The efficacy of ultrasonography for the detection of upper tract urothelial carcinoma

PURPOSE

Ultrasonography and computed tomography urography are two commonly used modalities to image the upper tracts for the evaluation of hematuria. This study evaluated the efficacy of ultrasonography for the detection of upper tract urothelial carcinoma compared to computed tomography urography as a standard reference.

METHODS

This retrospective study included patients with urothelial carcinoma of the renal pelvis and/or ureter who were diagnosed using computed tomography urography and underwent surgical treatment. We calculated the sensitivity of ultrasonography in upper tract urothelial carcinoma diagnosis, further classified the degree of hydronephrosis on ultrasonography, and analyzed the relationship between the sensitivity and the degree of hydronephrosis and tumor location. Additionally, the usefulness of the combination of the screening ultrasonography findings, the presence of gross hematuria, and/or urine cytology was analyzed.

RESULTS

This study included 136 patients with upper urothelial carcinoma. Ultrasonography in the diagnosis had 45.6% sensitivity, and ultrasonography findings, including the detection of hydronephrosis, were present in 72.8%. The presence of hydronephrosis and tumor location were associated with detection by ultrasonography. The tumor was identified in a total of 134 (98.5%) patients by combining tumor detection and hydronephrosis using ultrasonography with gross hematuria and positive urine cytology as screening.

CONCLUSION

Ultrasonography showed acceptable sensitivity for upper tract urothelial carcinoma diagnosis. Considering the hydronephrosis findings, ultrasonography is a useful screening tool for upper tract urothelial carcinoma. Additionally, excessive computed tomography examinations can be reduced by adding gross hematuria and positive urine cytology.

Side-by-side evaluation of virtual non-contrast and post-contrast images improves detection of clinically significant urolithiasis on single-phase split bolus dual-energy CT urography

OBJECTIVES

Studies show insufficient sensitivity of virtual non-contrast (VNC) reconstructions for stone detection in dual-energy CT urography (DE-CTU). The aim of this study was to investigate if side-by-side-evaluation of both VNC and post-contrast images could increase the sensitivity of single-phase split bolus DE-CTU.

METHODS

Consecutive patients with haematuria who underwent split bolus DE-CTU on the same dual-source DE-CT scanner were retrospectively enrolled in the study. Intravenous furosemide and oral hydration were employed. Two readers, independently and then jointly in two separate sessions, recorded the location and the longest axial stone diameter on three randomised sets of images: separate VNC and post-contrast images, and side-by-side-reconstructions. True non-contrast (TNC) images served as the standard of reference.

RESULTS

A total of 83 urinary stones were detected on TNC images. Independent reader side-by-side-evaluation of VNC and post-contrast images yielded higher stone detection sensitivity (76 and 84%, respectively) compared to evaluation of only VNC (71 and 81%, respectively) or post-contrast images (64 and 80%, respectively). The sensitivity of joint reader evaluation of side-by-side-images reached almost 86% and was not significantly different from TNC images (p = 0.77). All stones larger than 3 mm were correctly detected by side-by-side-evaluation. Dose reduction of 55% could be achieved by omitting TNC scans.

CONCLUSION

Side-by-side-VNC and post-contrast image evaluation enable detection of clinically significant urolithiasis on single-phase split bolus DE-CTU with significant dose reduction.

ADVANCES IN KNOWLEDGE

This study shows that single-phase DE-CTU is feasible if VNC imaging is simultaneously utilised with post-contrast images.

Accuracy of ultrasound vs computed tomography scan for upper urinary tract malignancies and development of a risk-based diagnostic algorithm for haematuria in a UK tertiary centre

PURPOSE

There is no consensus across guidelines on a diagnostic algorithm for upper urinary tract (UUT) evaluation following presentation with haematuria. Our aim is to compare the diagnostic accuracy of ultrasound (USS) compared to CT-scan for UUT malignancies and also determine the considerations important for a risk-based diagnostic protocol for haematuria.

METHODS

We reviewed our 'haematuria clinic' database to identify patients who had both USS and CT-scan for UUT evaluation between September 2015 and August 2017, and calculated the diagnostic accuracy of these imaging modalities for histologically confirmed UUT cancers. Furthermore, we identified risk factors in our diagnostic algorithm for haematuria and conducted regression analysis to determine their ability to predict UUT malignancies.

RESULTS

Overall, 575 patient records were studied. Age range was 21-92 years, M:F was 1.4:1, majority (81.2%) had visible haematuria, and 12 (2.1%) UUT cancers were diagnosed [renal cell carcinoma-1.4%; upper tract urothelial cancer-0.7%]. USS and CT-scan had diagnostic accuracy for UUT cancers of 95.8 and 99.1%, respectively (p < 0.001). Haematuria type was a significant consideration only on univariate analysis, while multivariate binary logistic regression showed that male gender, smoking, occupational exposure, and positive urologic history were the main risk factors associated with UUT malignancies.

CONCLUSION

USS and CT-scan have comparably high diagnostic accuracy for detecting UUT malignancies. USS may, therefore, be considered as the first-line UUT imaging modality when utilized in a risk-based diagnostic algorithm. Larger, multicentred studies are needed to validate our findings and influence guideline development.

Split bolus dual-energy CT urography after urine dilution: a one-stop shop for detection and characterisation of urolithiasis

AIM

To determine the diagnostic performance of split-bolus dual-energy computed tomography (CT) urography (SBDECTU) in the detection and characterisation of urolithiasis.

MATERIALS AND METHODS

This single-centre Institute Ethics Committee (IEC)-approved prospective study was conducted from April 2014 to November 2015. One hundred and thirty consenting adults with microscopic haematuria underwent dual-energy true non-enhanced CT (DETNE) of the whole abdomen followed by a SBDECTU. The SBDECTU protocol consisted of synchronous nephrogram-urogram acquisition following urine dilution by oral hydration and normal saline injection. Calculi were detected and characterised using virtual non-enhanced (VNE) images derived from SBDECT were compared with DETNE (the reference standard). The subjective image quality and radiation dose were compared.

RESULTS

Twenty-six participants had one or more calculi (total 129 calculi) detected on DETNE CT. The sensitivity and specificity of VNE on a per-patient basis were 100%. Of the 129 calculi, 118 were detected on VNE, with a sensitivity of 91.47% and an accuracy of 91.47%. Of the calculi, 83.9% (99/118) could be characterised on SBDECTU images. On VNE images, complete iodine subtraction was seen in 73.1% (19/26). By omitting DETNE CT, the mean dose-length product of 537.6±152.9 mGy and volume CT dose index of 10.9±2.9 mGy•cm² could have been saved.

CONCLUSION

SBDECTU has high diagnostic accuracy in the detection and characterisation of clinically significant urinary calculi at potentially half the radiation dose.

Examining the upper urinary tract in patients with hematuria-time to revise the CT urography protocol?

BACKGROUND

Three-phase CT urography (CTU) is the gold standard for evaluating the upper urinary tract in patients with hematuria. We aimed to evaluate the accuracy of CTU for detecting upper urothelial cell carcinomas (UCC) in patients with hematuria and negative cystoscopy. Secondly, we aimed to determine the tumor visibility on each CTU phase.

MATERIAL AND METHODS

This retrospective study included all patients with hematuria referred to CTU after a negative cystoscopy during 2016 and 2017. The original CTU reports were dichotomized as negative or positive. All patient charts were reviewed after a minimum of 18-month follow-up in order to register missed cancers. The results of biopsies and clinical follow-up were used as the reference standard. Two reviewers retrospectively evaluated the tumor visibility of each CT sequence in all true-positive CTUs.

RESULTS

We included 376 patients with hematuria who underwent CTU after a negative cystoscopy. Macroscopic and microscopic hematuria occurred in 87% (327) and 13% (49), respectively. The incidence of upper urothelial cell carcinoma was 1.9% (7), and the sensitivity of CTU was 100% (95% CI, 59-100), specificity was 99% (95% CI, 98-100), positive predictive value was 88% (95% CI, 47-99), and negative predictive value was 100% (95% CI, 99-100). The accuracy was 99% (95% CI, 90-100). All UCCs were visible on the nephrographic phase for both reviewers.

CONCLUSION

CTU is highly accurate for detecting upper UCCs. All cases were seen on the nephrographic phase. This suggests that the CTU protocol can be simplified.

KEY POINTS

• CT urography is highly accurate for detecting upper urothelial cell carcinomas. • All cancers were seen on the nephrographic phase. • All cancers were detected in patients with macroscopic hematuria.

Evaluation of upper tract urothelial carcinomas by contrast-enhanced ultrasound

AIM

To describe the findings and behaviour of contrast-enhanced ultrasound in the study of upper tract urothelial tumours and to assess its usefulness for diagnosis.

MATERIAL AND METHODS

We reviewed our hospital's database over a period of 45 months to identify patients diagnosed with upper tract urothelial carcinomas. We reviewed the findings on mode B-ultrasound, contrast-enhanced ultrasound (location and qualitative assessment of intensity and washout of enhancement), and made a comparison with other techniques (computed tomography or magnetic resonance), and with the surgical specimen.

RESULTS

We found 42 patients with a diagnosis of upper tract urothelial carcinoma confirmed with surgery over the period reviewed. Twenty-eight (67%) patients underwent contrast-enhanced ultrasound. Baseline ultrasound showed hydronephrosis with or without ureteral dilatation with echogenic content occupying the renal calyx (6), pelvis (10) or ureter (12). After injection of contrast, enhancement was noticed in 100% of the lesions, with similar intensity to the cortex in 23, and less in 5. Twenty-four lesions showed early washout, before the cortex, between 40 and 55seconds after the injection. The diagnosis was correct in 27 cases. Localisation coincided with the histological specimen in 28 cases, and 3 patients had additional distal carcinoma foci.

CONCLUSION

Contrast-enhanced ultrasound is a useful technique for diagnosing upper tract urothelial tumours that increases confidence in the diagnosis.

68Ga PSMA-11 PET with CT urography protocol in the initial staging and biochemical relapse of prostate cancer

Background

⁶⁸Ga-labelled prostate specific membrane antigen (PSMA) ligand PET/CT is a promising modality in primary staging (PS) and biochemical relapse (BCR) of prostate cancer (PC). However, pelvic nodes or local recurrences can be difficult to differentiate from radioactive urine. CT urography (CT-U) is an established method, which allows assessment of urological malignancies. The study presents a novel protocol of ⁶⁸Ga-PSMA-11 PET/CT-U in PS and BCR of PC.

Methods

A retrospective review of PSMA PET/CT-U preformed on 57 consecutive patients with prostate cancer. Fifty mL of IV contrast was administered 10 min (range 8–15) before the CT component of a combined PET/CT study, acquired approximately 60 min (range 40–85) after administration of 166 MBq (range 91–246) of ⁶⁸Ga-PSMA-11. PET and PET/CT-U were reviewed by two nuclear medicine physicians and CT-U by a radiologist. First, PET images were reviewed independently followed by PET/CT-U images. Foci of activity which could not unequivocally be assessed as disease or urinary activity were recorded. PET/CT-U was considered of potential benefit in final interpretation when the equivocal focal activity in PET images corresponded to opacified ureter, bladder, prostate bed, seminal vesicles, or urethra. Student’s T test and Pearson’s correlation coefficient was used for assessment of variables including lymph node size and standardized uptake value.

Results

Overall 50 PSMA PET/CT-U studies were performed for BCR and 7 for PS. Median PSA with BCR and PS were 2.0 ± 11.4 ng/ml (0.06–57.3 ng/ml) and 18 ± 35.3 ng/ml (6.8–100 ng/ml), respectively. The median Gleason-score for both groups was 7 (range 6–10). In BCR group, PSMA PET was reported positive in 36 (72%) patients, CT-U in 11(22%) patients and PET/CT-U in 33 (66%) patients. In PS group, PSMA PET detected the primary site in all seven patients, of which one patient with metastatic nodal disease had negative CT finding. Of 40 equivocal foci (27/57 patients) on PET, 11 foci (10/57 patients, 17.5%) were localized to enhanced urine on PET/CT-U, hence considered of potential benefit in interpretation. Of those, 3 foci (3 patients) were solitary sites of activity on PSMA imaging including two local and one nodal site and 4 foci (3 patients) were in different nodal fields.

Conclusions

PET/CT-U protocol is a practical approach and may assist in interpretation of ⁶⁸Ga-PSMA-11 imaging by delineation of the contrast opacified genitourinary system and matching focal PSMA activity with urinary contrast.

Electronic supplementary material

The online version of this article (10.1186/s40644-017-0133-5) contains supplementary material, which is available to authorized users.

Clinical Guideline for Female Lower Urinary Tract Symptoms

The "Japanese Clinical Guideline for Female Lower Urinary Tract Symptoms," published in Japan in November 2013, contains two algorithms (a primary and a specialized treatment algorithm) that are novel worldwide as they cover female lower urinary tract symptoms other than urinary incontinence. For primary treatment, necessary types of evaluation include querying the patient regarding symptoms and medical history, examining physical findings, and performing urinalysis. The types of evaluations that should be performed for select cases include evaluation with symptom/quality of life (QOL) questionnaires, urination records, residual urine measurement, urine cytology, urine culture, serum creatinine measurement, and ultrasonography. If the main symptoms are voiding/post-voiding, specialized treatment should be considered because multiple conditions may be involved. When storage difficulties are the main symptoms, the patient should be assessed using the primary algorithm. When conditions such as overactive bladder or stress incontinence are diagnosed and treatment is administered, but sufficient improvement is not achieved, the specialized algorithm should be considered. In case of specialized treatment, physiological re-evaluation, urinary tract/pelvic imaging evaluation, and urodynamic testing are conducted for conditions such as refractory overactive bladder and stress incontinence. There are two causes of voiding/post-voiding symptoms: lower urinary tract obstruction and detrusor underactivity. Lower urinary tract obstruction caused by pelvic organ prolapse may be improved by surgery.

Haematuria in postrenal transplant patients

Haematuria has a prevalence of 12% in the postrenal transplant patient population. It heralds potentially dangerous causes which could threaten graft loss. It is important to consider causes in light of the unique, urological, and immunological standpoints of these patients. We review the literature on common causes of haematuria in postrenal transplant patients and suggest the salient approach to the evaluation of this condition. A major cause of haematuria is urinary tract infections. There should be a higher index of suspicion for mycobacterial, fungal, and viral infection in this group of immunosuppressed patients. Measures recommended in the prevention of urinary tract infections include early removal of foreign bodies as well as prophylactic antibiotics during the early transplant phase. Another common cause of haematuria is that of malignancies, in particular, renal cell carcinomas. When surgically managing cancer in the setting of a renal transplant, one has to be mindful of the limited retropubic space and the need to protect the anastomoses. Other causes include graft rejections, recurrences of primary disease, and calculus formation. It is important to perform a comprehensive evaluation with the aid of an experienced multidisciplinary transplant team.

Ultrasound Doppler renal resistive index: a useful tool for the management of the hypertensive patient

The Doppler-derived renal resistive index has been used for years in a variety of clinical settings such as the assessment of chronic renal allograft rejection, detection and management of renal artery stenosis, evaluation of progression risk in chronic kidney disease, differential diagnosis in acute and chronic obstructive renal disease, and more recently as a predictor of renal and global outcome in the critically ill patient. More recently, evidence has been accumulating showing that an increased renal resistive index not only reflects changes in intrarenal perfusion but is also related to systemic hemodynamics and the presence of subclinical atherosclerosis, and may thus provide useful prognostic information in patients with primary hypertension. On the basis of these results, the evaluation of renal resistive index has been proposed in the assessment and management of patients with primary hypertension to complement other signs of renal abnormalities.

Haematuria: an imaging guide

This paper discusses the current status of imaging in the investigation of patients with haematuria. The physician must rationalize imaging so that serious causes such as malignancy are promptly diagnosed while at the same time not exposing patients to unnecessary investigations. There is currently no universal agreement about the optimal imaging work up of haematuria. The choice of modality to image the urinary tract will depend on individual patient factors such as age, the presence of risk factors for malignancy, renal function, a history of calculus disease and pregnancy, and other factors, such as local policy and practice, cost effectiveness and availability of resources. The role of all modalities, including conventional radiography, intravenous urography/excretory urography, ultrasonography, retrograde pyelography, multidetector computed tomography urography (MDCTU), and magnetic resonance urography, is discussed. This paper highlights the pivotal role of MDCTU in the imaging of the patient with haematuria and discusses issues specific to this modality including protocol design, imaging of the urothelium, and radiation dose. Examination protocols should be tailored to the patient while all the while optimizing radiation dose.

Correlation between computerized tomography density measurements of urinary bladder and urinalysis results

Our aim was to investigate whether there is a correlation between computerized tomography (CT) density measurements of the urinary bladder and urinalysis results. Patients were subdivided into three groups with respect to urinalysis results: Group 1, no leukocytes or erythrocytes detected in urine (n=25); Group 2, erythrocytes detected in urine (n=50); and Group 3, leukocytes and erythrocytes detected in urine (n=98). In CT sections, densitometric measurements had been performed from three zones on each section and groups were compared in terms of densitometry results. Our results indicate that density measurements of CT views form the urinary bladder may provide valuable data on hematuria and leukocyturia.

Transitional cell carcinoma of the upper urinary tract: optimizing image interpretation with 3D reconstructions

PURPOSE

This article reviews the pathophysiology of transitional cell carcinoma (TCC), CT urography (CTU) protocols, different possible 3D reconstruction techniques, and the importance of 3D reconstructions for appropriate interpretation.

RESULTS/CONCLUSION

CTU has largely replaced conventional IV pyelography in the evaluation of the upper urinary tract for TCC. The majority of large lesions can be easily seen on standard axial images with multiplanar reformats. However, it is imperative to also use 3D reconstructions when interpreting these studies, as subtle lesions can be difficult to visualize on the more traditional images. In this pictorial essay, we present multiple cases of upper urinary tract TCC which illustrate the value of 3D reconstructions for increasing the conspicuity of lesions, particularly at the junction of the infundibulum and calyx and in the ureters. As these cases demonstrate, each of the three possible 3D reconstruction techniques (maximum intensity projection, volume rendering, and volume rendered "virtual ureteroscopy") has its own distinct advantages, although the pitfalls of each technique must also be kept in mind.

Accidental finding of bladder cancer in 99mTc methylene diphosphonate whole-body bone scan

A 53-year-old woman with a history of nasopharyngeal carcinoma underwent (99m)Tc methylene diphosphonate (MDP) whole-body scintigraphy for tumor staging. An MDP-avid lesion located in the urinary bladder was found. Computed tomography showed a protruding mass with calcific surface in the left inferolateral wall of the urinary bladder. A biopsy was conducted and the pathological report confirmed the diagnosis of transitional cell carcinoma. The patient received transurethral resection and Bacillus Calmette-Guérin intravesical therapy. Four months later, she underwent an (18)F-FDG PET/CT scan. Unfortunately, tumor recurrence in the bladder cancer was diagnosed by the (18)F-FDG PET/CT scan.

Evaluation of diagnostic strategies for bladder cancer using computed tomography (CT) urography, flexible cystoscopy and voided urine cytology: results for 778 patients from a hospital haematuria clinic

Study Type - Diagnostic (exploratory cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Haematuria clinics with same day imaging and flexible cystoscopy are an efficient way for investigating patients with haematuria. The principal role of haematuria clinics with reference to bladder cancer is to determine which patients are 'normal' and may be discharged, and which patients are abnormal and should undergo rigid cystoscopy. It is well recognised that CT urography offers a thorough evaluation of the upper urinary tract for stones, renal masses and urothelial neoplasms but the role of CT urography for diagnosing bladder cancer is less certain. The aim of the present study was to evaluate the diagnostic accuracy of CT urography in patients with visible haematuria aged >40 years and to determine if CT urography has a role for diagnosing bladder cancer. This study shows that the optimum diagnostic strategy for investigating patients with visible haematuria aged >40 years with infection excluded is a combined strategy using CT urography and flexible cystoscopy. Patients positive for bladder cancer on CT urography should be referred directly for rigid cystoscopy and so avoid flexible cystoscopy. The number of flexible cystoscopies required therefore may be reduced by 17%. The present study also shows that the diagnostic accuracy of voided urine cytology is too low to justify its continuing use in a haematuria clinic using CT urography and flexible cystoscopy.

OBJECTIVES

To evaluate and compare the diagnostic accuracy of computed tomography (CT) urography with flexible cystoscopy and voided urine cytology for diagnosing bladder cancer. To evaluate diagnostic strategies using CT urography as: (i) an additional test or (ii) a replacement test or (iii) a triage test for diagnosing bladder cancer in patients referred to a hospital haematuria rapid diagnosis clinic.

PATIENTS AND METHODS

The clinical cohort consisted of a consecutive series of 778 patients referred to a hospital haematuria rapid diagnosis clinic from 1 March 2004 to 17 December 2007. Criteria for referral were at least one episode of macroscopic haematuria, age >40 years and urinary tract infection excluded. Of the 778 patients, there were 747 with technically adequate CT urography and flexible cystoscopy examinations for analysis. On the same day, patients underwent examination by a clinical nurse specialist followed by voided urine cytology, CT urography and flexible cystoscopy. Voided urine cytology was scored using a 5-point system. CT urography was reported immediately by a uroradiologist and flexible cystoscopy performed by a urologist. Both examinations were scored using a 3-point system: 1, normal; 2, equivocal; and 3, positive for bladder cancer. The reference standard consisted of review of the hospital imaging and histopathology databases in December 2009 for all patients and reports from the medical notes for those referred for rigid cystoscopy. Follow-up was for 21-66 months.

RESULTS

The prevalence of bladder cancer in the clinical cohort was 20% (156/778). For the diagnostic strategy using CT urography as an additional test for diagnosing bladder cancer, when scores of 1 were classified as negative and scores of 2 and 3 as positive, sensitivity was 1.0 (95% confidence interval [CI] 0.98-1.00), specificity was 0.94 (95% CI 0.91-0.95), the positive predictive value (PPV) was 0.80 (95% CI 0.73-0.85) and the negative predictive value (NPV) was 1.0 (95% CI 0.99-1.00). For the diagnostic strategy using CT urography as a replacement test for flexible cystoscopy for diagnosing bladder cancer, when scores of 1 were classified as negative and scores of 2 and 3 as positive, sensitivity was 0.95 (95% CI 0.90-0.97), specificity was 0.83 (95% CI 0.80-0.86), the PPV was 0.58 (95% CI 0.52-0.64), and the NPV was 0.98 (95% CI 0.97-0.99). Similarly using flexible cystoscopy for diagnosing bladder cancer, if scores of 1 were classified as negative and scores of 2 and 3 as positive, sensitivity was 0.98 (95% CI 0.94- 0.99), specificity was 0.94 (95% CI 0.92-0.96), the PPV was 0.80 (95% CI 0.73-0.85) and the NPV was 0.99 (95% CI 0.99-1.0). For the diagnostic strategy using CT urography and flexible cystoscopy as a triage test for rigid cystoscopy and follow-up (option 1), patients with a positive CT urography score are referred directly for rigid cystoscopy, and patients with an equivocal or normal score were referred for flexible cystoscopy. Sensitivity was 1.0 (95% CI 0.98-1.0), specificity was 0.94 (95% CI 0.91-0.95), the PPV was 0.80 (95% CI 0.73-0.85), and the NPV was 1.0 (95% CI 0.99-1.0). For the diagnostic strategy using CT urography and flexible cystoscopy as a triage test for rigid cystoscopy and follow-up (option 2), patients with a positive CT urography score are referred directly for rigid cystoscopy, patients with an equivocal score are referred for flexible cystoscopy and patients with a normal score undergo clinical follow-up. Sensitivity was 0.95 (95% CI 0.90-0.97), specificity was 0.98 (95% CI 0.97-0.99), the PPV was 0.93 (95% CI 0.87-0.96), and the NPV was 0.99 (95% CI 0.97-0.99). For voided urine cytology, if scores of 0-3 were classified as negative and 4-5 as positive for bladder cancer, sensitivity was 0.38 (95% CI 0.31-0.45), specificity was 0.98 (95% CI 0.97-0.99), the PPV was 0.82 (95% CI 0.72-0.88) and the NPV was 0.84 (95% CI 0.81-0.87).

CONCLUSIONS

There is a clear advantage for the diagnostic strategy using CT urography and flexible cystoscopy as a triage test for rigid cystoscopy and follow-up (option 1), in which patients with a positive CT urography score for bladder cancer are directly referred for rigid cystoscopy, but all other patients undergo flexible cystoscopy. Diagnostic accuracy is the same as for the additional test strategy with the advantage of a 17% reduction of the number of flexible cystoscopies performed. The sensitivity of voided urine cytology is too low to justify its continuing use in a hospital haematuria rapid diagnosis clinic using CT urography and flexible cystoscopy.

Newer CT applications and their alternatives: what is appropriate in children?

Innovations in image acquisition and reconstruction technologies have greatly expanded the range of CT applications available in the routine clinical setting. CT images of sub-millimeter resolution can now be acquired of entire body regions in a few seconds or even sub-second time, allowing depiction of fine anatomical detail uncompromised by motion artifact. With sophisticated visualization software, image data can be processed into multiplanar, volume-rendered, cine and other formats to better display anatomical abnormalities and facilitate newer applications such as CT angiography, enterography, urography, tracheobronchography and cardiac CT. Newer applications including dual-energy material decomposition CT are furthering the transition of CT from a purely morphological to a combined anatomical, functional and metabolic imaging technique. These newer applications have largely been pioneered in adult populations, and heightened concern of the risk of carcinogenesis from ionizing radiation tempers dissemination of their use in children. Similar information can often be gleaned from alternative imaging modalities without ionizing radiation exposure, such as MRI and US, and what is most appropriate in children will depend on relative diagnostic efficacy, cost, availability and local expertise.