Conventional Excretory Urography Research Articles

Imaging and Staging of Transitional Cell Carcinoma: Part 2, Upper Urinary Tract

Transitional cell carcinoma (TCC) of the upper urinary tract is a common malignancy affecting the genitourinary tract. It is commonly multifocal with a high incidence of recurrence requiring rigorous urothelial surveillance. In this article, we discuss the epidemiology, pathologic characteristics, and patterns of tumor spread. We illustrate and discuss the role of imaging in the diagnosis, staging, and surveillance of TCC of the renal pelvis and the ureter. The hallmark of TCC is multiplicity and recurrence. Nearly 2-4% of patients with bladder cancer develop upper tract TCC, but 40% of patients with upper tract TCC develop bladder cancer. Diagnosis of upper tract TCC is heavily dependent on imaging. Understanding the appearances of upper tract TCC on the different imaging techniques used is important in the accurate interpretation of imaging studies. Newer techniques such as CT urography are now increasingly used instead of conventional excretory urography in the surveillance of the upper tract in patients with bladder cancer.

The Role of Computerized Tomographic Urography in the Initial Evaluation of Hematuria

We determined the usefulness of computerized tomographic urography for the initial evaluation of patients with hematuria as an alternative to excretory urography. A total of 259 patients (140 men and 119 women), age range 20 to 100 (mean 59.4) years, underwent computerized tomographic urography for the evaluation of hematuria and were available for followup. A cohort of 253 patients (153 men, 100 women), age range 21 to 92 (mean 57.6) years, underwent conventional excretory urography and were evaluated for comparison. A source of hematuria was identified in 107 patients (41.3%) in the computerized tomographic urography cohort and in 103 patients (40.7%) in the excretory urography cohort. Computerized tomographic urography alone identified a source of hematuria in 25.5% of these patients with the most commonly diagnosed lesions being renal calculi (18.9%), ureteral calculi (2.7%) and renal pelvic masses (2.3%) in the upper tract (0.94 sensitivity), and bladder masses (8.1%), prostatic abnormalities (5.4%) and inflammatory disorders (3.5%) in the lower tract (0.40 sensitivity, 0.99 specificity). The overall detection rate (19.5%), most commonly diagnosed lesions, and lower urinary tract sensitivity and specificity were similar in the excretory urography cohort. However, excretory urography exhibited a markedly lower sensitivity in detecting upper tract lesions (0.50). Computerized tomographic urography exhibited a significantly higher sensitivity than conventional excretory urography in detecting upper tract pathology (94.1% vs 50%). However, sensitivity for detecting lower tract lesions was low (40% or less), suggesting that computerized tomographic urography offers a comprehensive alternative to excretory urography but does not obviate the need for adjunctive cystourethroscopy for accurate evaluation of the lower urinary tract.

Imaging for renal tumors.

The present review summarizes current developments in the imaging of renal tumors. Computed tomography (CT), magnetic resonance imaging, and ultrasound are used for diagnosing, characterizing, and staging renal tumors. Recent advances have been made in many areas, but the most significant changes have occurred in helical CT. The traditional roles for CT and magnetic resonance imaging have been expanded to include the use of three-dimensional CT and magnetic resonance imaging as surgical planning tools. Three-phase CT scans are commonly performed for detection, characterization, and staging of renal lesions, but pelvic CT is probably not needed for preoperative staging. Three-phase CT scans are more sensitive for characterization and for identifying the renal vasculature. Enhancement characteristics on these scans can help to distinguish between different tumor types. Finally, CT urography is a promising alternative to conventional excretory urography, with the potential to simplify the imaging evaluation of patients with hematuria. Although ultrasound and magnetic resonance imaging have many indications for imaging renal tumors, CT, with new uses and improved diagnostic capabilities, remains the gold standard in renal imaging.

State-of-the-art magnetic resonance imaging of the kidneys and upper urinary tract.

State-of-the-art magnetic resonance imaging (MRI) is an excellent examination in several clinical contexts of interest to endourologists. First, it offers a one-stop imaging examination of prospective renal donors, obviating the need for arteriography and conventional excretory urography. Second, it reliably depicts urinary tract obstruction and can usually distinguish acute from chronic obstruction, although it is not as sensitive as helical CT in detecting small, nonobstructing stones. Third, it is an excellent examination for characterizing renal masses, especially complex cystic masses, and for surgical planning. Because MRI does not use ionizing radiation and because gadolinium contrast agents are essentially non-nephrotoxic, MRI is especially useful in children, women of childbearing age, and patients with renal insufficiency or renal allografts. Future developments will likely include MR "fluoroscopy," which will provide real-time imaging guidance for interventional procedures in the urinary tract.

Gadolinium-Enhanced Excretory MR Urography After Low-Dose Diuretic Injection: Comparison With Conventional Excretory Urography

PURPOSE: To evaluate the clinical utility and morphologic accuracy of gadolinium-enhanced excretory magnetic resonance (MR) urography after low-dose diuretic injection and to correlate the results with those of conventional urography. MATERIALS AND METHODS: In 71 patients with urologic symptoms, excretory MR urography was performed after intravenous injection of 5-10 mg furosemide and, 30-60 seconds later, 0.1 mmol of gadopentetate dimeglumine per kilogram of body weight. The MR urograms were interpreted by three radiologists, who were blinded to the clinical outcome, and subsequently compared with conventional urograms. RESULTS: Injection of furosemide before contrast material led to rapid, uniform gadolinium distribution inside a sufficiently distended collecting system such that there was no excessive concentration of gadolinium in the urine. In patients with normal or moderately reduced excretory function, this effect allowed complete visualization of the urinary tract within 5-20 minutes of contrast ...

UNENHANCED HELICAL COMPUTERIZED TOMOGRAPHY FOR THE EVALUATION OF PATIENTS WITH ACUTE FLANK PAIN

Purpose We determined the value of unenhanced helical computerized tomography (CT) in the diagnosis of acute flank pain in 105 patients evaluated for suspected stone disease. Materials and Methods Noncontrasted spiral CT was done in 105 consecutive patients seen in our emergency department to evaluate acute flank pain. All CT studies were reviewed for the presence of ureteral or renal calculi, perinephric or periureteral stranding, presence and degree of pelvicalicectasis or other radiological findings. If necessary, an excretory urogram was performed to confirm the presence or absence of urinary stones. Patients were followed to determine clinical outcome including the need for urological intervention. Results Of the 49 patients determined to have stones 24 (49%) had spontaneous stone passage, 10 (20%) had improved symptoms without documented stone passage and 14 (29%) required surgical intervention. In 29 of 51 patients (57%) with negative CT readings for stone disease a diagnosis was established by other intra-abdominal findings. In 21 patients (41%) no clinical diagnosis could be established, and 1 scan in a patient with a distal ureteral calculus was interpreted as falsely positive. These findings yielded a sensitivity of 98%, specificity 98% and overall accuracy 96% for diagnosing ureteral stones. Conclusions Despite the limitations of helical CT in evaluating renal function and nonobstructing ureteral calculi, noncontrasted CT is a sensitive imaging modality for the detection of urinary tract calculi and obstruction. The majority of our patients required no further imaging to determine the need for urological intervention. At our institution spiral CT has become the standard method to evaluate patients with acute flank pain leading to more rapid turnover in the emergency department at similar or even reduced cost to conventional excretory urography.

Magnetic resonance urography. First clinical results

We report our preliminary results using a new magnetic resonance imaging technique for visualization of the urinary tract. Using the paramagnetic contrast medium gadolinium diethylene triamine penta-acetic acid (DTPA), we were able to obtain images of the urinary tract comparable to those obtained by conventional excretory urography. The major advantage of our technique is that besides good morphologic visualization, the excretion of gadolinium-DTPA can be studied simultaneously. We demonstrate our preliminary results in selected cases.

Contemporary Imaging of Renal Inflammatory Disease

In addition to plain films and conventional excretory urography, ultrasound, computed tomography, and radionuclide scanning may contribute to the assessment of a wide spectrum of renal inflammatory diseases. This article discusses the role of contemporary imaging modalities in the diagnosis and management of patients with renal inflammatory lesions, including acute focal and diffuse bacterial infections, intra- and extrarenal abscess collections, pyonephrosis, xanthogranulomatous pyelonephritis, fungal infection, tuberculosis, and malakoplakia of the upper urinary tract.

Digital nephropyelography following intravenous renal digital subtraction angiography.

A 14-inch image intensifier designed for digital radiography has made feasible adjunctive evaluation of the renal parenchyma and collecting structures following intravenous digital subtraction angiography (DSA). Initial experiments with rabbits showed digital nephrography to be superior to film-based nephrotomography in terms of renal conspicuity and imaging flexibility. Preliminary experience with 30 patients undergoing DSA reaffirms the suitability of this method for the evaluation of renal anatomy and function. Only about half the amount of contrast material needed for conventional excretory urography is required.

Intravenous Renal Angiography Revisited

A non-catheter technique to visualize the renal arteries during conventional excretory urography is re-emphasized. By rapid injection of the contrast agent and immediate filming satisfactory visualization can be obtained in many cases. This technique is useful in the evaluation of vascular impressions and other urographic findings when intra-arterial catheter examination is not indicated.

Excretory urographic localization of adrenal cortical tumors and pheochromocytomas.

An excretory urographic evaluation of 124 surgically proved adrenal tumors comprising 65 pheochromocytomas, 36 cortical adenomas and 23 cortical carcinomas is reported. The addition of linear tomography improved the diagnostic accuracy over conventional excretory urography. All types of tomographic examinations demonstrated at least 70% of adrenal tumors. Excretory urographic procedures are relatively safe, simple and economical and should be used as the initial step in attempting to localize clinically suspected and chemically diagnosed adrenal tumors.