MRI Urogram Pregnancy Renal Stone Imaging — ESENeph MCQ

Instant feedback + full explanation. One question, done properly.

ModeratePregnancy & RenalMRI Urogram Pregnancy Renal Stone ImagingESENeph

A 31-year-old woman presents with severe flank pain, nausea, and a 4 mm ureteric stone at the left PUJ on CT KUB. She is 10 weeks pregnant. Analgesia with paracetamol has been inadequate. What imaging modality should be used for follow-up if the stone does not pass spontaneously?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — MRI urogram (without gadolinium)

In pregnancy, ionising radiation should be minimised. MRI urogram (without gadolinium — gadolinium crosses the placenta and is contraindicated in pregnancy) is the preferred second-line imaging modality after ultrasound for renal tract assessment. It provides excellent soft tissue contrast, can identify ureteric obstruction (hydroureter, hydronephrosis), and can visualise the stone location. CT KUB involves ionising radiation and should be avoided in the first trimester if possible. IVU also involves radiation and iodinated contrast. Ultrasound is first-line but may miss ureteric stones. MRI can distinguish physiological hydronephrosis of pregnancy from pathological obstruction.

Reference: EAU 2023 – Urolithiasis Guidelines; NICE 2019 – NG133 Pregnancy; RCOG 2019 – Imaging in Pregnancy