Genitourinary and Gynecologic Imaging
Core concepts
Know renal anatomy and the imaging of renal masses: simple cyst (Bosniak I) versus complex cysts (Bosniak II–IV) and the features that drive management. Understand renal cell carcinoma subtypes and the role of multiphasic CT/MRI. Learn the imaging of urolithiasis (non-contrast CT, stone size and location predicting passage) and obstruction (hydronephrosis, delayed nephrogram). Understand bladder cancer staging and the role of cystoscopy. For the prostate, know zonal anatomy and the PI-RADS system. For gynecology, understand the uterus, ovaries, and adnexa; distinguish simple from complex ovarian cysts; know the imaging features of endometriosis, fibroids, and ovarian torsion. Learn the staging of cervical and endometrial cancer. Understand the adrenal incidentaloma workup (lipid-rich adenoma, washout).
Traps
Bosniak classification depends on septation, calcification, and enhancement - do not overcall a simple cyst. Ovarian torsion may show a normal-sized ovary with reduced enhancement; do not rely on size alone. Distinguish a hemorrhagic cyst from an endometrioma. Remember that a lipid-poor adenoma may not show washout. Do not confuse physiologic hydronephrosis of pregnancy with obstruction.
Rule of thumb
For adnexal masses, apply the simple rules (benign versus malignant features). A unilocular cyst under 5 cm with no solid component is almost always benign and can be followed.