NEW PROTOCOL OF CT CYSTOGRAPHY (CTC) WITH DUAL SOURCE TECHNIQUE IN DETECTION OF BLADDER LESION

Introduction & Objectives: To assess a new CT protocol of CTC and Virtual Cystoscopy with Dual Source technique in detection of bladder lesions using Cystoscopy with Photodynamic Diagnosis (PDDs) as reference standard. Materials & Methods: Thirty haematuric patients suspicious for bladder cancer and fourteen patients who had undergone transurethral resection of the bladder underwent CTC and Virtual Cystoscopy with multi detector CT and Dual Energy technique after administration of i.v. contrast agent. Patient population was divided into three groups on lesion size at PDDs cystoscopy. Results of the CT study were compared with those of conventional cystoscopy and PDDs cystoscopy. Results: PDD cystoscopy depicted 92 bladder lesions in the 44 patients examined. Sensitivity and specificity values of CTC and VC alone were constantly lower than those of the combined-approach (group 1: 93.25% and 92.54%; group 2: 100% and 100%; group 3: 100% and 100%, respectively). Regarding lesion size, it has been also demonstrate that multidetector-row CT performed with thin-slice reconstructions (1 mm) allow a good sensitivity in the detection of lesion over 1 mm. ROC analysis showed that the combined approach decreases the lower dimensional threshold for lesion detection (1.4 mm). The study of bladder wall after administration of c.a. and Dual Energy technique permit to distinguish superficial or infiltrative lesion in 89% of cases. Conclusions: CTC and VC are promising diagnostic approach for bladder cancers measuring in the range of 1-5 mm and to distinguish from superficial to infiltrative lesion. The main disadvantage of CTC and VC is the low sensitivity to depict flat lesions, as demonstrate on cystoscopy with PDD method. CTC can be used for the evaluation of haematuric patients confining standard cystoscopy to a therapeutical role.