MRI Urography (MR Urography)

There are three main types of urography, each using different imaging techniques to evaluate the urinary tract (kidneys, ureters, bladder):

1. X-ray :- (IVU) / Intravenous Pyelography (IVP)

2. CT Urography :- Contrast: Iodinated contrast

3. MRI :- MRI Urography (MRU)

1. Intravenous Urography (IVU) / Intravenous Pyelography (IVP)

🔹 Modality: X-ray
🔹 Contrast: Iodinated contrast injected IV
🔹 Use: 

• Classic method to evaluate kidney anatomy and function

• Detects stones, strictures, hydronephrosis
  🔹 ⚠️ Involves radiation and iodine contrast

2. CT Urography

🔹 Modality: CT Scan
🔹 Contrast: Iodinated contrast
🔹 Use:

• Excellent for detecting stones, tumors, hematuria causes

• Provides cross-sectional and 3D imaging
  🔹 ⚠️ Higher radiation dose

3. MRI Urography (MRU)

🔹 Modality: MRI
🔹 Contrast: Gadolinium (optional)
🔹 Use:

• No radiation

• Ideal for children, pregnant women, renal dysfunction

• Excellent soft tissue contrast, useful in tumors, anomalies
  🔹 🔹 Two types:
    - Static-fluid MRU (T2-weighted, no contrast)
    - Excretory MRU (T1-weighted with gadolinium)

•  Summary Table:

Type	Modality	Contrast Used	Radiation	Key Use Case
IVU / IVP	X-ray	Iodinated IV	Yes	Basic urinary tract evaluation
CT Urography	CT	Iodinated IV	High	Tumors, hematuria, stones
MRI Urography	MRI	Gadolinium (or none)	No	Pediatric, renal function, anomalies

MRI Urography non Contrast

 

•    MRI Urography (MR Urography)

Magnetic Resonance Urography (MRU) is a non-invasive imaging technique that uses MRI technology to visualize the kidneys, ureters, and bladder without radiation exposure.

Why MRI Urography is Done

MR Urography helps in evaluating:

1. Congenital anomalies – e.g., horseshoe kidney, duplex system

2. Obstruction – e.g., UPJ obstruction, ureteral stricture

3. Hydronephrosis – to assess cause and severity

4. Ureteric lesions – strictures, tumors, or calculi

5. Urinary tract infections (recurrent)

6. Post-surgical assessment – for ureteric reconstructions

7. Masses or tumors – of the kidney, ureter, or bladder

8. Vesicoureteral reflux (VUR) – indirectly seen

9. Renal function – with contrast-enhanced excretory phase

Types of MRI Urography

1. Static-fluid MR Urography

   • Heavily T2-weighted images

   • Good for dilated collecting systems

   • No contrast needed

2. Excretory MR Urography

   • T1-weighted post-contrast images

   • Evaluates renal function and excretion

   • Requires gadolinium contrast

Preparation

• Fasting 4–6 hours (for contrast studies)

• Adequate hydration

• Bladder filling may be needed for optimal visualization

• Check renal function (eGFR) before contrast use

Contraindications

• Renal impairment (eGFR <30) for contrast studies

• Implanted metallic devices not MRI-safe

• Claustrophobia (managed with sedation if needed)