladder outline—mass alters normal shape on contrast study
• Mass effect—deformity or compression of adjacent structures.
• Possible hydronephrosis—if ureteral or bladder outlet obstructed.

Diffuse or polypoid appearance—depending on subtype; botryoid forms appear grape-like .

5. Bladder Carcinoma – Squamous Cell Type (Subtype of bladder carcinoma)

Malignancy of bladder epithelium; often related to chronic inflammation, schistosomiasis, or stones.

Radiologic Features:

• Filling defects on cystography/IVU—sessile or papillary masses within bladder contrast .
• Irregular bladder wall contour—thickening or spiculated margins.
• Reduced bladder capacity—due to wall infiltration and fibrosis.
• Calcifications—possible bladder wall calcification if chronic or necrotic.

Adjacent hydronephrosis—possible unilateral due to ureteric involvement

References

• Radiology for undergraduates and general practitioners
• Radiopedia.org
• UpToDate

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