The document provides an overview of retrograde urethrography (RGU) and micturating cystourethrography (MCU), detailing their methodologies, indications, and anatomical considerations for both male and female urethras. RGU is primarily used for anterior urethral abnormalities while MCU focuses on posterior abnormalities and detection of bladder pathology. It also discusses the procedures, equipment, and potential complications associated with these diagnostic imaging techniques.

1. Retrograde Urethrography (RGU)
AND
Micturating Cystourethrography (MCU)
By
Dr. Aniket Chugh
DEPARTMENT OF RADIODIAGNOSIS
ERA’S LUCKNOW MEDICAL COLLEGE AND HOSPITAL

2. INTRODUCTION:
Urethrography refers to the radiographic study of the urethra using iodinated
contrast media and is generally carried out in males.
When the urethra is studied with instillation of contrast into the
distal/anterior urethra it has been referred to as:
 Retrograde urethrography [RGU]
 Ascending urethrography [ASU]
When the posterior urethra is studied during micturation, this has been
referred to as:
 Voiding cystourethrography [VCUG]
 Micturating cystourethrography [MCU]

3. ANATOMY OF URETHRA
• MALE URETHRA IS 18-20 cms LONG
• EXTENDS FROM BLADDER NECK TILL THE MEATAL OPENING AT PENIS
• It has four named regions:
 Prostatic urethra:
• Is approximately 3 cm in length.
• Passes through the prostate gland.
 Membranous urethra:
• Is approximately 1 cm in length.
• Passes through the urogenital diaphragm.

4.  Bulbar urethra
From inferior aspect of urogenital diaphragm to
penoscrotal junction.
 Spongy (penile) urethra:
Passes through the length of the penis.

5. PARTS OF URETHRA
 ANTERIOR URETHRA
-PENILE URETHRA
-BULBAR URETHRA
 POSTERIOR URETHRA
- MEMBRANOUS URETHRA
- PROSTATIC URETHRA

6. Female urethra :-
• In females the urethra is relatively short
• 4-5cms in length
• It begins at the neck of bladder and passes inferiorly
through the perineal membrane and muscular pelvic
floor.
• Narrowest and least distensible at meatus.
• This forms the Spinning top configuration of urethra
on normal MCU.

7. RGU/ASU vs VCUG/MCU
• RGU is carried out to visualize anterior urethral abnormalities
• MCU for posterior urethral abnormalities.
• Additionally, although the bladder is not generally the main target of the exam, as with a
cystogram, a VCUG/MCU may be useful in detection of bladder abnormalities and vesico-
ureteric reflux (VUR).
• In a trauma situation, an RGU/ASU should be performed first. A VCUG/MCU should not be
performed first because blindly trying to introduce a Foley catheter into the bladder in a
trauma setting may lead to creating additional urethral damage with the catheter

8. Retrograde/Ascending Urethrography (RGU)
Definition:
• It is retrograde demonstration of the renal pelvis and ureter by the
retrograde injection of radio-opaque material through the ureters.

9. INDICATIONS:-
• Stricture
• Urethral Trauma
• Fistulae or false passages
• Congenital abnormalities
CONTRAINDICATIONS:-
• Acute UTI
• Recent instrumentation

10. CONTRAST MEDIUM :-
- Iohexol (LOCM)
- Iopamidol (LOCM)
EQUIPMENT :-
•Tilting radiography table.
•Fluoroscopy/spot film device.
• Foley’s catheter/Infant feeding tube, Syringe, Gloves
PREPARATION :-
• Patient is asked to micturate prior to the procedure

11. TECHINIQUE :-
Preliminary film - Coned Supine AP view of Bladder Base and Urethra
• Place the patient in supine position . Retract the foreskin and clean the tip of the penis with Betadine® (povidone-
iodine) or antiseptic solution
• Inject a small amount of topical local anesthetic (e.g., lidocaine gel) into the urethra with a 8-F foley catheter or syringe
and ballon is inflated with 1-3 ml of water.
• Local anesthetic helps to relax the sphincter as the patient may contract it during the procedure thus leading to a
diagnosis of a stricture.
• The patient position should be oblique to visualize the full length of the urethra.
• Contrast medium is then injected under fluoroscopy control and films are taken.
• Gently pull the catheter to straighten the penis and prevent overlapping on the urethra.
• The male urethra is best seen in the oblique position. Female urethra is best seen in lateral or antero-posterior position.
• Ideal images demonstrate the entire length of the urethra with contrast beginning to fill the bladder.

12. •IMAGING:-
• Supine AP before injecting contrast medium.
• 30º left anterior oblique
• 30º right anterior oblique
NORMAL RETROGRADE URETHROGRAM (RGU):
• If the radio-opaque contrast is injected properly the
entire anterior and posterior urethra should be filled
with contrast and seen to jet into the bladder neck. The
verumontanum is seen as an ovoid filling defect in the
posterior urethra. The distal end of the verumontanum
marks the proximal boundary of the membranous
urethra and constitutes the urethra that passes through
the urogenital diaphragm.

13. AFTER CARE:-
1. Observation.
2. Prophylactic antibiotics
may be used
COMPLICATIONS :-
• Contrast reaction (due
to absorption through
bladder mucosa)
• UTI
• Urethral trauma.
• Extravasation of
contrast - due to use of
excessive pressure in
stricture.

14. Micturating
Cystourethrog
ram (MCU)
Voiding cystourethrogram/
Micturating
cystourethrogram
demonstrates the lower
urinary tract
Helps in detection of:
• Vesico-ureteric reflux
• Bladder pathology
• Congenital or acquired
anomalies of bladder
outflow tract.

15. INDICATIONS
Children:
1. UTI
2. Voiding difficulties like dysuria, thin stream, dribbling, frequency, urgency.
3. Vesico ureteric reflux.
4. Neurogenic dysfunction of the bladder: Meningomyelocele, Sacral agenesis.
5. For post operative evaluation of ureteric abnormalities.
6. Pelvic Trauma.
7. In renal failure to exclude reflux.
8. Boys with hematuria-MCU can demonstrate posterior urethral valve
9. Hydronephrosis and/or Hydroureter.

16. Adults
Main indications:
1. Suspected bladder/urethral trauma.
2. Suspected urethral diverticula.
3. Suspected vesicovaginal/ vesicocolic fistula.
4. Functional disorders of bladder and urethra.

17. PROCEDURE:
• Using a sterile technique, a catheter is introduced into the bladder.
• A 5f feeding tube with side holes are used for children and in older children or adults 8f or 10 f catheters
are used.
• In girls after initial inspection of perineum to identify any local genitilia abnormalities (cystoceles or labial
fusion ) the catheter is introduced.
• When it enters the bladder a varying amount of urine will flow through it .If no flow the catheter is
introduced till urine is obtained.
• Suprapubic pressure Is sometimes helpful.
• In males, foreskin is retracted, and catheter is introduced.
• The catheter should be lubricated with anaesthetic jelly and inserted slowly and gently into the urethra
holding the penis in a vertical position.
• The normal bladder capacity in children is estimated to be ~(29)cc.
• For newborns -30 to 35 cc can be instilled.
• For up to 3 yrs - 200 to 250 cc can be given.
• Adequate capacity is reached when the child becomes uncomfortable and begins voiding around the
catheter.

18. Contrast is diluted with normal saline before administration. The estimated volume of
contrast medium to be given:
Less than one year: Weight (kg) x 7 = capacity (ml)
Less than two years: (2 x age in years + 2) × 30 = capacity (ml)
More than two years:(Age in years/2 + 6) × 30 = capacity (ml)
Adult: Around 500 ml

19. Filming
In children
• During filling, fluoroscopic screening is performed at short intervals to see if vesicoureteral reflux, diverticuli
or other abnormalities are present. The child is turned oblique on both sides to ensure that minimal reflux
is not overlooked.
• If reflux appears, films are taken in the appropriate oblique projection. If the bladder appears normal, one
film is taken in the frontal projection at the end of filling.
• Voiding starts in infants the moment the catheter is removed.
• At the end of voiding, a frontal film is taken which includes entire abdomen including the kidney region in
order to prevent overlooking the vesicoureteral reflux which is apparent only on termination of voiding and
may reach the upper collecting system.

20. In Adult Male :
• Bladder is filled in the usual way as in older child and voiding filming is done in both oblique
projection views.
• The voiding study in male adults can be modified by getting the patient to void against resistance
i.e., by compression of distal part of penis or using penile clamp thus enhancing the visualization
of urethra by artificial distention. This is known as CHOKE CYSTOURETHROGRAPHY
In Adult Female:
• The procedure is essentially the same
• In addition to the standard exposures, a double exposed film taken at rest and during straining
demonstrates the degree of bladder descent if any.

21. Filming Technique:
Scout film:
• The first image that is taken while performing the MCU and VCUG is the image of KUB that
is called scout film. We evaluate the spine, pelvis, and soft tissues on the scout film.
• After several seconds of the contrast media begins to flow, the image of minimally filled
bladder is taken in Antero-posterior (AP) projection.
• During early filling a ureterocele or tumor can be detected
and it may obscure as more contrast material enters
into the bladder.

22. Voiding phase
• The image taken during voiding may
demonstrate the urethral strictures or
obstructions.
• They will also give the details of the presence or
absence of vesicoureteral reflux.
• Voiding film is necessary because it gives the
determination of reflux because reflux may only
happen with the pressure generated by voiding.
NORMAL MCU
(IN MALES)
NORMAL MCU
(IN FEMALES)

23. Post-voiding film
• A post-voiding film may demonstrate
the reflux or extravasation of urine from
the bladder or urethra.
• A normal post-void film has no reflux
and no residual urine.

24. COMPLICATIONS
• Contrast reaction.
• Contrast induced cystitis.
• UTI.
• Catheter trauma.
• Bladder perforation - overfilling.
• Retention of a foley catheter.
• Catheterization of vagina / ectopic ureter.
• Radiation exposure

26. Vesicoureteric reflux (VUR) grading according to the
height of reflux up the ureters and degree of
dilatation of the ureters:
• Grade 1: reflux limited to the ureter
• Grade 2: reflux up to the renal pelvis
• Grade 3: mild dilatation of ureter and
pelvicalyceal system
• Grade 4
• tortuous ureter with moderate dilatation
• blunting of fornices but preserved papillary
impressions
• Grade 5
• tortuous ureter with severe dilatation of
ureter and pelvicalyceal system
• loss of fornices and papillary impressions

27. GRADE-III GRADE-IV GRADE- V

28. POSTERIOR URETHRAL VALVE
IN NEWBORN
POSTERIOR URETHRAL VALVE
IN 7 YEARS OLD
Transverse filling defect in the posterior urethra

29. HUTCH DIVERTICULUM NEUROGENIC BLADDER

30. Limitations of conventional RGU combined with voiding
cystouretherography:
1. It does not provide accurate length of the defect because of poor prostatic
urethral filling.
2. It does not provide information regarding extent of fibrosis of corpora spongiosa
or prostatic displacement.
3. The stricture length is overestimated if bladder neck does not relax.

31. Advantages of CT urethrography
1. C.T. voiding uretherography is more comfortable to the patient
because it requires adaptation only in one position.
2. Less time consuming; takes only few seconds
3. Comparison of luminal size & stricture length for follow up is possible.
4. Extraluminal pathology can be detected
5. Good patient compliance
6. Ability to survey whole urinary tract from kidney to urethra

32. THANK YOU