Jia-Hwia Wang

Prospective Comparison of Unenhanced Spiral Computed Tomography and Intravenous Urography in the Evaluation of Acute Renal Colic

Background: The purpose of this prospective study was to evaluate the feasibility of replacing intravenous urography (IVU) with unenhanced computed tomography (CT) as the first line diagnostic modality for acute renal colic in the emergency department. Methods: In the 1‐year study period, 82 patients who presented themselves to the emergency room with acute renal colic and who were suspected to have ureteral stones were included. They received both IVU and unenhanced CT on the same day. Results: Sixty‐six patients were proven to have ureteral stone. Four had other urologic pathology (acute pyelonephritis, angiomyolipoma with hemorrhage, ureteropelvic junction stenosis). The remaining 12 had no definite urologic problem. Among the 66 patients with ureteral stone, the sensitivity for detecting ureteral stone was 98.5% for unenhanced CT and 59.1% for IVU. Correct diagnosis could be obtained in most of the patients receiving unenhanced CT, while IVU could provide only limited information about the intra‐abdominal pathology other than urologic system, and as many as 31.7% of the patients needed further imaging examination (sonography, CT, magnetic resonance imaging). In 5 patients, the relationship of the calcified spot and ureter were unclear on axial images. With curved multiplanar reformatted reconstruction, the diagnosis of ureter stone could be confidently made. No side effect (renal toxicity, allergic reaction) from intravenous administration of iodine‐containing contrast medium should be taken into consideration in CT. Besides, the average examination time was 108 minutes for IVU, which was significantly more than the 30 minutes for CT, including the time for curved multiplanar reformatted reconstruction. Conclusion: We consider that unenhanced CT is more effective and efficient than IVU and should replace IVU as the first‐line diagnostic tool for ureteral stone in the emergency department.

Evaluation of the extent of ketamine-induced uropathy: the role of CT urography

Background With growing ketamine abuse, ketamine-induced uropathy (KIU) has become more prevalent in recent years. This research evaluates the presence, distribution and extent of KIU in the upper and lower urinary tracts by retrospectively reviewing CT urography (CTU) images. Methods Patients diagnosed with KIU who underwent CT scanning from 1 January 2006 to 31 December 2011 were recruited. The CT protocols included three-phase CTU in six patients, split-bolus CTU in 17, two-phase CT in one and unenhanced CT in three. The CT images were retrospectively reviewed by two radiologists. Results A total of 27 patients participated in this study. The common CT findings included diffuse bladder wall thickening (88.9%), small bladder volume (66.7%) and perivesical inflammation (44.4%). Twelve patients (44.4%) were diagnosed with hydronephrosis, including three patients with unilateral hydronephrosis and nine with bilateral hydronephrosis. Of these patients, nine had ureteral wall thickening (33.3%) and two (7.4%) had ureterovesical junction involvement (ie, they had hydronephrosis but no ureteral wall thickening). One patient had a ureteral obstruction because of a ureter stone. The correlation between upper urinary tract involvement and grading of the interstitial cystitis was statistically non-significant (p=0.33). Four patients (14.8%) had a vesicovaginal fistula which could be detected in the excretory phase only. Conclusions Upper urinary tract involvement is common in patients with KIU. CTU might aid evaluation of the extent of KIU and prompt adequate management.

MR staging of clinical stage I and IIa cervical carcinoma: a reappraisal of efficacy and pitfalls

The purpose of this study was to evaluate the diagnostic efficacy and pitfalls of magnetic resonance (MR) imaging in preoperative staging of cervical cancer. MR imaging was performed to determine the tumor staging for 31 patients with cervical carcinoma emphasizing tumor size, parametrial invasion, vaginal invasion and lymph node metastases. Tumor size was 3.23+/-1.75 cm (mean+/-standard deviation) at MR imaging compared with 2.79+/-1.76 cm at surgical-pathologic evaluation. The discrepancy between the tumor size determined by MR imaging and the measured surgical specimens was consistent in tumors larger than 1 cm. In assessing parametrial invasion, vaginal invasion and lymph node metastases, MR imaging had an accuracy of 96.7 and 87%. In determining stage of disease and differentiating operable (< or =stage IIA) from advanced disease (> or =stage IIB), MR imaging had an accuracy of 83.8 and 96.7%. Pitfalls leading to staging errors included difficulties in differentiating cancer foci from surrounding tissue edema and excluding vaginal invasion in the presence of large cervical cancer. In conclusion, MR imaging is accurate in the evaluation of parametrial invasion and useful in the differentiation of operable from advanced disease. The ability of MR imaging to exclude vaginal invasion in the presence of large cervical cancer and differentiate cancer foci from surrounding tissue edema is not as reliable.

Percutaneous Radiofrequency Ablation of Renal Cell Carcinoma

Background: Preliminary data regarding the use of percutaneous radiofrequency ablation (RFA) for the treatment of renal cell carcinoma (RCC) are encouraging, and show the technique to be associated with minimal morbidity. Thus, the current study was designed to evaluate the clinical applications, treatment efficacy, and complications of percutaneous RFA in RCC. Methods: From February 2003 to February 2004, 12 consecutive patients with histopathologically proven RCC underwent imaging‐guided percutaneous RFA. The mean age of the patients (8 men and 4 women) was 76 years (range, 56‐87 years), and mean tumor diameter was 3.7 cm (range, 2.2‐8.0 cm). The efficacy of RFA was evaluated with contrast‐enhanced, dynamic computed tomography (CT) performed 1 month after treatment, and then every 3 months. A Radionics device with an internally cooled electrode was used in 7 patients, and a radiofrequency interstitial tissue ablation (RITA) device with an expandable needle electrode was used in 5. Complete necrosis was defined as a lack of contrast enhancement in the treated region on follow‐up CT studies. Results: Overall, 16 sessions of RFA were performed for 12 solitary renal tumors in 12 patients: 8 patients underwent a single RFA session, whereas 4 had 2 sessions. Dynamic CT after RFA showed complete necrosis in 9 of 12 tumors. In 3 patients with tumors of 4.5‐8.0 cm in diameter, enhancement of residual tissue was observed after RFA treatment, thus indicating residual tumor. Complete tumor necrosis was seen in all 5 tumors (100%) of diameter = 3.0 cm; 3 of 4 tumors (75%) of diameter 3.1‐5.0 cm; and 1 of 3 tumors (33%) of diameter > 5.0 cm. A big subcapsular hematoma, which was found in 1 patient after RFA, resolved completely within 10 months without treatment; no serious complications occurred in the other 11 patients. Conclusion: Percutaneous RFA is effective in the treatment of RCC. It is most successful for tumors not larger than 3 cm in diameter, and has a satisfactory success rate in tumors of 3‐5 cm in diameter. The rate of serious complications of RFA is low. Further studies are necessary to determine the long‐term efficacy of RFA in RCC.

Coincidental Angiomyolipoma and Renal Cell Carcinoma—Report of 1 Case and Review of Literature

A patient underwent simple enucleation for a suspected angiomyolipoma in the right kidney and histopathology revealed a mixture of renal cell carcinoma with angiomyolipoma. To our knowledge only 1 other case of a combination of a renomedullary tumor has been reported previously.

Parallel second stent placement for refractory ureteral stent malfunction in malignant ureteral obstruction.

PURPOSEnTo review retrospectively the outcome of placement of a parallel second ureteral stent in patients with urinary obstruction secondary to a malignancy.nnnMATERIALS AND METHODSnDuring the period 2005-2008, the medical records of patients with ureteral obstruction from an abdominal malignancy were reviewed. Patients who experienced malfunction of the first ureteral stent subsequently underwent either initial stent exchange (control group) or a parallel second ureteral stent placement. The outcomes of both groups were evaluated in terms of stent function at 1 week, 1 month, and 3 months after the procedure. Several clinical and imaging parameters were also compared between the two groups.nnnRESULTSnThe stent malfunction rate increased more rapidly in the control group. In 1 week, the malfunction rate was 29.4% in the parallel ureteral stent group and 56.7% in the control group. By the end of the third month, the malfunction rate was 72.7% in the parallel ureteral stent group and 100% in the control group. The creatinine level after the procedure was significantly lower in the parallel ureteral stent group (P = 0.004). The incidence of symptomatic urinary tract infection (UTI) was around 30% in both groups (P = 1.000).nnnCONCLUSIONSnParallel second ureteral stent placement has a high technical success rate. For terminally ill patients who have a malignancy and an occluded ureteral stent, the technique can effectively relieve obstruction and prolong the function of the stent.

Bowel Preparation of Outpatients for Intravenous Urography: Efficacy of Castor Oil Versus Bisacodyl

The purpose of this study was to compare the efficacy of two laxatives, castor oil and bisacodyl, in the routine bowel preparation of outpatients for intravenous urography (IVU). We used castor oil in patients undergoing IVU for 1 month, and then used bisacodyl in patients undergoing IVU for another month. Two uroradiologists, unaware of the method of bowel preparation, reviewed the standard radiographs and graded the residue in the large bowel and the clearness of the opacified urinary collecting system. In total, 71 consecutive outpatients received castor oil, and 84 received bisacodyl. For the castor oil group, grades from the two uroradiologists did not differ in terms of fecal residue on plain abdominal images (p = 0.54), and visualization of the urinary system on the left (p = 0.36) and right sides (p = 0.63). Findings were similar for bisacodyl recipients (p = 0.11, 0.59, and 0.32, respectively). When the laxative effect of the two agents was compared, we found no difference in the grading of fecal residue on plain abdominal images (p = 0.14), or in visualization of the urinary system on the left (p = 0.31) and right sides (p = 0.98). In conclusion, we observed no difference in laxative efficacy between castor oil and bisacodyl; thus, bisacodyl may be a useful alternative for bowel preparation before IVU.

Diagnostic Value of Unenhanced Computerized Tomography Urography in the Evaluation of Acute Renal Colic

This study prospectively evaluated the diagnostic value of unenhanced computerized tomography (CT) urography in patients with acute renal colic. Fifty‐nine patients with clinical manifestations of acute renal colic underwent unenhanced helical CT to evaluate urinary tract abnormalities. Reformatted three‐dimensional CT urography was performed in all patients. The findings were correlated with ureteroscopy, surgical findings, histopathologic findings, and clinical course. CT urography detected urinary abnormalities in 57 of 59 patients with the clinical manifestation of acute renal colic, including 45 cases of urolithiasis, three urinary malignancies, one congenital abnormality, and eight ureteral strictures (due to chronic inflammation or fibrosis). CT urography showed negative findings in the urinary system in two patients, and after clinical follow‐up, urinary abnormality was excluded in these patients. Incidental findings of extrarenal disease were noted in six patients (pulmonary abnormalities, n = 2; gallstones, n = 4). Only one patient with urolithiasis was misdiagnosed as having a renal tumor by CT urography. The sensitivity and specificity of CT urography in diagnosing urolithiasis was 97.8% (44/45) and 100% (14/14), respectively. Three‐dimensional CT urography is a newly developed modality to evaluate anomalies of the urinary tract. The highly accurate diagnostic value of CT urography makes it a suitable alternative or substitutive modality in patients with acute flank pain.

Unusual Presentation of Urothelial Carcinoma of the Bladder With Noncontiguous Rectal and Diffuse Muscular Skeletal Metastases

AN 83-year-old man presented with frequent bowel movements and weight loss in the last 6 months. History was remarkable for hypertension and diabetes mellitus. Digital rectal examination revealed a tumor 3 cm from the anal verge, which was subsequently confirmed by rectoscopy. Biopsy revealed poorly differentiated carcinoma. The tumor cells stained strongly positive for CK7, weakly positive for CK20, and negative for CDX-2 and S-100. Therefore, primary adenocarcinoma of the colon was less likely and tumor growth of urothelial origin was suspected. Subsequent computerized tomography (CT) of the abdomen showed thickening of the right posterior wall of the bladder and noncontiguous circumferential thickening of the rectal wall (figs. 1 and 2). CT also revealed extensively infiltrative, strong enhancing lesions in multiple skeletal muscles, including bilateral psoas major, quadratus lumborum, iliacus, gluteus medius/minimus, obturator externus, quadratus femoris and adductor brevis/magnus. Cystoscopic biopsy of the bladder tumor confirmed high grade urothelial carcinoma. Ultrasound biopsy was performed for the skeletal muscle lesion and the result was consistent with metastatic urothelial carcinoma. The patient was treated with chemotherapy. Bladder urothelial carcinoma often metastasizes to regional lymph nodes, liver, lung and bone. The lower gastrointestinal tract is usually involved by direct tumor invasion. Noncontiguous rectal metastasis from urothelial carcinoma presenting as an annular rectal tumor is rare. 1 This case had concomitant diffuse skeletal muscle metastasis, which is an even rarer presentation of urothelial carcinoma. 2 Metastatic muscular lesions of urothelial carcinoma origin usually show low density and ring enhancement on CT. 3 However, in

Intraperitoneal Rupture of the Bladder

Computed tomographic cystography is an accurate method for diagnosis of bladder rupture. Sagittal and coronal reformation may be helpful in identifying most sites of bladder rupture. Intraperitoneal bladder rupture must undergo formal repair and suprapubic tube drainage.