Background and Aims: The Doppler resistive index was advanced as a useful parameter for quantifying the alterations in renal blood flow that may occur with renal diseases. The presence of splenomegaly is very significant in the diagnosis of several groups of diseases: immunological, inflammatory, reticuloendothelial proliferations, storage diseases and portal hypertension. This prospective study is designed to investigate whether there is an effect of splenomegaly on renal resistive index value of extrinsically compressed left kidney by using renal Doppler US.Methods: A total of 48 patients (22 male and 26 female) with splenomegaly (>130 mm) were evaluated by renal Doppler US examination. The etiologies and durations of splenomegaly were found to be different. Renal sphericity indices were calculated for demonstration of extrinsic compression (long axis/short axis). The resistive index values obtained via both compressed left kidney by splenomegaly and contralateral right kidney were measured. Mean values were calculated and difference of mean resistive index between both kidneys were compared.Results: The sphericity indices were higher in compressed left kidney (mean+/-SD) (2.4+/-0.4) than contralateral normal side (2.3+/-0.3). The mean RI of the compressed and contralateral kidney were 0.67 +/-0.5 and 0.65+/-0.4, respectively. The mean RI value of the left side is statistically higher than right side (p<0.01).Conclusions: During renal Doppler examinations it should be kept in mind that the extrinsic pressure caused by enlarged spleen may significantly alter renal RI measurements.

Introduction: Our aim was to study the changes in resistive index (RI) of the ipsilateral and contralateral kidneys following electromagnetic extracorporeal shock wave lithotripsy (SWL) of the kidney calculi.Materials and Methods: Using color Doppler ultrasonography, the RI was determined in 21 patients with unilateral caliceal and pelvic kidney calculi. The RI of the interlobar renal arteries were measured for the regions near and far from the calculi (distance, less and more than 2 cm), before, 30 minutes after, and 1 week after SWL. The same measurements were carried out for the contralateral kidney. Changes in the RI values and their relation with age were evaluated. Results: The RI near the calculi increased 30 minutes after SWL from 0.594±0.062 to 0.620±0.048 (P = .003; 95% confidence interval, 0.020 to 0.073), but returned to the pre-SWL values 1 week later. The RI values of the region remote from the calculus and in the contralateral kidney did not change significantly. There was a weak correlation between age and the RI far from the calculus before and 1 week after SWL. There were no relationships between the RI and age, sex, weight, blood pressure, and smoking.Conclusion: The results suggest that SWL of the kidney calculi changes the RI only near the calculus which is immediate, transient, and not age-related.  

Background: The renal resistive index (RI), measured using doppler ultrasound, reflects intrarenal vascular resistance. We evaluated the relationship between RI with nephropathy in patients with diabetic mellitus.Methods: This study was done in Al-Zahra hospital in Isfahan. Fifty seven patients with diabetes mellitus in 3 groups (stage I, II and III of nephropathy) were compared with 19 patients in control group. The patients with renal artery stenosis or severe renal failure were excluded from the study.Finding: The mean age was 56.42±10.45 years in patients. RI was 59.8±2.2 percent in patients in stage I of nephropathy and in stage II and III of nephropathy it was 61.4±5.8 and 82.4±11.1 percent respectively. RI in control group was 63.1±5.6 percent. The RI in diabetic patients in stage III was significantly higher than other groups (P<0.001).Conclusion: The results suggest that increased RI of the renal arteries can be more useful in patients in stage III of diabetic nephropathy.

Background/Objective: Doppler ultrasonography can be an effective method to assess the severity of diabetic nephropathy. This study was conducted to investigate the relationship between Doppler ultrasound resistive index (RI) values and the clinical and laboratory findings in patients with diabetic nephropathy.Patients and Methods: Doppler ultrasound was performed for 45 patients with type II diabetes mellitus and 30 healthy controls. Clinical and laboratory findings of cases and controls were also recorded.Results: Diabetic patients were categorized into 3 groups according to the severity of their nephropathy, based on the serum creatinine level and 24-hour urine protein. The mean±SD RI was 0.59±0.03 for the control group, 0.67±0.04 for stage I, 0.73±0.02 for stage II, and 0.85±0.07 for stage III diabetic nephropathy (p<0.001). RI was significantly associated with the 24-hour urine protein and creatinine (R2=0.75 and =0.67, respectively; p<0.001) and a suitable regression model was adopted to predict the 24- hour urine protein and serum creatinine level based on RI.Discussion: RI increases with the progression of diabetic nephropathy. RI can be used for estimation of the 24-hour urine protein and serum creatinine and for determining the stage of nephropathy, especially for patients not cooperating for collection of the 24- hour urine protein.

Background/Objective: The purpose of this study was to determine whether spectral Doppler ultrasound (US) parameters, including resistive index (RI) and publicity index (PI), or vascular pattern can be used to distinguish malignant from benign thyroid nodules. Patients and Methods: We prospectively examined 58 thyroid nodules in patients with solitary thyroid nodule undergoing surgery. Pathologic correlation was available for all nodules (30 malignant and 28 benign lesions). The flow pattern seen via power Doppler examination was ranked for each nodule on a scale of 0 to 4, in increasing flow order. Vascularity as determined by power Doppler US imaging was defined as absent, per nodular alone, mix per nodular and intranodular.For each nodule, the RI and PI values were recorded as the average of the recordings obtained. Surgical pathological examination results were used as a proof of final diagnosis to categorize all nodules as benign or malignant. Results: The malignant nodules had a mean RI of 0.76 ±0.13. These values were significantly higher than those associated with benign nodules (0.62±0.08) (P= 0.004). Malignant nodules had a mean PI of 1.26 ±0.40 that were also significantly different from those associated with benign nodules (0.96±0.19) (P=0.009). There was a significant correlation between grade 4 flow pattern (Intraocular) of the nodule and malignancy (P=0.006). Conclusion: The results of this study indicate that Doppler US characteristics including vascular pattern, RI and PI are useful parameters for distinguishing malignant from benign thyroid nodules and these indices, can be used as an adjuvant diagnostic method especially for follicular carcinoma where FNAB has some limitations.

Background and Aim: This study aimed to investigate the strength of the relationship between renal resistive index with left ventricular mass index, microalbuminuria, and retinopathy to find a predictive value of the renal resistive index in early detection of end-organ damage. Methods: Pediatric patients diagnosed with hypertension were included in this study between January 2020 and January 2022. Results: A total of 41 consecutive patients who were never treated for essential hypertension were included in this study. Microalbuminuria was detected in 10 patients (24%). Retinopathy was detected in only 2 patients (4. 9%). Echocardiographic data were available in 25 patients. The mean left ventricular mass index was 30±, 10 (17-53 g/m2. 7). Three male patients (12%) had left ventricular hypertrophy but none of the females had left ventricular hypertrophy. We categorized the patients into two groups according to the presence of microalbuminuria and compared the two groups. The value of the renal resistive index in the microalbuminuric group was significantly higher than in the nonalbuminuric group (0. 8±, 0. 2 vs. 0. 6±, 0. 2, P=0. 047). We found a positive correlation between renal resistive index and urine microalbumin (r=0. 636, P=0. 014). In regression analysis, higher resistive index values were independently associated with microalbuminuria but not left ventricular hypertrophy. (OR=-0. 633, 95% CI 24. 4-187. 2, P=0. 015) Conclusion: To our knowledge, this is the first study to analyze the correlation of RI with microalbuminuria in hypertensive children. We found a significantly higher resistive index in patients with microalbuminuria,we also found a correlation between these variables. This shows that this finding and an abnormal resistive index can be used as early signs of hypertension.