Radiologische Beckendiagnostik

Prostate cancer, bladder cancer, and pelvic floor weakness are among the most common diseases of the pelvis. Cardinal symptoms include painless macrohematuria in bladder cancer and urinary and fecal incontinence in pelvic floor weakness. Suspicion of prostate cancer currently is most frequently raised when the serum concentration of prostate-specific antigen is pathologically elevated. Besides extensive clinical and invasive diagnosis, clinical imaging is frequently applied for the localization, locoregional staging, and diagnosis of recurrence of prostate cancer and invasive bladder cancer, and in clinically difficult cases of cystocele, enterocele, rectocele, descensus or prolapse of vagina, uterus, and rectum, and rectal intussusception. Magnetic resonance imaging with T2-weighted TSE or FSE images in several planes combined with either axial, T1-weighted images and MR spectroscopy for the prostate, dynamic contrast-enhanced T1-weighted images for the urinary bladder, or dynamic T2-weighted functional images for pelvic floor incontinence are particularly well suited as clinical imaging methods.     

Dynamic MR imaging of recurrent postoperative cervical cancer

The value of dynamic-contrast enhanced MR imaging using FLASH technique was studied in 13 patients with postoperative recurrent cervical cancer verified histopathology and in 9 patients without recurrence. Dynamic FLASH imaging and conventional spin-echo T1- and T2-weighted sequences were compared in a prospective fashion with regard to accuracy of the diagnosis of recurrent tumor using biopsy results as the gold standard. The contrast between the recurrent tumor and the surrounding pelvic tissues was also analyzed. The accuracy of depicting recurrent tumor on dynamic images (82%) was superior to that of pre- and postcontrast T1-weighted images and T2-weighted images (64%, 68%, and 64%, respectively). The contrast between the recurrent tumor and pelvic fat was greater on precontrast T1-weighted and dynamic images than on T2-weighted and postcontrast T1-weighted images. The dynamic images clearly showed involvement of the surrounding pelvic organs, because enhancement was observed exclusively in the tumor in the early dynamic phase. Accuracy regarding involvement of the urinary bladder or rectal wall on pre- and postcontrast T1-weighted images and T2-weighted images was lower than that on the dynamic images. Dynamic MR imaging has potential for use in the detection and evaluation of the extent of recurrent postoperative cervical cancer.     

Gadolinium-enhanced MR imaging, T2-weighted MR imaging, and transurethral ultrasonography

PURPOSE: To assess the value and problems of dynamic gadolinium-enhanced MR imaging, T2-weighted MR imaging, and transurethral ultrasonography(TUUS) in staging of urinary bladder cancer. MATERIALS AND METHODS: Dynamic gadolinium-enhanced MR imaging and FSE T2-weighted MR imaging of 64 patients with urinary bladder cancer who subsequently had surgery were retrospectively reviewed and compared with TUUS findings. RESULTS: Specificity for muscular invasion was 90.5% with TUUS, significantly better than with dynamic MR imaging (64.9%) (p < 0.05). The rates of overestimation of superficial cancer(pT1) with dynamic MRI and T2-weighted MR imaging were 35.1%(13/37) and 24.3%(9/37), respectively. The staging accuracy of invasive cancer(pT2 or over) was 85.2% with dynamic MR imaging, which was better than the rate of 75.0% achieved with T2-weighted MR imaging. CONCLUSION: Although TUUS was a better modality for diagnosing superficial cancer(pT1), dynamic MR imaging was found to be better for diagnosing invasive(pT2 or over) cancer.     

Practical MR imaging of female pelvic floor weakness.

Pelvic floor weakness is common in middle-aged and elderly parous women and is often associated with stress incontinence, uterine prolapse, constipation, and incomplete defecation. Most patients with incontinence and minimal pelvic floor weakness can be treated based on physical examination and basic urodynamic findings. However, in women with symptoms of multicompartment involvement for whom a complex repair is planned or who have undergone previous repairs, magnetic resonance (MR) imaging can be a useful preoperative planning tool. The MR imaging evaluation is performed with the patient in the supine position, without contrast agents, and within 15 minutes. A multicoil array and a rapid half-Fourier T2-weighted imaging sequence are used to obtain sagittal images while the patient is at rest and during pelvic strain, followed by axial images. On these images, the radiologist identifies the pubococcygeal line (which represents the level of the pelvic floor), the H and M lines (which are helpful for confirming pelvic floor laxity), and the angle of the levator plate with the pubococcygeal line (which is helpful for identifying small bowel prolapse). In the appropriate patient, MR images provide relatively easy three-dimensional conceptualization of the pelvic floor and can significantly influence treatment planning.     

Ultrafast MR imaging of the pelvic floor

OBJECTIVE: The aim of this study was to compare pelvic floor anatomy and laxity at rest and on straining (Valsalva's maneuver) using dynamic ultrafast MR imaging in women who were continent versus those with stress incontinence differing in obstetric history. MATERIALS AND METHODS: Thirty continent women were divided into three equal groups (nulliparous, previous cesarean delivery, previous vaginal delivery) and compared with 10 women with stress-incontinence with a history of at least one vaginal delivery. MR imaging of the pelvic floor at rest and on maximal strain was performed, using axial T2-weighted fast spin-echo images followed by sagittal ultrafast T2-weighted single-shot fast spin-echo sequences. Mean population age (age range, 22-45 years; mean +/- SD, 36 +/- 5.4 years), was similar in the four groups, as was parity in the three parous groups. RESULTS: Mean distances between the bladder floor and pubococcygeal line at rest did not differ between the four groups. On straining, bladder floor descent was 1.1 +/- 0.9, 1.0 +/- 1.1, and 1.9 +/- 0.9 cm in continent nulliparous, cesarean delivery, and vaginal delivery women, respectively, versus 3.2 +/- 1.0 cm in incontinent women (p = 0.0005). Cervical descent was greater in incontinent versus nulliparous women (p = 0.0019). Bladder floor descent was greater in the continent vaginal delivery group than in continent cesarean delivery control patients (p = 0.04). In patients with stress incontinence, symptoms did not correlate with amplitude of descent. The right levator muscle was thinner overall than the left, regardless of frequency direction (p = 0.001). CONCLUSION: Ultrafast MR imaging using the T2-weighted single-shot fast spin-echo sequence allows dynamic evaluation of the pelvic compartments at maximal strain with no need for contrast medium. Pelvic floor laxity and supporting fascia abnormalities were most common in patients with stress incontinence followed by continent women with a history of vaginal delivery. The results are therefore compatible with the hypothesis of vaginal delivery as a contributory factor to stress incontinence in older parous women.     

Dynamic MR imaging of the pelvic floor performed with patient sitting in an open-magnet unit versus with patient supine in a closed-magnet unit

PURPOSE: To compare open-magnet magnetic resonance (MR) imaging performed with the patient sitting with dynamic closed-magnet MR imaging of the pelvic floor performed with the patient supine. MATERIALS AND METHODS: Thirty-eight patients underwent dynamic 1.5-T closed-magnet pelvic floor MR imaging while in the supine position. Midsagittal T2-weighted single-shot fast spin-echo and T1-weighted multiphase spoiled gradient-recalled-echo (SPGR) MR images were obtained before and after rectal contrast agent administration, respectively, with the patient at rest, straining, and maximally contracting the sphincter. Subsequently, the patient was transferred to an open 0.5-T system. Midsagittal multiphase T1-weighted SPGR MR images were then obtained every 2 seconds with the patient sitting while at rest, maximally contracting the sphincter, straining, and defecating. Images were analyzed with regard to presence of enteroceles, anterior rectoceles, intussusceptions, rectal descents, bladder descents, and vaginal vault descents. RESULTS: All intussusceptions were missed at supine MR imaging. With sitting MR imaging as the reference standard, the sensitivity of supine MR imaging was 79% for depiction of bladder descents. When MR findings were graded and clinically irrelevant MR findings were excluded, sensitivity increased to 100% for depiction of bladder descents and anterior rectoceles and to 96% for depiction of rectal descents. CONCLUSION: Dynamic supine MR imaging performed with a closed-configuration unit before and after rectal contrast agent administration appears to be an alternative to sitting MR defecography performed with an open-configuration unit for diagnosis of clinically relevant pelvic floor abnormalities.     

Dynamic pelvic floor MR imaging at 3 T in patients with clinical signs of urinary incontinence-preliminary results

To prospectively evaluate feasibility, image quality and diagnostic accuracy of dynamic MR imaging the pelvic floor at 3.0 T in patients with urinary incontinence and to compare these results with those of MRI performed at 1.5 T. Ten patients with the diagnosis of urinary incontinence (clinical symptoms, clinical examination, pelvic ultrasound) were examined with a dynamic balanced FFE (B-FFE) sequence at 1.5 T and 3.0 T on the same day in a randomized order. Spatial (1.5 × 1.5 × 8 mm) and temporal (0.44 s) resolution at 3.0 T were comparable to the 1.5-T B-FFE sequence. Two radiologists assessed visual signal to noise (three-point scale), artefact level (five-point scale) and final MR diagnoses with regard to pelvic floor weakness (independent analysis). The diagnoses obtained at 1.5-T field strength and the results of the clinical tests served as standard of reference. In addition, ROI-based quantitative measurements were performed to assess different tissue contrasts at both field strengths. Data were analyzed for statistical differences by using the Wilcoxon's matched pairs test and the marginal homogeneity test. Visual signal to noise was rated higher at 3.0 T for all ten studies by both radiologists. With regard to artefact level, there was no statistically significant difference between the studies obtained at 3.0 T as compared to the corresponding 1.5-T studies (marginal homogeneity test: p = 0.18 for reviewer 1 and 0.41 for reviewer 2). Mean artefact level was rated minor to moderate by both reviewers for both field strengths (excellent interobserver agreement with Kendall-W value of 0.973). Except for a higher tissue contrast between fat and urethra at 1.5 T, there were no statistically significant differences between tissue contrast at 1.5 T as compared to 3.0 T (Wilcoxon's test). Final MR diagnoses regarding pelvic floor weakness did not differ between 3.0-T and 1.5-T field strength and correlated well with the results of the clinical tests. Dynamic pelvic floor MR imaging is feasible at 3.0 T. Our preliminary data indicate that evaluation of pelvic floor disease seems to be possible with 3.0 T equally well as compared to 1.5 T.     

Brachytherapy for prostate cancer: endorectal MR imaging of local treatment-related changes

PURPOSE: To determine the local treatment-related endorectal magnetic resonance (MR) imaging findings after brachytherapy for prostate cancer. MATERIALS AND METHODS: Endorectal MR imaging was performed in 35 consecutive patients at a mean interval of 12 months (range, 1-31 months) after brachytherapy for prostate cancer. Transverse T1-weighted and high-spatial-resolution transverse and coronal T2-weighted images were acquired. Two readers reviewed MR image quality and findings, with discrepancies resolved by consensus. Posttreatment urinary symptoms in patients (n = 24) were documented by using chart review. RESULTS: All studies were of diagnostic quality. On T2-weighted images, prostatic findings consisted of diffuse low signal intensity (n = 35) and indistinct zonal anatomy (n = 34). Intra- and extraprostatic seed locations could be distinguished. The most common extraprostatic site of seed implantation was the neurovascular bundles (n = 35, bilateral in 32). The most common extraprostatic tissue finding was increased signal intensity on T2-weighted images in the levator ani muscle (n = 34) and the genitourinary diaphragm (n = 28). Postbrachytherapy urinary symptoms showed no demonstrable correlation with periurethral or genitourinary diaphragm seed implantation or with signal intensity change in the genitourinary diaphragm. CONCLUSION: Endorectal MR imaging can be used to evaluate seed distribution and to demonstrate treatment-related changes after brachytherapy for prostate cancer.     

Magnetic resonance imaging for diagnosis and follow-up of genitourinary, pelvic, and perineal rhabdomyosarcoma.

Magnetic resonance (MR) imaging, ultrasound, and computed tomography (CT) were performed for diagnosis and follow-up of rhabdomyosarcoma (RMS) arising from the genitourinary tract in five children, pelvic musculature in one, and the perineum in three others. MR imaging performed at 1.0 T included the following: spin-density-, T1-, and T2-weighted images in all nine patients; gadopentatate dimeglumine (Gd-DTPA)-enhanced T1-weighted images in five; and short TI inversion recovery (STIR) images in two children. Longitudinal T1-weighted images were of additional help in localizing the primary tumor at diagnosis and detecting local spread. Residual or recurrent disease within the bladder was best detected by spin-density images. Gd-DTPA enhancement improved contrast in two studies, but paramagnetic artifacts obscured intravesical lesions in three other studies. STIR images disclosed pelvic and retroperitoneal lymphadenopathy. MR imaging is recommended as the key method of diagnosis and follow-up of pelvic RMS.     

Magnetic resonance imaging for diagnosis and follow-up of genitourinary,pelvic, and perineal rhabdomyosarcoma

Magnetic resonance (MR) imaging, ultrasound, and computed tomography (CT) were performed for diagnosis and follow-up of rhabdomyosarcoma (RMS) arising from the genitourinary tract in five children, pelvic musculature in one, and the perineum in three others. MR imaging performed at 1.0 T included the following: spin-density-, T1-, and T2-weighted images in all nine patients; gadopentatate dimeglumine (Gd-DTPA)-enhanced T1-weighted images in five; and short TI inversion recovery (STIR) images in two children. Longitudinal T1-weighted images were of additional help in localizing the primary tumor at diagnosis and detecting local spread. Residual or recurrent disease within the bladder was best detected by spin-density images. Gd-DTPA enhancement improved contrast in two studies, but paramagnetic artifacts obscured intravesical lesions in three other studies. STIR images disclosed pelvic and retroperitoneal lymphadenopathy. MR imaging is recommended as the key method of diagnosis and follow-up of pelvic RMS.     

Localization of prostate cancer using 3T MRI: comparison of T2-weighted and dynamic contrast-enhanced imaging

OBJECTIVE: To compare dynamic contrast-enhanced imaging and T2-weighted imaging using a 3T MR unit for the localization of prostate cancer. METHODS: Twenty consecutive patients with biopsy-proven prostate cancer underwent both T2-weighted imaging and dynamic contrast-enhanced imaging. At T2-weighted imaging and dynamic contrast-enhanced imaging, the presence or absence of prostate cancer confined within the prostate without extracapsular or adjacent organ invasion was evaluated in the peripheral zones of base, mid-gland, and apex on each side. Final decisions on prostate cancer localization were made by consensus between two radiologists. Degrees of depiction of tumor borders were graded as poor, fair, or excellent. RESULTS: Prostate cancer was pathologically detected in 64 (53%) of 120 peripheral zone areas. The sensitivity, specificity, and accuracy for prostate cancer detection were 55%, 88% and 70% for T2-weighted imaging and 73%, 77%, and 75% for dynamic contrast-enhanced imaging, respectively. Three cancer areas were detected only by T2-weighted imaging, 15 only by dynamic contrast-enhanced imaging, and 34 by both T2-weighted imaging and dynamic contrast-enhanced imaging. A fair or excellent degree at depicting tumor border was achieved in 67% by T2-weighted imaging and in 90% by dynamic contrast-enhanced imaging (P<0.05). CONCLUSIONS: Dynamic contrast-enhanced imaging at 3T MRI is superior to T2-weighted imaging for the detection and depiction of prostate cancer and thus is likely to be more useful for preoperative staging.     

Dynamic MRI of bladder cancer: evaluation of staging accuracy

OBJECTIVE: The purpose of this study was to evaluate the accuracy of gadoliniumenhanced MRI in staging bladder cancer in a series of patients with surgically proven bladder cancer. MATERIALS AND METHODS: Seventy-one patients with biopsy-proven bladder cancer underwent MRI on a 1.5-T scanner with a phased-array pelvic coil. Conventional T1-weighted spin-echo, T2-weighted spin-echo, and unenhanced and enhanced (0.1 mmol/kg gadolinium) fast spoiled gradient-echo images with fat suppression were obtained. Two blinded reviewers evaluated the MR images and assigned a stage that was compared with the pathologic stage (n = 67) or with clinical follow-up for at least 2 years after MRI (n = 4). RESULTS: Agreement among the reviewers was good in assigning a radiologic stage for bladder cancer (kappa = 0.80). On a stage-by-stage basis, MRI accuracy was 62%, and overstaging was the most common error (32%). Staging accuracy improved to 85% and 82% in differentiating superficial from invasive tumors and organ-confined from non-organ-confined tumors, respectively. The time interval between MRI and transurethral resection (/=61 days) was not a statistically significant factor in differentiating superficial from invasive and organ-confined from non-organ-confined tumors (p > 0.05). MRI accuracy in staging transitional cell carcinoma was not significantly different from that obtained in staging non-transitional cell carcinoma (p > 0.05). CONCLUSION: MRI shows good reproducibility between reviewers for staging bladder cancer. Although overall staging accuracy was only moderate, the accuracy for differentiating superficial versus invasive disease and organ-confined versus non-organ-confined disease was high.     

Sectional depiction of the pelvic floor by CT, MR imaging and sheet plastination: computer-aided correlation and 3D model

The structures of the pelvic floor are clinically important but difficult to assess. To facilitate the understanding of the complicated pelvic floor anatomy on sectional images obtained by CT and MR imaging, and to make the representation more vivid, a computer-aided 3D model was created from a male and a female torso to develop a teaching tool. A male and a female cadaver torso were investigated by means of CT, MR imaging, and serial-section sheet plastination. A 3D reconstruction of the pelvic floor and adjacent structures was performed by fusion of CT and MR imaging data sets with sheet plastination sections. Corresponding sections from all three methods could be compared and visualized in their 3D context. Sheet plastination allows distinction of connective tissue, muscles, and pelvic organs down to a microscopic level. In combination with CT, MR imaging, and sheet plastination a 3D model of the pelvic floor offers a better understanding of the complex pelvic anatomy. This knowledge may be applied in the diagnostic imaging of urinary incontinence or prolapse and prior to prostate surgery. Received: 18 January 2000 Revised: 1 June 2000 Accepted: 6 June 2000     

Evaluation of T2-weighted and dynamic contrast-enhanced MRI in localizing prostate cancer before repeat biopsy

We assessed the accuracy of T2-weighted (T2w) and dynamic contrast-enhanced (DCE) 1.5-T magnetic resonance imaging (MRI) in localizing prostate cancer before transrectal ultrasound-guided repeat biopsy. Ninety-three patients with abnormal PSA level and negative prostate biopsy underwent T2w and DCE prostate MRI using pelvic coil before repeat biopsy. T2w and DCE images were interpreted using visual criteria only. MR results were correlated with repeat biopsy findings in ten prostate sectors. Repeat biopsy found prostate cancer in 23 patients (24.7%) and 44 sectors (6.6%). At per patient analysis, the sensitivity, specificity, positive and negative predictive values were 47.8%, 44.3%, 20.4% and 79.5% for T2w imaging and 82.6%, 20%, 24.4% and 93.3% for DCE imaging. When all suspicious areas (on T2w or DCE imaging) were taken into account, a sensitivity of 82.6% and a negative predictive value of 100% could be achieved. At per sector analysis, DCE imaging was significantly less specific (83.5% vs. 89.7%, p < 0.002) than T2w imaging; it was more sensitive (52.4% vs. 32.1%), but the difference was hardly significant (p = 0.09). T2w and DCE MRI using pelvic coil and visual diagnostic criteria can guide prostate repeat biopsy, with a good sensitivity and NPV.     

The value of hyoscine butylbromide in pelvic MRI

AIM: To evaluate the effect of hyoscine butylbromide (HBB) on image quality and lesion and organ visualization in pelvic magnetic resonance imaging (MRI) MATERIALS AND METHODS: A prospective, ethically approved study was undertaken of 47 patients attending for pelvic MRI at a cancer centre. T2-weighted transverse and sagittal sequences were performed before and after intravenous injection of 20 mg HBB. Three radiologists independently scored anonymized image series for overall image quality, visualization of pelvic lesions and visualization of individual pelvic organs. Statistical analysis was performed to assess improvements in radiologists' scores post-HBB administration. Radiologists also assessed pre-HBB administration T1-weighted images for degree of bowel peristalsis to determine whether this could predict improvement in post-HBB T2-weighted image scores. Side effects of HBB were recorded using a patient questionnaire. RESULTS: Radiologists' scores for image quality and lesion visualization were significantly higher on the post-HBB administration T2-weighted series (p<0.0005). Scores for the visualization of the bladder, rectum, pelvic bowel, prostate, and seminal vesicles (all p<0.0005), cervix (p=0.019) and vagina (p=0.0001) were also significantly higher post-HBB administration. Scores for the degree of peristalsis on T1-weighted images were not related to improvement in image quality or lesion visualization on T2-weighted images post-HBB administration. Side effects of HBB were mild and self-limiting. CONCLUSION: Intravenous HBB administration improves image quality and lesion visualization in oncological pelvic MRI and is recommended for routine use.     

Prostate cancer imaging

As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. Magnetic resonance imaging (MRI) may enhance the staging of prostate cancer compared with clinical evaluation, transrectal ultrasound, or computed tomography (CT), and allows concurrent evaluation of prostatic, periprostatic, and pelvic anatomy. In clinical practice, the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with MR spectroscopic imaging (MRSI) is improving the evaluation of cancer location, size, and extent, while providing an indication of tumor aggressiveness. Pretreatment knowledge of these prognostic variables is essential for achieving minimally invasive, patient-specific therapy.     

MRI对前列腺癌及邻近受累结构的诊断价值

目的探讨MRI对前列腺癌及邻近受累结构的诊断价值。方法回顺性分析55例经穿刺或F术病理证实的前列腺硝患哲的常规MRI、弥敞加权成像（DWI）及动态增强扫描（DCE）图像,分析前列腺癌及邻近受累结构的图像特点。结果j5例前列腺癌．48例位于外脚带．4例位于中央带．3例同时累及外周带和中央带。所有癌灶于DWI图呈高信号,ADC图呈低信号,前列腺癌ADC值约（0．98±0．15）×10^-3m㎡/s。DCE譬期癌灶信号强度增高,其中41例呈速升速降型．5例呈速升平台型,9例呈速升缓降型。前列腺癌邻近受侵结构：腺周脂肪受侵8例,精囊受侵6例．神经血管束受侵4例．膀胱受侵6例,直肠受侵2例,箍腔淋巴结转移13例．骨转移并5例。结论MRI埘前列腺癌及邻近结构的诊断媳有重婴的诊断价值．为临i床治疗方案的选择具有重要指导意义。     

Dynamic MR defecography with an open-configuration, low-field, tilting MR system in patients with pelvic floor disorders

Purpose

This study was undertaken to explore the capabilities of an open-configuration, low-field, tilting, magnetic resonance (MR) system for investigating pelvic floor disorders and to compare the results obtained with the patient in the semiorthostatic and supine positions.

Materials and methods

Eighteen female patients with a diagnosis of pelvic floor disorder (physical examination and conventional defecography) underwent dynamic MR defecography (MRD) with a 0.25-T tilting MR system (G-scan, Esaote). Images were obtained after administration of contrast agent into the rectum, bladder and vagina in both the orthostatic and supine positions. Three-dimensional T2-weighted hybrid contrast-enhanced (HYCE) sequences and dynamic T1-weighted gradient echo (GE) sequences were acquired at rest, during maximal contraction of the anal sphincter, straining and defecation.

Results

Good image quality was obtained in 15/18 patients; three presented severe artefacts due to motion, and three had incontinence, which hampered the functional studies. Better anatomical detail was obtained with MRD compared with conventional defecography. Three prolapses were observed in the semiorthostatic position only, and seven were found to be more severe in the orthostatic than in the supine position.

Conclusions

Dynamic MRD with an open-configuration, low-field, tilting MR system is a feasible and promising tool for studying the pelvic floor. Larger series are necessary to assess its real diagnostic value.     

18F-FDG PET/CT delayed images after diuretic for restaging invasive bladder cancer.

PET with (18)F-FDG has been considered of limited value for detection of bladder cancer because of the urinary excretion of the tracer. The purpose of this study was to investigate the role of PET/CT in the detection and restaging of bladder cancer using furosemide and oral hydration to remove the excreted (18)F-FDG from the bladder. METHODS: Seventeen patients with bladder cancer (11 without cystectomy, 6 with total cystectomy and urinary diversion) underwent (18)F-FDG PET/CT from head to the upper thighs 60 min after the intravenous injection of 370 MBq of (18)F-FDG. Additional pelvic images were acquired 1 h after the intravenous injection of furosemide and oral hydration. PET/CT findings were confirmed by MRI, cystoscopy, or biopsy. RESULTS: PET/CT was able to detect bladder lesions in 6 of 11 patients who had not undergone cystectomy. These images changed the PET/CT final reading in 7 patients: Recurrent bladder lesions were detected in 6 patients, pelvic lymph node metastases in 2 patients, and prostate metastasis in 1. This technique overcame the difficulties posed by the urinary excretion of (18)F-FDG. Hypermetabolic lesions could be easily detected by PET and precisely localized in the bladder wall, pelvic lymph nodes, or prostate by CT. Seven of 17 patients (41%) were upstaged only after delayed pelvic images. CONCLUSION: Detection of locally recurrent or residual bladder tumors can be dramatically improved using (18)F-FDG PET/CT with delayed images after a diuretic and oral hydration.