Kidney diagram

Renal dynamic non-imaging examination is a non-imaging examination for understanding renal function and upper urinary drainage. The most commonly used tracer is 131I-OIH. It is generally believed that in the absence of urinary tract obstruction, renal index (RI) can better reflect renal function. Normal RI ≥ 45%; 30% to 44% are mildly impaired renal function; 20% to 29% are moderately impaired; <20% are severely impaired. The renal function of normal elderly people has a natural decline. After 40 years of age, the RI value has a tendency to decrease. It should be considered when judging renal function.