Imaging of the Urinary System

Question 1

Anatomical overview

Each kidney is about ______ cm long

The kidneys are slightly ______ in men than in women

They increase in size up to the age of 20 years and become _______ again in later life

Each kidney weighs 120-170 grams

Renal blood flow ____ cc/min

Answer 1

10- 12

larger

smaller

1200

Question 2

Ureters:

______ cm long

3-8 mm in diameter

_ points of narrowing

___

______ ____

__ _______

Passes on the medial edge of ____ muscles which separate it from the tip of the transverse processes

Answer 2

25-30

3

PUJ

Pelvic brim

VU junction

psoas

Question 3

Bladder:

Pyramidal structure with its base _________ and apex behind the ________

Extra-_______

_______ is a triangular area between the ureteric and urethral orifices

Answer 3

posteriorly

symphysis

peritoneal

Trigone

Question 4

what are indications of renal imaging?

Answer 4

Renal colic and renal stone disease - Diagnosis and follow up

Hematuria

Suspected renal mass

UTIs

Hypertension

Question 5

What are different imaging techniques?

Answer 5

Plain film

Contrast studies:

• IVU
• Pyelography: antegrade, retrograde, ileal conduit
• Cystography

Ultrasound +/- contrast

CT and CTU

MR and MRU

Isotope scans

PET-CT

Question 6

what are the advantages of plain films?

Answer 6

Cheap and readily available

Functional and anatomical information (IVU)

Question 7

what are the disadvantages of plain films?

Answer 7

Low sensitivity and specificity for urological diseases

Radiation

Question 8

what is shown here?

Answer 8

KUB
Urethral stone

Question 9

What is shown here?

Answer 9

IVU
Stone left ureter

Question 10

What is shown here?

Answer 10

IVU showing bladder tumour

Question 11

what are some other contrast studies?

Answer 11

Pyelography - Injection of contrast into the ureters

Micturating cystourethrography - Vesico-ureteric reflux and its grade

Question 12

what are the advantages of US?

Answer 12

Cheap and readily available

No radiation

Contrast is not nephrotoxic

Real time imaging

Question 13

what are the disadvantages of US?

Answer 13

Limited by body habitus and gas

Poor visualisation of ureters

Operator dependant

No functional information

Question 14

what is shown here?

Answer 14

Ultrasound
normal right kidney

Question 15

what is shown here?

Answer 15

Horseshoe kidney
US and CT

Question 16

what is shown here?

Answer 16

Ureterocele

a congenital abnormality found in the ureter. In this condition the distal ureter balloons at its opening into the bladder, forming a sac-like pouch

Question 17

what is shown here?

Answer 17

Megaureter

medical anomaly whereby the ureter is abnormally dilated

Question 18

what is shown here?

Answer 18

Renal tumour

Question 19

What is shown here?

Answer 19

Urothelial tumours

Question 20

What is shown here?

Answer 20

Doppler US
Normal

Question 21

what is shown here?

Answer 21

Renal artery stenosis

Question 22

what are the advantages of CT?

Answer 22

Currently the imaging modality of choice for detection of renal stones, staging renal tumours, investigation of hematuria

Good spatial resolution with capability of multi planar reformat

Question 23

what are the disadvantages of CT?

Answer 23

Radiation dose

Cost

Contrast resolution less than MR

Contrast reaction and nephrotoxicity

Question 24

What is shown here?

Answer 24

CT
right sided renal stone

Question 25

what is shown here?

Answer 25

CT showing renal tumour with IVC thrombus

Question 26

what is shown here?

Answer 26

CT Bladder tumour

Question 27

what is shown here?

Answer 27

CTU left ureteric tumour

Question 28

what are the advantages of MR?

Answer 28

Multiplanar imaging Excellent contrast resolution Imaging of urothelium without contrast injection (MRU)

Question 29

what are the disadvantages of MR?

Answer 29

Poor spatial resolution Poor detection of calcification and stones Cost Contraindications: pace maker, claustrophobia,etc Contrast reaction and other side effects

Question 30

what is shown here?

Answer 30

Angiomyolipoma Right kidney MR

Question 31

what is shown here?

Answer 31

Tumour right kidney MR

Question 32

what is shown here?

Answer 32

MRU Duplex collecting system

Question 33

What is shown here?

Answer 33

MRU Horseshoe kidney

Question 34

What is shown here?

Answer 34

MRU transitional cell tumour

Question 35

What is shown here?

Answer 35

Bilateral renal tumours and cysts

Question 36

Isotope scan - what are each of the following used for: DMSA MAG3 Bone scan

Answer 36

DMSA - To look for renal scarring MAG3 - Assess renal function and drainage Bone scan - Metastatic disease e.g. prostate cancer

Question 37

is a PET-CT useful?

Answer 37

Limited use in staging of urological malignancies due to high uptake in urine and variable uptake by tumours May be useful for extra-urological metastatic disease if other imaging modalities are equivocal or in poor surgical candidates

Question 38

case 1: 45 year old man with right sided renal colic No hematuria No other medical problems of note What does US show? What other imaging test that you would like to request? What is your plan of management?

Answer 38

_What does US show?_ - Hydoronephrosis - Ureter not dilated. .?PUJ obstruction _What other imaging test(s) that you would like to request?_ - CT: Assess anatomy and cause of obstruction: eg stone, tumour - MAG3: Assess function - Or MR _What is your plan of management?_ - Confirm diagnosis of PUJ - Exclude an aberrant renal artery - Treatment - Interventional radiology, Surgery

Question 39

What is shown here?

Answer 39

CT angiography crossing accessory renal artery

Question 40

Case 2: 65 year old male with medically resistant hypertension and suspected renal artery stenosis. eGFR 55 ml/min What is the initial test that you would like to request? How would you plan further management?

Answer 40

_What is the initial test that you would like to request?_ - MRA - CTA - Historically US and Renal isotope _How would you plan further management?_ - Conventional angiography - Dilation and stent

Question 41

What is the best imaging modality to diagnose renal tract stones? a) Plain films b) US c) CT d) MR e) Pyelography

Answer 41

C

Question 42

What imaging modality of choice in staging of renal tumours a) US b) CT c) MR d) PET-CT

Answer 42

B

Question 43

What is the least helpful imaging modality in assessment of patient with suspected renal artery stenosis a) CTA b) MRA c) US d) Conventional angiography

Answer 43

C