Multidetector CT Virtual Cystoscopy in Gross Painless Hematuria

Research Article

Austin Oncol. 2016; 1(1): 1003.

Multidetector CT Virtual Cystoscopy in Gross Painless Hematuria

Kemal Arda¹*, Hasan Aydin² and Ahmet Hakan Haliloglu³

¹Ankara Ataturk Training and Research Hospital Department of Radiology, Bilkent Ankara, Turkey

²Ankara Oncology Hospital, Department of Radiology, Demetevler, Ankara Turkey

³Ufuk University Dept of Urology, Balgat Ankara Turkey

*Corresponding author: Kemal Arda, Ankara Ataturk Training and Research Hospital Department of Radiology, Bilkent Ankara, Turkey

Received: December 09, 2015; Accepted: January 27, 2016; Published: January 29, 2016


Purpose: The objective of this study was to investigate the diagnostic efficiency of Multidetector CT (MDCT) based virtual cystoscopy in the assessment of bladder tumors in gross, painless hematuria.

Materials and Methods: 30 patients (21 men, 9 women) with gross, painless hematuria who had not had recent diagnosis were included in this prospective study. MDCT based virtual cystoscopy was performed using 16-slice multidetector CT scanner in the supine and prone positions. After axial scanning, the axial images were assessed, followed by coronal, and sagittal multi planar reconstruction of the images. In addition, by using volume rendering technical algorithms shaded the surface display MDCT based virtual cystoscopy was performed. In the multiplanar and 3-Dimensional images obtained, the existence, localization, morphological features, environment invasion, adjacent lymph nodes, and if any metastases of the abdomen were assessed. Then, all patients underwent conventional cystoscopy examination as the gold standard.

Results: In 10 cases, 24 bladder masses were detected by MDCT based virtual cystoscopy whereas 23 lesions (ranged from 0.33-5.8 cm) were depicted by conventional cystoscopy. Eleven of the 24 bladder masses measured less than 1 cm in maximum diameter. At MDCT based virtual cystoscopy, one patient with poor bladder distention, and severe trabeculation was wrongly diagnosed as tumor. Histopathologic diagnoses of 18 of the 23 bladder masses were transitional cell carcinoma, one patient with four masses was mixed tumor (transitional cell carcinoma + squamous cell carcinoma), and one was adenocarcinoma. The sensitivity, the specificity, negative predictive value, and positive predictive value of MDCT based virtual cystoscopy for detecting bladder carcinoma were % 100, % 95,2, % 100, and % 95,6 respectively. In addition to bladder pathologies, renal or ureter calculi, kidney or ureter mass, kidney cysts and lympadenopathies were investigated.

Conclusion: MDCT based virtual cystoscopy in the assessment of the bladder tumors is a non- invasive method that can be used in gross painless hematuria.

Keywords: Bladder tumors; Virtual cystoscopy; Painless hematuria


Gross, painless hematuria is the classical clinical sign of bladder malignancies [1-13]. The differential diagnosis of the hematuria frequently requires several imaging modalities [1]. Many imaging modalities such as Excretory-Urography (EU), ultrasonography, Computed Tomography (CT), retrograde ureterography, conventional cystoscopy, and ureteroscopy have been used in the evaluation of patients with hematuria [1]. Conventional cystoscopy is gold standard in the diagnosis, and plays a key role in follow-up of bladder malignancies. MDCT based virtual cystoscopy is new promising, alternative imaging technique for evaluation of bladder lesions that is noninvasive and has good patient acceptance [1-17]. The major limitation of the technique is the difficulty in depiction of small lesions.

CT may also be used for the diagnosis of the bladder disease, but the dome and the base of the bladder visualization are limited on the axial plane scanning. These areas can be easily evaluated in 3-Dimensional and multi planar reformatting images by using MDCT based virtual cystoscopy.

The objective of this study was to investigate the diagnostic efficiency of multidetector CT (MDCT) based virtual cystoscopy in the assessment of bladder tumors in gross, painless hematuria.

Materials and Methods

Patient population

Thirty patients (21 men, 9 women; age range 25-86 years; mean years ± SD, 54.7±17.4) presented with gross painless hematuria prospectively evaluated. They had been referred by the urology department for MDCT based virtual cystoscopy. The existence of haematuria was confirmed by urine analysis of each patients included the study. Patients who had kidney failure as determined by biochemical and urine analyses were excluded from the study. The study was approved by the hospital review board, and informed consent was obtained from all patients before the examination. All of the MDCT based virtual cystoscopic evaluations were performed before conventional cystoscopy and biopsy in order to avoid tumourlike lesions that could occur on bladder walls as a result of biopsy. The time interval between MDCT based virtual cystoscopy and conventional cystoscopy were less than 5 days.

CT technique

All CT examinations were performed with 16 slice Light speed CT scanner (GE Medical Systems, Milwaukee, Wis, USA), both in supine and prone positions with 120 kVp; section thickness of 1.25 mm; 0.5-second helical rotation time; and 250 mA.

Oral contrast material was not used. Unenhanced images were obtained from domes of the diaphragm to the symphysis pubis. One hundred milliliters of intravenous contrast media (Ioversol 350mgl/ Ml, Optiray, Covidien, Tyco, USA) was administered intravenously at a rate of 3mL/sec, with 60 second delay the nephrographic phase abdominopelvic contrast enhanced images were obtained. A 500 ml bag of normal saline solution was administered rapidly after the contrast material injection, to distend the urinary bladder. After bladder distention, before the virtual cystoscopic examination, all patients were asked to adopt supine and prone positions several times so that the contrast material and urine in the bladder could be adequately mixed to prevent sedimentation and fluid-fluid level of the contrast medium, and the urine in the bladder, and also to attenuate the entire bladder lumen homogeneously. After a scout view was obtained with the patient in the supine position to locate the bladder and confirm its adequate distention, single–breath-hold MDCT examination was performed both in supine and prone positions.

Source axial CT images were transferred to the workstation (AW 4.2 GE Medical Systems, Milwaukee, Wis, USA). MPR images 0.625 mm thick at 0.623 mm intervals were obtained in the transverse, coronal and sagittal planes to generate intraluminal views of the bladder. The time to generate these images was less than 60 seconds. Interactive endoscopic navigation using surface rendering algorithm were performed. During the interactive navigation the threshold values were manually adjusted for the pacification of the bladder. The lowest threshold level was determined as the highest value to differentiate the lumen from the wall or the mass on the axial images. The viewpoint of the observer was manipulated through 360 degrees in any axis to evaluate the internal surface of the bladder, especially the base of the bladder, which is difficult area for conventional cystoscopy.

Un-enhanced images thin-section obtained from the kidneys to the bladder demonstrate the dens opacification of the urinary tract.

Un-enhanced and reprographic-phase images were used for the characterization of the renal paranchimal abnormalities, particularly masses.

Source axial, MPR and MDCT based virtual images were prospectively interpreted, both separately and in combination, by two radiologists with 15 years and 4 years of experience in CT. These radiologists worked in concensus and were blinded to the results of conventional cystoscopy. The number, size, localization, and morphologic features of the lesions were studied. The bladder lesions were classified as polypoid, sessile, and areas of wall thickening. The time spent on study interpretation was approximately 10 minutes. The MDCT based virtual cystoscopy findings were compared with the conventional cystoscopy, which was considered as the gold standard. MDCT based virtual cystoscopy and conventional cystoscopy findings were correlated with histologic diagnosis.

Conventional cystoscopy

Conventional cystoscopy with a flexible cystoscope was performed on all patients, and biopsies of suspicious lesions were taken by urologist in the urology department. Techniques used for conventional cystoscopy included, in 24 patients, 2I F rigid cystoscopy (Karl Stor 2 Endoscope, Hopkins II, Berlin, Germany) with a 30º field of view. Number, location, size, morphology and pathologic findings of the lesions were studied.

Statistical analysis

Statistical analysis was performed according to the number of the lesions (not the number of patients) because each patient had one or multiple lesions. Using the conventional cystoscopic findings as the reference standard, the presence or absence of a bladder lesion at each site was evaluated on the MDCT based virtual cystoscopy together with multiplanar reconstruction images. We calculated the sensitivity, specificity, Positive Predictive Values (PPV), and Negative Predictive Values (NPV), and accuracy of virtual cystoscopy. NPV and PPV were calculated on a per patient basis: if at least one tumor per patient was detected on both virtual and conventional cystoscopy, the patient was counted as a true-positive. When tumors were not detected with either diagnostic method, we considered patients as true-negatives. If a tumor or tumor like lesion was detected by MDCT based virtual cystoscopy but not detected by conventional cystoscopy, the patient was counted as a false-positive.


MDCT based virtual cystoscopy

The procedure was well tolerated by all patients and no complication was reported. Mixing of the contrast material and urine was adequate on the supine scan in all patients. The bladder distention was not adequate in one patient.

Renal or ureteral calculi were detected in 6 of the cases. One solid renal mass and 13 cystic renal masses were detected on CT examination. In these twenty patients MDCT based virtual cystoscopy and conventional cystoscopy examinations were normal.

Five patients had a single bladder lesion (Figure 1-3), two patients had two bladder lesions, and three patients had four or more lesions on MDCT based virtual cystoscopy evaluation.