Study Of Contrast-enhanced Ultrasound In Rabbits With Acute Renal Failure Model

Objectives: 1.To assess the value of the gray scale contrast-enhanced ultrasound (CEUS) in evaluation of the renal cortical and medullary perfusion changes in the early time in rabbits with acute renal failure (ARF) model.2. To discuss the correlationship of the renal cortical blood perfusion changes showed by the gray scale CEUS and the blood serum creatinine (SCr),the blood urea nitrogen(BUN) in rabbits in development of ARF. Methods: 34 rabbits ARF models established with intramuscular 50% glycerin (12-15 ml/kg) injection into rabbits'thighs. The gray scale CEUS was performed on the day before injection(T₀) and the day1,4,8,12 after injection(T₁,T₄,T₈,T₁₂). The renal contex and medulla perfusion time-intensity curve(TIC) was analyzed , the parameters including: AT(arrival time),TTP (time to peak intensity), A(amplitude of peak intensity), AUC (area under the curve),β(slope rate of TIC). Meanwhile the SCr,BUN were measured before the CEUS examination.1. 17 rabbits for example, analyzed the parameters T0 and T₁ TIC of renal contex and medulla, in order to assess the value of CEUS in evaluation of the renal cortical and medullary perfusion changes in the early time in rabbits with acute renal failure (ARF) model. 17 rabbits were executed and their kidneys were sent to Pathology examination.2.For analyzing the correlationship of the renal cortical blood perfusion changes showed by the gray scale CEUS and the blood serum creatinine (SCr),the blood urea nitrogen(BUN) in rabbits in development of ARF, The rest 17 rabbits were going on experiment after injection(T₄,T₈,T₁₂).Results: 1. The value of A andβof renal cortex at T0 was (17.36±13.73)dB and (5.38±2.08)dB/s, respectively, the value of A andβof renal cortex at T1 was (6.59±4.25)dB and (1.58±1.41)dB/s, respectively, A andβof renal cortex before model establishment was both significantly higher than those after 1d model establishment (P<0.05). The value of TTP and AUC of renal cortex at T0 was (2.46±1.76) s and (329.31±171.70) dBs, respectively, The value of TTP and AUC of renal cortex at T1 (5.93±4.80) s and (722.28±354.14) dBs, respectively, TTP and AUC of renal cortex before model establishment was both significantly lower than those after 1d model establishment (P<0.05). At T₀ the value of AT of renal cortex and medulla was (6.83±3.11) s and (8.25±3.00) s, respectively, the value of A, TTP, AUC,βof renal medulla was (8.98±7.40) dB,(8.69±11.22) s,(360.79±210.90) dBs and (4.85±5.32) dB/s, respectively, the value of SCr or BUN was (57.33±10.18)μmol/L and (7.75±2.11) mmol/L. At T₁ the value of AT of renal cortex and medulla was(7.87±3.39) s and (8.35±3.89) s, respectively, the value of A, TTP, AUC,βof renal medulla was (1.70±6.16) dB,(7.93±11.04) s,(459.59±612.50) dBs and (3.86±3.46) dB/s, respectively, the value of SCr or BUN was (89.54±30.12)μmol/L and (10.78±1.56) mmol/L. No significant difference was found in AT of renal cortex, AT, A, TTP, AUC,βof renal medulla and SCr or BUN before and after 1d model establishment.2. At T₁,T₄,T₈,T₁₂, the value of TTP (5.93±4.80) s,(13.86±4.03) s,(13.45±3.63) s,(7.16±3.45) s, respectively, the value of A (13.26±27.40) dB,(5.06±2.77) dB,(6.71±1.43) dB,(10.06±2.19) dB, respectively, the value ofβ(1.58±1.41) dB/s, (1.13±0.89) dB/s, (1.66±0.74) dB/s, (2.33±0.99) dB/s, respectively, the value of TTP,A andβat T₀ (2.46±1.76) s,(17.36±13.73)dB,(5.38±2.88) dB/s, the value of TTP at T₁,T₄,T₈ was significantly longer than the value of at T0, (P<0.05), the value of A andβat T₁,T₄,T₈ was significantly lower than the value of at T0, (P<0.05), the value of TTP,A andβat T₁₂ was no significant difference than the value of at T₀. And the differences between T₁,T₄ and T₈ were not the same.It is showed that AT,TTP,A,βhad no correlation with neither SCr (r = 0.20,-0.08,-0.31,-0.09,respectively, P>0.05) nor BUN (r = 0.11,-0.11,-0.24,0.05,respectively, P>0.05).Conclusions: 1. CEUS can display the changes of perfusion image of the renal cortex of the early time ARF model earlier than SCr and BUN.2. The variation trend of the parameters of CEUS was that TTP make longer, A andβmake lower in development of ARF, but there have no liner relationship between the blood perfusion parameters and SCr,BUN.