Which retrograde procedure involves the examination of ureters and renal Pelviss?
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Imaging tests are often used to evaluate patients with renal and urologic disorders. Show IVU (sometimes called IVP, for intravenous pyelography) has been largely superseded by rapid multidimensional CT and MRI with or without a contrast agent. When IVU is done, abdominal compression may improve visualization of the renal pelvis and
proximal ureters (with application) and distal ureters (after release). Additional x-rays at 12 and 24 hours after contrast administration may be indicated for detection of postrenal obstruction or hydronephrosis. When retrograde urography is unsuccessful (eg, because of tumor obstruction at the bladder level) When large kidney
calculi requiring percutaneous surgery must be evaluated When transitional cell carcinoma of the upper collecting system is suspected When patients cannot tolerate general anesthesia or the degree of sedation required for retrograde urography It is also useful for detailed examination of the pelvicaliceal collecting system and ureters to check for injury, stricture, or fistula. Overdistention and backflow from a kidney into the venous system may distort calyces and obscure details. Risk of infection is higher than that with other types of urography. Acute ureteral edema and secondary stricture formation are rare complications.
Voiding cystourethrography is done during urination and is primarily used to image the posterior urethra (eg, for strictures or valves). No patient preparation is necessary. Adverse effects include UTIs and urosepsis. Conventional catheter angiography has been largely replaced by noninvasive vascular imaging (eg, magnetic resonance angiography, CT angiography, ultrasonography, radionuclide scanning). Remaining indications include renal vein renin imaging and, among patients with renal artery stenosis, angioplasty and stent placement. Arteriography is also rarely used for evaluation and treatment of renal hemorrhage and before kidney-sparing surgery. Digital subtraction angiography is no longer used when rapid-sequence multidimensional CT or helical (spiral) CT is available. Ultrasonography can provide useful images of many genitourinary structures without exposing patients to ionizing radiation. Images are interpreted as they are acquired, so the technician can focus on concerning areas and obtain additional information if necessary. Its main disadvantages are the need for a skilled operator and the time required. A full bladder helps provide better images of certain structures but no other preparation is needed. Structures that can be imaged and common indications include the following:
Also, due to the risk of nephrogenic systemic fibrosis, MRI with gadolinium contrast is contraindicated in patients with glomerular filtration rate (GFR) < 30 mL/min.
Newly available nuclear positron emission tomographic (PET) agents can detect metastatic prostate cancer. Routine FDG PET scans are not very useful for most cases of prostate cancer but can be useful for other genitourinary tumors such as kidney or testicular cancer. Newer PET imaging includes targeting PSMA (prostate-specific membrane antigen) on the surface of prostate cancer cells. Indications of retrograde pyelography include the following: [1] [2]
Retrograde pyelography plays an important role in the management of ureteropelvic junction obstruction (UPJO). Once UPJO has been diagnosed, retrograde pyelography is used to confirm the diagnosis and to determine the exact location and nature of the obstruction. This procedure can be done prior to or at the time of planned intervention for UPJO. Being able to accurately locate and define the obstruction is extremely important for the urologist as it will dictate what type of procedure to perform to alleviate the obstruction. Retrograde pyelography allows the physician to determine the length of ureteral stricture at the ureteropelvic junction, to determine whether a true stricture is present, and to measure the length of stricture. These criteria will further determine if an endoscopic incision can be done in the form of an endopyelotomy versus an open procedure and, in some cases, if further reconstructive options are needed if the gap of diseased ureter is substantial. Pathology within the ureter may appear as a filling defect when contrast is introduced within the ureter. Urolithiasis is primarily diagnosed with noncontrast CT scanning. [3, 4] Retrograde pyelography is used to determine the exact location of the calculi within the collecting system. Once the location of the stone is confirmed, the stone is fragmented and can be extracted. Retrograde pyelography can also aid in the detection of any large residual stone fragment following laser lithotripsy.  Masses within the ureter also present as a filling defect. However, the shape of the filling defect can differ from that of stones. A benign lesion such as a fibroepithelial polyp typically appears as a long smooth filling defect and is sometimes referred to as vermiform in appearance. [5] Malignant tumors such as upper-tract transitional cell carcinoma can present as an irregularly shaped defect depending on the shape of the tumor. When placing a stent, it is always important to ensure that it is properly placed before ending the procedure. This holds even more importance when dealing with patients with a duplicated collecting system. In specific instances, shockwave lithotripsy is a viable option for stone fragmentation. [6] When the stone is radiolucent and not visible on fluoroscopy (eg, uric acid stones), ultrasonography can be used with an additional option of using contrast material. In most instances, if there is significant ureteral obstruction, intravenous contrast may not be helpful to delineate the site of ureteral obstruction. In these instances, retrograde pyelography is performed to localize the stone for shockwave lithotripsy. The contrast that is used for retrograde pyelography is the same that is used for excretory urography (intravenous urography). Contrast is categorized by osmolality, of which there are 3 groups: isoosmolar, low osmolar, and high osmolar. As osmolarity decreases, radiographic density increases. [7] For retrograde pyelography, the contrast is typically diluted to 50% using sterile water by the physician. Diluting the contrast ensures that even the most subtle filling defects will not be missed. [1] Which procedure involves the examination of the uterus and renal pelvis is?During a ureteroscopy, the urologist will focus on viewing the ureter and lining of the kidney, known as the renal pelvis.
Which of the following diagnostic tests is used to examine the renal pelvis and ureters?A CT urogram is used to examine the kidneys, ureters and bladder. It lets your doctor see the size and shape of these structures to determine if they're working properly and to look for any signs of disease that may affect your urinary system.
Which procedure involves the examination of the ureters and the renal pelvis quizlet?Pyelogram. A pyelogram is a retrograde examination of the ureters and the pelvis of both kidneys.
What is retrograde catheterization ureter?Retrograde pyelography is a form of x-ray used to get detailed pictures of the ureters and kidneys. Retrograde pyelography uses a special dye ("contrast agent") injected into the ureters.
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