The investigation of choice for Renal scarring defect in infected kidney is:
DMSA (99mTc-dimerruptosuccinic acid) scan: the most sensitive test for detection of acute pyelonephritis and renal scarring. It is best delayed for 4-6 months after acute infection to distinguish acute parenchymal defects from renal scars. Ref: Clinical Pediatric Urology By A. Barry Belman, Lowell R. King, Stephen Alan Kramer, 2002, Page 287
DMSA scan
DTPA
DEXA
MCU