The Study On Diagnosis Of Diabetic Nephropathy Using Color Doppler Ultrasound

Object:The purpose of this study was to use color Doppler ultrasound imaging to exam normal adults and patients with type 2 diabetes mellitus. To measure their kidney size, internal structure, the distribution of renal blood flow, pulse Doppler blood flow parameters of renal arteries at all levels.And to do statistical analysis, in order to provide reference values for further study of diabetic nephropathy in renal artery blood flow parameters at all levels. Under the premise of the patients being informed consent,parts of diabetic patients from the observation were selected to be done percutaneous ultrasound-guided renal biopsy and to extract meaningful renal pathology specimens, the specimens were collected from light and(or) immunofluorescence pathological examination. Then to make correlation analysis between resistance index of their all levels renal arterial and their renal histopathological stages. To discusse the clinical value of color Doppler ultrasound examination in early diagnosis and course development of diabetic nephropathy, and to guide the treatment of diabetic nephropathy, aimed at providing a more objective, quantitative technical methods for clinical non-invasive evaluation of the pathological changes of diabetic nephropathy.Methods: 20 cases of normal adults, including 11 males and 9 females, aged 45 to 72 years old, with an average age of 58.55±7.65. Diabetic group, 60 cases were type 2 DM, including men 36 cases, female 24 cases, aged 47 to 75 years old, with an average age of 60.77±7.00. According to the difference of 24-hour urinary albumin excretion rate (UAER) , the diabetic group was divided into different stages of 20 patients in each group: GroupⅠ: UAER<30mg, as normal proteinuria stage; GroupⅡ: UAER at 30~300mg, as albumin stage, the early DN; GroupⅢ: UAER > 300mg, as clinical proteinuria stage. Using of PHILIPS-IU22-mode color Doppler ultrasound instrument to measure the renal volume of normal adult group and patients with diabetic nephropathy, to classify their renal parenchymal changes, to grade the distribution of renal blood flow, to measure their color pulsed Dopple blood flow velocity index (Vsmax, Vdmin, RI). Parts of patients with diabetic nephropathy were done percutaneous ultrasound-guided renal biopsy, then to stage their pathological the extent of damage.Results:1 The kidney length (L), width (W), thickness(T) and volume (V) of patients with diabetes mellitus were more major than those in the normal control group kidneys (p<0.05).2 Normal adult renal cortex was from the outer of the renal parenchyma inward extending to area between renal pyramid, echo uniform. The echo of their renal cortex was uniform, equal to or slightly lower than the echo of the liver or spleen. Echo of renal medulla was below the cortex. Renal pyramid was triangle weak echo with the top cone pointing to the renal sinus. The demarcation of renal cortex and medulla is clear. Under Two-dimensional ultrsound(2D) imaging, it is observed that renal parenchymal echo between each group with diabetes and normal was insufficiency same (p<0.05). Renal parenchymal echo of diabetes patients with the normal proteinuria and normal adults were not significantly different (p>0.05). Renal parenchymal echo of patients with early clinical stages of DN and patients with proteinuria had statistical difference from renal parenchyma of normal adults classification (p<0.05).3 The normal adults kidney had abundant color flow signals under the color Doppler flow imaging (CDFI), it can be seen that the capsule filled with tiny blood vessels. And being able to clearly detect renal artery blood flow signal progressively distributed from the main renal artery (MRA) to segmental renal arteries (SRA), to interlobular renal artery (IRA), to arch renal artery (ARA), to small interlobular renal arteries(SIRA), which just formed a "dendritic" distribution of color flow images. The renal artery blood flow distribution of the majority of GroupⅠpatients and the normal adult had no significant difference, both could be able to detect rich blood flow signals, and both could display their MRA in the renal hilum, and SRA whose various levels branches at the formation of renal sinus were occupied throughout the distribution, and both could display IRA as short strip flow signal on both sides of the renal pyramid, as well as ARA which showed the junction point or a small bow-shaped distribution of blood flow signals was distributed between renal cortex and medulla. There are a few patients of groupⅠcan be observed the local defects of network in subcapsular vascular, color Doppler signals can not reach under the capsule. Renal blood flow signals of early stage DN patients in groupⅡwas rich, MRA, SRA was clearly visible, but the IRA blood flow signals in some patients were with uneven thickness, and parts of groupⅡpatients'ARA blood flow signal had reduced, and parts of groupⅡpatients'interlobular artery blood flow signal detection unclear. Renal blood flow signals had been presented with atypical of the "dendritic" distribution. The renal blood flow signal of DN patients in groupⅢhad reduced. The MRA was clearly still visible under CDFI, but the renal artery blood flow signals were not continuous, with varying thickness, The blood flow signal of some IRA and ARA was unable to be clearly detected. Parts of patients in groupⅢcan only be detected by diffuse intrarenal distribution of blood flow signals sparse.4 Using color Doppler energy (CDE) imaging to observe low-velocity blood flow signal, and grading. The distribution of renal blood flow was incomplete identical between diabetic patients in each group and normal adults (p<0.05). The CDE grade of renal artery flow signals didn't have significantly difference between the patients in diabetes with normal proteinuria and normal adults(p>0.05). The CDE grade of renal artery flow signals of patients with early DN stages and patients in DN with clinical proteinuria had statistical difference from normal adult's(p<0.05).5 Intrarenal blood flow in each group from the main renal artery (MRA) to segmental renal arteries (SRA), to interlobular renal artery (IRA), to arch renal artery (ARA), all of their peak systolic velocity (Vsmax), the lowest end-diastolic velocity (Vdmin), resistance index (RI) were progressively reduced. The Vsmax, Vdmin, RI of diabetes with normal albuminuria stage were no significant difference from normal adults (p>0.05). Vdmin of renal artery flow at each level of patients in early DN were lower than normal adults', Vsmax of ARA blood flow was lower than normal adults', and RI increased, the differences above were statistically significant (p<0.05). Vdmin of renal artery at all levels of patients with clinical proteinuria DN stage were lower than normal adults', Vsmax of ARA and IRA were lower than normal adults', RI of renal artery at all levels increased compared with normal adults', the results above were statistically significant ( p<0.05). RI of renal artery at all levels were related to 24-hour urinary albumin excretion rate, and the more peripheral circulation of the kidney near the renal arteries, the RI correlation with UAER more significant.6 The pathological stages of diabetic patients with each group were different in the distribution (p<0.05), patients in each group had the different pathological features. The renal artery RI at all levels was related to renal pathology, and the more peripheral circulation of the kidney near the renal arteries,the RI and pathological correlation more possible.Conclusions:1 It has great clinical value that ultrasonography as routine examination of diabetic nephropathy patients to study the occurrence, development and treatment of diabetic nephropathy.2 The renal blood perfusion and pulse Doppler blood flow parameters of patients with diabetic nephropathy have changed, of which peripheral artery blood flow parameters changed significantly,and the clinical significance of blood flow resistance index is more explicit.3 Intrarenal blood flow parameters can be sensitive to the reaction of the situation of the diabetic nephropathy patients'renal pathological changes.4 Diabetic nephropathy patients'renal artery resistance index and 24-hour urinary albumin excretion rate, renal histological grade were positively related, and the finer artery branches are, the better the relevance is.