Transitional cell carcinoma of the upper urinary tract: optimizing image interpretation with 3D reconstructions. ACTA ACUST UNITED AC. 2012;37:1129-1140. [PMID: 22207253 DOI: 10.1007/s00261-011-9838-2]

The application of cinematic rendering to CT evaluation of upper tract urothelial tumors: principles and practice

Upper tract urothelial carcinoma (UTUC) is a relatively uncommon but aggressive genitourinary malignancy for which multi-phase contrast-enhanced computed tomography (CT) plays an important role in evaluation and staging. 3D imaging with maximum intensity projection (MIP) and volume-rendered (VR) images has been described as a useful means of evaluating UTUC. In this study, we describe the technique of a novel 3D methodology known as cinematic rendering (CR) and provide clinical examples of UTUC visualized with CR. CR utilizes a complex universal lighting model in order to create photorealistic images with improved detail and depth in comparison to MIP or VR images. In the case of UTUC, CR can be used in different contrast phases to show abnormally thickened and enhancing urothelium or filling defects in the renal collecting system or ureters in the excretory phase. CR images can also be manipulated in order to generate translucent views of the upper urinary tract in order to add conspicuity to intraluminal findings.

Upper urinary tract urothelial carcinoma on multidetector CT: spectrum of disease

Urothelial carcinoma of the upper urinary tract (UUT) is a relatively uncommon genitourinary malignancy, accounting for about 5-7% of urothelial tumors. The significant features of this tumor are multifocality and high rate of recurrence. Computed tomography urography (CTU) has replaced excretory urography (EU) and retrograde pyelography (RP) for imaging of upper tract urothelial carcinoma. While many studies have confirmed high sensitivity (88-100%) and specificity (93-100%) of CTU, an optimized CT protocol is of critical importance in screening, staging, and post-operative follow-up of patients (Chlapoutakis, Eur J Radiol 73(2):334-338, 2010; Caoli and Cohan, Abdom Radiol (NY) 41(6):1100-1107, 2016). The key element of the CT protocol is to have adequate distension of the collecting system with excreted contrast, to detect subtle lesions at an early stage. In this article, we discuss the background of upper urinary tract TTC, pathogenesis, CT protocol and the role of imaging in evaluation of this malignancy, staging, as well as different imaging appearances.

3D CT of renal pathology: initial experience with cinematic rendering

3D computed tomography (CT) visualizations of volumetric data have become an important aspect of diagnostic imaging. The utility of 3D CT has been well described for the imaging of a number of renal pathologies. Recently, a new 3D visualization technique known as cinematic rendering (CR) has become available and provides photorealistic images derived from standard CT acquisitions by use of a complex global lighting model. Herein, we describe a number of normal variant and pathologic conditions of the kidney visualized with CR. We provide comparisons of findings with CR to traditional methods of 3D imaging and comment on the potential applications of this new method of 3D CT rendering.

Diagnostic Value Comparison of Urothelium Carcinoma Among Urine Exfoliated Cells Fluorescent In Situ Hybridization (FISH) Examination, Computerized Tomography (CT) Scan, and Urine Cytologic Examination

BACKGROUND This study aimed to compare the clinical effectiveness of urine exfoliated cells FISH examination, CT scan, and urine cytologic examination on the diagnosis of upper urinary tract urothelium carcinoma with hematuresis symptom. MATERIAL AND METHODS A total of 30 patients with suspicious upper urinary tract urothelium carcinoma between Aug 2010 and Aug 2011 were enrolled, including 23 males and 7 females. All the subjects received urine exfoliated cells FISH examination, CT scan, and urine cytologic examination. Twenty-one cases were diagnosed as urothelium carcinoma, including 14 cases of carcinoma of renal pelvis and 7 cases of carcinoma of ureter. There were 6 cases in stage Ta/T1, 12 cases in stage T2, and 3 cases in T3/T4. The other 9 cases consisted of 1 case of neuroendocrine carcinoma of the renal pelvis, 2 cases of nephrotuberculosis, and 6 cases of renal clear cell carcinoma. RESULTS The total sensitivity of FISH examination, CT scan, and urine cytologic examination on upper urinary tract urothelium carcinoma was 85.7%, 66.7%, and 28.6%, respectively (P<0.05). The tumor staging detection on Ta/T1, T2, and T3/T4 by FISH was 66.7%, 91.7%, 100%; by CT scan 33.3%, 75.0%, 100%; and by urine cytologic examination 0%, 25.0%, and 100%. Their diagnostic specificities were 88.9%, 77.8%, and 100%, respectively (P<0.05). CONCLUSIONS The diagnostic sensitivity on upper urinary tract urothelium carcinoma was highest in FISH examination, followed by CT scan and urine cytologic examination. FISH technique obviously improves the diagnosis of upper urinary tract urothelium carcinoma.

Upper and Lower Tract Urothelial Imaging Using Computed Tomography Urography

Computed tomography (CT) urography is the best noninvasive method of evaluating the upper urinary tract for urothelial malignancies. However, the utility of CT urography is heavily contingent on the use of proper image acquisition protocols. This article focuses on the appropriate protocols for optimizing CT urography acquisitions, including contrast administration and the timing of imaging acquisitions, as well as the use of ancillary techniques to increase collecting system distention. In addition, imaging findings are discussed that should raise concern for urothelial carcinoma at each of the 3 segments of the urinary tract: the intrarenal collecting systems, ureters, and bladder.

Evolution of imaging in rectal cancer: multimodality imaging with MDCT, MRI, and PET

Magnetic resonance imaging (MRI), multidetector computed tomography (MDCT), and positron emission tomography (PET) are complementary imaging modalities in the preoperative staging of patients with rectal cancer, and each offers their own individual strengths and weaknesses. MRI is the best available radiologic modality for the local staging of rectal cancers, and can play an important role in accurately distinguishing which patients should receive preoperative chemoradiation prior to total mesorectal excision. Alternatively, both MDCT and PET are considered primary modalities when performing preoperative distant staging, but are limited in their ability to locally stage rectal malignancies. This review details the role of each of these three modalities in rectal cancer staging, and how the three imaging modalities can be used in conjunction.

[Oncological diseases and postoperative alterations of the bladder and urinary tract]

In the challenging evaluation of upper urinary tract malignancies multidetector computed tomography (CT) has become the standard imaging method. Cross sectional imaging not only allows the detection and visualization of the tumor itself but also provides nodal and metastasis staging in one examination (one-stop-shop). The majority of urothelial carcinomas are located in the urinary bladder. In this case, CT and more recently magnetic resonance imaging (MRI) can also deliver decisive information regarding TNM classification. A combination of clinical, histological, morphological and functional parameters allows both risk stratification and a targeted therapy based on the individual tumor stage.

MDCT evaluation of ureteral tumors: advantages of 3D reconstruction and volume visualization

OBJECTIVE

This article reviews the use of CT urography in diagnosing ureteral transitional cell carcinomas, different CT urography protocols, CT findings suggestive of ureteral malignancy, and the importance of 3D reconstructions.

CONCLUSION

The ureters can be problematic to evaluate on CT, partly because of difficulties in obtaining adequate ureteral distention and opacification. Proper diagnosis hinges not only on appropriate interpretation of the axial images but also on the utilization of a 3D technique (volume rendering or maximum intensity projection) as an ancillary tool.

Computed tomography of Crohn’s disease: The role of three dimensional technique

Crohn’s disease, a transmural inflammatory bowel disease, remains a difficult entity to diagnose clinically. Over the last decade, multidetector computed tomography (CT) has become the method of choice for non-invasive evaluation of the small bowel, and has proved to be of significant value in the diagnosis of Crohn’s disease. Advancements in CT enterography protocol design, three dimensional (3-D) post-processing software, and CT scanner technology have allowed increasing accuracy in diagnosis, and the acquisition of studies at a much lower radiation dose. The cases in this review will illustrate that the use of 3-D technique, proper enterography protocol design, and a detailed understanding of the different manifestations of Crohn’s disease are all critical in properly diagnosing the full range of possible complications in Crohn’s patients. In particular, CT enterography has proven to be effective in identifying involvement of the small and large bowel (including active inflammation, stigmata of chronic inflammation, and Crohn’s-related bowel neoplasia) by Crohn’s disease, as well as the extra-enteric manifestations of the disease, including fistulae, sinus tracts, abscesses, and urologic/hepatobiliary/osseous complications. Moreover, the proper use of 3-D technique (including volume rendering and maximum intensity projection) as a routine component of enterography interpretation can play a vital role in improving diagnostic accuracy.