Imaging

Question 1

What does absence of psoas shadow on abdominal xray indicate?

Answer 1

Retroperitoneal pathology: abscess, haematoma or tumour

Question 2

What is an intravenous pyelogram?

Answer 2

= excretory urogram
• iv contrast injected into renal paryenchaema
• pyelocaliceal system, ureters and bladder visualised

Question 3

Name 3 indications excretory urogram

Answer 3

= intravenous pyelogram
. Haematuria (can also do US).
• urolithiasis to plan therapy (but uncontrasted spiral CT investigation of choice)
• suspected renal injury

Question 4

What is a retrograde pyelogram?

Answer 4

Opacification of ureter and pyelocaliceal system by retrograde injection of contrast through ureteric catheter
Not used much, cystoscope preferred.

Question 5

What is an ascending cystogram?

Answer 5

Retrograde filling of bladder through urethral catheter

Question 6

Name 2 indications ascending cystogram

Answer 6

• Suspected bladder rupture after abdominal trauma

* assessment of bladder diverticulum

Question 7

What is a micturating / voiding cystourethrogram?

Answer 7

• Bladder filled to capacity with contrast through urethral catheter
. Radio graphic screening while voiding
• gives anatomical information about bladder and urethra, especially male posterior urethra. Detects vesicoureteric reflux

Question 8

Name 5 indications micturating / voiding cystourethrogram

Answer 8

• Suspected posterior urethral valves male infant
• evaluation neuropathic bladder
• exclude vesico-ureteric reflux
• evaluation female incontinence
• suspected urethral diverticulum females

Question 9

What is a urethrogram? Name 2 types

Answer 9

• Done in males
• ascending (retrograde) urethrogram = information about anterior (penile and bulbar) urethra
• descending (antegrade/prograde) urethrogram = info about posterior urethra (prostatic and membranous) - bladder filled via suprapubic cystostomy catheter
• in traumatic membranous urethra injuries, combined simultaneous ascending and descending urethrogram needed

Question 10

Name 4 indication urethrogram

Answer 10

Male:
• urethra trauma
•urethra strictures
• suspected urethra diverticulum
•urethra fistula

Question 11

What is a renal angiogram/ arteriogram and how is it performed?

Answer 11

• Thin catheter inserted into femoral artery, up aorta, and contrast injected here or renal arteries (selective renal angiography)
Not really used as diagnostic tool as very invasive, rather therapeutic.

Question 12

Name 2 indications renal angiogram / arteriogram

Answer 12

• Therapeutic: renal angioplasty, embolize traumatic av fistula, palliative embolization kidney for advanced RCC
• evaluate renal vascular anatomy only where non-invasive tests not available: pre-op assess living related renal donors, prior to nephron-sparing surgery in RCC

Question 13

Which MRI contrast agent is used for MR urography?

Answer 13

Gadolinium- non-nephrotoxic and non- allergenic

Question 14

What is radio-isotope scintigraphy? Name 3 types

Answer 14

• Renal scintigraphy/renogram/ renal scintigram:
• DTPA: measure glomerular filtration only
• mag 3: agent of choice. Glomerular filtration and tubular secretion
• DMSA: renal cortical morphology

Question 15

Name 6 indications radio-isotope scintigraphy

Answer 15

• Measure perfusion: GFR kidney post transplant, testicular blood flow suspected torsion
• renal function: useful for PUJO
• diagnose upper urinary tract obstruction (usually PUJ ):use iv furosemide for diuresis renogram
. Renal cortical imaging (dmsa): confirm acute pyelonephritis, diagnose renal scarring
• diagnose VUR: indirect or direct cystogram
• diagnose bone metastasis (bone scan) using radiolabeled phosphate. Especially usefull in prostate cancer.

Question 16

What is uroflowmetry?

Answer 16

• Type of urodynamic study that evaluate bladder emptying function
• need to be combined with other parameters like residual volume to make diagnosis bladder outflow obstruction
• patient void into flowmeter

Question 17

Name 7 indications Doppler ultrasound

Answer 17

• Kidneys: size, location, hydronephrosis, renal mass solid or cystic, renal pelvic filling defects calculus (acoustic shadow) VS tumour, renal inflammatory disease (abscess), renal surveillance eg screen for polycystic, facilitate percutaneous procedures (percutaneous nephrostomy, biopsy) , demonstrate arterial and venous lesions
• adrenals: infants and children, do CT for adults.
• ureter: dilation, ureteroceles in bladder, calculi at PUJ or ureterovesical junction
• bladder: masses, diverticula, measure residual urine, guide to insert percutaneous suprapubic cystostomy
• prostate TRUS: biopsy guide, brachytherapy
• seminal vesicle TRUS: local invasion by prostate cancer, investigate infertility
• scrotum: diagnose all conditions! Esp torsion.

Question 18

Simple cyst VS solid mass features on u/s? (3)

Answer 18

• Uniform round border with thin wall us irregular, poorly circumscribed border
• No internal echoes, hypoechoic (dark) VS internal echoes or variable echogenicity, hyper-echoic light)
• Posterior wall signal enhancement vs none.