CT Urography: An Update in Imaging Technique

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• 作者：Keynes Tze-Anns-Low ; Hui Seong Teh
• 关键词：CT urography ; Split ; bolus ; Dual ; energy CT ; Urinary stone characterization ; Virtual unenhanced ; Virtual non ; contrast
• 刊名：Current Radiology Reports
• 出版年：2015
• 出版时间：August 2015
• 年：2015
• 卷：3
• 期：8
• 全文大小：2,094 KB
• 参考文献：Recently published papers of particular interest have been highlighted as: -Of importance1.Smith RC, Rosenfield AT, Choe KA, et al. Acute flank pain: comparison of non-contrast-enhanced CT and intravenous urography. Radiology. 1995;194:789-4. doi:10.-148/?radiology.-94.-.-862980 .PubMed View Article
  2.Sommer FG, Jeffrey RB, Rubin GD, et al. Detection of ureteral calculi in patients with suspected renal colic: value of reformatted noncontrast helical CT. AJR Am J Roentgenol. 1995;165:509-3. doi:10.-214/?ajr.-65.-.-645461 .PubMed View Article
  3.Smith RC, Verga M, McCarthy S, Rosenfield AT. Diagnosis of acute flank pain: value of unenhanced helical CT. AJR Am J Roentgenol. 1996;166:97-01. doi:10.-214/?AJR.-6.-263 .PubMed View Article
  4.Katz DS, Lane MJ, Sommer FG. Unenhanced helical CT of ureteral stones: incidence of associated urinary tract findings. AJR Am J Roentgenol. 1996;166:1319-2.PubMed View Article
  5.Kim BS, Hwang IK, Choi YW, et al. Low-dose and standard-dose unenhanced helical computed tomography for the assessment of acute renal colic: prospective comparative study. Acta Radiol. 2005;46:756-3. doi:10.-080/-284185050021600- .PubMed View Article
  6.Poletti PA, Platon A, Rutschmann OT, Schmidlin FR, Iselin CE, Becker CD. Low-dose versus standard-dose CT protocol in patients with clinically suspected renal colic. AJR Am J Roentgenol. 2007;188:927-3. doi:10.-214/?AJR.-6.-793 .PubMed View Article
  7.Ahmed F, Zafar AM, Khan N, Haider Z, Ather MH. A paradigm shift in imaging for renal colic—is it time to say good bye to an old trusted friend? Int J Surg. 2010;8:252-. doi:10.-016/?j.?ijsu.-010.-2.-05 .PubMed View Article
  8.Molen AJ, Cowan NC, Mueller-Lisse UG, Nolte-Ernsting CCA, Takahashi S, Cohan RH. CT urography: definition, indications and techniques. A guideline for clinical practice. Eur Radiol. 2008;18:4-7. doi:10.-007/?s00330-007-0792-x .View Article
  9.Cohan RH, Sherman LS, Korobkin M, Bass JC, Francis IR. Renal masses: assessment of corticomedullary-phase and nephrographic-phase CT scans. Radiology. 1995;196:445-1.PubMed View Article
  10.Szolar DH, Kammerhuber F, Altziebler S, et al. Multiphasic helical CT of the kidney: increased conspicuity for detection and characterization of small (<?3-cm) renal masses. Radiology. 1997;202:211-.PubMed View Article
  11.Tsili AC, Efremidis SC, Kalef-Ezra J, et al. Multi-detector row CT urography on a 16-row CT scanner in the evaluation of urothelial tumors. Eur Radiol. 2007;17:1046-4. doi:10.-007/?s00330-006-0383-2 .PubMed View Article
  12.-Cowan NC. CT urography for hematuria. Nat Rev Urol. 2012;9:218-6. doi:10.-038/?nrurol.-012.-2 . In this review article, the high diagnostic accuracy of CT urography for urothelial cell carcinoma is highlighted. In patients with hematuria and at high-risk for urothelial cell carcinoma, CT urography is recommended as the initial imaging investigation and as a triage test for cystoscopy. This allows earlier diagnosis and better prognosis.
  13.Graser A, Johnson TRC, Chandarana H, Macari M. Dual energy CT: preliminary observations and potential clinical applications in the abdomen. Eur Radiol. 2009;19:13-3. doi:10.-007/?s00330-008-1122-7 .PubMed View Article
  14.-Takeuchi M, Kawai T, Ito M, et al. Split-bolus CT-urography using dual-energy CT: Feasibility, image quality and dose reduction. Eur J Radiol. 2012;81:3160-. doi:10.-016/?j.?ejrad.-012.-5.-05 . This prospective study of 30 patients with either haematuria or diagnosis of urothelial cancer (confirmed or suspected) showed that dual-energy split-bolus CT urography is technically feasible. Quality of dual-energy combined nephrographic-excretory phase images was found to be satisfactory. Omission of true non-enhanced images can reduce total radiation dose by 52?%, but quality of virtual non-enhanced images is not optimal and true non-enhanced images are still required when urine attenuation values need to be measured.
  15.-Karlo CA, Gnannt R, Winklehner A, et al. Split-bolus dual-energy CT urography: Protocol optimization and diagnostic performance for the detection of urinary stones. Abdom Imaging. 2013;38:1136-3. doi:10.-007/?s00261-013-9992-9 . This prospective study of 100 patients with urinary stones (as seen on true non-enhanced images) showed that split-bolus dual-energy CT urography was technically feasible, with better quality of virtual non-enhanced images (lower image noise and improved iodine subtraction) on 100/140 kVp setting compared to 80/140 kVp setting, both settings utilising tin filtration. On virtual non-enhanced images, 17?% of stones were missed and these missed stones were statistically significantly smaller than stones correctly found. The authors concluded that on virtual non-enhanced images, detection of urinary stones?<4?mm was limited.
  16.Kekelidze M, Dwarkasing RS, Dijkshoorn ML, et al. Kidney and urinary tract imaging: triple-bolus multide
• 作者单位：Keynes Tze-Anns-Low (1)
  Hui Seong Teh (2)
  
  1. Department of Diagnostic Radiology, Khoo Teck Puat Hospital, Singapore, Singapore
  2. Ng Teng Fong General Hospital, Singapore, Singapore
  
• 刊物主题：Imaging / Radiology;
• 出版者：Springer US
• ISSN：2167-4825

文摘

For decades, traditional IVU studies have been the mainstay in the investigation of urinary tract calculi and obstruction. However, they have been largely superseded by non-contrast CT in the present day. The use of contrast material further expands the utility of CT in the evaluation of urinary tract disease, allowing detection and characterization of renal masses and urothelial lesions. In this review article, we discuss the development and current role of CT urography as the complete imaging investigation in the genitourinary system. Conventional multiphasic protocols and split-bolus techniques for radiation dose reduction are considered. We then focus on how recent technological advances have allowed dual-energy CT to play a complementary role in CT evaluation of the genitourinary system, allowing stone and renal mass characterization, as well as creation of virtual unenhanced datasets. The use of associated post-processing software applications in the clinical context is illustrated.