Use of sonography and radioisotope renography to diagnose hydronephrosis in patients with spinal cord injury

OBJECTIVE: To study the accuracy of sonography and radioisotope renography in detecting hydronephrosis in patients with spinal cord injury (SCI). DESIGN: Prospective, blinded comparison study. SETTING: Rehabilitation hospital affiliated with a medical college. PARTICIPANTS: One hundred and nine patients with SCI (21 women, 88 men) participated. INTERVENTIONS: Comprehensive urologic examinations including clinical evaluation, laboratory tests, intravenous urography (IVU), sonography, radioisotope renography (renal scan), voiding cystourethrography, and cystometry. The findings at sonography and renal scan were separately compared with the final diagnosis interpreted by IVU and clinical findings. MAIN OUTCOME MEASURES: Effective renal plasma flow, pyelocaliectasis, and positive and negative predictive value. RESULTS: A total of 235 kidneys were analyzed. Sonography correctly excluded the presence of hydronephrosis in 173 of 192 nonobstructed kidneys. Sonograms were interpreted as positive in 41 of 43 kidneys with documented hydronephrosis. Renal scan correctly excluded 161 nonobstructed kidneys. The renal scan detected 39 of 43 kidneys with hydronephrosis. The sensitivity of sonography was.96 with a specificity of.90. Renal scan reached a sensitivity of.91 with a specificity of.84. CONCLUSION: Sonography and renal scan are safe, sensitive, and specific for detecting hydronephrosis. Combined use of both methods appears to be a reliable alternative to IVU in the long-term follow-up for patients with SCI with neurogenic bladder dysfunction.     

The influence of hydration and bladder distension on the sonographic diagnosis of hydronephrosis.

Renal sonography is frequently employed to exclude obstructive uropathy in patients with uremia. Sonographic findings of moderate bilateral hydronephrosis were encountered in a dehydrated patient undergoing rehydration. Subsequent excretory urography and a follow-up renal sonogram were normal. To investigate the possibility that hydration and bladder distension in an otherwise normal and unobstructed collecting system could result in hydronephrosis detectable by ultrasound, 23 apparently normal volunteers underwent renal sonography in the hydrated and basal states. The filled urinary bladder in a patient undergoing hydration frequently results in the sonographic appearance of hydronephrosis.     

Accuracy of sonography with a hydration test in differentiating between excretory renal obstruction and renal sinus cysts

PURPOSE: The aim of this prospective study was to determine whether sonography with a hydration test to induce diuresis can be used to reliably differentiate between excretory renal obstruction and renal sinus cysts. METHODS: We performed sonographic examination of all patients diagnosed with minimal or moderate obstruction of the intrarenal collecting system or renal sinus cysts on the basis of excretory urography, CT, or both between September 1, 1998, and October 31, 1999. The largest fluid-filled structures in the renal sinus were sonographically measured before and after each patient ingested 1.5 l of water. Cases in which the maximum diameters of the largest anechoic structures increased by at least 10% after hydration were diagnosed with excretory renal obstruction. The sonographic diagnoses were compared with the final diagnoses on excretory urography, CT, or both. RESULTS: Both kidneys were affected in 16 of the 36 patients examined, for a total of 52 kidneys. The sonographic diagnosis was consistent with the results of urography or CT in 48 (92%) of the 52 kidneys. The sonographic approach had a specificity of 92% and a sensitivity of 93% for the diagnosis of excretory renal obstruction, with only 1 false-negative and 3 false-positive results. CONCLUSIONS: When used with the stimulated diuresis test, sonography can reliably distinguish between excretory renal obstruction and renal sinus cysts and can be used as an alternative to other imaging techniques such as urography.     

Renal sonography in the diagnosis of renal obstruction or hydronephrosis in patients with cervical cancer

PURPOSE: The aim of this prospective study was to evaluate the role of renal sonography and its use as an alternative to intravenous urography in detecting ureteral obstruction or hydronephrosis in patients with cervical cancer. MATERIALS AND METHODS: Patients with biopsy-confirmed carcinoma of the cervix who were referred to the radiotherapy center from February 6, 2001, through July 20, 2001, were enrolled in this trial. All patients had previously undergone clinical staging by physical examination and either intravenous urography or CT scanning as the standard tests for diagnosing ureteral obstruction or hydronephrosis. All patients underwent renal sonography as an alternative diagnostic tool for diagnosing ureteral obstruction or hydronephrosis. RESULTS: Forty patients were enrolled. Their mean age was 46 years (range, 26-65 years). According to the FIGO staging system, 12% of the patients had clinical stages 1B2 and 2A disease, 20% had stage 2B, 8% had stage 3A, 50% had stage 3B, and 10% had a postoperative recurrence of cervical cancer. Thirty-four patients had had intravenous urography and 6 had had CT scans of the abdomen and pelvis. Sensitivity, specificity, positive and negative predictive values and overall accuracy rates for renal sonography were 76.5% (13/17), 100% (23/23), 100% (13/13), 85% (23/27), and 90% (36/40), respectively. Seventy-five percent (3/4) of the false-negative results occurred in patients with pelvic sidewall thickening on physical examination. CONCLUSIONS: Renal sonography may be used as an effective and relatively low-cost means of diagnosing ureteral obstruction in patients with cervical cancer without clinically evident pelvic sidewall thickening.     

Application of renal Doppler sonography in the diagnosis of obstructive uropathy in patients with spinal cord injury

OBJECTIVES: To assess renal resistive index (RI) changes in patients with spinal cord injury (SCI) who have obstructive uropathy and to determine if an RI of 0.7 or more is useful in identifying such patients. DESIGN: Prospective cross-sectional study. SETTING: Rehabilitation hospital affiliated with a medical university. PARTICIPANTS: A convenience sample of 99 kidneys of 51 SCI patients (38 men, 13 women; mean age, 38.8+/-14.0 y) with neuropathic bladder dysfunction. INTERVENTIONS: Ultrasonic examination to assess the degree of hydronephrosis, Doppler sonography to calculate renal vascular RIs, and radioisotopic renography to assess renal function and to determine excretory curves. Kidneys were assigned to control or obstructive uropathy groups, and RIs were compared for statistical significance (Student t test) and to assess whether an RI of 0.7 is a distinguishing criterion. MAIN OUTCOME MEASURES: RI and sensitivity. RESULTS: Average RIs were .58+/-.07 in the control group (71 kidneys) and .65+/-.08 in the uropathy group (28 kidneys) (P<.001). The sensitivity of using an RI of 0.7 or more to identify patients with obstructive uropathy was 39%. The c statistic of the receiver operating characteristic curve was .72. CONCLUSIONS: RIs increased in SCI patients with obstructive uropathy. In patients with SCI, urinary findings fit the chronic partial obstruction pattern. A renal RI of 0.7 or more was a poor indicator of obstructive uropathy in such patients.     

The role of ultrasonics in the diagnosis of kidney diseases

A retrospective comparative assessment of the diagnostic value of excretory urography (EU), scintigraphy (SCG) and ultrasonography (USG) of the kidneys was conducted in 100 patients. The diagnosis in 26 patients was confirmed by CT, angiography, at operation or autopsy. Chronic pyelonephritis was diagnosed in 54% of the patients, renal changes in essential hypertension--9%, hydronephrosis in 8%, abnormal shape and position of the kidneys in 8%, malignant tumors in 7%, chronic glomerulonephritis in 8%, renal cysts in 2%, multicystosis in 1%, kidney contusion in 1%, paranephritis in 1%, and apostematous nephritis in 1%. The sensitivity of EU was 71%, that of SCG 52%, that of USG 93%. The specificity of EU was 66%, SCG--8%, that of USG 90%.     

超声造影评估脊髓损伤并发肾积水患者肾功能的价值

目的 探讨超声造影评价脊髓损伤并发肾积水患者肾功能的临床价值。方法 2015年10月至2018年11月,选择脊髓损伤并发肾积水并且肾功能下降患者23例(脊髓损伤组)和健康志愿者19例(对照组),双肾进行超声造影检查并与肾动态显像结果进行对照分析。利用软件分析采集的超声造影图像,在肾皮质选取感兴趣区(ROI),绘制时间强度曲线。以达峰时间(TTP)、峰值强度(DPI)、上升支斜率(A)和曲线下面积(AUC)为自变量,肾动态显像结果为因变量做Logistics回归,再进行ROC曲线分析。结果 两组血肌酐和尿素比较均无显著性差异(P> 0.05)。脊髓损伤组TTP显著长于对照组(t = 5.068, P < 0.001),A和AUC明显低于对照组( t > 3.784, P < 0.01)。AUC是肾功能损伤的影响因素( P <0.01)。AUC越小,肾损伤的可能性越大,敏感性和特异性之和最大为1.759,对应的AUC为982.518 dBs。结论 超声造影可以评价脊髓损伤并发肾积水患者肾功能。时间强度曲线AUC减小,提示肾功能受损。     

The sensitivity and specificity of the digital rectal examination for detecting spinal cord injury in adult patients with blunt trauma

STUDY OBJECTIVES: The digital rectal examination (DRE) may assist physicians in detecting spinal cord injury in patients with blunt trauma. However, the test characteristics of the DRE for detecting spinal cord injury are unknown. METHODS: We conducted a retrospective review of consecutive adult patients with blunt trauma over a 2-year period. The DRE result was compared with the presence or absence of spinal cord injury at discharge. RESULTS: A total of 1032 adult patients with blunt trauma had a DRE. Of these, 54 (5.2%) had diagnoses consistent with spinal cord injury. Ninety-nine patients had decreased rectal tone, 27 of whom also had spinal cord injuries. The sensitivity, specificity, positive predictive value, and negative predictive values were 50%, 93%, 27%, and 97%, respectively. CONCLUSION: The DRE is insensitive to spinal cord injury and has a poor positive predictive value. The high specificity must be balanced against the large number of false-positive results.     

Emergency Ultrasound and Urinalysis in the Evaluation of Flank Pain

Objectives: To determine the sensitivity and specificity of limited emergency ultrasonography of the kidney in diagnosing renal colic. Methods: This was a prospective observational trial from December 2001 to December 2003 at a suburban emergency department. Patients who presented with flank pain suspicious for renal colic were enrolled. Exclusion criteria included fever, trauma, known current kidney stone, unstable vital signs, and inability to provide consent. All patients underwent sequential emergency ultrasonography and computed tomography of the kidneys and bladder. Data were analyzed using chi-square analysis. The primary outcome was the sensitivity and specificity of ultrasonography. Results were also stratified for presence of hematuria. Results: Fifty-eight of the 104 patients enrolled in the study were diagnosed with renal colic. The overall sensitivity and specificity of bedside ultrasonography for the detection of hydronephrosis were 86.8 (95% confidence interval [CI] = 78.8 to 92.3) and 82.4 (95% CI = 74.1 to 88.1), respectively. In patients with hematuria, hydronephrosis by emergency ultrasonography demonstrated a sensitivity and specificity of 87.8 (95% CI = 80.3 to 92.5) and 84.8 (95% CI = 73.7 to 91.9), respectively. In 55 of the cases, the initial computed tomograph was read by a resident and later re-read by an attending physician. Using the reading of the attending physician as the criterion standard resulted in a sensitivity and specificity of 83.3 (95% CI = 73.2 to 88.0) and 92.0 (95% CI = 79.9 to 97.6), respectively. Conclusions: Emergency ultrasonography of the kidneys shows very good sensitivity and specificity for diagnosing renal colic in patients with flank pain and hematuria.     

Utility of the resistance index ratio in differentiating obstructive from nonobstructive hydronephrosis in children.

PURPOSE: We assessed the utility of the resistance index ratio (RIR) in distinguishing between obstructive and nonobstructive upper urinary tract dilatation in children. METHODS: Twenty-three children (7 days-14 years old) with unilateral dilated collecting systems and a contralateral normal kidney were prospectively evaluated by duplex Doppler sonography. We measured the resistance index (RI) of the intrarenal arteries and calculated the RIR. Ninety-six normal kidneys in 48 controls were also evaluated. RESULTS: Twelve kidneys were proved to be obstructed at the ureteropelvic junction, and 11 were found by renal scintigraphy with furosemide and/or by surgery to have nonobstructive dilatation. The mean RIR differed significantly between the obstructed and dilated nonobstructed kidneys (1.16+/-0.04 versus 1.04+/-0.04, respectively; p < 0.01). After surgical correction of ureteropelvic junction obstruction, the obstructed kidneys showed significant drops in the RIR (1.18+/-0.03 to 1.07+/-0.03, p < 0.01). The RIR showed no statistically significant relationship with age (r = -0.268, p > 0.01); however, the RI declined with increasing age (r= -0.414, p < 0.01). An RIR cut-off value of > or = 1.10 provided a good discriminatory level, resulting in a sensitivity of 92%, a specificity of 97%, a positive predictive value of 85%, and a negative predictive value of 97%. CONCLUSIONS: An RIR cut-off value of > or = 1.10 appears to be an effective parameter for evaluation and follow-up of unilateral obstructive hydronephrosis in children.     

Sonography: a useful tool to detect the mechanical causes of renal transplant dysfunction.

PURPOSE: The purpose of this study was to evaluate the utility of sonography in distinguishing between mechanical and nonmechanical causes for renal transplant dysfunction. METHODS: We reviewed all ultrasound examination reports (n = 286) for 63 consecutive patients who received 64 renal transplants. We assessed the sensitivity and specificity of different degrees of hydronephrosis (mild, moderate, or severe) in detecting urinary tract obstruction; different volumes of new or increasing peritransplant fluid in detecting urine leaks; different total volumes of peritransplant fluid in predicting significant compression of the transplant; and Doppler vascular criteria for predicting arterial and venous occlusion. RESULTS: All mechanical complications were detected (100% sensitivity) with specificities of 91.9% for ureteral obstruction (criterion, moderate hydronephrosis), 83.4% for urine leaks (criterion, any new fluid or any increase), 91.4% for fluid collections that compressed the transplant (criterion, > 100 ml), and 100% for vascular occlusion (criteria, no flow for arterial occlusion; no venous flow and reversal of arterial flow during diastole for venous occlusion). CONCLUSIONS: Sonography is very useful in distinguishing between mechanical and nonmechanical causes for renal transplant dysfunction. It has high sensitivity and acceptable specificity in this setting.     

Renal function in spinal cord injury: a preliminary report

To investigate the effect of current bladder management techniques on renal function in spinal cord injury (SCI), we followed 99 patients by frequent examinations, excretory urograms, and iothalamate short renal clearances. Fifty-eight percent of the subjects emptied their bladders by catheter-free methods (bladder retrained), 32% by intermittent self-catheterization, and 10% by indwelling urethral catheters. All remained clinically well, but more and earlier excretory urogram abnormalities occurred in the intermittent self-catheterization group. Twenty-one percent of the intermittent self-catheterization group but only 5% of the bladder retrained group had excretory urogram abnormalities. Declines of more than 10% in short renal clearance values were noted in 30% of intermittent self-catheterization patients and in 15% of bladder retrained patients. Our preliminary data support the need for close surveillance and follow-up after SCI rehabilitation, even in patients appearing clinically well. These data also suggest that renal function can be preserved with current bladder management methods, with bladder retraining having a slight edge over intermittent self-catheterization.     

Ultrasonography by emergency physicians in patients with suspected ureteral colic

We performed a prospective study of patients with suspected ureteral colic to evaluate the test characteristics of bedside renal ultrasonography (US) performed by emergency physicians (EPs) for detecting hydronephrosis, and to evaluate how US can be used to predict the likelihood of nephrolithiasis. Thirteen EPs performed US, recorded the presence of hydronephrosis, and made an assessment of the likelihood of nephrolithiasis. All patients underwent i.v. pyelography (IVP) or unenhanced helical computed tomography (CT). There were 126 patients in the study: 84 underwent IVP; 42 underwent helical CT. Test characteristics of bedside US for detecting hydronephrosis were: sensitivity 72%, specificity 73%, positive predictive value (PPV) 85%, negative predictive value (NPV) 54%, accuracy 72%. The PPV and NPV for the ability of the EP to predict nephrolithiasis after performing US were 86% and 75%, respectively. We conclude that bedside US performed by EPs may be used to detect hydronephrosis and help predict the presence of nephrolithiasis.     

The renal resistive index as a predictor of acute hydronephrosis in patients with renal colic

IntroductionThe objective of this study was to determine whether the renal resistive index (RI) can predict hydronephrosis in patients with renal colic (RC) and whether or not its performance is time-dependent.Materials and methodsThe study population was composed of 54 patients admitted for unilateral RC. At the time of the first observation (time point I, tpI), each patient underwent routine examinations, abdominal ultrasonography, and renal color Doppler ultrasound (CDUS) with measurement of the RI. The two imaging studies were repeated 6, 12, 18, 24, 36, and 48 h later (tpII, tpIII, tpIV, tpV, tpVI, tpVII). In addition, each patient underwent non-contrast urinary tract CT 48–60 h after admission. A mean renal RI of >0.70 (mRI+) for the symptomatic kidney was considered indicative of obstruction. Patients were retrospectively divided into two groups: those who developed dilatation (group A) and those who did not (group B).ResultsA mRI+ on CDUS predicted the onset of hydronephrosis with 100% sensitivity, 84% specificity, 92.6% accuracy, PPV and NPV of 87.9% and 100%, and diagnostic efficiency of 84%. In group A, mRI+ were always observed before onset of hydronephrosis in a time-dependent manner. In group B, mRI+ were observed occasionally in 4/25 patients (16%) and all were recorded at tpII. In these cases, the RI had returned to normal by tpIII.ConclusionsIn our RC patients, renal RI obtained with CDUS predicted the onset of acute dilatation with higher sensitivity, specificity, accuracy, and diagnostic efficiency than ultrasonography, and it can be used routinely in the emergency department to supplement ultrasound findings.     

Ultrasonography by emergency physicians in patients with suspected ureteral colic

We performed a prospective study of patients with suspected ureteral colic to evaluate the test characteristics of bedside renal ultrasonography (US) performed by emergency physicians (EPs) for detecting hydronephrosis, and to evaluate how US can be used to predict the likelihood of nephrolithiasis. Thirteen EPs performed US, recorded the presence of hydronephrosis, and made an assessment of the likelihood of nephrolithiasis. All patients underwent i.v. pyelography (IVP) or unenhanced helical computed tomography (CT). There were 126 patients in the study: 84 underwent IVP; 42 underwent helical CT. Test characteristics of bedside US for detecting hydronephrosis were: sensitivity 72%, specificity 73%, positive predictive value (PPV) 85%, negative predictive value (NPV) 54%, accuracy 72%. The PPV and NPV for the ability of the EP to predict nephrolithiasis after performing US were 86% and 75%, respectively. We conclude that bedside US performed by EPs may be used to detect hydronephrosis and help predict the presence of nephrolithiasis.     

超声造影评价脊髓损伤并发肾积水患者肾血流灌注的可行性

目的探讨超声造影评价脊髓损伤（SCI）并发肾积水患者肾血流灌注的可行性。 方法选取2015年10月至2017年1月中国康复研究中心收治的SCI并发肾积水导致慢性肾病患者16例（SCI组）和本院体检中心健康志愿者9例（对照组）,双肾进行常规超声检查后进行超声造影检查。观察造影后肾脏血流灌注情况并采集图像,在肾皮质选取感兴趣区域（ROI）,绘制时间强度曲线。两组时间-强度曲线四个参数达峰时间（TTP）、峰值强度（DPI）、上升支斜率（A）、曲线下面积（AUC）进行秩和检验。 结果SCI组较对照组TTP延迟,RTTP 11.94（9.90~18.87）、LTTP 22.61（11.84~28.20）,DPI降低,RDPI 10.08（9.34~11.04）、LDPI 9.17（8.86~11.88）,A减少,RA 0.92（0.66~1.13）、LA 0.47（0.35~1.03）,AUC减少,RAUC 836.01（676.03~1050.95）,LAUC 906.56（722.11~1043.17）,差异均有统计学意义（Z=-3.114、-2.860、-3.001、-2.661、-3.608、-3.011、-2.415,P均<0.05）。 结论超声造影可以评价SCI并发肾积水患者肾血流灌注,SCI患者TTP延迟,A降低,AUC减少。     

Doppler sonography in the diagnosis of urinary tract obstruction by stone

PURPOSE: This study was conducted to evaluate the accuracy of Doppler sonography in renal colic due to obstruction and to assess whether the resistance index (RI) and interrenal RI difference (DeltaRI) are time-dependent parameters. SUBJECTS AND METHODS: Obstructed and unobstructed contralateral kidneys in 28 patients with renal colic and normal kidneys in 27 control subjects were prospectively evaluated with Doppler sonography. Mean RI, mean DeltaRI, and duration of pain were evaluated. Statistical analysis was done using paired and independent t-tests. RESULTS: Mean RIs of the control-group, obstructed, and contralateral kidneys were 0.60, 0.71, and 0.61, respectively; mean DeltaRI values of the obstructed and control-group kidneys were 0.10 and 0.03, respectively. Differences in mean RI between obstructed and contralateral or control-group kidneys were statistically significant (p < 0.001). There was a statistically significant difference in DeltaRI between patients and controls (p < 0.001). The difference between the RI values of kidneys with low-grade (0.70) and high-grade obstructions (0.72) was not statistically significant. The difference between the DeltaRI values of kidneys with low-grade (0.08) and high-grade obstructions (0.13) was statistically significant (p < 0.05). Differences in the mean RI and mean DeltaRI values between 3 groups of patients categorized according to the duration of pain were not statistically significant. CONCLUSIONS: Along with gray-scale sonography and intravenous urography, Doppler sonography can be used in the evaluation of renal obstruction. RI and DeltaRI are not time-dependent parameters.     

流入敏感翻转恢复序列MR血管造影诊断肾动脉狭窄

目的前瞻性评价非对比增强流入敏感翻转恢复(IFIR)序列MRA(IFIR-MRA)对肾动脉狭窄的诊断价值。方法对60例可疑肾血管性高血压患者行肾动脉IFIR-MRA和增强CTA检查,比较两种方法的图像质量、肾动脉显影效果和肾动脉狭窄分级。以Spearman相关系数评价两种方法所得结果的相关性。以CTA为参照,计算IFIR-MRA诊断肾动脉狭窄的敏感度、特异度、阳性预测值(PPV)、阴性预测值(NPV)和准确率。结果 CTA和IFIR-MRA均显示126支主肾动脉。IFIR-MRA图像质量、肾动脉分级及肾动脉狭窄诊断与CTA结果的Spearman相关系数分别为0.773、0.998和0.833(P均<0.001)。IFIR-MRA诊断肾动脉狭窄的敏感度、特异度、PPV、NPV和准确率分别为100%(23/23)、98.06%(101/103)、92.00%(23/25)、100%(101/101)和98.41%(124/126)。结论以CTA为参照,非对比增强IF-IR-MRA可良好显示肾动脉,诊断肾动脉狭窄具有很高的敏感度、特异度和准确率,可作为可疑肾动脉狭窄患者的首选检查方法。     

小儿肾积水血流动力学观察及临床意义

目的:研究小儿肾积水血流动力学指标及其临床意义。方法:应用彩色多普勒超声对20例正常小儿肾脏及30例小儿积水肾进行血流动力学研究。结果:①正常小儿肾脏主肾动脉(MRA)、段动脉(SRA)、叶间动脉(IRA)的血流收缩期峰值速度(PS)、舒张期峰值速度(ED)、平均速度(TAMx)、最低速度(TAMn)依次逐渐减小(P<0.01),MRA、SRA、IRA的阻力指数(RI)无明显改变(P>0.05);积水肾的PS、ED、TAMx、TAMn比正常肾脏的血流速度低(P<0.01),积水肾RI比正常肾RI大(P<0.05)。②肾积水术后1个月RI改善最明显,以后的改善将减缓,而其余各项指标在1~6个月期间恢复最为明显。结论:①肾积水时其血流动力学发生相应的变化,其中RI的变化具有较大临床意义。②梗阻性小儿肾积水,其SRA段RI>0.66。③术后RI值不降或反而升高,提示梗阻未完全解除,需再次手术治疗。