الفهرس 
Aim of the workOnly 14 pages are availabe for public view
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Abstract
Summary And Conclusion
Bladder carcinoma is the most common tumor among the lower urinary tract, accounting for 90% of cancer cases. Several imaging techniques are available to detect bladder neoplasia. However, there is no reliable method for tumor detection, and negative findings require cystoscopy.
Conventional cystoscopy represents the gold standard for diagnosis and local management of bladder carcinoma. However it has many draw backs such as intense discomfort for the patient and bleeding; furthermore, the high cost, invasiveness, and local complications such as infections and mechanical lesions are another well-known drawbacks. Additionally, conventional cystoscopy does not provide information about extravescical extensions of the tumors.
Recent advances in CT including software developments have led to the use of three dimensional (3D) imaging reconstruction techniques and allow CT urography and virtual endoscopy to be used in daily practice.
The main goal of virtual cystoscopy was to develop a non-invasive diagnostic tool that would be easily tolerated by the majority of patients, by producing images similar to those acquired by the conventional endoscopy.
At present virtual cystoscopy based on volumetric data obtained with thin section multislice CT and the use of perspective volume rendering technique, seems to be the most accurate radiological method regarding lesion detection in the urinary bladder.
In our study we tried to investigate the utility of the virtual cystoscopy in the detection of the bladder masses, and compared the findings to the gold standard conventional cystoscopy.
The main steps to perform virtual cystoscopy incorporate proper bladder distention with air after draining the residual urine through Foley catheter and scanning the patient in both supine and prone positions.
An excellent overview of the bladder masses was obtained in all cases and the results of virtual cystoscopy and conventional cystoscopy were comparable with excellent sensitivity rates of virtual cystoscopy in detection, localization and morphological description of the bladder lesions at variable sizes. The size of the masses ranged from 3 to 60 mm in diameter, including 10 lesions with a diameter of 1cm or less.
The high detection rate of the lesions is mainly attributed to the CT protocol used. Acquisition with thin collimation, creation of MPR images with no artifacts and virtual images of very good quality and excellent anatomic details facilitated detection of a large number of small tumors with a 16-MDCT scanner.
Generally speaking, virtual cystoscopy has several advantages, it is less invasive, less time consuming, requiring less equipment, with fewer patient preparation steps, allowing imaging of the urinary bladder in multiple planes. Also it can be used to evaluate areas of the urinary bladder difficult to assess with cystoscopy, such as the anterior wall, bladder neck and narrow-mouthed diverticulae.
On the other hand virtual cystoscopy has still some limitations: It is unable to depict flat lesions or mucosal color changes, does not allow for biopsy, it is unable to identify the origin and nature or depth of invasion of the bladder masses.
In conclusion, virtual CT cystoscopy is a promising technique for detection of bladder masses. However it is unlikely to replace conventional cystoscopy.
This minimally invasive method can be of value for screening, primary diagnosis and surveillance of bladder lesions.
For further development, hardware is needed for evaluation of bladder lesions.