Male Pelvis

Question 1

Describe the normal anatomy of the prostate.

Answer 1

Peripheral gland: peripheral zone and central zone

Central gland: central zone and transition zone

https://epos.myesr.org/posterimage/esr/ecr2020/156187/mediagallery/882705?deliveroriginal=1

Question 2

What are the indications for Prostate MRI?

Answer 2

Prostate Magnetic Resonance Imaging ( Fig. 4.28 )

Indication

• Staging of known prostate cancer
• Elevated PSA with negative biopsy
• Rising PSA in order to direct biopsy

Question 3

What is the MRI technique for Prostate imaging?

Answer 3

Technique

1. Glucagon, 1 mg IV (optional)
2. Endorectal (1.5T) or surface coil (3T)
3. Fully inflate coil
4. Avoid rotation of coil
5. Large field of view T2W imaging of pelvis/abdomen for adenopathy
6. Large field of view DWI to look for adenopathy and bony lesions
7. Small field of view T2W imaging of prostate in multiplanar views to assess for extracapsular extension and transition zone tumors
8. Small field of view DWI to assess for diffusion restriction in peripheral zone
9. Dynamic contrast-enhanced MRI to assess for perfusion, mainly to increase detection

Question 4

IVP imaging features of BPH

Answer 4

Benign Prostatic Hyperplasia (BPH)

Imaging Features ( Fig. 4.29 )

• IVP
• Bladder floor indentation
• Elevation of interureteric ridge, resulting in J-shaped ureters
• Bladder trabeculations, diverticula
• Postvoid residual urine

Intravenous urography imaging the urinary tract 15 min after contrast media infusion showing bilateral “fish-hook” ureters (→) and hydronephrosis in an 64-year old men with BPH–LUTS (a) as well as a unilateral “fish-hook” ureter (→) and elevated bladder base (*) in an 70-year old man with BPH–LUTS

https://link.springer.com/article/10.1007/s00345-010-0612-9/figures/1

Question 5

What are the imaging features of BPH on USS?

Answer 5

US

• Enlargement of central gland
• Hypoechoic or mixed echogenic nodules
• Calcifications within the central gland or surgical capsule
• Prostate volume >30 mL

Case courtesy of Dr Fakhry Mahmoud Ebouda, Radiopaedia.org, rID: 34645

Question 6

PATH

What is the pathology of BPH?

Answer 6

Pathology

Benign prostatic hyperplasia is due to a combination of stromal and glandular hyperplasia, predominantly of the transition zone (as opposed to prostate cancer which typically originates in the peripheral zone).

Androgens (DHT and testosterone) are necessary for the development of BPH but are not the direct cause for the hyperplasia.

Question 7

What are the risk factors for BPH?

Answer 7

Risk factors

• increasing age
• family history
• race: blacks > whites > Asians
• cardiovascular disease
• use of beta-blockers
• metabolic syndrome: diabetes, hypertension, obesity 8

Question 8

How do you calculate prostate volume on USS?

What is normal?

Answer 8

Ultrasound

• Ultrasound has become the standard first-line investigation after the urologist’s finger.
• there is an increase in the volume of the prostate with a calculated volume exceeding 30 mL (width x height x length x 0.52)

BPH

• the central gland is enlarged and is hypoechoic or of mixed echogenicity
• calcification may be seen both within the enlarged gland as well as in the pseudocapsule (representing compressed peripheral zone)
• post-micturition residual volume is typically elevated
• associated bladder wall hypertrophy and trabeculation due to chronically elevated filling pressures

Question 9

What is the main imaging feature of BPH on CT?

Answer 9

CT

Prostate extends above superior ramus of symphysis pubis

Case courtesy of Assoc Prof Frank Gaillard, Radiopaedia.org, rID: 35992

Question 10

What are the imaging features of BPH on MRI?

Answer 10

MRI

• Enlargement of transition zone
• Multiple circumscribed nodules (organized chaos)
• Prostate volume >30 mL
• heterogeneous signal with an intact low signal pseudocapsule in the periphery

https://epos.myesr.org/posterimage/esr/ecr2020/156187/mediagallery/882705?deliveroriginal=1