الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Hematuria is defined as the presence of blood in urine. It may have a number of causes, the more common being urinary tract calculi, urinary tract infection, urinary tract neoplasms (including renal cell carcinoma and urothelial tumors), trauma to the urinary tract and renal parenchymal disease. The value of a hematuria work up should be measured against its cost and morbidity by ascertaining whether a significant source of hematuria is identified, whether diseases are discovered early in their course and whether effective treatment will be implemented based on diagnoses obtained. Evaluation of patients with hematuria frequently requires several imaging modalities including intravenous urography (IVU), ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), retrograde ureterography and pyelography, cystoscopy and ureteroscopy. Multi-slice CT urography performed with a combination of unenhanced, nephrographic-phase, and excretory-phase imaging can demonstrate a wide spectrum of disease in these patients with a single study. Unenhanced imaging provides optimal detection of calculi which is a common cause of hematuria. In addition, the combination of unenhanced and nephrographic-phase imaging provides outstanding evaluation of renal masses. Findings at excretory phase imaging mimic IVU findings and allow excellent evaluation of the collecting systems and ureters. Bladder disease, a one of common cause of hematuria, is often well seen on unenhanced or excretory-phase images, although cystoscopy may still be necessary.
Multi-slice CT offers several advantages for imaging of the urinary system: single breath-hold coverage of the entire urinary tract with absence of respiratory mis-registration, rapid imaging with optimum contrast medium opacification and reduced partial- volume effect as appropriate slices can be selected from the volumetric data.
In addition, acquisition of multiple thin overlapping slices provides excellent two-dimensional (2D) and three-dimensional (3D) reformations and facilitates virtual cystoscopy. These advantages have established MSCT as the current modality of choice for evaluation of painless gross or microscopic hematuria, thereby saving time, hospital visits and cost, and potentially shortening the duration of diagnostic evaluation for urinary tract pathology.
Although magnetic resonance urography (MRU) is the only other alternative study, which can image all the anatomic components of the urinary tract in a single test, its main disadvantages which have hindered its widespread usage in the evaluation of the urinary tract, is its inability to detect urinary tract calcifications, calculi and air; limited availability in comparison to MSCTU; and limited experience in interpretation of images.
It has been established that currently, MDCT is the most sensitive and specific test for the diagnosis of hematuria.