<prompt> Investigation of choice for evaluating a renal mass is -Plain X-rayCT scanIVPRenal scintigraphy  <response>: Ans. is b i.e., CT scan Computed Tomography is still the investigation of for evaluating and characterizing solid renal masses. -Grainger 6theImportant investigations in genitor-urinary systemo Investigation of choice for renal and ureteric stones - non - contrast spiralo Most commonly used investigation to diagnose urinary tract obstruction- USG.o Most commonly used initial investigation of urinary tract malignancies kidney, bladder - USGo Investigation of choice for diagnosis and staging of RCC - contrast - enhanced CTo Investigation of choice to detect I VC and renal vein involvement in RCC - MRI 1st choice, Doppler USG 2nd choiceo Investigation of choice for hydronephrosis - USGo Investigation of choice for vesicourethral reflex - voiding micturating cystourethrogramo Investigation of choice for posterior urethral valve - voiding micturating cystourethrogramo Best method to visualize posterior urethra - voiding cystourethrogram.o Investigation of choice for pyonephrosis - USG 