Ultrasonic assessment of renal transitional cell carcinoma: preliminary report.

The value of ultrasound in determining the etiology of nonopaque filling defects seen in the renal pelvis at intravenous urography is under study. The ultrasound findings in three patients with proven transitional cell carcinoma of the kidney were similar and consisted of separation of the central renal echo complex by a region of low-intensity echoes. This pattern is distinct from characteristically echogenic nonopaque renal calculi and anechoic hydronephrosis. Renal collecting system blood clots may have an echo pattern similar to collecting system tumors, but can usually be distinguished by their mobility and transitory nature. Further investigation into the specificity and sensitivity of the ultrasonic diagnosis of renal collecting system masses is underway.     

The sonographic appearance of acute focal pyelonephritis 8 years experience

AIM: Acute focal pyelonephritis (AFP) is a variant of pyelonephritis in which single or multiple discrete areas show changes of inflammation. The reported sonographic appearances of AFP are varied but are typically described as being echopoor. The purpose of this study was to review the sonographic appearances of AFP and attempt to explain the range of findings by correlation with clinical details. MATERIALS AND METHODS: We reviewed retrospectively the sonographic findings and medical records of 17 cases of AFP. The study group consisted of 13 women and four men (mean age 20 years). Lesions were designated as echogenic, echopoor or of mixed echogenicity as compared to the adjacent renal cortex, and to the liver or spleen. RESULTS: The abnormal areas were echogenic in 12 patients, echopoor in three and of mixed echogenicity in two. An attempt was made to explain the variation in appearances by correlation with clinical details including the patient's age, the duration of symptoms, the length of antibiotic treatment and the presence of haematuria. CONCLUSION: Areas of acute focal pyelonephritis may be echogenic, echopoor or of mixed echogenicity. Our data would suggest that areas of increased echogenicity are more common. There is no discernible correlation with clinical findings.     

Hemorrhagic focal bacterial nephritis: findings on gray-scale sonography and CT

Five patients with acute focal bacterial nephritis and hematuria had sonographic and CT findings atypical for renal infection. Sonographically, each presented with an echogenic focus in the renal parenchyma. Noncontrast CT images showed an area of increased density in the corresponding segment of the kidney in three patients, mixed high and low density in one patient, and low density alone in the remaining patient. It is proposed that these appearances result from the presence of hemorrhage at different stages, associated with focal infection. Venous compromise is suggested as the etiology.     

Renal dysplasia: sonographic findings

In 38 pediatric patients (predominantly neonates) with a proved pathologic diagnosis of renal dysplasia, a variety of sonographic appearances were seen. When the obstruction was at the level of the ureteropelvic junction (12 patients, 12 kidneys), the typical appearance was of a large kidney containing multiple large or moderate-sized cysts. When the obstruction was at the level of the distal ureter (14 patients, 14 kidneys), a smaller kidney containing a few cysts of variable sizes was usually seen. When the obstruction was at the level of the urethra (eight patients, 13 kidneys), the kidney was typically small with few or no cysts. In four patients (seven kidneys) in whom no cause of the obstruction was evident, the kidneys were small and echogenic. There was one case of segmental dysplasia.     

B-mode ultrasound and the nonvisualizing kidney in pediatrics.

Ultrasonic definition of the kidney is independent of renal function and therefore capable of imaging impaired or dysplastic renal tissue, In 28 cases, B-mode scanning delineated one or both kidneys which failed to visualize during intravenous pyelography. Similar imaging of both kidneys was obtained in 10 cases of renal failure in which intravenous pyelography was not attempted. The presence and relative severity of hydronephrosis was established. In three cases of multicystic kidney, a diagnostic appearance was elicited. In these instances, in one additional case of renal dysplasia, and in three cases of severe obstructive uropathy, sonography provided the only presurgical definition of the abnormal kidney. Suspected kidney enlargement was rapidly confirmed in a case of renal vein thrombosis and excluded in a case of chronic renal failure. In both instances hydronephrosis was excluded. In 12 of the 38 cases, ultrasonic guidance was utilized for percutaneous renal biopsy.     

Gray scale ultrasonic appearances of renal transplant rejection.

Ultrasonic examination of renal transplants with special attention to the parenchymal echo pattern has been undertaken in 43 patients. In the normal renal transplant, the pyramids, cortex and renal sinus can be distinguished. Renal transplant rejection is manifested by swelling and decreased echogenicity of the pyramids and hyperechogenic cortex. In addition, large anechoic areas due to hemorrhagic infarcts and necrosis are seen. In long-standing rejection, a normal or small-sized kidney with an irregular intrarenal echo pattern is observed. In 13 cases of acute tubular necrosis, none of the above appearances could be demonstrated. Serial ultrasonic scans are essential to reveal evolutionary changes of the rejection process.     

Ultrasonic detection of renal tumor extension into the inferior vena cava.

Five cases of extension of renal carcinoma into the inferior vena cava were detected using gray scale ultrasonography. Two different ultrasonographic appearances reflecting the intracaval tumor were observed. Four patients had one or two intraluminal echogenic nodules or thrombi, and the fifth case manifested generalized caval dilatation with innumerable diffuse low amplitude echoes emanating from the lumen. The role of ultrasonography in the complete evaluation of the patient with renal carcinoma is discussed, and the ultrasonographic features of intracaval tumor are demonstrated.     

Radiological anatomy of the kidney revisited

In recent years some structures or features such as the "inter-renuncular septum", the "echogenic triangle" and the "echogenic line" have been described to support the concept of a kidney resulting from the fusion of two masses or renunculi. To clarify this concept and to understand the meaning of the above echographic features better, the authors have examined prospectively by sonography the kidneys of 50 children, 200 adults with a single collecting system, 25 adults with a duplicated collecting system and 32 cadavers. Furthermore, to help explain the sonographic features, we have examined 32 cadaver kidneys with sonography and 10 cadaver kidneys with magnetic resonance imaging (MRI). The sonographic, MRI and anatomical correlations have shown that the "echogenic triangle" and the "echogenic line" are not renuncular residuals, but simply an extension of the hilar fat visible when the renal sinus is rather deep. The intermediate cortical mass is not a septum dividing the kidney into an upper and lower renunculus, but a column of parenchymal tissue crossing the renal sinus, which, from an anatomical point of view, is an accessory renal lobe. The presence of two renunculi, suggested in a previous study with cortical nephrotomography, has not been confirmed.     

Renal subcapsular rim sign. Radionuclide pattern

The renal cortical rim sign is a radiological term describing the thin peripheral nephrogram of 2-4 mm thick which is from the peri-renal capsular collateral circulation in an otherwise nonfunctioning kidney. Radionuclides are used frequently in the estimation of renal function. A neonate with renal vein thrombosis demonstrated a rim sign on renal scan with Technetium DTPA. The rim sign on renal scan can be differentiated from severe hydronephrosis or multicystic kidney both of which may have a peripheral thin cortex which functions late on the renal scan. The rim sign in renal vein thrombosis was best visualized during the early blood pool phase when there was a considerable amount of radioactivity in the blood pool.     

Coexisting renal vein thrombosis and bilateral adrenal hemorrhage: renoscintigraphic demonstration

A rare case of simultaneous renal vein thrombosis and bilateral adrenal hemorrhage is presented, showing the utility of Tc-99m DTPA and DMSA renal scans to identify the condition and to assess renal function. The characteristic appearances of suprarenal tracer-free areas encircled by peripheral radioactive rims over the inferiorly displaced kidneys on a Tc-99m DTPA renal scan, and that of the flattened upper poles of the kidneys on a Tc-99m DMSA scan, were pathognomonic and strongly indicative of bilateral adrenal hemorrhage. These two scans also showed markedly diminished tracer uptake in the poorly functioning right thrombosed kidney. Follow-up imaging using these two renal scans well demonstrated the functional and morphologic alterations and recovery of the kidneys.     

High-resolution real-time compound ultrasound imaging of transient protein-losing gastropathy of childhood

We report the case of a 1.5-year-old girl with transient protein-losing gastropathy with hypertrophic gastric folds (PLGH). The diagnosis of PLGH was made by abdominal ultrasound (US) and not by an upper gastrointestinal (UGI) study as reported in many previous publications. Real-time compound ultrasound imaging showed in high detail the echogenic thickening of the mucosal gastric layer and associated hyperaemia on colour Doppler US. These ultrasonic findings highly correlated with the endoscopic US findings and microscopic changes of the gastric wall in PLGH. An awareness of the high-resolution abdominal ultrasound appearances of PLGH may facilitate earlier diagnosis and obviate the need for an upper GI contrast series.     

Rescue of renal function after endovascular revascularization of acute aorto-renal bypass occlusion in a patient with solitary kidney: a case report

Renal artery occlusion represents an early diagnostic urgency to prevent kidney injury or, even more grave, kidney failure. However, diagnosis is often a challenge due to nonspecific and sporadic symptoms and signs, resulting in misdiagnosis, missed, or delayed diagnosis. The patient ought to be evaluated by a multidisciplinary team to select the best treatment.We describe a 62-year-old man''s case study. The patient had a left solitary kidney with an aortorenal artery bypass thrombosis. The renal function resumes 24 hours after the interventional radiology procedure. Based on our experience, revascularization of aortorenal artery bypass thrombosis may save renal function even after long ischemia times of over 24 hours.     

膜性肾病并发肾静脉血栓的彩色多普勒超声表现分析

目的探讨膜性肾病患者并发肾静脉血栓的彩色多普勒超声表现及其临床意义。方法膜性肾病27例,用二维超声和彩色多普勒超声观察肾脏的大小、形态、内部回声及肾静脉内是否有血栓。结果 27例中左肾主静脉血栓形成6例,段支1例,右肾主静脉血栓形成3例,段支1例,双肾主静脉血栓形成1例,本组27例膜性肾病患者并发肾静脉血栓的发生率为44%。结论彩色多普勒超声可作为诊断肾静脉血栓的首选方法。     

Bone scan findings in hypervitaminosis D: case report

Bone scans in three patients showed generalized symmetrical increased uptake of radiopharmaceutical by the skeleton and absent or faint kidney images. It is thought that these appearances may be attributable to excess vitamin D, but other possible contributing factors, including the presence of renal osteodystrophy, are discussed.     

High-resolution real-time compound ultrasound imaging of transient protein-losing gastropathy of childhood

We report the case of a 1.5-year-old girl with transient protein-losing gastropathy with hypertrophic gastric folds (PLGH). The diagnosis of PLGH was made by abdominal ultrasound (US) and not by an upper gastrointestinal (UGI) study as reported in many previous publications. Real-time compound ultrasound imaging showed in high detail the echogenic thickening of the mucosal gastric layer and associated hyperaemia on colour Doppler US. These ultrasonic findings highly correlated with the endoscopic US findings and microscopic changes of the gastric wall in PLGH. An awareness of the high-resolution abdominal ultrasound appearances of PLGH may facilitate earlier diagnosis and obviate the need for an upper GI contrast series.

     

The junctional parenchymal defect: a sonographic variant of renal anatomy

A triangular echogenic area in the upper pole renal parenchyma can be identified at times during routine sonography of the right kidney. Thirty such cases are presented. Occasionally similar echogenic defects in the parenchyma can be seen posteriorly in the lower pole and in the left kidney. These defects in the parenchyma result from normal extensions of the renal sinus of kidneys that have a distinct division of their upper and lower poles. This is due to partial fusion of two embryonic parenchymatous masses called renunculi. The defects in the parenchyma occur at the junction of the renunculi; hence we have termed them junctional parenchymal defects. In order to differentiate them from pathologic conditions, one must identify their characteristic location and demonstrate continuity with the renal sinus.     

The interrenicular junction: a mimic of renal scarring on normal pediatric sonograms

A triangular, echogenic focus of perirenal tissue in the anterosuperior or posteroinferior margin of the kidney, the junctional parenchymal defect (JPD), and an oblique echogenic line, the interrenicular septum (IRS), connecting the JPD to the renal hilum are normal sonographic findings in the pediatric age group. They are manifestations of an oblique interface between the two parts (reniculi) of one kidney. They should not be mistaken for renal scars. Prospectively, in a group of 100 children, either the JPD or IRS was seen in 46% of right kidneys and 19% of left kidneys. Retrospectively, the JPD was seen in 47% of right kidneys and 18% of left kidneys, and the IRS was seen in 39% of right kidneys and 12% of left kidneys.     

Renal vein thrombosis: an underdiagnosed complication of multiple renal abnormalities.

Thirty-one cases of renal vein thrombosis (RVT) were reviewed retrospectively for clinical laboratory, and radiographic findings. An underlying renal disorder was present in 28 cases, absent in only 3. This supports other evidence that RVT is usually a complication of renal disease rather than a primary event, and that nephrotic syndrome may be due to renal disease rather than RVT. The findings also confirmed the large spectrum of urographic appearances in RVT, and were used as a basis for developing specific and liberal indications for renal venography.     

The anatomic splenic flexure: an ultrasonic renal impostor.

The anatomic splenic flexure of the colon occupies the left renal fossa in patients with agensis or ectopic of the left kidney. On ultrasonic scans, the colon filled with stool or fluid may simulate a kidney or mass. This mass is often comma shaped on the transverse scans and lacks good definition of its inferior margin on longitudinal scans. An evaluation of a patient with only right renal function should combine radiologic techniques with ultrasonography to establish the correct diagnosis.     

Abnormal cortical appearances in pediatric renal allografts.

Renal cortical studies were performed in 19 children with renal transplants. There were 10 normal studies and 9 abnormal studies, 8 of which showed multiple large focal peripheral cortical defects. The following factors showed a positive correlation: (a) the ischemia time of the transplant kidney was significantly shorter in patients with normal studies; (b) cadaver grafts were more likely to have abnormal scan appearances than living related donor grafts; and (c) in four of the five patients with double renal arteries, the scans were abnormal in multiple sites. A possible pathophysiologic mechanism to explain these scan appearances is asymptomatic segmental graft infarction secondary to progressive vascular disease. These infarcts may be a long-term sequela of ischemic insult at the time of or prior to the insertion of the renal allograft.